汽车悬架系统中英文对照外文翻译文献
中英文文献翻译—非独立悬架
附录A 外文文献The structural characteristics of non-independent suspension on both sides of the wheel is an integral frame connected by the wheels together with the adoption of flexible suspension bridge hanging in the frame or body of the following. Non-independent suspension has a simple structure, low cost, high strength, easy maintenance, driving changes in the small front wheel alignment advantages, but because of its comfort and handling stability are poor, largely in the modern car is no longer in use more used in trucks and large passenger on. Independent suspension on each side of the wheel is individually through the elastic suspension is hanging in the frame or body below. The advantages are: light weight, reduced body shocks, and improve adhesion of the wheels on the ground; available small soft spring stiffness, improve vehicle comfort; can reduce engine position, car center of gravity is reduced, thereby improve the car's driving stability; about beating the wheel alone, independent of each other, can reduce the body's tilt and vibration. However, there are complex independent suspension, high cost and maintenance problem of inaccessibility. Modern cars are mostly used independent suspension, according to the different structure, independent wishbone suspension can be divided into longitudinal arm, multi-link, candle and McPherson suspension and so on. Arm Suspension means the horizontal plane in the car wheel independent suspension swing, according to the number of how many arm is divided into wishbone and single-arm suspension. Single-Arm has a simple structure, roll center height, with a strong anti-roll capability advantages. But with the increased speed of modern vehicles, roll center is too high will cause the wheel tread beats changes, tire wear increased, and in a sharp turn around the wheel vertical force when the transfer is too large, resulting in increased rear extraversion. Reduce rear-wheel cornering stiffness, resulting in a serious condition high-speed drift. Single-wishbone independent suspension in the rear suspension on a multi-application, but can not meet the requirements of high speed, the current limited application. Multi-link suspension are combined by the root pole position change control of the wheel suspension. Multi-link can wheel around the axis line with the vehicle at an angle within the swing axis is horizontal arm and vertical arm of the compromise, choose the right arm with the motor axis into a vertical line of the angle, can be varying degrees of access to wishbone suspension with the advantages of vertical arm, which can meet different performance requirements. Multi-link suspension of the main advantages are: the wheel tread and beating little change before the beam, both cars are in driving, braking status can be carried out by the driver of the Yi Tu smooth transition to its shortcomings in the automotive when the phenomenon of high-speed shaft swing. Mainly in the FR-link drive mode, and around the back axle of the integration (and the middle of the differential rigid connection) for use where, in the past to use more leaf spring support body, and now from the increased driving comfort considerations, multi-use Link back to say that the swing arm type and style, and use a good coil spring ride. Link in the left side of a pair, divided into upper and lower tie rod, as thelateral force transmission (car drivers) body, usually with a horizontal thrust bar again with the composition of the five-link form. Connect one end of the body lateral thrust rod, one end of the connecting axle, its purpose is to prevent the axle (or body) horizontal traverse. When the axle moves up and down because of the rough, the lateral thrust rod will be connected to contacts with the body axis, an art movement arc, through the General Assembly if the swing angle made between the axles and the body produces significant lateral relative motion, and the lower arm principle similar to the horizontal thrust rod longer than should be designed to reduce the swing angle. Link suspension and axle forming an integrated whole, the mass of the spring below, and not the independence movement around the wheel, so to face bumpy road vehicle impact energy generated by relatively large, poor ride comfort. So there arm methods, this approach is the only fixed-axle differential among left and right half shaft in the differential and universal joints located between the wheel and the center of its swing, used between the wheel and the frame Y-connection under the arm. "Y" at one end and a separate rigid wheel, the other two endpoints and the frame to connect and form a rotation axis. According to the rotation axis is parallel with the axle, swing arm type suspension is divided into full drag-type arm and half drag-style swing arm, parallel to the whole drag-style, non-parallel type is called semi-drag.Because comfort is the car one of the most important performance, and comfort with the body's natural vibration characteristics, whereas the body's natural vibration characteristics of a feature associated with the suspension. Therefore, the vehicle suspension is to ensure the comfort of the important parts. Meanwhile, the vehicle suspension as a frame (or body) and the axle (or wheel) to make the connection between the mechanical power transmission, it is important to ensure the safety of motor cars and parts. Therefore, the vehicle suspension components are often incorporated into the car as an important technical specifications of the table, as one of the indicators to measure the quality of cars.Active suspension is developed in the last ten years, a new type of computer-controlled suspension. It brings together mechanics and electronics, technical knowledge, is a more complex high-tech devices. For example, the installation of the French Citroen Sang Diya active suspension, the center of the car suspension system is a microcomputer, the suspension on five kinds of sensors were transmitted to the micro-computer speed, front wheel brake pressure, ride a fixed throttle pedal speed, body vertical amplitude and frequency, steering wheel angle and steering velocity data. Computer continuously receives the data and with pre-set threshold to compare, select the appropriate suspension state. Meanwhile, the microcomputer independent control of each wheel on the implementation of the components only by controlling the hydraulic shock absorber of changes within the tic, which can at any time, any wheels that meet the requirements of the suspension movement. Therefore, Sang Diya car a wide range of driving mode selection, drivers need only flip a deputy on the dashboard in the "normal" or "sport" button will automatically set the car's suspension in top condition, in order to The best comfort.Active suspension control of body movement with the function. When the car when braking or turning the inertia caused by the spring deformation, the active suspension forces will have to confront a force used to reduce the body position changes. 2000 Mercedes-Benz CL models such as Germany-based sports car, when the suspension when the vehicle turning sensor will immediately detect the body's tilt and lateral acceleration. Computer based on the sensor information, and pre-set threshold value of calculations to determine what position once the load will be added to the suspension on how to minimize body tilt.Wishbone independent suspension by upper and lower arm is so long, is divided into equal length wishbone and unequal length wishbone suspension of two. And other long-wishbone suspension in the wheel up and down beats, kingpin inclination to maintain the same, but the wheelbase change greatly (and similar single-Arm), resulting in severe tire wear, is now rarely used. The unequal length wishbone suspension, when properly selected to optimize the length of the upper and lower arm, and through a reasonable layout, you can make changes in tread and the front wheel alignment parameters were within acceptable limits to ensure the car good driving stability. Present unequal length wishbone suspension has been widely used in cars, front and rear suspension, the part of the sports car and the car's rear wheel has adopted this - suspension structure. Suspension roleSuspension is an important vehicle in the assembly, it is to frame the flexibility to link with the wheel bearing on a variety of performance cars. In appearance, a car suspension only by a number of rods, cylinders and springs form, but do not think it is very simple, opposite a car suspension is more difficult to achieve the perfect vehicle assembly requirements, this is because both suspension to meet the car's comfort requirements, but also to meet the requirements of its handling and stability, while these two aspects are mutually antagonistic. For example, in order to achieve good comfort, requires much buffer vehicle vibration, the spring must be designed so soft, but, it is easy for the spring soft place car brake "nod", the "rise" and roll about serious adverse tendency is not conducive to the car turn easily lead to vehicle handling and instability. Therefore, if the suspension is poorly designed, will significantly affect the performance of automotive products (such as turning a heavy, swing, tire eccentric wear and affect tire life, etc.).附录B 中文翻译非独立悬架的结构特点是两侧车轮由一根整体式车架相连,车轮连同车桥一起通过弹性悬架悬挂在车架或车身的下面。
汽车车辆底盘外文文献翻译、中英文翻译、外文翻译
ChassisChassis include the clutch , the transmission, the drive shaft, the final drive assembly, the front suspension, the rear suspension, the steering system ,the brake system, the wheels and tires.1.clutchThe engine produces the power to drive the vehicle . The drive line or drive train transfer the power of the engine to the wheels . The drive train consists of the parts from the back of the flywheel to the wheels . These parts include the clutch , the transmission ,the drive shaft ,and the final drive assembly .The clutch which includes the flywheel ,clutch disc , pressure plate , springs , pressure plate cover and the linkage necessary to operate the clutch is a rotating mechanism between the engine and the transmission . It operates through friction which comes from contact between the parts . That is the reason why the clutch is called a friction mechanism . After engagement, the clutch must continue to transmit all engine torque to transmission depending on the friction without slippage . The clutch is also used to disengage the engine from the drive train whenever the gears in the transmission are being shifted from gear ratio to another .To start the engine or shift the gears , the driver has to depress the clutch pedal with the purpose of disengagement the transmission from the engine . At that time , the driven members connected to the transmission input shaft are either stationary or rotating at a speed that is slower of faster than the driving members connected to engine crankshaft . There is no spring pressure on the clutch assembly parts . So there is no friction between the driving members and driven members . As the driver lets loose the clutch pedal , spring pressure increase on the clutch parts . Friction between the parts also increases . The pressure exerted by the springs on the driven members is controlled by the driver through the clutch pedal and linkage . The positive engagement of the driving and driven members is made possible the friction between the surfaces of the members . When full spring pressure is applied , the speed of the driving and driven members should be the same . At the moment , the clutch must actas a coupling device and transmit all engine power to the transmission , without slipping .However , the transmission should be engaged to the engine gradually in order to operate the car smoothly and minimize torsional shock on the drive train because an engine at idle just develop little power . Otherwise , the driving members are connected with the driven members too quickly and the engine would be stalled .The flywheel is a major part of the clutch . The flywheel mounts to the engine‟s crankshaft and transmits engine torque to the clutch assembly . The flywheel , when coupled with the clutch disc and pressure plate makes and breaks the flow of power the engine to the transmission .The flywheel provides a mounting location for the clutch assembly as well . When the clutch is applied , the flywheel transfers engine torque to the clutch disc . Because of its weight , the flywheel helps to smooth engine operation . The flywheel also has a large ring gear at its outer edge , which engages with a pinion gear on the starter motor during engine cranking .The clutch disc fits between the flywheel and the pressure plate . The clutch disc has a splined hub that fits over splines on the transmission input shaft . A splined hub has grooves that match splines on the shaft . These splines fit in the grooves . Thus , the two parts held together . However , back –and –forth movement of the disc on the shaft is possible . Attached to the input shaft , the disc turns at the speed of the shaft .The clutch pressure plate is generally made of cast iron . It is round and about the same diameter as the clutch disc . One side of the pressure plate is machined smooth . This side will press the clutch disc facing are against the flywheel . The outer side has shapes to facilitate attachment of spring and release mechanism . The two primary types of pressure plate assemblies are coil spring assembly and diaphragm spring .In a coil spring clutch the pressure plate is backed by a number of coil springs and housed with them in a pressed –steed cover bolted to the flywheel . The spring push against the cover . Neither the driven plate nor the pressure plate is connected rigidly to the flywheel and both can move either towards it o away . When the clutch pedal is depressed a thrust pad riding on a carbon or ball thrust bearing is forced towards the flywheel . Levers pivoted sothat they engage with the thrust pad at one end and the pressure plate tat the other end pull the pressure plate back against its springs . This releases pressure on the driven plate disconnecting the gearbox from the engine .Diaphragm spring pressure plate assemblies are widely used in most modern cars . The diaphragm spring is a single thin sheet of metal which yields when pressure is applied to it . When pressure is removed the metal spring back to its original shape . The center portion of the diaphragm spring is slit into numerous fingers that act as release levers . When the clutch assembly rotates with the engine these weights are flung outwards by centrifugal plate and cause the levers to press against the pressure plate . During disengagement of the clutch the fingers are moved forward by the release bearing . The spring pivots over the fulcrum ring and its outer rim moves away from the flywheel . The retracting spring pulls the pressure plate away from the clutch plate thus disengaging the clutch .When engaged the release bearing and the fingers of the diaphragm spring move towards the transmission . As the diaphragm pivots over the pivot ring its outer rim forces the pressure plate against the clutch disc so that the clutch plate is engaged to flywheel .The advantages of a diaphragm type pressure plate assembly are its compactness , lower weight , fewer moving parts , less effort to engage , reduces rotational imbalance by providing a balanced force around the pressure plate and less chances of clutch slippage .The clutch pedal is connected to the disengagement mechanism either by a cable or , more commonly , by a hydraulic system . Either way , pushing the pedal down operates the disengagement mechanism which puts pressure on the fingers of the clutch diaphragm via a release bearing and causes the diaphragm to release the clutch plate . With a hydraulic mechanism , the clutch pedal arm operates a piston in the clutch master cylinder . This forces hydraulic fluid through a pipe to the cutch release cylinder where another operates the clutch disengagement mechanism by a cable .The other parts including the clutch fork , release bearing , bell – housing , bell housing cover , and pilot bushing are needed to couple and uncouple the transmission . The clutch fork , which connects to the linkage , actually operates the clutch . The release bearing fits between the clutch fork and the pressure plate assembly . The bell housing covers the clutchassembly . The bell housing cover fastens to the bottom of the bell housing . This removable cover allows a mechanic to inspect the clutch without removing the transmission and bell housing . A pilot bushing fits into the back of the crankshaft and holds the transmission input shaft .2.AUTOMATIC TRANSMISSIONThe modern automatic transmission is by far , the most complicated mechanical component in today‟s automobile . It is a type of transmission that sifts itself . A fluid coupling or torque converter is used instead of a manually operated clutch to connect the transmission to the engine .There are two basic types of automatic transmission based on whether the vehicle is rear wheel drive or front wheel drive . On a rear wheel drive car , the transmission is usually mounted to the back of the engine and is located under the hump in the center of the floorboard alongside the gas pedal position . A drive shaft connects the transmission to the final drive which is located in the rear axle and is used to send power to the rear wheels . Power flow on this system is simple and straight forward going from the engine , through the torque converter , then trough the transmission and drive shaft until it reaches the final drive where it is split and sent to the two rear transmission .On a front wheel drive car , the transmission is usually combined with the final drive to form what is called a transaxle . The engine on a front wheel drive car is usually mounted sideways in the car with the transaxle tucked under it on the side of the engine facing the rear of the car . Front axles are connected directly to the transaxle and provide power to front wheels . In this example , power floes from the engine , through the torque converter to a larger chain that sends the power through a 180 degree turn to the transmission that is along side the engine . From there , the power is routed through the transmission to the final drive where it is split and sent to the two front wheels through the drive axles .There are a number of other arrangements including front drive vehicles where the engine is mounted front to back instead of sideways and there are other systems that drive all four wheels but the two systems described here are by far the most popular . A much lesspopular rear and is connected by a drive shaft to the torque converter which is still mounted on the engine . This system is found on the new Corvette and is used in order to balance the weight evenly between the front and rear wheels for improved performance and handling . Another rear drive system mounts everything , the engine , transmission and final drive in the rear . This rear engine arrangement is popular on the Porsche.The modern automatic transmission consists of many components and systems that designed to work together in a symphony of planetary gear sets , the hydraulic system, seals and gaskets , the torque converter , the governor and the modulator or throttle cable and computer controls that has evolved over the years into what many mechanical inclined individuals consider to be an art from . Here try to used simple , generic explanation where possible to describe these systems .1)Planetary gear setsAutomatic transmission contain many gears in various combinations . In a manual transmission , gears slide along shafts as you move the shift lever from one position to another , engaging various sizes gears as required in order to provide the correct gear ratio . In an automatic transmission , how ever , the gears are never physically moved and are always engaged to the same gears . This is accomplished through the use of planetary gear sets .The basic planetary gear set consists of a sun gear , a ring and two or more planet gears , all remaining in constant mesh . The planet gears are connected to each other through a common carrier which allows the gears to spin on shafts called “pinions” which are attached to the carrier .One example of a way that this system can be used is by connecting the ring gear to the input shaft coming from the engine , connecting the planet carrier to the output shaft , and locking the sun gear so that it can‟t move . In this scenario , when we turn the ring gear , the planets will “walk” along the sun gear ( which is held stationary ) causing the planet carrier to turn the output shaft in the same direction as the input shaft but at a slower speed causing gear reduction ( similar to a car in first gear ) .If we unlock the sun gear and lock any two elements together , this will cause all three elements to turn at the same speed so that to output shaft will turn at the same rate of speed asthe input shaft . This is like a car that is third or high gear . Another way we can use a planetary gear set is by locking the planet carrier from moving , then applying power to the ring gear which will cause the sun gear to turn in opposite direction giving us reverse gear .The illustration in Figure shows how the simple system described above would look in an actual transmission . The input shaft is connected to the ring gear , the output shaft is connected to the planet carrier which is also connected to a “Multi-disk” clutch pack . The sun gear is connected to drum which is also connected to the other half of the clutch pack . Surrounding the outside of the drum is a band that can be tightened around the drum when required to prevent the drum with the attached sun gear from turning .The clutch pack is used , in this instance , to lock the planet carrier with the sun gear forcing both to turn at the same speed . If both the clutch pack and the band were released , the system would be in neutral . Turning the input shaft would turn the planet gears against the sun gear , but since noting is holding the sun gear , it will just spin free and have no effect on the output shaft . To place the unit in first gear , the band is applied to hold the sun gear from moving . To shift from first to high gear , the band is released and the clutch is applied causing the output shaft to turn at the same speed as the input shaft .Many more combinations are possible using two or more planetary sets connected in various way to provide the different forward speeds and reverse that are found in modern automatic transmission .2)Clutch packA clutch pack consists of alternating disks that fit inside a clutch drum . Half of the disks are steel and have splines that fit into groves on the inside of the drum . The other half have a friction material bonded to their surface and have splines on the inside edge that fit groves on the outer surface of the adjoining hub . There is a piston inside the drum that is activated by oil pressure at the appropriate time to squeeze the clutch pack together so that the two components become locked and turn as one .3)One-way ClutchA one-way clutch ( also known as a “sprag” clutch ) is a device that will allow a component such as ring gear to turn freely in one direction but not in the other . This effect is just like thatbicycle , where the pedals will turn the wheel when pedaling forward , but will spin free when pedaling backward .A common place where a one-way clutch is used is in first gear when the shifter is in the drive position . When you begin to accelerate from a stop , the transmission starts out in first gear . But have you ever noticed what happens if you release the gas while it is still in first gear ? The vehicle continues to coast as if you were in neutral . Now , shift into Low gear instead of Drive . When you let go of the gas in this case , you will feel the engine slow you down just like a standard shift car . The reason for this is that in Drive , one-way clutch is used whereas in Low , a clutch pack or a band is used .4)Torque ConverterOn automatic transmission , the torque converter takes the place of the clutch found on standard shift vehicles . It is there to allow the engine to continue running when the vehicle comes to a stop . The principle behind a torque converter is like taking a fan that is plugged into the wall and blowing air into another fan which is unplugged . If you grab the blade on the unplugged fan , you are able to hold it from turning but as soon as you let go , it will begin to speed up until it comes close to speed of the powered fan . The difference with a torque converter is that instead of using air it used oil or transmission fluid , to be more precise .A torque converter is a lager doughnut shaped device that is mounted between the engine and the transmission . It consists of three internal elements that work together to transmit power to the transmission . The three elements of the torque converter are the pump , the Turbine , and the Stator . The pump is mounted directly to the torque housing which in turn is bolted directly to the engine‟s crankshaft and turns at engine speed . The turbine is inside the housing and is connected directly to the input shaft of the transmission providing power to move the vehicle . The stator is mounted to a one-way clutch so that it can spin freely in one direction but not in the other . Each of the three elements has fins mounted in them to precisely direct the flow of oil through the converter .With the engine running , transmission fluid is pulled into the pump section and is pushed outward by centrifugal force until it reaches the turbine section which stars it running . The fluid continues in a circular motion back towards the center of the turbine where it entersthe stator . If the turbine is moving considerably slower than the pump , the fluid will make contact with the front of the stator fins which push the stator into the one way clutch and prevent it from turning . With the stator stopped , the fluid is directed by the stator fins to re-enter the pump at a “help” angle providing a torque increase . As the speed of the turbine catches up with the pump , the fluid starts hitting the stator blades on the back-side causing the stator to turn in the same direction as the pump and turbine . As the speed increase , all three elements begin to turn at approximately the same speed . Sine the …80s , in order to improve fuel economy , torque converters have been equipped with a lockup clutch which locks the turbine to the pump as the vehicle reaches approximately 40-50 mph . This lockup is controlled by computer and usually won‟t engage unless the transmission is in 3rd or 4th gear .5)Hydraulic SystemThe hydraulic system is a complex maze of passage and tubes that sends that sends transmission fluid and under pressure to all parts of the transmission and torque converter and . Transmission fluid serves a number of purpose including : shift control ,general lubrication and transmission cooling . Unlike the engine ,which uses oil primary for lubrication ,every aspect of a transmission …s function is dependant on a constant supply of fluid is send pressure . In order to keep the transmission at normal operating temperature , a portion of the fluid is send to through one of two steel tubes to a special chamber that is submerged in anti-freeze in the radiator . Fluid passing through this chamber is cooled and then returned to the transmission through the other steel tube . A typical transmission has an avenge of ten quarts of fluid between the transmission , torque converter , and cooler tank , In fact , most of the components of a transmission are constantly submerged in fluid including the clutch packs and bands . The friction surfaces on these parts are designed to operate properly only when they are submerged in oil .6)Oil PumpThe transmission oil pump ( not to confused with the pump element inside the torque converter ) is responsible for producing all the oil pressure that is required in the transmission . The oil pump is mounted to front of the transmission case and is directly connected to aflange on the engine crankshaft , the pump will produce pressure whenever the engine is running as there is a sufficient amount of transmission fluid available . The oil enters the pump through a filter that is located at bottom of the transmission oil pan and travels up a pickup tube directly to the oil pump . The oil is then sent , under pressure to the pressure regulator , the valve body and the rest of the components , as required .7)Valve BodyThe valve body is the control center of the automatic transmission . It contains a maze of channels and passages that direct hydraulic fluid to the numerous valves which when activate the appropriate clutch pack of band servo to smoothly shift to the appropriate gear for each driving situation . Each of the many valves in the valve body has a specific purpose and is named for that function . For example the 2-3 shift valve activates the 2nd gear up-shift or the 3-2 shift timing valve which determines when a downshift should occur .The most important valve and the one that you have direct control over is the manual valve. The manual valve is directly connected to the gear shift handle and covers and uncovers various passages depending on what position the gear shift is paced in . When you place the gear shift in Drive , for instance , the manual valve directs fluid to the clutch pack ( s ) that activates 1st gear . It also sets up to monitor vehicle speed and throttle position so that it can determine the optimal time and the force for the 1-2 shift . On computer controlled transmission , you will also have electrical solenoids that are mounted in the valve body to direct fluid to the appropriate clutch packs or bands under computer control to more precisely control shift points .8)Seals and GasketsAn automatic transmission has many seals and gaskets to control the flow of hydraulic fluid and to keep it from leaking out . There are two main external seals : the front seal and the rear seal . The front seal seals the point where the torque converter mounts to the transmission case . This seal allows fluid to freely move from the converter to the transmission but keeps the fluid from leaking out . The rear seal keeps fluid from leaking past the output shaft .A seal is usually made of rubber ( similar to the rubber in a windshield wiper blade )and is used to keep oil from leaking past a moving part such as a spinning shaft . In some cases , the rubber is assisted by a spring that holds he rubber in close contact with the spinning shaft .A gasket is a type of seal used to seal two stationary parts that are fasted together . Some common gasket materials are : paper , cork , rubber , silicone and soft metal .Aside from the main seals , there are also a number of other seals and gasket that vary from transmission to transmission . A common example is the rubber O-ring that seals the shaft for the shift control lever . This is the shaft that you move when you manipulate the gear shifter . Another example that is common to most transmission is the oil pan gasket . In fact , seals are required anywhere that a device needs to pass through the transmission case with each one being a potential source for leaks .9)Computer ControlsThe computer uses sensors on the engine and transmission to detect such things as throttle position , vehicle speed , engine speed , engine load , stop light switch position , etc . to control exact shift points as well as how soft or firm the shift should be . Some computerized transmission even learn your driving style and constantly adapt to it so that every shift is timed precisely when you would need it .Because of computer controls , sports models are coming out with the ability to take manual control of the transmission as through it were a stick shift lever through a special gate , then tapping it in one direction or the other in order to up-shift at will . The computer monitors this activity to make sure that the driver dose not select a gear that could over speed the engine and damage it .Another advantage to these “ smart” transmission is that they have a self diagnostic mode which can detect a problem early on and warn you with an indicator light on the dash .A technician can then plug test equipment in and retrieve a list of trouble codes that will help pinpoint where the problem is .3.The Differential SystemWhen a vehicle is cornered the inner wheel moves through a shorter distance than theouter wheel . This means that the inner wheel must slow down and the outer wheel must speed up . During this period it is desirable that each driving maintains its driving action . The differential performs these two tasks . The principle of the bevel type differential can be seen if the unit is considered as two discs and a lever .When the vehicle is traveling straight , the lever will divide the diving force equally and both discs will move the same amount .When the vehicle corners , the driving will still be divided equally but the inner disc will now move through a smaller distance ;this will cause the lever to pivot about its center which will prize forward the outer disc to give it a greater movement . This action shows that the torque applied to each driving wheel is always equal – hence the differential is sometimes called a torque equalizer .4.Brake SystemThe breaking system is the most important system in cars . If the brakes fail , the result can be disastrous . Brakes are actually energy conversion devices , which convert the kinetic energy ( momentum ) of the vehicle into thermal ( heat ) . When stepping on the brakes , the driver commands a stopping force ten times as powerful as the force that puts the car in motion . The braking system can exert thousands of pounds of pressure on each of the four brakes .The brake system is composed of the following basic components : the “master cylinder” which is located under the hood , and is directly connected to the brake pedal , converts driver foot‟s mechanical pressure into hydraulic pressure . Steel “brake lines” and flexible “brake hoses” connect the master cylinder to the “slave cylinders” located at each wheel . Brake fluid , specially designed to work in extre me condition , fills the system . “Shoes” and “Pads” are pushed by the salve cylinders to contact the “drum” and “rotors” thus causing drag , which ( hopefully ) slows the car .The typical brake system consists of disk brakes in front and either disk or drum brakes in the rear connected by a system of tubes and hoses that link the brake at each wheel to the master cylinder .Stepping on the brake pedal , a plunger is actually been pushing against in the master cylinder which forces hydraulic oil ( brake fluid ) through a series of tubes and hoses to the braking unit at each wheel . Since hydraulic fluid ( or any fluid for that matter ) cannot be compressed , pushing fluid through a pipe is just like pushing a steel bar through pipe . Unlike a steel bar , however , fluid can be directed through many twists and turns on its way to its destination , arriving with the exact same motion and pressure that it started with . It is very important that the fluid is pure liquid and that there are no air bubbles in it . Air can compress , which causes a sponginess to the pedal and severely reduced braking efficiency . If air is suspected , then the system must be bled to remove the air . There are “bleeder screws” at each wheel and caliper for this purpose .On a disk brakes , the fluid from the master cylinder is forced into a caliper where it pressure against a piston . The piton , in-turn , squeezes two brake pads against the disk ( rotor ) which is attached to the wheel , forcing it to slow down or stop . This process is similar to the wheel ,causing the wheel to stop . In either case , the friction surface of the pads on a disk brake system , on the shoes on a drum brake convert the forward motion of the vehicle into heat . Heat is what causes the friction surfaces ( lining ) of the pads and shoes to eventually wear out and require replacement .Brake fluid is a special oil that has specifics properties . It is designed to withstand cold temperatures without thickening as well as very high temperatures without boiling . ( If the brake fluid should boil , it will cause you to have a spongy pedal and the car will be hard to stop ) .The brake fluid reservoir is on top of the master cylinder . Most cars today have a transparent reservoir so that you can see the level without opening the cover . The brake fluid lever will drop slightly as the brake pads wear . This is a normal condition and no cause for concern . If the lever drops noticeably over a short period of time or goes down to about two thirds full , have your brakes checked as soon as possible . Keep the reservoir covered expect for the amount of time you need to fill it and never leave a can of brake fluid uncovered . Brake fluid must maintain a very high boiling point . Exposure to air will cause the fluid to absorb moisture which will lower that boiling point .。
汽车悬架原理外文文献翻译中英文
汽车悬架原理外文文献翻译(含:英文原文及中文译文)文献出处:Journal of Biomechanics, 2013, 4(5):30-39.英文原文The rinciple of Car SuspensionsWilliam HarrisUniversity of MichiganWhen people think of automobile performance, they normally think of horsepower, torque and zero-to-60 acceleration. But all of the power generated by a piston engine is useless if the driver can't control the car. That's why automobile engineers turned their attention to the suspension system almost as soon as they had mastered the four-stroke internal combustion engine.The job of a car suspension is to maximize the friction between the tires and the road surface, to provide steering stability with good handling and to ensure the comfort of the passengers. In this article, we'll explore how car suspensions work, how they've evolved over the years and where the design of suspensions is headed in the future.1.V ehicle DynamicsIf a road were perfectly flat, with no irregularities, suspensions wouldn't be necessary. But roads are far from flat. Even freshly paved highways have subtle imperfections that can interact with the wheels of acar. It's these imperfections that apply forces to the wheels. According to Newton's laws of motion, all forces have both magnitude and direction. A bump in the road causes the wheel to move up and down perpendicular to the road surface. The magnitude, of course, depends on whether the wheel is striking a giant bump or a tiny speck. Either way, the car wheel experiences a vertical acceleration as it passes over an imperfection. Without an intervening structure, all of wheel's vertical energy is transferred to the frame, which moves in the same direction. In such a situation, the wheels can lose contact with the road completely. Then, under the downward force of gravity, the wheels can slam back into the road surface. What you need is a system that will absorb the energy of the vertically accelerated wheel, allowing the frame and body to ride undisturbed while the wheels follow bumps in the road.The study of the forces at work on a moving car is called vehicle dynamics, and you need to understand some of these concepts in order to appreciate why a suspension is necessary in the first place. Most automobile engineers consider the dynamics of a moving car from two perspectives:1)Ride - a car's ability to smooth out a bumpy road2)Handling - a car's ability to safely accelerate, brake and cornerThese two characteristics can be further described in three important principles - road isolation, road holding and cornering. The table belowdescribes these principles and how engineers attempt to solve the challenges unique to each.A car's suspension, with its various components, provides all of the solutions described.2.The Chassis SystemThe suspension of a car is actually part of the chassis, which comprises all of the important systems located beneath the car's body.These systems include:1) T he frame - structural, load-carrying component that supports the car's engine and body, which are in turn supported by the suspension2) T he suspension system - setup that supports weight, absorbs and dampens shock and helps maintain tire contact3) T he steering system - mechanism that enables the driver to guide and direct the vehicle4) T he tires and wheels - components that make vehicle motion possible by way of grip and/or friction with the roadSo the suspension is just one of the major systems in any vehicle.With this big-picture overview in mind, it's time to look at the three fundamental components of any suspension: springs, dampers and anti-sway bars.3.SpringsToday's springing systems are based on one of four basic designs:1) Coil springs - This is the most common type of spring and is, in essence, a heavy-duty torsion bar coiled around an axis. Coil springs compress and expand to absorb the motion of the wheels.2) Leaf springs - This type of spring consists of several layers of metal (called "leaves") bound together to act as a single unit. Leaf springs were first used on horse-drawn carriages and were found on most American automobiles until 1985. They are still used today on most trucks and heavy-duty vehicles.3) Torsion bars - Torsion bars use the twisting properties of a steel bar to provide coil-spring-like performance. This is how they work: One end of a bar is anchored to the vehicle frame. The other end is attached to a wishbone, which acts like a lever that moves perpendicular to the torsion bar. When the wheel hits a bump, vertical motion is transferred to the wishbone and then, through the levering action, to the torsion bar. Thetorsion bar then twists along its axis to provide the spring force. European carmakers used this system extensively, as did Packard and Chrysler in the United States, through the 1950s and 1960s. 4) Air springs - Air springs, which consist of a cylindrical chamber of air positioned between the wheel and the car's body, use the compressive qualities of air to absorb wheel vibrations. The concept is actually more than a century old and could be found on horse-drawn buggies. Air springs from this era were made from air-filled, leather diaphragms, much like a bellows; they were replaced with molded-rubber air springs in the 1930s.Based on where springs are located on a car -- i.e., between the wheels and the frame -- engineers often find it convenient to talk about the sprung mass and the unsprung mass.4.Sprung and Unsprung MassThe sprung mass is the mass of the vehicle supported on the springs, while the unsprung mass is loosely defined as the mass between the road and the suspension springs. The stiffness of the springs affects how the sprung mass responds while the car is being driven. Loosely sprung cars, such as luxury cars (think Lincoln Town Car), can swallow bumps and provide a super-smooth ride; however, such a car is prone to dive and squat during braking and acceleration and tends to experience body sway or roll during cornering. Tightly sprung cars, such as sports cars (think Mazda Miata), are less forgiving on bumpy roads, but they minimizebody motion well, which means they can be driven aggressively, even around corners.So, while springs by themselves seem like simple devices, designing and implementing them on a car to balance passenger comfort with handling is a complex task. And to make matters more complex, springs alone can't provide a perfectly smooth ride. Why? Because springs are great at absorbing energy, but not so good at dissipating it. Other structures, known as dampers, are required to do this.5.Shock AbsorbersUnless a dampening structure is present, a car spring will extend and release the energy it absorbs from a bump at an uncontrolled rate. The spring will continue to bounce at its natural frequency until all of theenergy originally put into it is used up. A suspensionbuilt on springs alone would make for an extremely bouncy ride and, depending on the terrain, an uncontrollable car.Enter the shock absorber, or snubber, a device that controls unwanted spring motion through a process known as dampening. Shock absorbers slow down and reduce the magnitude of vibratory motions by turning the kinetic energy of suspension movement into heat energy that can be dissipated through hydraulic fluid. To understand how this works, it's best to look inside a shock absorber to see its structure and function.A shock absorber is basically an oil pump placed between the frame of the car and the wheels. The upper mount of the shock connects to the frame (i.e., the sprung weight), while the lower mount connects to the axle, near the wheel (i.e., the unsprung weight). In a twin-tube design, one of the most common types of shock absorbers, the upper mount is connected to a piston rod, which in turn is connected to a piston, which in turn sits in a tube filled with hydraulic fluid. The inner tube is known as the pressure tube, and the outer tube is known as the reserve tube. The reserve tube stores excess hydraulic fluid.When the car wheel encounters a bump in the road and causes the spring to coil and uncoil, the energy of the spring is transferred to the shock absorber through the upper mount, down through the piston rod and into the piston. Orifices perforate the piston and allow fluid to leakthrough as the piston moves up and down in the pressure tube. Because the orifices are relatively tiny, only a small amount of fluid, under great pressure, passes through. This slows down the piston, which in turn slows down the spring.Shock absorbers work in two cycles -- the compression cycle and the extension cycle. The compression cycle occurs as the piston moves downward, compressing the hydraulic fluid in the chamber below the piston. The extension cycle occurs as the piston moves toward the top of the pressure tube, compressing the fluid in the chamber above the piston.A typical car or light truck will have more resistance during its extension cycle than its compression cycle. With that in mind, the compression cycle controls the motion of the vehicle's unsprung weight, while extension controls the heavier, sprung weight.All modern shock absorbers are velocity-sensitive -- the faster the suspension moves, the more resistance the shock absorber provides. This enables shocks to adjust to road conditions and to control all of the unwanted motions that can occur in a moving vehicle, including bounce, sway, brake dive and acceleration squat.6.Struts and Anti-sway BarsAnother common dampening structure is the strut -- basically a shock absorber mounted inside a coil spring. Struts perform two jobs: They provide a dampening function like shock absorbers, and they provide structural support for the vehicle suspension. That means struts deliver a bit more than shock absorbers, which don't support vehicle weight -- they only control the speed at which weight is transferred in a car, not the weight itself.Because shocks and struts have so much to do with the handling of a car, they can be considered critical safety features. Worn shocks and struts can allow excessive vehicle-weight transfer from side to side and front to back. This reduces the tire's ability to grip the road, as well as handling and braking performance.7.Anti-sway BarsAnti-sway bars (also known as anti-roll bars) are used along with shock absorbers or struts to give a moving automobile additional stability. An anti-sway bar is a metal rod that spans the entire axle and effectively joins each side of the suspension together.When the suspension at one wheel moves up and down, the anti-sway bar transfers movement to the other wheel. This creates a more level ride and reduces vehicle sway. In particular, it combats the roll of a car on its suspension as it corners. For this reason, almost all cars today are fitted with anti-sway bars as standard equipment, although if they're not, kits make it easy to install the bars at any time.8.The Future of Car SuspensionsWhile there have been enhancements and improvements to both springs and shock absorbers, the basic design of car suspensions has not undergone a significant evolution over the years. But all of that's about to change with the introduction of a brand-new suspension design conceived by Bose -- the same Bose known for its innovations in acoustic technologies. Some experts are going so far as to say that the Bose suspension is the biggest advance in automobile suspensions since the introduction of an all-independent design.How does it work? The Bose system uses a linear electromagnetic motor (LEM) at each wheel in lieu of a conventional shock-and-spring setup. Amplifiers provide electricity to the motors in such a way that theirpower is regenerated with each compression of the system. The main benefit of the motors is that they are not limited by the inertia inherent in conventional fluid-based dampers. As a result, an LEM can extend and compress at a much greater speed, virtually eliminating all vibrations in the passenger cabin. The wheel's motion can be so finely controlled that the body of the car remains level regardless of what's happening at the wheel. The LEM can also counteract the body motion of the car while accelerating, braking and cornering, giving the driver a greater sense of control.Unfortunately, this paradigm-shifting suspension won't be available until 2009, when it will be offered on one or more high-end luxury cars. Until then, drivers will have to rely on the tried-and-true suspension methods that have smoothed out bumpy rides for centuries.中文译文汽车悬架原理研究作者:威廉·哈里斯密歇根大学当人们想到汽车性能时,他们通常会联想到马力,扭矩和零到60码加速度。
外文翻译---悬架系统的基本元件
附录Ⅰ外文资料及翻译As we review suspension system components and how they work together, remember that a vehicle in motion is more than wheels turning. As the tire revolves, the suspension system is in a dynamic state of balance, continuously compensating and adjusting for changing driving conditions. Today's suspension system is automotive engineering at its best.The components of the suspension system perform six basic functions:1.Maintain correct vehicle ride height2.Reduce the effect of shock forces3.Maintain correct wheel alignment4.Support vehicle weight5.Keep the tires in contact with the road6.Control the vehicle’s direction of travelHowever, in order for this to happen, all the suspension components, both front and rear, must be in good working condition.MAIN COMPONENTS OF A MODERN SUSPENSION SYSTEMAt this point, it's important to understand that the main components of a moving vehicle suspension system are the Struts, Shock Absorbers, Springs and Tires. We will first turn our attention to the design and function of springs. In the following section we will thoroughly examine the function and design of shock absorbers and strut assemblies.The springs support the weight of the vehicle, maintain ride height, and absorb road shock..Springs are the flexible links that allow the frame and the body to ride relatively undisturbed while the tires and suspension follow the bumps in the road.Springs are the compressible link between the frame and the body. When an additional load is placed on the springs or the vehicle meets a bump in the road, the springs will absorb the load by compressing. The springs are a very important component of the suspension system that provides ride comfort. Shocks and strutshelp control how fast the springs and suspension are allowed to move, which is important in keeping tires in firm contact with the road.During the study of springs, the term bounce refers to the vertical (up and down) movement of the suspension system. The upward suspension travel that compresses the spring and shock absorber is called the jounce, or compression. The downward travel of the tire and wheel that extends the spring and shock absorber is called rebound, or extension.When the spring is deflected, it stores energy. Without shocks and struts the spring will extend and release this energy at an uncontrolled rate. The spring's inertia causes it to bounce and overextend itself. Then it re-compresses, but will again travel too far. The spring continues to bounce at its natural frequency until all of the energy originally put into the spring is used.If the struts or shock absorbers are worn and the vehicle meets a bump in the road, the vehicle will bounce at the frequency of the suspension until the energy of the bump is used up. This may allow the tires to lose contact with the road.Struts and shock absorbers that are in good condition will allow the suspension to oscillate through one or two diminishing cycles, limiting or damping excessive movement, and maintaining vertical loads placed upon the tires. This helps keep the tires in contact with the road.By controlling spring and suspension movement, components such as tie rods will operate within their design range and, while the vehicle is in motion, dynamic wheel alignment will be maintained.SPRING DESIGNSBefore discussing spring design, it is important to understand sprung and unsprung weight. Sprung weight is the weight supported by the springs. For example, the vehicle's body, transmission, frame, and motor would be sprung weight. Unsprung weight is the weight that is not carried by springs, such as the tires, wheels, and brake assemblies.The springs allow the frame and vehicle to ride undisturbed while the suspension and tires follow the road surface. Reducing unsprung weight will provide less road shock. A high sprung weight along with a low unsprung weight provides improved ride and also improved tire traction.There are four major spring designs in use today: coil, leaf, torsion bar, and air.Coil SpringsThe most commonly used spring is the coil spring. The coil spring is a length of round spring steel rod that is wound into a coil. Unlike leaf springs, conventional coil springs do not develop inter-leaf friction. Therefore, they provide a smoother ride.The diameter and length of the wire determine the strength of a spring. Increasing the wire diameter will produce a stronger spring, while increasing its length will make it more flexible.Spring rate, sometimes referred to as deflection rate, is used to measure spring strength. It is the amount of weight that is required to compress the spring 1 inch. For example: If it takes 100 lbs. to compress a spring 1inch, it would take to 200 lbs. to compress the spring 2 inches.Some coil springs are made with a variable rate. This variable rate is accomplished by either constructing this spring from materials having different thickness or by winding the spring so the coil will progressively compress at a higher rate. Variable rate springs provide a lower spring rate under unloaded conditions offering a smoother ride, and a higher spring rate under loaded conditions, resulting in more support and control.Coil springs require no adjustment and for the most part are trouble-free. The most common failure is spring sag. Springs that have sagged below vehicle design height will change the alignment geometry. This can create tire wear, handling problems, and wear other suspension components. During suspension service it is very important that vehicle ride height be measured. Ride height measurements not within manufacturer’s specifications require replacement of springs.Leaf SpringsLeaf springs are designed two ways: multi-leaf and mono-leaf. The multi-leaf spring is made of several steel plates of different lengths stacked together. During normal operation, the spring compresses to absorb road shock. The leaf springs bend and slide on each other allowing suspension movement.An example of a mono-leaf spring is the tapered leaf spring. The leaf is thick in the middle and tapers toward the two ends. Many of these leaf springs are made of a composite material, while others are made of steel.In most cases leaf springs are used in pairs mounted longitudinally (front to back). However, there are an increasing number of vehicle manufacturers using a single transverse (side to side) mounted leaf spring.Torsion BarAnother type of spring is the torsion bar. The torsion bar is a straight or L shaped bar of spring steel. Most torsion bars are longitudinal, mounted solidly to the frame at one end and connected to a moving part of the suspension at the other. Torsion bars may also be transverse mounted. During suspension movement, the torsion bar will twist, providing spring action.Air SpringsThe air spring is another type of spring that is becoming more popular on passenger cars, light trucks, and heavy trucks. The air spring is a rubber cylinder filled with compressed air. A piston attached to the lower control arm moves up and down with the lower control arm. This causes the compressed air to provide spring action. If the vehicle load changes, a valve at the top of the airbag opens to add or release air from the air spring. An onboard compressor supplies air.Tires as SpringsAn often-overlooked spring is the tire. Tires are air springs that support the total weight of the vehicle. The air spring action of the tire is very important to the ride quality and safe handling of the vehicle. As a matter of fact, tires may be viewed as the number-one ride control component. Tire size, construction, compound and inflation are very important to the ride quality of the vehicle.STRUT MOUNTDESIGNStrut mounts are vehicle specific, and there are numerous designs in use today on both front and rear suspension systems. The three most common designs are inner plate, center sleeve, and spacer bushing.The Inner Plate Design used by General Motors and some Ford applications feature an inner plate encased in molded rubber surrounded by upper and lower surface plates. The inner plate is designed so the strut piston rod cannot push through the upper or lower surface plate if the rubber core fails. This design generally does not require washers. Due to the fact that the upper and lower service plates mostly cover the rubber portion of the mount, it is difficult to see if the inner rubber bushing has failed. However, these components wear over time and with a thorough inspection a proper recommendation can be made. The bearing is located on the bottom of the strut mount and is not serviceable. Defective bearing will require replacement of the entire strut mount.The Center Sleeve Design used by Chrysler features a center sleeve that is molded to the rubber bushing. This design provides increased side to side stability.The strut stem extends through the center sleeve. Upper and lower retainer washers prevent the strut rod from pushing through the strut mount. The bearing is a separate component from the strut mount. If inspection reveals cracks or tears in the rubber bushing, replacement is required. If the bearing is found to be defective it can be replaced separately.The Spacer Bushing Design used by V olkswagen, Toyota, Mazda, Mitsubishi, and early Chrysler vehicles feature center positioning of the bearing and a separate inner bushing instead of a molded inner sleeve. The operation is similar to the style we just discussed except the bearing is pressed in the strut mount. The bearings, washer, and the upper plate retain the strut rod. If the rubber bushing is cracked, torn, or the bearing is binding or seized, the strut mount requires replacement.ANTI-SWAY BARSAnother important component of a suspension system is the anti-sway bar. This device is used along with shock absorbers to provide additional stability. The anti-sway bar is simply a metal rod connected to both of the lower control arms. When the suspension at one wheel moves up and down the anti-sway bar transfers the movement to the other wheel. In this way the sway bar creates a more level ride and reduces vehicle sway or lean during cornering.Depending of the anti-sway bar thickness and design, it can provide as much as 15% reduction in the amount of vehicle roll or sway during cornering.BUSHINGSBushings are used in many locations on the vehicle suspension system. Most bushings are made with natural rubber. However, in some cases, urethane compounds may be used. Bushings made of natural rubber offer high tensile (tear) strength and excellent stability at low temperatures. Natural rubber is an elastomeric material. Elastomeric refers to the natural elastic nature of rubber to allow movement of the bushing in a twisting plane. Movement is controlled by the design of the rubber element. Natural rubber requires no lubrication, isolates minor vibration, reduces transmitted road shock, operates noise free, and offers a large degree of bushing compliance. Bushing compliance permits movement without binding. Natural rubber resists permanent deflections, is water resistant and very durable. In addition, natural rubber offers high load carrying capabilities.As with all suspension system components, control arm bushings are dynamic components, meaning that they operate while the vehicle is in motion. Control armsact as locators because they hold the position of the suspension in relation to the chassis. They are attached to the vehicle frame with rubber elastomeric bushings. During suspension travel, the control arm bushings provide a pivot point for the control arm. They also maintain the lateral and vertical location of the control arm pivot points, maintain dynamic wheel alignment, reduce transmitted noise, road shock, and vibration, while providing resistance to suspension movement.During suspension travel the rubber portion of the bushing must twist to allow control arm movement. Control arm bushings that are in good condition act as a spring; that is, the rubber will spring back to the position from which it started. This twisting action of the rubber will provide resistance to suspension movement.As previously stated, control arm bushings are dynamic suspension components. As the control arm travels through jounce and rebound, the rubber portion of the bushing will twist and stretch. This action transfers energy into the bushing and generates heat.Excessive heat tends to harden the rubber. As the rubber bushing hardens, it tends to crack, break, and then disintegrate. Its temperature determines the life of a rubber bushing. Rough road conditions and/or defective shock absorbers or struts will allow excessive suspension movement creating more heat, which shortens the life of the bushings.Rubber bushings must not be lubricated with petroleum-based oil. A petroleum-based product will destroy the bushings. Instead, use a special tire rubber lubricant or a silicone based lubricant.Worn suspension bushings allow the control arm to change positions. This results in driveline vibration (primarily rear wheel drive rear control arm bushings), dynamic alignment angle changes, tire wear, and handling problems. Control arm bushing wear (looseness) will create a clunking sound while driving over rough roads.悬架系统的基本元件当我们复习悬架系统组成时,我记得它们是怎么工作的,一辆行驶车的汽车,更应该说是车轮的转动。
悬架系统的基本原理外文文献翻译、中英文翻译、外文翻译
悬架系统的基本原理外文文献翻译、中英文翻译、外文翻译悬架系统的基本原理悬架系统虽然不是汽车运行不可或缺的部件,但有了它人们可以获得更佳的驾驶感受。
简单来说,它是车身与路面之间的桥梁。
悬架的行程涉及到悬浮于车轮之上的车架,传动系的相对位置。
就像横跨于旧金山海湾之上的金门大桥,它连接了海湾两岸。
去掉汽车上的悬架就像是你做一次冷水潜泳通过海湾一样,你可以平安的渡过整个秋天,但会疼痛会持续几周。
想想滑板吧!它直接接触路面,你可以感受到每一块砖,裂隙及其撞击。
这简直就是一种令人全身都为之震颤的体验。
当轮子滑过路面时,就会在此产生震动、冲击,这种震动的旅程是对你的身体和勇气的检验。
如果你没感到随时都有被掀之势,那么你或许会乐在其中吧!这就是你会在没有悬架的汽车上将会体验到的。
汽车的悬架分为两种基本类型:整体和独立悬架。
整体悬架(也叫刚性梁、刚性轴)是联接车辆上下两部分的一种主要形式。
一如其名,它是用一根金属材料(一般是轴)来连接两侧车轮的。
钢板弹簧在车架之间起到缓冲作用;在两半轴中间装有差速器,允许两侧的轮子以不同的角速度旋转。
整体式悬架的车辆在行进中,由于两侧的车轮共用一根轴,因此当某一侧车轮跳动时,另一侧也会随之运动。
它们的反馈结果就像是一个整体。
可以想象到,这不可能有舒适的驾驶体验。
虽然可以借助于弹簧来衰减猛烈的震动,但仍然存在较强的震动。
那么既然如此,为什么还要使用这种悬架呢?第一,它很坚固,由于采用了一体化的结构,定轴式悬架系统具有着其他方式悬架不可替代的承载能力。
它们经常应用于行驶于较差路况的车辆。
你可以在卡车和重载车辆上见到它。
一种由固定轴式悬架变形系统叫做TIB悬架系统(或叫半固定轴式)。
在这种结构中,有两根刚性轴而非一根。
这种设计可兼得较大的刚性和较好的韧性,通常用于轻卡的前悬。
另一种常见的悬架系统是独立悬架,它由两个独立的“桥”连接车轮。
这种结构可以提供最舒适的乘坐环境,因此多用于乘用车、小型货车和其他小型车辆。
方程式赛车多连杆式后悬架结构模态分析外文文献翻译、中英文翻译、外文翻译
外文文献附录AAn Analysis of Idling Vibration for a Frame StructuredVehicleABSTRACTBy mandate of the Engineering Meetings Board, this paper has been approved for SAE publication upon completion of a peer review process by a minimum of three (3) industry experts under the supervision of the session organizer.All rights reserved. No part of this publication may be reproduced, stored in a retrieval system, or transmitted, in any form or by any means, electronic, mechanical, photocopying, recording, or otherwise, without the prior written permission of SAE.For permission and licensing requests contact:INTRODUCTIONOne of the defects of a diesel vehicle, which has fuel and economical efficiency, is idling vibration for a vehicle body. In a diesel engine, sharp pressure rise caused by the generation of the thermal energy affects the pistons. In the crank system, which converts the linear motion into the rotary motion, two types of reaction forces excite the engine block: the reaction caused by the alternation of the velocity vector in each moving parts, and by the non-uniform rotary motion generated by the finite number of cylinders. The forces transmit to an engine block, an engine foot, a rubber engine mount, a frame, a rubber cab-mount, and then a vehicle body, which make occupants uncomfortable.The idling vibration for large-sized commercial vehicles was estimated at the early development stage, and the measures against the vibration were taken by simulating the engine exciting forces with Souma…s met hod,and entering them to a vehicle model.In this paper, the idling vibration was determined by entering the engine exciting forces to the vehicle model, which was made of the finite element of the frame and the body for a small-sized recreational vehicle (RV). Also in this paper, how the natural modes for the frame changes in the vehicle condition is analyzed, and it was indicated that the natural frequency of the first-order vertical bending for the frame had a significant effect. ANALYSIS OF THE VEHICLE BODY VIBRATIONThe detail design process of a double wish-bone suspension is described. This suspension is designed for passenger‟s comfort and ride within the acceptable strength. Criterions are discussed for such purpose. Numerical methods are used in selecting the basic geometry parameters for steering and suspension parts. The process of design and check the section of two arms is described, which is design the suspension according to maxim perpendicular force and lateral force and check it according to the maxim perpendicular force and vertical force. And other consideration and components of the suspension is mentioned. At last, two kinds of drawings, part drawing and assembly drawing, for the suspension system is described.The role of a vehicle suspension is to provide good ride and handling performance; to ensure that steering control is maintained during maneuvering; to ensure that the vehicle responds favorable to control forces; and to provide isolation from high frequency vibration arising from tyre excitation [1,2].Comfort has becoming an increasingly important feature for nowadays vehicles. So the strategy for this suspension is also comfort. Double wish-bone suspension is now widely used in the high-class vehicles, such as BMW X5, Benz M-Class, Audi Q7, etc. But comfort is not exclusive to expensive vehicles. With the steady decreasing of car price, double wish-bone suspension will be seen on more and more family cars in the future. Since the double wish-bone suspension is influenced by several different parts, the success is gained by the careful balance of these parameters.No matter what type of the vehicle, the main parts of a double wish-bone suspension system are alike, which consists of an upper arm AB, a lower arm CD, a swivel pin BC, a spring, a damper and a wheel. Since the steering system influences the suspension system, it is also considered. The steering system has been abstracted to a rack EE‟, tie rod EF, and steering arm FG [2,3]. All these are shown in Figure 1.IDENTIFICATION OF THE ENGINE EXCITING FORCEThere are three paths for the engine to excite vibration to a vehicle body: through an engine mount, a driving system, and a tail pipe. In this paper, the path through an engine mount, which has a greatest effect, is studied. The various types of methods to identify the exciting force through an engine mount are known. In this paper, Souma‟s method is used. OUTLINE OF SOUMA’S METHODThe cause of the exciting force to an engine block in the controversial frequencydomain of the idling vibration is considered. First, the combustion pressure that acts on the pistons is considered to cause the vibration. However, assuming that a piston crankshaft does not move with a flywheel and an engine block fixed in some way, the engine components are supposed to be completely rigid in this frequency domain. In this situation, the engine block will not vibrate if the piston crankshaft does not move in spite of the rapid pressure rise in a combustion chamber due to the diesel combustion.Accordingly, the direct cause of the engine block vibration is not the combustion pressure but the reaction against the piston crankshaft movement. To determine the exciting force to the engine block, the reaction forces against the movement of the mass (mainly in crank system and piston system), which works inside and outside of the engine block, may be calculated.In Souma‟s method, the non-uniform rotary motion in the crank system is found by measuring the pulse generated in a ring gear of the flywheel. Then, the vertical motion in the connected piston system is calculated to determine the exciting force to the engine block using each mass specification value.VERIFICATION OF THE ACCURACY IN THE EXCITING FORCEThe exciting forces are added at the point corresponding to the crankshaft on the entire vehicle model (described later). The vibration on the head cover and the right engine foot, which the exciting forces mostly affect, is estimated. The results of comparing the calculation with the experiment are shown in Figure 2 and 3. In Figure 2 and 3, 5 types of calculated results are shown considering the idling rotation speed changes.In Figure 2 and 3, the calculation and the experiment are identified around 24 Hz, 48 Hz, and 72 Hz of 2nd, 4th, and 6th-orders at the speed of 720 rpm. The data of the left engine foot, which is not shown in this paper, is also almost identified. In this frequency domain, as for the vibration, the engine and the vehicle body are insulated by the engine mount. The body hardly affects the engine vibration. As the data of the experiment and the calculation is identified in this domain, the power plant modeling and the exciting force can be considered reasonable.However, around 12 Hz of 1st-orders, data is not much identified. In this frequency domain, the vibration of the engine and the vehicle body are mutually coupled through the engine mount. Therefore, the accuracy of the vehicle body model has a damaging effect. IMPROVEMENT OF THE MEASURING ACCURACY IN LOW-FREQUENCYVIBRATIONThe engine exciting force was determined using Souma‟s method, and the vibration in each part of the engine was calculated by adding the exciting force. So far, however, the calculated data has not been much identified with the actual measurement. Therefore, the accuracy of the actual measurement is improved. In the surface vibration of the engine, the low-frequency vibration, which causes the idling vibration, and the high-frequency vibration, which causes noise, are mixed. When the mixed vibration is measured with a piezo element acceleration pickup, the high-frequency order is emphasized and the target low-frequency order becomes relatively small. For example, the measured acceleration to time waveform for the vertical vibration in the right engine foot is shown in Figure 4.In this paper, a strain gage acceleration pickup, which measures force acting on the inner weight by strain, is used. This device, which is larger than a piezo element acceleration pickup, is more sensitive to the acceleration. Besides, silicon oil is filled inside to protect the detecting parts in this device, which mechanically blocks off the high-frequency order. The measured acceleration to time waveform for the vertical vibration with the device is shown in Figure 5. Compared with Figure 4, Figure 5 shows only the low-frequency order although the same area was measured. In this way, the high-frequency order is blocked off, which results in the higher sensitivity with the device. This time, the device, which measures the acceleration ranging from 0 to 20m/s2,was used. This device is easily calibrated using G-forces because it has the higher sensitivity. When a piezo element acceleration pickup was used, the differences between the calculation and the experiment were 20-40% in the main order of the vibration, and a few times in other orders. Therefore, the principle of Souma‟s method using a piezo element accelerationpickup has been in doubt. However, the data of the experiment and the calculation has been identified as shown in Figure 2 and 3 since a strain gage acceleration pickup, which hasENTIRE VEHICLE MODELFigure 6 shows the body model. Interior and exterior equipments such as doors and seat are added in the form of 85 mass points to the main structure modeling detailed with sheet metal finite elements. The grid points are 61,912. Figure 7 shows the model where a frame, a suspension, and an engine are combined, and a fuel tank and a bumper is added in the form of concentrated mass. The grid points are 39,262.Combining the models shown in Figure 6 and 7 using cabmount makes the entire vehicle model. Total grid points mounts to 101,174. The calculation time is 3,293 seconds using IBMSP2, MSC/NASTRAN Version 70.5.2. The calculating method is package calculation. If the model becomes on larger scale, the model must be calculated by the block structure.Figure 8 shows the frequency response function, indicating the responses of the frame with the right back engine mount after exciting the driver‟s seat rai l. In the frequency ranging from 20 to 30 Hz, which is required for the analysis, the data of the experiment is qualitatively identified with that of the calculation.Fig. 5 Measurement with strain gage acceleration pickup Fig. 6 Body modeCORRELATION ANALYSIS OF THE MODESFrom the viewpoint of vibration characteristics, it can be considered that an entire vehicle is insulated by the engine mount and the cabmount, which have relatively small spring constants, although the insulation is not complete. When the entire vehicle is divided into block structures by each insulating mount and suspension, the body has 4 block structures:(1) Block where interior equipment is added in the form of concentrated mass to the body as shown in Figure 6, which is described as “body”, hereafter.(2) Block where the fuel tank and the bumper are added in the from of concentratedmass to the frame as shown in Figure 7, which is described as “frame,” hereafter.(3) Power plant(4) SuspensionAmong the above block structures, (1) body and (2) frame have the natural frequency around 24 Hz in the idling vibration. The vibration characteristics for the body, the frame and the entire vehicle model are compared and investigated.COMPARISON OF NATURAL FREQUENCYFigure 9 shows the distribution of the natural vibration frequency in each block structure and in the vehicle condition. The frame has 17 natural modes below 50Hz. In Figure 7, the model mounting a power plant and a suspension on the frame, is called Y chassis, which has 35 natural modes below 50 Hz. Y chassis makes the entire vehicle model by mounting the body, which has 94 natural modes below 50 Hz.When the number of natural modes of Y chassis is added to 61 natural modes of the body, total number of the modes amounts to 96. The number of the natural modes of the entire vehicle model (94) is less than the above total number by 2 modes. This is because 2 natural modes became above 50 Hz by combining Y chassis and the body, as the result of analyzing the mode correlation described later.Fig. 9 Natural modes in frequency domain附录B方程式赛车多连杆式后悬架结构模态分析摘要建立全车架结构SUV的有限元模型,用来评价车辆的怠速震动特性。
汽车悬架的发展历程外文文献翻译、中英文翻译、外文翻译
The development of automobile suspensionAutomobile suspension system is a connecting structure system between the body and frame and wheels, and the structural system includes shock absorbers, suspension springs, anti roll bars, suspension side beam, lower control arm, longitudinal bar, steering knuckle arm, rubber bushing and connecting rod etc.. When the car on the road because of the ground change by the vibration and impact, the impact strength of one part by tire absorption, but mostly rely on suspension tire and the body to absorb. In the running process of the automobile suspension, the role is to connect the axle and the frame flexibility, slow moving vehicle impact force caused by uneven pavement, ensure the ride comfort and the goods, due to the rapid decay caused by the vibration of elastic system, vertical, longitudinal and lateral transfer to force and torque, and play a leading role. The wheel according to a certain trajectory relative to body movement. Suspension is one of the most important parts of modern automobile. The typical suspension structure is made up of elastic element, guide mechanism and shock absorber, etc., and there are buffer blocks, transverse stabilizer bars and so on. The elastic element is composed of a steel plate spring, an air spring, a spiral spring and a torsion bar spring, etc. the modern car suspension adopts a spiral spring and a torsion bar spring.Types and working principle of suspensionAccording to the suspension damping and stiffness changes with the change of driving conditions, can be divided into passive suspension, semi-active suspension and active suspension, semi-active suspension can also be divided into two types of damping and variable type. The traditional system of suspension stiffness and damping coefficient is selected according to the experience design and optimization design method, once selected, in the course of the vehicle, it can not be adjusted, so the damping performance limits further enhance, the suspension has become passive suspension. In order to overcome the defects of passive suspension, the concept of active suspension was proposed in 1960s, which is composed of active or passive components. It is a closed loop control system, according to the movement of the vehicle and the state of the road to take the initiative to respond to restrain the movement of the body, so that the suspension is always in the best state of shock.Therefore, the characteristics of active suspension is to adapt to the changes of the external input or the vehicle itself. So the system must be active. Semi active suspension is composed of passive but controllable damping elements. In the vehicle suspension, in addition to absorbing and storing energy, the elastic element also has to bear the weight and the load of the vehicle body. Therefore, the semi-active suspension does not consider changing the stiffness of the suspension. Because of the semi active suspension structure is simple, in the work, almost does not consume the vehicle power, but also can get similar performance with the active suspension, it is widely used. Due to random road input, control of vehicle suspension damping belongs to adaptive control system is designed, changes occur in a wide range of input or interference, adaptive environment, adjusting the system parameters, so that the output can be controlled effectively, meet the design requirements. It is different from the general feedback control system because it deals with the feedback information with "uncertainty". The adaptive control system according to the principle of different, can be divided into tuning regulator and model reference adaptive control system of two categories, because it is difficult to establish a precise "vehicle bottom" system model, the active suspension, the use of self correction regulator. Although there are many kinds of modern automobile, the structure difference is big, but it is generally composed of elastic element, damping element and guiding component. The working principle is that when the automobile tire is impacted, the elastic element is used for buffering the impact to prevent damage to the automobile components and personnel. However, the elastic parts will be affected by the growth time of sustained vibration, easy to make the driver fatigue. Therefore, the vibration damping elements should be quickly damped vibration. When the wheel is hit by the impact, it should be consistent with the trajectory of certain requirements, otherwise it will reduce the ride comfort and handling stability of the vehicle. The direction of the steering component must be controlled at the same time.The history and present situation of suspensionIn the carriage appeared, in order to ride more comfortable, humans began to ride the suspension of a leaf spring tireless exploration. In 1776, the leaf spring of the carriage was patented, and it was used until 1930s. After the birth of the car, with the in-depth study of thesuspension, the torsion spring, gas spring, rubber spring, leaf spring, etc.. In 1934, the world's first passive suspension composed of helical springs. The parameters of the passive suspension are determined according to the experience or the method of optimal design. It is a series of road compromise, it is difficult to adapt to a variety of complex road conditions, the effect of poor damping. In order to overcome this defect, the nonlinear stiffness spring and the adjustment of the height of the body are adopted. Although the results are satisfactory, the disadvantages of passive suspension can not be eliminated. The passive suspension is mainly used in low-grade cars, the front suspension of modern cars generally use the Mcpherson suspension with stabilizer bar, choose more after the suspension, the main composite longitudinal swing arm suspension and multi link suspension. Semi active suspension research began in 1973, first proposed by D.A.Crosby and D.C.Karnopp. Semi active suspension is mainly used to change the damping of suspension. The working principle is as follows: according to the control law of the spring, the damping force or stiffness of the spring can be adjusted according to the feedback signal of the spring mass relative to the wheel speed response and acceleration response. The semi-active suspension is similar to the passive suspension, but its damping or stiffness coefficient can be adjusted according to the running state, which is similar to that of the active suspension. A type of semi active suspension damping is divided into several stages, the damping level by the driver according to the "road" or by the sensor signal automatic selection; stepless semi-active suspension based on road conditions and vehicle driving state of suspension within a few milliseconds from the minimum to the stepless speed regulation. Due to the relatively simple structure of the semi-active suspension, the work does not need to consume the power of the vehicle, and can obtain the same performance with the active suspension, has a broad space for development. With the continuous development of road traffic, vehicle speed has been greatly improved, the passive suspension has gradually become the bottleneck of improving the performance of vehicle, so people can develop both comfort and handling stability of active suspension. The concept of active suspension is the first proposed in the suspension design of General Motors Corporation in 1954. On the basis of the passive suspension, it can increase the stiffness and damping of the control device, so that the suspension of the car on any road to maintain thebest running state. The control device is composed of measuring system, feedback control system and energy system. In 1980s, the world's leading automobile companies and manufacturers competing to develop and develop this suspension. Mercedes Benz, V olvo, Lotts, TOYOTA, etc. in the car on a more successful test. Equipped with active suspension of the car, in the bad road high speed, the body is very stable, the tire noise is small, steering and braking body to maintain the level of. The utility model is characterized in that the ride is very comfortable, but the structure is complex, the energy consumption is high, the cost is high, and the reliability is different.Due to various reasons, most of China's automotive passive suspension. In the study of semi-active and active suspension started late, with a large gap between foreign countries. In the western developed countries, semi active suspension in the late 1980s tends to mature, Ford Motor Co and Nissan first in the car application, and achieved good results. Although the active suspension has been put forward earlier, it is difficult to make a big breakthrough because of its complicated control and many subjects. Into 1990s, throwing only applies to the large amount of luxury cars. There is no report of domestic automotive products using this technology, only a few research institutions such as Beijing Institute of Technology and Tongji University to study the active suspension.Development trend of suspensionDue to the requirements of ride comfort and handling stability, a safe, intelligent and clean green intelligent suspension will be the future development trend of automobile suspension. Passive suspension is a traditional mechanical mechanism, stiffness and damping are not adjustable, according to the theory of random vibration, it can only ensure that the specific road conditions to achieve better results. However, its theory is mature, simple structure, reliable performance, relatively low cost and does not require additional energy, which is the most widely used. In our country, there is still a high research value. Study on passive suspension performance mainly in three aspects: through analyzing the stress of the car after the establishment of mathematical model, the optimal parameters and then use the computer simulation technology or finite element method for suspension; damper of variable stiffness spring and variable damping suspension, make good operation in most of the roadstudy; guiding mechanism, make the car suspension to meet the comfortUnder the premise, the stability has improved greatly. The research of semi-active suspension is focused on two aspects: the research of execution strategy and the research of actuator. There are two kinds of damping adjustable shock absorber, one is to adjust the damping by changing the size of the orifice. The size of the throttle hole in general through the solenoid valve or stepper motor for a level or stepless adjustment, this method is more expensive, complex structure. The damping coefficient can be changed by changing the viscosity of the damping fluid, which has the characteristics of simple structure, low cost, no noise and shock. The research of active suspension is also focused on two aspects: reliability; actuator. The active suspension with a large number of sensors, MCU, input and output circuit and the interface, because of more components, reduces the reliability of the suspension, therefore, increase the degree of integration of elements, is an impassable stage. The actuator is mainly used to replace the hydraulic components of electric devices. The linear servo motor and permanent magnet DC linear servo motor in electric power system have many advantages, which will replace the hydraulic actuator in the future. Based on the principle of electromagnetic energy storage and the self tuning controller of parameter estimation, a high performance and low power electromagnetic active adaptive suspension can be designed. With the development of the traffic, the highway is improving gradually, and the speed of the car is faster and faster. The automobile suspension system to support force, the road acting on the wheel longitudinal force and lateral force and the reaction force caused by the torque is transmitted to the frame, in order to ensure the normal running of the vehicle, therefore has a crucial influence on the vehicle driving vehicle suspension system, dynamic simulation of the automobile suspension system is very high status in vehicle design and development. In the field of automobile engineering, simulation software can avoid duplication of manufacturing parts and prototype in product development process, resources, reduce the waste of time and money, a study on the power can be better kinematics in automotive engineering field using simulation software. Foreign countries have developed IMP, ADAMS and DAMN simulation software for the field of automotive kinematics.ConclusionWith Solidworks, Pro/E, CATIA, UG, ADAMS, ANSYS and other CAD/CAE software development, plays a key role in the research and development of automobile suspension, through finite element method, computer simulation technology, reduce the enterprise cost of research and development of computer optimization design method, shorten the development cycle. Generally speaking, the active suspension has good damping effect and superior performance, and solves the contradiction of ride comfort and handling stability. But the component cost is higher, work needs more energy, vehicle quality also increased, so the active suspension will greatly increase the cost and energy consumption; the damping performance of the semi-active suspension close to active suspension, steering stability is better than passive suspension. It is the only way for the development of semi-active suspension that the performance is reliable, the adjustable damping damper and the simple and effective control strategy. The performance of passive suspension is the worst, but it has the lowest cost and no need to consume energy. Passive suspension in a certain period of time will be the most widely used suspension system, by further optimizing the suspension structure and parameters can continue to improve the suspension performance.汽车悬架的发展历程汽车的悬架系统是指车身、车架和车轮之间的一个连接结构系统,而这个结构系统包含了避震器、悬架弹簧、防倾杆、悬吊副梁、下控臂、纵向杆、转向节臂、橡皮衬套和连杆等部件。
汽车车辆类悬架和框架设计外文文献翻译
附录AFormula SAE is a student competition sponsored by Society of Automotive Engineers (SAE), were students design, build, and compete with a small formula style race car. The basis of the competition is that a fictitious company has contracted a group of engineers to build a small formula car. Since the car is intended for the weekend autocross racer, the company has set a maximum price of $8,500. The race car is also limited to a single 610cc displacement engine with a single inlet restrictor. Other major rules require that the car must have a suspension system with a minimum wheel travel of 50mm and a wheelbase greater than 1524mm. The remainder of the rules define safety requirements such as side impact protection .The competition is separated into static and dynamic events. The static events include the cost nalysis, sales presentation, and engineering design. The dynamic portions of the competition are the 15.25 m diameter skid-pad, 91.44 m acceleration event, 0.8 km autocross, 44 km endurance race, and fuel economy.The FSAE competition has been established to provide an educational experience for college students that is analogous to the type of projects they will face in the work force. To participate in FSAE, student groups work with a project from the abstract design until it is completed. The aspects of engineering design, team work, project management, and finance have been incorporated into the basic rules of Formula SAE.This paper is intended to cover some of the basic concepts of suspension and frame design and also highlights the approach UM-Rolla used when designing their 1996 suspension and frame. The suspension section addresses the basic design parameters and presents specific examples. Next, the frame section discusses how to achieve a compromise with the FSAE design constraints. Finally, the design section gives a brief overview of the design methodology used by UM-Rolla for the 1996 race car.1.Suspension GeometryFSAE suspensions operate in a narrow realm of vehicle dynamics mainly due to the limited cornering speeds which are governed by the racetrack size. Therefore, FSAE suspension design should focus on the constraints of the competition. Forexample, vehicle track width and wheelbase are factors governing the success of the car's handling characteristics. These two dimensions not only influence weight transfer, but they also affect the turning radius.Not only do the kinematics have to be considered for FSAE suspension, but the components must also be reasonably priced for the cost analysis and marketable for the sales presentation. For example, inboard suspension could be a more marketable design, while outboard suspension might cost less and be easier to manufacture.The suspension geometry section concentrates on some of the basic areas of suspension design and highlights what the UM-Rolla design team selected for their 1996 race car suspension geometry. UM-Rolla chose to use a four wheel independent suspension system with push rod actuated inboard coil over shocks. This decision was mainly because of packaging constraints. Furthermore, the appearance of inboard suspension was considered important for both the design judging and the sales presentation because of its similarity to modern race cars.Also, this section of the paper was written with short-long arm suspension systems in mind. However, many of the concepts are valid for other suspension types.2.Track Width and WheelbaseThe definition of track width is the distance between the right and left wheel centerlines which is illustrated in Figure 1. This dimension is important for cornering since it resists theFigure 1. Track Widthoverturning moment due to the inertia force at the center of gravity (CG) and the lateral force at the tires . For the designer, track width is important since it is oneUpper Ball Joint Track Low Ball Joint Upper Control UpperControlcomponent that affects the amount of lateral weight transfer . Also, the designers must know the track width before kinematic analysis of the suspension geometry can begin.When selecting the track width, the front and rear track widths do not necessarily have to be the same. For example, track width is typically wider in the front for a rear wheel drive race car. This design concept is used to increase rear traction during corner exit by reducing the amount of body roll resisted by the rear tires relative to the front tires. Based on the corner speeds and horsepower to weight ratio of FSAE cars, this concept should be considered by the designer.The wheelbase also needs to be determined. Wheelbase is defined as the distance between the front and rear axle centerlines, and also influences weight transfer, but in the longitudinal direction. Except for anti-dive and anti-squat characteristics, the wheelbase relative to the CG location does not have a large effect on the kinematics of the suspension system. However, the wheelbase should be determined early in the design process since the wheelbase has a large influence on the packaging of components.For track width and wheelbase starting points, the designers should research the opposition's dimensions to serve as a baseline for their own calculations. FSAE car specifications for the competing teams, including track width and wheelbase, are available in the event program published by SAE.The 1996 design team selected a 1727 mm wheelbase, 1270 mm front track width, and a 1219 mm rear track width, which were based on previous UM-Rolla cars. Although this wheelbase was adequate for the FSAE competition size courses, the UM-Rolla design team has decided to increase the wheelbase for the next car to 1854.2 mm. This increase in wheelbase is an attempt to improve stability for high speed corner entry at the competition.3.Tire and WheelAfter track width and wheelbase considerations have been addressed, tire and wheel selection is the next step in the design process. Since the tire is important to the handling of the vehicle, the design team should thoroughly investigate the tire sizes and compounds available. The tire size is important at this stage of the design since the height of the tire must be known before the geometry can be determined. For example, the tire height for a given wheel diameter determines how close the lower ball joint can be to the ground if packaged inside the wheel.Tire Size - The designers should be aware that the number of tire sizes offeredfor a given wheel diameter is limited. Therefore, considering the importance of the tire to handling, the tire selection process should be a methodical process. Since the amount of tire on the ground has a large influence on grip, it is sometimes desirable to use wide tires for increased traction. However, it is important to remember that wide tires add rotating mass which must be accelerated by a restricted FSAE engine. This added mass might be more detrimental to the overall performance than the increase in traction from the wider tires. Not only does a wider tire add mass, but it also increases the amount of rubber that must be heated. Since racing tires are designed to operate most efficiently in a specific temperature range, this added material may prevent the tires from reaching the optimum temperature range . The UM-Rolla team used tires for the 1996 competition that were designed to work most efficiently at a minimum of 71°.During the selection process the designers must consider how the tires will influence the performance of the entire package. For example, the weather conditions for the FSAE dynamic events might determine which tire compound and tire size should be used for the competition. Another important consideration is the price of the tires since the cost can be a large portion of a team's budget.For the 1996 competition, UM-Rolla selected a 20 by 6-13 racing tire for both the front and rear of the car. Because of the low vehicle mass, a narrow tire was selected so tire temperatures would be greater than previous UM-Rolla designs. This tire selection increased the operating temperature from 48o to 60oC. For the competition, the weather was predicted to be cool, so the team brought a set of hard and soft compound tires. The team chose to use the harder compound since the weather for the endurance was predicted to be clear and warm.Wheel Selection - Once a decision has been made as to which tire sizes to use, the wheel selection should be next. Usually, the wheel dimensions are fixed and allow for little modification. Therefore, it is important to have some design goals in mind before investing in wheels. Generally, the upright, brake caliper, and rotor are placed inside the wheel which requires wheel offset for clearance. It is usually easier to design the suspension geometry if the wheel profile is known. For example, the ball joint location is limited to the area defined by the wheel profile. Some packaging constraints are shown in Figure 2.Other considerations for wheel selection include: cost, availability, bolt circle, and weight. For example, three-piece rims, althoughexpensive, have the distinct advantage of offering many offsets and profiles that can be changed during the design process .Figure 2. 1996 Front SuspensionUM-Rolla designed the 1996 suspension geometry around a wheel profile from a previous car and then acquired a set of three-piece rims to meet the design specifications. All four wheels selected for the 1996 competition were size 6 by 13. This wheel selection allowed for tire rotations, reduced cost, and a wide selection of tire sizes, compounds, and manufacturers.4.GeometryThe designer can now set some desired parameters for the suspension system. These usually include camber gain, roll center placement, and scrub radius. The choice of these parameters should be based on how the vehicle is expected to perform. By visualizing the attitude of the car in a corner, the suspension can be designed to keep as much tire on the ground as possible. For example, the body roll and suspension travel on the skid pad determines, to a certain extent, how much camber gain is required for optimum cornering. The amount of chassis roll can be determined from roll stiffness while the amount of suspension travel is a function of weight transfer and wheel rates.Once a decision has been made about these basic parameters, the suspension must be modeled to obtain the desired effects. Before the modeling can begin, the ball joint locations, inner control arm pivot points, and track width must be known.The easiest way to model the geometry is with a kinematics computer program since the point locations can be easily modified for immediate inspection of their influence on the geometry. Should a dedicated kinematics computer program not be available, then a CAD program can be used simply by redrawing the suspension as the points are moved.When designing the geometry, it is important to keep in mind that designing is an iterative process and that compromises will be inevitable. For instance, the desired scrub radius might not be possible because of packaging constraints. When modelingthe suspension, the designers should not aimlessly modify points without first thinking through the results. For example, the designer should visualize how the wheel will camber relative to the chassis when making the lower A-arm four times longer than the upper A-arm. One method that can be used to visualize the results is the instant center location for the wheel relative to the chassis. Another method is to use the arcs that the ball joints circumscribe relative to the chassis. For a complete explanation for determining suspension point locations from instant center locations refer to Milliken .Scrub Radius, KPI, and Caster - The scrub radius, or kingpin offset, is the distance between the centerline of the wheel and the intersection of the line defined by the ball joints, or the steering axis, with the ground plane which is illustrated in Figure 2. Scrub radius is considered positive when the steering axis intersects the ground to the inside of the wheel centerline. The amount of scrub radius should be kept small since it can cause excessive steering forces . However, some positive scrub radius is desirable since it will provide feedback through the steering wheel for the driver .Kingpin inclination (KPI) is viewed from the front of the vehicle and is the angle between the steering axis and the wheel centerline . To reduce scrub radius, KPI can be incorporated into the suspension design if packaging of the ball joints near the centerline of the wheel is not feasible. Scrub radius can be reduced with KPI by designing the steering axis so that it will intersect the ground plane closer to the wheel centerline. The drawback of excessive KPI, however, is that the outside wheel, when turned, cambers positively thereby pulling part of the tire off of the ground. However, static camber or positive caster can be used to counteract the positive camber gain associated with KPI.Caster is the angle of the steering axis when viewed from the side of the car and is considered positive when the steering axis is tilted towards the rear of the vehicle . With positive caster, the outside wheel in a corner will camber negatively thereby helping to offset the positive camber associated with KPI and body roll. Caster also causes the wheels to rise or fall as the wheel rotates about the steering axis which transfers weight diagonally across the chassis . Caster angle is also beneficial since it will provide feedback to the driver about cornering forces .UM-Rolla's suspension design team chose a scrub radius of 9.5 mm, zero degrees of KPI, and 4 degrees of caster. This design required the ball joints to be placed near the centerline of the wheel,which required numerous clearance checks in the solid modeling program.Roll Center - Once the basic parameters have been determined, the kinematics of the system can be resolved. Kinematic analysis includes instant center analysis for both sets of the wheels relative to the chassis and also for the chassis relative to the ground as shown in Figure 3. The points labeled IC are the instant centers for the wheels relative to the chassis. The other instant center in Figure 3, the roll center, is the point that the chassis pivots about relative to the ground . The front and rear roll centers define an axis that the chassis will pivot around during cornering. Since the CG is above the roll axis for most race cars, the inertia force associated with cornering creates a torque about the roll center. This torque causes the chassis to roll towards the outside of the corner. Ideally, the amount of chassis roll would be small so that the springs and anti-roll bars used could be a low rate for added tire compliance . However, for a small overturning moment, the CG must be close to the roll axis. This would indicate that the roll center would have to be relatively high to be near the CG. Unfortunately, if the roll center is anywhere above or below the ground plane, a "jacking" force will be applied to the chassis during cornering forces . For example, if the roll center is above ground, this "jacking" force causes the suspension to drop relative to the chassis. Suspension droop is usually undesirable since, depending on the suspension design, it can cause positive camber which can reduce the amount of tire on the ground. Conversely, if the roll center is below the ground plane, the suspension goes into bump, or raises relative to the chassis, when lateral forces are applied to the tires. Therefore, it is more desirable to have the roll center close to the ground plane to reduce the amount of chassis vertical movement due to lateral forces .Figure 3. Front Roll CenterSince the roll center is an instant center, it is important to remember that the roll center will move with suspension travel. Therefore, the design team must check the migration of the roll center to ensure that the "jacking" forces and overturning moments follow a relatively linear path for predictable handling . For example, if the roll center crosses the ground plane for any reason during cornering, then the wheels will raise or drop relative to the chassis which might cause inconstant handling.Theroll center is 35.6 mm below ground in the front and 35.6 mm above ground in the rear for UM-Rolla's 1996 car. Since none of the previous UM-Rolla cars had below ground roll centers, the selection of the 1996 points was basically a test to understand how the below ground roll center affected the handling. Because of the large roll moment, the team designed enough camber gain into the suspension to compensate for body roll associated with soft springs and no anti-roll bar. The team was very happy with the handling but decided, for the next car, to have both roll centers above ground for a direct comparison between both designs.Camber - Camber is the angle of the wheel plane from the vertical and is considered to be a negative angle when the top of the wheel is tilted towards the centerline of the vehicle. Camber is adjusted by tilting the steering axis from the vertical which is usually done by adjusting the ball joint locations. Because the amount of tire on the ground is affected by camber angle, camber should be easily adjustable so that the suspension can be tuned for maximum cornering. For example, the amount of camber needed for the small skid pad might not be the same for the sweeping corners in the endurance event.The maximum cornering force the tire can produce will occur at some negative camber angle . However, camber angle can change as the wheel moves through suspension travel and as the wheel turns about the steering axis. Because of this change, the suspension system must be designed to compensate or complement the camber angle change associated with chassis and wheel movements so that maximum cornering forces are produced.The amount of camber compensation or gain for vertical wheel movement is determined by the control arm configuration. Camber gain is usually obtained by having different length upper and lower control arms. By using different length control arms, the ball joints will move through different arcs relative to the chassis. The angle of the control arms relative to each other also influence the amount of camber gain. Because camber gain is a function of link geometry, the amount of gain does not have to be the same for both droop and bump. For example, the suspension design might require the wheels to camber one degree per 25mm of droop versus negative two degrees per 25mm of bump.Static camber can be added to compensate for body roll, however, the added camber might be detrimental to other aspects of handling. For example, too much static camber can reduce the amount of tire on the ground, thereby affecting straightline braking and accelerating. Similarly, too much camber gain during suspension travel can cause part of the tire to loose contact with the ground.Caster angle also adds to the overall camber gain when the wheels are turned. For positive caster, the outside wheel in a turn will camber negatively, while the inside wheel cambers positively. The amount of camber gain caused by caster is minimal if the wheels only turn a few degrees. However, FSAE cars can use caster angle to increase the camber gain for the tight corners at the FSAE competition.UM-Rolla designed for a relatively large amount of camber gain since anti roll bars were not used in the 1996 suspension design. The use of low wheel rates with a large roll moment required the suspension to compensate for the positive camber induced by chassis roll and suspension travel. The camber gain for UM-Rolla's 1996 car was from both the caster angle and the control arm configuration.5.Steering SystemThe steering geometry has a large influence on the handling characteristics of the vehicle. For example, if the system is not properly designed, then the wheels can unexpectedly toe in or out during suspension travel. This toe change is referred to as bump steer which is described in detail in both references . Bump steer is basically undesirable since the car changes direction when the driver does not expect the change .Ackermann steering must also be considered during the design process. Ackermann steering occurs when the outside wheel turns less than the inside wheel. This is possible since the amount of steering angle for each wheel is determined by the steering geometry. Reverse or anti-Ackermann occurs when the outside wheel turns more than the inside wheel during cornering .During a turn, the inside wheel travels around a smaller geometric radius than the outside wheel. Ackermann steering can be used so that the wheels travel about their corresponding radii, theoretically, eliminating tire scrub. However, designing for precise Ackermann steering might not provide the best handling since tire slip angles influence the actual turning radius . The designer must decide, based on the requirements, if the steering system design will include Ackermann geometry.UM-Rolla placed the rack and pinion in front of the axle centerline near the lower control arms because of packaging constraints. This placement required extra room in the frame design since the driver had to straddle the steering column. Afterbuilding a test car that was hard to steer because of a half a turn lock to lock system, the 1996 steering system was designed to be one turn lock to lock. This was accomplished by changing the rack and pinion ratio instead of increasing the steering arm length because of packaging constraints. The system specifications for the 1996 car are: 76mm steering arms, 250mm diameter steering wheel, and 51mm of rack travel per one pinion revolution. These specifications were retained for the next race car design because of the handling characteristics. The 1996 UM-Rolla design has a small amount of anti-Ackermann due to packaging.FSAE suspension not only has to be competitive on the racetrack, but the suspension must also perform well in the static events. For the dynamic events, the designers should concentrate on the geometry so that most of the tire will stay in contact with the ground for all normal driving situations: braking, accelerating, and cornering. The suspension system must also be designed so that it is easy to manufacture and is reasonably priced for the cost analysis. To reduce the cost and complexity of the 1996 race car, UM-Rolla designed the system so that the wheels, hubs, and bearings were the same for each corner of the car.Designing the suspension geometry is only a small part of building a vehicle. A well engineered suspension system does not automatically make a fast race car. Although this paper has concentrated on the design aspect, development is just as important to the success of the package. Because the design process must take place within a given time constraint, the first suspension design might not provide the best handling. It is not uncommon to make design changes after the car is completed. It is more important for FSAE teams to compromise the overall design so that the car can be completed and tested prior to competition.6.FrameThe purpose of the frame is to rigidly connect the front and rear suspension while providing attachment points for the different systems of the car . Relative motion between the front and rear suspension attachment points can cause inconsistent handling . The frame must also provide attachment points which are not going to yield within the car's performance envelope.There are many different styles of frames; space frame, monocoque, and ladder are examples of race car frames. The most popular style for FSAE is the tubular space frame. Space frames are a series of tubes which are joined together to form a structurethat connects all of the necessary components together. However, most of the concepts and theories can be applied to other chassis designs.Figure 4. UM-Rolla's 1996 Frame Design7.StiffnessThe suspension is designed with the goal of keeping all four tires flat on the ground throughout the performance range of the vehicle. Generally, suspension systems are designed under the assumption that the frame is a rigid body. For example, undesirable changes in camber and toe can occur if the frame lacks stiffness. Superimposed images of a frame subjected to a torsional load and an undeflected frame and can be seen in Figure 5.Figure 5. Chassis DeflectionUM-Rolla has found that in most cases, a stiff chassis will not have a problem with yielding. However, some care should be taken to ensure that the attachment points of the frame do not yield when subjected to design loads. For example, the engine mounts should be made stiff enough to reduce the possibility of failure.Torsional Stiffness - Torsional stiffness is the resistance of the frame to torsional loads . UM-Rolla used FEA to analyze the torsional stiffness of the 1996 chassis. The solution of the simple rod and beam element model for the frame was roughly 2200 foot pounds per degree of deflection. The 1996 frame weighed approximately 27kg, which UM-Rolla believes is heavier than needed for a two day racing series. However, some extra structure was added to the frame to increase its safety. Also, the drivetrainmounts were significantly strengthened so that the car would be able to serve as a driver training tool for several semesters.As the 1996 frame evolved, the stiffness to weight ratios of different designs were compared. A chassis can be made extremely stiff by adding significant amounts of material to the frame. However, this additional material might degrade the performance of the car because of the added mass.Obviously, torsional rigidity is not the only measurement for analyzing the stiffness of a chassis. Bending stiffness can also be used to analyze the efficiency of a frame design. However, bending stiffness is not as important as torsional stiffness because deflection due to bending will not affect wheel loads . Because the design time is severely limited in FSAE, UM-Rolla has found that a torsional analysis is adequate to determine the relative stiffness of different frame designs.Triangulation - Triangulation can be used to increase the torsional stiffness of a frame, since a triangle is the simplest form which is always a structure and not a mechanism. Obviously, a frame which is a structure will be torsionally stiffer than a mechanism . Therefore, an effort should be made to triangulate the chassis as much as possible.Visualizing the frame as a collection of rods which are connected by pin joints can help frame designers locate the mechanisms in a design . Designers can also evaluate their frame by checking to see if each pin jointed node contains at least three rods which complement the load path.UM-Rolla chose to use thin wall steel tubing for the 1996 frame design. This required significant triangulation of the frame, since thin wall tubing performs very well in tension and compression but poorly in bending. The components which produce significant amounts of force, for example the engine and suspension, were attached to the frame at a triangulated point.Figure 6. Frame Triangulation(Frame, Side View)Previous UM-Rolla frames have lacked adequate triangulation for highly loaded components. These components were attached to the frame with load bearing tabs which were welded at the midpoint of a single section of tubing. As expected, thistube bent like a simply supported beam and caused unwanted movement of the attached component. Although these designs worked for the duration of the competition, they invariably failed by fracturing the tube or breaking the tab. For the 1996 car, all of the highly loaded components were attached to triangulated points.Area Moment of Inertia - The area moment of inertia has a large influence on the stiffness of a structure. Therefore, the farther material is from the axis of twist the stiffer the frame will be in bending and torsion. This concept is implemented by adding structural side pods to the basic frame.Figure 7. Structural Sidepods(Frame Top View)Figure 7 shows the triangulated side pods which were used to increase the torsional rigidity of the 1996 frame. This material also increased the side impact protection. The sidepods add structure as far from the centerline of the chassis as possible which increases the area moment of inertia between the front and rear suspensions. Most of the successful FSAE cars have structural side pods for safety and increased torsional stiffness.In addition to using the sidepods to increase the stiffness of the chassis, UM-Rolla's 1996 entry used the roll hoop and down tubes to increase the rigidity of the frame. The 1997 FSAE rules state that the tubes from the top of the roll hoops to the base of the frame have to be 0.049" wall when fabricated from 4130 steel . Because these tubes are stiffer than 0.035" wall tubing, the frame stiffness can be substantially increased by properly placing the roll hoop tubes.8.Load PathDuring the design process, it is important to consider how loads are passed into the frame. A "Load Path" describes the path through which forces are dissipated into the frame. For example, Figure 8 shows how the vertical load generated by the weight on the wheel will travel through the upright, push rod, rocker, coil-over shock and into the structure of the frame. Of course, to properly investigate the forces involved, a freebody diagram for each component would have to be drawn. Nevertheless, this。
中英文文献翻译-汽车悬架系统
附录AThe automotive vehicle suspension system frame (or Unibody) and axle (or wheel) power transmission connection between all devices in general. Its function is to act on the road wheels on the vertical force (support force), the vertical reaction force (traction and braking) and lateral reaction force and the torque reaction force caused by the transfer to the frame (or Unibody) on, in order to ensure the normal running car. Therefore, the suspension system performance and quality performance for the vehicle plays an important role. This paper suspension systems for passenger cars and trucks in the widely used leaf spring design calculation method for the in-depth analysis and research.The article on the current variety of automotive leaf spring design calculation method of intensive analysis and research, summed up the characteristics of various calculation methods, limitations and application. Automotive leaf spring from the elastic component in addition to the role, but also and play the guiding role, and multi-chip friction between the spring damping system also played. As the leaf spring structure is simple, use and maintenance, and easy maintenance, long leaf springs are widely used in the car. Usually the new car design, according to the layout of a given space vehicle, axle load full load minus the estimated quality of non-sprung mass, obtained in each pair of spring bearing on the quality. Generally before the rear axle, wheels, brake drums and steering knuckle, transmission shaft, steering assembly, such as non-vertical rod sprung mass. If the layout of the axle above the leaf spring, spring 3 / 4 the quality of the non-sprung mass, the next set spring, 1 / 4 non-sprung mass spring mass models based on different requirements, general arrangement is given by the straight length of spring control size.In the arrangement possible, try to increase the length of the spring, mainly to consider the following reasons. As the spring stiffness and is inversely proportional to the cube of the length of the spring, so from the perspective of improving vehicle ride comfort, hope springs length longer good. In the spring stiffness of the same case, the long wheel up and down in the spring, the spring from the two ears changes the volume is relatively small, the front suspension, the caster angle change is small, in favor of auto driving stability. Increase the length of the spring can reduce stress andstress amplitude spring working to improve spring life. Can be used to increase the length of the spring reed thick spring, thereby reducing the number of springs and spring reed thick volume ear piece to improve the strength of the main vehicle sprung mass vibration system with quality components to evaluate the natural frequency of vehicle ride comfort important parameters. Suspension design based on vehicle ride comfort requirements, should be given an empty car, fully loaded, front and rear suspension frequency range. If you know the frequency, you can find the suspension static deflection. Select the suspension static deflection, the hope after the suspension static deflection is less than the front suspension static deflection, and the best value close to two vehicles in order to prevent uneven roads often hit the buffer block, suspension design must be given adequate deflection value. Suspension dynamic deflection and car usage and the value of the static deflection due to ride height, suspension travel and dynamic properties of steel spring guide are all fully loaded car with a high arc, and therefore the arc spring loaded high-value should be based on vehicle and suspension performance requirements are given the appropriate value. Some vehicles get good handling and stability, full arc high negative value.附录B汽车悬架系统是汽车车架(或承载式车身)与车桥(或车轮)之间的一切传力连接装置的总称。
汽车悬架如何工作——毕业设计外文翻译(中英文翻译、文献翻译)
附录A 译文汽车悬架如何工作By William HarrisUniversity of Michigan当人们考虑汽车性能的时候,他们通常认为是马力,扭矩和零到60的加速时间。
但是,如果司机无法控制汽车,由一个活塞发动机产生的功率都是无用的。
这就是为什么汽车的工程师开始将注意力转向悬挂系统,尽快为他们几乎已经掌握了四冲程内燃机。
双横臂独立悬架的本田雅阁轿跑车2005年汽车悬架的工作是尽量在轮胎和路面之间提供良好的操纵稳定性,并确保乘客的舒适度。
在这篇文章中,我们将探讨汽车悬架如何的工作,他们已经逐渐发展起来,这些年来,那里的悬架设计在未来的发展方向。
1.车辆动力学如果道路是完全平坦,没有违规行为,就没有必要停牌。
但远离道路平坦,即使是刚铺好的公路有细微的缺陷,与汽车的车轮相联系的。
它的这些缺陷聚焦于车轮。
根据牛顿运动定律,所有部队都大小和方向。
一个在路上碰到导致车轮向上和向下移动到垂直路面。
当然大小,取决于是否是惊人的一个巨大的车轮碰撞或一点点。
无论哪种方式,车轮垂直加速度的经验,因为它传递了一个缺陷。
如果没有中间结构,所有车轮的垂直能量转移到车架,这在同一方向移动。
在这种情况下,车轮与路面可以完全失去联系。
接着,在向下的重力,车轮可以大满贯回路面。
你需要的是一个系统,将吸收的能量垂直加速轮,使画面和身体不受干扰,而车轮按照道路颠簸。
对在工作力量上开动的汽车上被称为车辆动力学研究,你需要了解其中一些概念,以明白为什么暂停把必要摆在首位。
大多数汽车工程师从两个角度考虑的一个移动的汽车的动态:1)乘坐—汽车的能力,理顺了不平坦的道路2)处理—汽车的能力,安全地加速,刹车和角落这两个特点可以进一步说明在三个重要的原则—道路隔离,道路控股和转弯。
下表描述了这些原则和工程师如何尝试解决每一个独特的挑战。
汽车的悬挂其各个组成部分,提供了解决方案,所有描述。
2.底盘系统一辆汽车的悬挂,其实就是在底盘,其中包括对汽车底下找到了所有重要系统的一部分。
汽车车辆专业前桥外文文献翻译中英文翻译外文翻译
外文文献(一)外文原文Front axle general is in the front of the bus, also known as steering axle or drive bridge. Automobile front axle is the last important assemblies, including the steering knuckle kingpin, steering, front beam and other components. Front axle through the suspension and frame, used to support the ground and the frame between the vertical load, but also bear the braking force and lateral force and the force of torque, and ensure that the steering rotation right movement. The axle is connected with the frame through the suspension, support most of the weight of vehicle, and wheel traction or braking force, as well as the lateral force after suspension to frame. In the car used in the steering bridge, the stress condition is more complex, so it should have enough strength. In order to ensure the wheel turns to the correct positioning of angle, make manipulation of light and reduce tire wear, steering bridge should have enough stiffness. In addition, should also try to reduce the weight of the bridge. In short, because of the automobile in the running process of the front axle, the abominable working environment, complicated working condition, the load is alternating load, thus the parts easy to fatigue cracking and even rupture phenomenon. This requires that the structural design must have enough strength, stiffness and resistance to fatigue failure of the ability.The front axle is the main load-bearing parts: the front axle, my company has a tubular and forging type two structural forms, but mainly to forging type mainly. The front ends of each with a fist shape bold part as the kingpin of the site installation. In both sides of the spring support for partial surface, used for the installation of steel plate spring and accessories. Need note here is: U type bolt passes through the front mounting holes need matter beneath the back nut in, often can appear with the front axle sleeve back band interference problem. Why can appear such problem? Design is a problem, because the front dorsal ribs affects front axle load, therefore must have a certain size requirements, and if both before and after the U bolt distance design is too small, not enough gap assembly will appear above problem. Two technical problems, technical problems in two cases. The first is the front dorsal rib symmetry is not good or mounting hole symmetrical degree andeasy to cause the problem; the second is that some host plant in order to avoid the vulnerable, without taking into account the reality of the product and blind to the sleeve outer diameter. Kingpin: is the impact of vehicle performance of main parts. Kingpin has stop groove, pin lock bolt through the stop groove masterPin fixed on the front axle kingpin bore, so that it can't move can not move axially. Knuckle pin machining accuracy is very high, my company is one of the parts of key control. Steering knuckle: steering knuckle is the main steering part of front axle. It uses the main pin and the front axle is hinged by a pair of axle bearing supporting hub combination, to achieve the function of turning. Brake assembly: is the realization of the wheel brake main component, a brake oil and gas brake two forms. Implemented in the vehicle brake command, brake friction plate through the expansion and brake drum machining surface contact friction realization of vehicle brake. Front axle brake option is very critical, if the choice is undeserved, can appear before and after the brake force is not a match, the braking force is not up to the requirements of many problems. Hub combination : by two rolling bearings mounted on the steering knuckle, drive the rotation of the wheels. At the same time with the friction plate to form a friction pair, to realize the brake wheel. Arm: straight rod arm, tie rod arm, respectively, and a straight rod assembly and the tie rod assembly. Formed a steering mechanism and a steering trapezoidal mechanism. The steering mechanism to complete the vehicle steering, steering trapezoid determines the vehicle inside and outside corner is reasonable. The tie rod assembly: is to adjust the beam before the main parts. The rod body is made of seamless steel tube manufacturing, both ends of the spherical hinge joint structure is the joint assembly, by a thread after the installation of the tie rod arm, the rod body is adjustable, so as to adjust the toe. Front axle under the front of the car weight, the car forward thrust from the frame to the wheel, and with the steering device arranged on parts make joint type connection, the implementation of the automobile steering. The front axle is the use of both ends of it through the main pin and the steering knuckle is connected to the steering knuckle, swing to realize vehicle direction.In order to make the running vehicle has good linear driving ability, front axle should meet the following requirements: in order to make the running vehicle has good linear driving ability, front axle should meet the following requirements:1sufficient strength,in order to ensure the reliable bearing wheel and frame ( or monocoque ) between the work force. 2 correct positioning of the wheels, so that the steering wheel movement stability, convenient operation and reduce tire wear. Front wheel positioning includes kingpin inclination, caster, camber and toe-in. 3sufficient rigidity, the force deformation small, ensure the main pin and a steering wheel positioned right angle remains constant. 4knuckle and master pin, steering and front axle between the friction should be as small as possible, to ensure that the steering operation for portability, and has sufficient abrasion resistance. 5 steering wheel shimmy should be as small as possible, in order to ensure the vehicle normal, stable exercise. 6 front axle quality should be as small as possible, in order to reduce unsprung mass, improve vehicle ride comfort.1mini car front axle 1mini car front mini car front suspension generally adopt the independent suspension structure. Front axle load is relatively small, the structure is simple. Mini car front axle usually disconnected movable joint structure, which is composed of a front axle body, strengthen the transverse swing arm, arm etc.. 2 car front axle2 car front axle front axle suspension with Mcpherson car. It bears the driving and steering functions, the suspension is connected with the vehicle body, and the lower end of the wheel bearing housing connected, wheel camber is through the suspension and the bearing shell of the connecting bolt to adjust, auxiliary frame through the elastic part by controlling the arm, ball hinge connected with suspension, improve the driving stability and ride comfort. 3off-road vehicle front axle3off-road vehicle front axle Off-road vehicle steering and driving front axle has two tasks, it is known as the steering driving axle. And it generally drive the movable bridge, with a main driver, differential and the axle shaft. The difference is, due to the need, half shaft is divided into two segments, and by a universal joint, while the main pin are made under paragraph two. The 4truck front axle 4truck front axle truck front axle with I-shaped cross section is mainly used to improve the front bending strength. The upper two plus wide plane, to support the steel plate spring. The front ends each having a fist shape portion, which has a through hole, as a kingpin only. Main pin and left steering knuckle hinge, with a threaded wedge pin crossed with the main pin hole of vertical through holes on the lock pin wedge surface, the main pin is fixed in the axle hole, so that it cannot rotate.In general, common material needed to define the material properties including: elastic modulus, Poisson's ratio, density, specific heat, thermal expansion coefficient. The front axle is mainly composed of two parts, material composition, i.e., front axle and steering knuckle such as zero Department of materials. The front axle is adopted as the material of45 steel, steering knuckle materials using 40Cr.Torsion bar of automobile front independent suspension is the key component, is a slender rod, the induction quenching process is the manufacturing process difficult point, this paper introduces the torsion bar quenching inductor and its process test results, determined using half ring type inductor continuous quenching technology, this method can meet the technical requirements and the quantities of torsion bar production.The forging forging molding, not only greater deformation, but also requires a certain deformation force,Therefore the selection of J53series double disc friction press comparative economics, this series press combined slipping flywheel, combined slipping flywheel can provide highly deformed large forgings with enough to form, and can provide for forgings will required deformation capacity, and not to overload, the series press equipment investment, the cost of the mold and forging cost than die forging hammer and the forging crank press cheap cheap host. At present, the domestic automobile front axle machining process are the following: (1) of two plane milling plate spring seat; the drill two spring seat plane ten holes; the rough milling of two main pin hole of upper and lower end surfaces; the fine mill main pin hole of upper and lower end surfaces; the drilling and reaming main pin hole; the broaching the main pin hole; the main pin hole on the lower end of the countersink reaming pin holes;. In this scheme, the following questionQuestions:1 adopting main pin hole positioning countersink on the lower end, and the end surface of the main pin hole verticality can not be guaranteed, the main pin hole size height can not be guaranteed to the main pin hole; the positioning of the drill pin hole, drill through the cross intersection holes, easy cutting phenomenon, students offset, causing the main pin hole and the locking pin hole center distance can not be guaranteed. (2) of two plane milling plate spring seat; the drill two spring seat plane ten holes; the drilling and reaming pin holes on the rough milling of a main pin hole on upper end; the fine mill main pin hole of upperand lower end surfaces; the drilling and reaming main pin hole. In this scheme, there are the following problems: the process is used to drill the locking pin hole after the drill main pin hole, and the pin - fL: fL size and position size is the key size, kingpin is difficult to ensure the accuracy of the first; fine mill main pin hole of the upper and lower ends after processing the main pin hole, end relative to the main pin hole verticality is difficult to guarantee. (3) of two plane milling plate spring seat; the drill two spring seat plane ten holes; the drilling and reaming pin holes; the rough milling kingpin on upper end; the drilling and reaming main pin hole; the fine mill main pin hole on the lower end surface. In this scheme, there are the following problems : the main pin hole and the pin hole cross intersecting hole size tolerance of0.1mm is not easy to maintain; to adopt the reaming main pin hole, the dimensional tolerances are not easy to be ensured; the final finish milling main pin hole on the lower end surface. The main pin hole and upper and lower end verticality is not easy to guarantee; the main pin hole size can not be guaranteed.Along with our country transportation enterprise rapid development, auto transport carrying capacity and running speed are continually increasing with. So people to the safe operation of the automobile is more and more attention, so the automobile axle design also raised taller requirement. As a result of foreign automobile development starts early, technical inputs, thus technically far ahead of China market, but also there are many insufficient places, still need to improve, technology also needs a breakthrough. Steam car industry as our focus on the development of pillar industries, its prospect is very wide. At present, auto parts production has certain potential, but most enterprises in product research, development and other aspects of the defect, especially lack of less product independent development capacity, can not adapt to the system support, delivery of modules, to participate in international division of labor. Because of this, in the future development, Chinese enterprises should actively absorb the international advanced automotive technology, and constantly improve the self body lines, such as braking systems, steering systems, expand the industry of product variety, improve the integral technology level, increase the strong technological development capability, urges the enterprise faster development, adapt to the trend of globalization of automobile industry.100 years ago, the car was just beginning, the steering is modelled on the carriageand bicycle steering mode, using a joystick or a handle to make the front wheel deflection, thus realizes the steering. Due to the manipulation of effort and unreliable, so often fatal accident. The first horseless pull four wheel vehicle comes out, have a front axle and a front wheel assembly, the assembly being mounted on the crankshaft, front axle center around a point of rotation, using a rod connecting the front axle, focus, through the floor and extends upward, the wheel is fastened on the rod end, in order to manipulate the car. This device in a vehicle speed not exceeding the speed, or very good, but when the vehicle speed is increased, the driver asks to improve steering accuracy, in order to reduce tire wear, prolong the service life of tyre. In 1817, the Germans Lincoln Spang Jay presented similar to the modern automobile, the front wheel with knuckle and beam connection, he developed a kind of automobile front wheel on the main shaft to allow independent rotary structure, which is connected with the steering wheel, steering knuckle and a rotatable pin and front axle, thereby the invention of modern steering trapezoidal mechanism.Since China's reform and opening up, execute in the country the household contract responsibility system reform, make the rural economy is all-time and active. Rural freight traffic and population flow increased dramatically, speeding up the transportation mechanization into rural classicsEconomic development urgent need, it is also the needs of the market that has Chinese distinguishing feature of transport machinery -- emerge as the times require small truck. It has solved the countryside transportation need, fill the villages, townships, towns and urban transportation network is blank, active rural economics, for the surplus rural labor force to find a way out, so that tens of thousands of farmers to be on comparatively well-off road.Small truck manufacturing process is simple, cheap, purchase a car farmers generally in a year or so we can recover the cost. In addition, the highway construction has promoted the rapid development of small truck, the98% villages are on the road, so that the small truck with play.We want to develop a small truck to optimize the design, to make new products, diversification of varieties to meet a variety of needs. In a small truck design, how the complex road conditions to ensure the smooth running of the car quickly, is a serious problem. Then there is the subject of research and design.Automobile front axle driving system important constituent, it is connected with the frame through the suspension, steering wheel mounted at both ends, used to support frame and transmission wheel and frame between a variety of force, and drives the steering knuckle swing to realize vehicle steering. Using the hinge device causes the wheel to deflect a certain angle, so as to realize the steering of a vehicle axle called steering bridge, general vehicle used for steering bridge bridge, the front for steering bridge. Steering bridge not only can make the left and right wheels arranged at the front end to deflect a certain angle to realize the steering, should also be able to bear vertical load and by the road, the brake force is exerted on the longitudinal force and lateral force and the force formed by the moment. Therefore, the steering bridge must have sufficient strength and rigidity. Wheel steering process of internal friction between the pieces should be as small as possible, and to keep the vehicle steering light and the direction stability.Steering axle is generally composed of front axle, steering knuckle, steering knuckle arm, steering knuckle pin and the hub.Front axle general is in the front of the bus, also known as steering axle or drive bridge. The suspension is connected with the frame, used to support the ground and the frame between the vertical load, but also bear the braking force and lateral force and the force moment, and ensure that the steering rotation right movement. In the car used in the steering bridge, stress is more complex, so it should have enough strength. In order to ensure the correct positioning of the steering wheel angle, make the manipulation of light and reduce tire wear, steering bridge should have enough stiffness. In addition, should also try to reduce the weight of the bridge.Front axle under the front of the car weight, the car forward thrust from the frame to the wheel, and the steering device on parts make joint type connection, the implementation of the automobile steering. The cross-country vehicle front axle but also bear and rear axle the same driving task. General cargo vehicle with front engine rear drive arrangement, the front for steering bridge.Automobile front axle design should ensure adequate design strength, to ensure reliable bear acting force between wheel and frame; ensure the adequate rigidity, so that the wheel positioning parameters constant; ensure that the steering wheel have thecorrect localization angle, so that the steering wheel movement stability, convenient operation and reduce the tire friction; steering bridge quality as small as possible, in order to reduce non spring quality, improve the ride comfort of vehicles.译文前桥一般位于汽车的前部,也称转向桥或从动桥。
普通级轿车前悬架(麦弗逊式)设计毕业论文(含外文翻译)
摘要悬架是现代汽车上的重要总成之一,它把车架(或车身)与车轴(或轮胎)弹性地连接起来。
它的主要作用是传递作用在车轮和车身之间的一切力和力矩,比如支撑力、制动力和驱动力等,并且缓和由不平路面传给车身的冲击载荷、衰减由此引起的振动、保证乘员的舒适性、减小货物和车辆本身的动载荷。
本文完成的是东方之子轿车前悬架设计,重点从东方之子轿车前悬架的选型、减振器的计算及选型、弹性元件形式的选择计算及选型和横向稳定杆的设计计算。
首先,我把形式不同的悬架的优缺点进行了比较,然后定下东方之子轿车前悬架的形式—麦弗逊式悬架,最后围绕麦弗逊式悬架的部件进行设计。
先是弹簧的设计计算,再是减振器的计算选型,最后是横向稳定杆的设计。
关键词:悬架;麦弗逊式;设计AbstractSuspension is an important element of one of the modern automobile, it flexibly to link the chassis (orbody) and axle (or tires) . Its main role is the role of transmission in the bodybetween the wheels and all the power and moment, such as support of, system dynamics anddriving force, and easing the road to the whole body impact load, decay resulting vibration,ensure the comfort of the crew, cargo and vehicles reduce their moving load.The main stress is front suspension design,Training emphasis from the former car models,and models Absorber calculations, flexible choice of components and models and forms ofstabilizer bar design data.First of all, I have a different form of a suspension of the advantages and disadvantagescompared to the previous suspension of the car and then set form Eastar on suspension.Then design around Eastar suspension components. First, the spring-loaded design terms,to be absorber calculation models, a horizontal stabilizer bar final calculation. stabilizer bar.Keyword : Suspension, Macpherson ,Design目录摘要 (I)Abstract (II)1绪论 (1)1.1课题背景和意义 (1)1.2 悬架的发展历史和现状 (2)1.3 悬架的发展趋势 (4)1.4课题主要内容和研究目的 (5)2悬架结构方案分析 (6)2.1 悬架总成分析 (6)2.2独立悬架优缺点分析 (7)2.3独立悬架特点与分类 (8)2.3.1双横臂式悬架结构及特性分析 (8)2.3.2单横臂式悬架结构及特性分析 (9)2.3.3单纵臂式悬架结构及特性分析 (10)2.3.4单斜臂式悬架结构及特性分析 (11)2.3.5麦弗逊式悬架结构及特性分析 (12)2.1.6扭转梁式悬架结构及特性分析 (13)3麦弗逊式独立悬架设计 (14)3.1麦弗逊式独立悬架设计概述 (14)3.3麦弗逊悬架的结构分析 (15)3.4悬架的弹性特性设计 (16)3.5 悬架挠度fc 的设计 (17)3.5.1悬架静挠度 fc 的设计 (17)3.5.2悬架动挠度fd设计 (18)3.6悬架弹性元件设计 (18)3.6.1螺旋弹簧分析 (18)3.6.2螺旋弹簧的材料及许用应力选择 (19)3.6.3 弹簧参数的计算选择 (20)3.6.4计算空载刚度 (20)3.6.5计算满载刚度 (20)3.6.6按满载计算弹簧钢丝直径 (21)3.6.7螺旋弹簧校核 (21)3.6.8小结 (22)3.7导向机构设计 (23)3.7.1导向机构的设计要求 (23)3.7.2导向机构的布置参数 (24)3.7.3导向机构的受力分析 (27)3.7.4横臂轴线布置方式的选择 (27)3.7.5横摆臂参数对车轮定位参数的影响 (28)3.7.6 导向机构建模 (29)3.8 减振器的设计 (30)3.8.1减振器的简单分类 (30)3.8.2双向筒式液力减振器工作原理 (30)3.8.3相对阻力系数ψ (31)3.8.4减振器阻尼系数δ的确定 (32)3.8.5减振器工作缸直径D的确定 (33)3.8.6小结 (33)3.9横向稳定器 (34)3.10 悬架结构元件 (35)4 前轮定位参数 (37)4.1主销后倾角 (37)4.2主销内倾角 (39)4.3 前轮外倾角 (40)4.4前轮前束 (41)5 麦弗逊悬架其他零件基于CATIA的建模 (43)5.1车轮的建模 (43)5.2车轮轴承建模 (44)5.3转向节建模 (44)5.4 减振器与转向节连接件建模 (45)5.5 车架和横向稳定器联合建模 (45)5.6 麦弗逊悬架建模装配图 (46)6 基于adams的悬架仿真分析 (47)6.1主销内倾角仿真分析 (47)6.2 主销后倾角分析 (47)6.3前轮外倾角分析 (48)6.4 车轮跳动量分析 (49)6.5 前轮前束分析 (49)6.6定位参数与车轮跳动量联合分析 (50)6.7小结 (51)结束语 (52)致谢.............................................................................................. 错误!未定义书签。
汽车悬架原理外文文献翻译中英文
汽车悬架原理外文文献翻译(含:英文原文及中文译文)文献出处:Journal of Biomechanics, 2013, 4(5):30-39.英文原文The rinciple of Car SuspensionsWilliam HarrisUniversity of MichiganWhen people think of automobile performance, they normally think of horsepower, torque and zero-to-60 acceleration. But all of the power generated by a piston engine is useless if the driver can't control the car. That's why automobile engineers turned their attention to the suspension system almost as soon as they had mastered the four-stroke internal combustion engine.The job of a car suspension is to maximize the friction between the tires and the road surface, to provide steering stability with good handling and to ensure the comfort of the passengers. In this article, we'll explore how car suspensions work, how they've evolved over the years and where the design of suspensions is headed in the future.1.Vehicle DynamicsIf a road were perfectly flat, with no irregularities, suspensions wouldn't be necessary. But roads are far from flat. Even freshly paved highways have subtle imperfections that can interact with the wheels of acar. It's these imperfections that apply forces to the wheels. According to Newton's laws of motion, all forces have both magnitude and direction. A bump in the road causes the wheel to move up and down perpendicular to the road surface. The magnitude, of course, depends on whether the wheel is striking a giant bump or a tiny speck. Either way, the car wheel experiences a vertical acceleration as it passes over an imperfection. Without an intervening structure, all of wheel's vertical energy is transferred to the frame, which moves in the same direction. In such a situation, the wheels can lose contact with the road completely. Then, under the downward force of gravity, the wheels can slam back into the road surface. What you need is a system that will absorb the energy of the vertically accelerated wheel, allowing the frame and body to ride undisturbed while the wheels follow bumps in the road.The study of the forces at work on a moving car is called vehicle dynamics, and you need to understand some of these concepts in order to appreciate why a suspension is necessary in the first place. Most automobile engineers consider the dynamics of a moving car from two perspectives:1)Ride - a car's ability to smooth out a bumpy road2)Handling - a car's ability to safely accelerate, brake and cornerThese two characteristics can be further described in three important principles - road isolation, road holding and cornering. The table belowdescribes these principles and how engineers attempt to solve the challenges unique to each.A car's suspension, with its various components, provides all of the solutions described.2.The Chassis SystemThe suspension of a car is actually part of the chassis, which comprises all of the important systems located beneath the car's body.These systems include:1) T he frame - structural, load-carrying component that supports the car's engine and body, which are in turn supported by the suspension2) T he suspension system - setup that supports weight, absorbs and dampens shock and helps maintain tire contact3) T he steering system - mechanism that enables the driver to guide and direct the vehicle4) T he tires and wheels - components that make vehicle motion possible by way of grip and/or friction with the roadSo the suspension is just one of the major systems in any vehicle.With this big-picture overview in mind, it's time to look at the three fundamental components of any suspension: springs, dampers and anti-sway bars.3.SpringsToday's springing systems are based on one of four basic designs:1) Coil springs - This is the most common type of spring and is, in essence, a heavy-duty torsion bar coiled around an axis. Coil springs compress and expand to absorb the motion of the wheels.2) Leaf springs - This type of spring consists of several layers of metal (called "leaves") bound together to act as a single unit. Leaf springs were first used on horse-drawn carriages and were found on most American automobiles until 1985. They are still used today on most trucks and heavy-duty vehicles.3) Torsion bars - Torsion bars use the twisting properties of a steel bar to provide coil-spring-like performance. This is how they work: One end of a bar is anchored to the vehicle frame. The other end is attached to a wishbone, which acts like a lever that moves perpendicular to the torsion bar. When the wheel hits a bump, vertical motion is transferred to the wishbone and then, through the levering action, to the torsion bar. Thetorsion bar then twists along its axis to provide the spring force. European carmakers used this system extensively, as did Packard and Chrysler in the United States, through the 1950s and 1960s. 4) Air springs - Air springs, which consist of a cylindrical chamber of air positioned between the wheel and the car's body, use the compressive qualities of air to absorb wheel vibrations. The concept is actually more than a century old and could be found on horse-drawn buggies. Air springs from this era were made from air-filled, leather diaphragms, much like a bellows; they were replaced with molded-rubber air springs in the 1930s.Based on where springs are located on a car -- i.e., between the wheels and the frame -- engineers often find it convenient to talk about the sprung mass and the unsprung mass.4.Sprung and Unsprung MassThe sprung mass is the mass of the vehicle supported on the springs, while the unsprung mass is loosely defined as the mass between the road and the suspension springs. The stiffness of the springs affects how the sprung mass responds while the car is being driven. Loosely sprung cars, such as luxury cars (think Lincoln Town Car), can swallow bumps and provide a super-smooth ride; however, such a car is prone to dive and squat during braking and acceleration and tends to experience body sway or roll during cornering. Tightly sprung cars, such as sports cars (think Mazda Miata), are less forgiving on bumpy roads, but they minimizebody motion well, which means they can be driven aggressively, even around corners.So, while springs by themselves seem like simple devices, designing and implementing them on a car to balance passenger comfort with handling is a complex task. And to make matters more complex, springs alone can't provide a perfectly smooth ride. Why? Because springs are great at absorbing energy, but not so good at dissipating it. Other structures, known as dampers, are required to do this.5.Shock AbsorbersUnless a dampening structure is present, a car spring will extend and release the energy it absorbs from a bump at an uncontrolled rate. The spring will continue to bounce at its natural frequency until all of theenergy originally put into it is used up. A suspensionbuilt on springs alone would make for an extremely bouncy ride and, depending on the terrain, an uncontrollable car.Enter the shock absorber, or snubber, a device that controls unwanted spring motion through a process known as dampening. Shock absorbers slow down and reduce the magnitude of vibratory motions by turning the kinetic energy of suspension movement into heat energy that can be dissipated through hydraulic fluid. To understand how this works, it's best to look inside a shock absorber to see its structure and function.A shock absorber is basically an oil pump placed between the frame of the car and the wheels. The upper mount of the shock connects to the frame (i.e., the sprung weight), while the lower mount connects to the axle, near the wheel (i.e., the unsprung weight). In a twin-tube design, one of the most common types of shock absorbers, the upper mount is connected to a piston rod, which in turn is connected to a piston, which in turn sits in a tube filled with hydraulic fluid. The inner tube is known as the pressure tube, and the outer tube is known as the reserve tube. The reserve tube stores excess hydraulic fluid.When the car wheel encounters a bump in the road and causes the spring to coil and uncoil, the energy of the spring is transferred to the shock absorber through the upper mount, down through the piston rod and into the piston. Orifices perforate the piston and allow fluid to leakthrough as the piston moves up and down in the pressure tube. Because the orifices are relatively tiny, only a small amount of fluid, under great pressure, passes through. This slows down the piston, which in turn slows down the spring.Shock absorbers work in two cycles -- the compression cycle and the extension cycle. The compression cycle occurs as the piston moves downward, compressing the hydraulic fluid in the chamber below the piston. The extension cycle occurs as the piston moves toward the top of the pressure tube, compressing the fluid in the chamber above the piston.A typical car or light truck will have more resistance during its extension cycle than its compression cycle. With that in mind, the compression cycle controls the motion of the vehicle's unsprung weight, while extension controls the heavier, sprung weight.All modern shock absorbers are velocity-sensitive -- the faster the suspension moves, the more resistance the shock absorber provides. This enables shocks to adjust to road conditions and to control all of the unwanted motions that can occur in a moving vehicle, including bounce, sway, brake dive and acceleration squat.6.Struts and Anti-sway BarsAnother common dampening structure is the strut -- basically a shock absorber mounted inside a coil spring. Struts perform two jobs: They provide a dampening function like shock absorbers, and they provide structural support for the vehicle suspension. That means struts deliver a bit more than shock absorbers, which don't support vehicle weight -- they only control the speed at which weight is transferred in a car, not the weight itself.Because shocks and struts have so much to do with the handling of a car, they can be considered critical safety features. Worn shocks and struts can allow excessive vehicle-weight transfer from side to side and front to back. This reduces the tire's ability to grip the road, as well as handling and braking performance.7.Anti-sway BarsAnti-sway bars (also known as anti-roll bars) are used along with shock absorbers or struts to give a moving automobile additional stability. An anti-sway bar is a metal rod that spans the entire axle and effectively joins each side of the suspension together.When the suspension at one wheel moves up and down, the anti-sway bar transfers movement to the other wheel. This creates a more level ride and reduces vehicle sway. In particular, it combats the roll of a car on its suspension as it corners. For this reason, almost all cars today are fitted with anti-sway bars as standard equipment, although if they're not, kits make it easy to install the bars at any time.8.The Future of Car SuspensionsWhile there have been enhancements and improvements to both springs and shock absorbers, the basic design of car suspensions has not undergone a significant evolution over the years. But all of that's about to change with the introduction of a brand-new suspension design conceived by Bose -- the same Bose known for its innovations in acoustic technologies. Some experts are going so far as to say that the Bose suspension is the biggest advance in automobile suspensions since the introduction of an all-independent design.How does it work? The Bose system uses a linear electromagnetic motor (LEM) at each wheel in lieu of a conventional shock-and-spring setup. Amplifiers provide electricity to the motors in such a way that theirpower is regenerated with each compression of the system. The main benefit of the motors is that they are not limited by the inertia inherent in conventional fluid-based dampers. As a result, an LEM can extend and compress at a much greater speed, virtually eliminating all vibrations in the passenger cabin. The wheel's motion can be so finely controlled that the body of the car remains level regardless of what's happening at the wheel. The LEM can also counteract the body motion of the car while accelerating, braking and cornering, giving the driver a greater sense of control.Unfortunately, this paradigm-shifting suspension won't be available until 2009, when it will be offered on one or more high-end luxury cars. Until then, drivers will have to rely on the tried-and-true suspension methods that have smoothed out bumpy rides for centuries.中文译文汽车悬架原理研究作者:威廉·哈里斯密歇根大学当人们想到汽车性能时,他们通常会联想到马力,扭矩和零到60码加速度。
中英文文献翻译—悬架与转向系统悬架与转向系统的基本组成与类型
中英文文献翻译—悬架与转向系统悬架与转向系统的基本组成与类型附录附录ABasic Parts and Types of the Suspension and Steering Systems Suspension SystemIf a vehicle's axles were bolted directly to its frame or body, every rough spot in the road would transmit a jarring force throughout the vehicle. Riding would be uncomfortable, and handling at freeway speeds would be impossible. The fact that the modern vehicle rides and handles well is a direct result of a suspension system.Even though the tires and wheels must follow the road contour, the body should be influenced as little as possible [1]. The purpose of any suspension system is to allow the body of the vehicle to travel forward with a minimum amount of up-and-down movement. The suspension should also permit the vehicle to make turns without excessive body roll or tire skidding.Suspension System ComponentsVehicle FrameA vehicle's frame or body must form a rigid structural foundation and provide solid anchorage points for the suspension system. There are two types of vehicle construction in common use today: body-over-frame construction, which uses a separate steel frame to which the body is bolted at various points and unibody construction, in which the body sections serve as structural members. Unibody construction is the most common, but body-over-frame construction is still used on pickup trucks and large cars.SpringsThe springs are the most obvious part of the suspension system. Every vehicle has a spring of some kind between the frame or body and the axles. There are three types of springs in general use today: leaf spring, coil spring, and torsion bar. Two different types of springs can be used on one vehicle. Air springs were once used in place of the other types of springs, but are now obsolete. Many modern vehicles have air-operated suspensions, but they are used to supplement the springs.Shock AbsorbersWhen the vehicle is traveling forward on a level surface and the wheels strike a bump, the spring is rapidly compressed (coil springs) or twisted (leaf springsand torsion bars). The spring will attempt to return to its normal loaded length. In so doing, it will rebound, causing the body of the vehicle to be lifted. Since the spring has stored energy, it will rebound past its normal length. The upward movement of the vehicle also assists in rebounding past the spring's normal length.The weight of the vehicle then pushes the spring down after the spring rebounds. The weight of the vehicle will push the spring down, but since the vehicle is traveling downward, the energy built up by the descending body will push the spring below its normal loaded height. This causes the spring to rebound again. This process, called spring oscillation, gradually diminishes until the vehicle is finally still. Spring oscillation can affect handling and ride quality and must be controlled.Air Shock AbsorbersSome suspension systems incorporate two adjustable air shock absorbers that are attached to the rear suspension andconnected to an air valve with flexible tubing.Air operated shock absorbers have hydraulic dampening systems which operate in the same manner as those on conventional shocks. In addition, they contain a sealed air chamber, which is acted on by pressure from a height control sensor. Varying the pressure to the air chamber causes the air shock to increase or decrease its length or operating range.Air pressure is delivered to the air shocks through plastic tubing. The tubing connects the shocks to an air valve. Air pressure for raising the shocks is generally obtained from an outside source, such as a service station compressor, and is admitted through the air valve. To deplete the shocks of unwanted air (lower vehicle curb height), the air valve core is depressed, allowing air to escape.Control ArmsAll vehicles have either control arms or struts to keep the wheel assembly in the proper position. The control arms and struts allow the wheel to move up and down while preventing it from moving in any other direction. The wheel will tend to move in undesirable directions whenever the vehicle is accelerated, braked, or turned. Vehicle suspensions may have control arms only or a combination of control arms and struts.Types of the SuspensionFront Suspension SystemsAlmost all modern front suspension systems are independent. With anindependent suspension, each front wheel is free to move up and down with a minimum effect on the other wheel. In an independent suspension system, there is also far less twisting motion imposed on the frame than in a system with a solid axle.Nevertheless, a few off-road, four wheel drive vehicles and large trucks continue to use a solid axle front suspension. The two major types of independent front suspension are the conventional front suspension and the MacPherson strut front suspension.Conventional Front Suspension In the conventional front suspension system, one or two control arms are used at each wheel. In most systems, the coil springs are mounted between the vehicle's frame and the lower control arm. In older systems, coil springs are mounted between the upper control arm and vehicle body. In a torsion bar front suspension system, the lower arm moves upward, it twists the torsion bar.Coil Spring Front Suspension Fig.11-1 shows a typical independent front suspension that uses rubber bushing control arm pivots. The top of the coil spring rests in a cup-like spot against the frame (unshown). The bottom of the coil spring is supported by a pad on the lower control arm. The top of each shock absorber is fastened to the frame; the bottom is attached to the lower control arm.Torsion Bar Front Suspension A torsion bar is located on each side of the frame in the front of the vehicle. The lower control arm is attached to the free end of the torsion bar. When the wheel is driven upward, the lower control arm moves upward, twisting the long spring steel bar.Macpherson Strut Front Suspension Most modern vehicles, especially those with front-wheel drive, use the MacPherson strut front suspension systems, Fig.11-2. Note that the MacPherson strut contains a coil spring, which is mounted on top of the heavy strut-and-pedestal assembly. The entire MacPherson strut assembly is attached to the steering knuckle at the lower part ofthe pedestal. The bottom of the MacPherson strut assembly is attached to the single control arm through a ball joint.The entire strut assembly turns when the wheel is turned. A bearing or thrust plate at the top of the strut assembly allows relative movement between the assembly and the vehicle body. The ball joint allows the strut assembly to turn in relation to the control arm. The strut contains a damper, which operates in the same manner as a conventional shock absorber. Most damper assemblies have a protective cover that keeps dirt and water away from the damper piston rod.The advantage of the MacPherson strut is its compact design, which allows more room for service on small car bodies.Solid Axle Front Suspension The use of the solid axle front suspension (or dependent suspension) is generally confined to trucks and off-road vehicles. This system uses a solid steel dead.Rear Suspension SystemsRear suspensions on vehicles with a solid rear axle housing generally utilize coil springs or leaf springs. When the vehicle has an independent rear suspension system, coil springs, MacPherson struts, a single transverse leaf spring, or even torsion bars can be used.Steering SystemThe steering system is designed to allow the driver to move the front wheels to the right or left with a minimum of effort and without excessive movement of the steering wheel. Although the driver can move the wheels easily, road shocks are not transmitted to the driver. This absence of road shock transfer is referred to as the nonreversible feature of steering systems.The basic steering system can be divided into three main assemblies:The spindle and steering arm assemblies.The linkage assembly connecting the steering arms and steering gear.The steering wheel, steering shaft, and steering gear assembly.Steering GearThe steering gear is designed to multiply the driver's turning torque so the front wheels may be turned easily. When the parallelogram linkage is used, the torque developed by the driver is multiplied through gears and is then transmitted to the wheel spindle assemblies through the linkage. On the rack-and-pinion steering system, the steering shaft is connected directly to the pinion shaft. Turning the pinion moves the rack section, witch moves the linkage. Late-model vehicles use either manual steering gears or power steering gears.There are three types of the steering gears in use: recirculating ball steering gear, worm-and-roller steering gear and rack-and-pinion steering gear.Power SteeringPower steering is designed to reduce the effort needed to turn the steering wheel by utilizing hydraulic pressure to bolster (strengthen) the normal torque developed bythe steering gear. Power steering systems should ease steering wheel manipulation and, at the same time, offer enough resistance so that the driver can retain some road feel. Power steering is used with both conventional and rack-and-pinion systems (Fig.11-3).The self-contained steering gear contains the control valve mechanism, the power piston, and the gears. Pressure developed by the unit is applied to the pitman shaftThe power rack-and-pinion steering system also uses a rotary control valve that directs the hydraulic fluid from the pump to either side of the rack piston. An overall view of this setup is shown in Figure 11-3. Steering wheel motion is transferred to the pinion. From there, it is sent through the pinion teeth, which are in mesh with the rack teeth. The integral rack piston, which is connected to the rack, changes hydraulic pressure to a linear force (back and forth movement in a straight line). This, in turn, moves the rack in a right or left direction. The force is transmitted by the inner and outer tie rods to the steering knuckles, which, in turn, move the wheels.附录B悬架与转向系统悬架与转向系统的基本组成与类型1.悬架系统如果将一辆汽车的车桥直接固定到车架或车身上,道路上的每个凹凸不平的点都会将一个冲击力传递给车辆。
双横臂式悬挂系统外文文献翻译、中英文翻译、外文翻译
附录双横臂式悬挂系统附录1 外文中文翻译按横臂数量的多少又分为双横臂式和单横臂式悬挂系统。
单横臂式具有结构简单,侧倾中心高,有较强的抗侧倾能力的优点。
但随着现代汽车速度的提高,侧倾中心过高会引起车轮跳动时轮距变化大,轮胎磨损加剧,而且在急转弯时左右车轮垂直力转移过大,导致后轮外倾增大,减少了后轮侧偏刚度,从而产生高速甩尾的严重工况。
单横臂式独立悬挂系统多应用在后悬挂系统上,但由于不能适应高速行驶的要求,目前应用不多。
双横臂式独立悬挂系统按上下横臂是否等长,又分为等长双横臂式和不等长双横臂式两种悬挂系统。
等长双横臂式悬挂系统在车轮上下跳动时,能保持主销倾角不变,但轮距变化大(与单横臂式相类似),造成轮胎磨损严重,现已很少用。
对于不等长双横臂式悬挂系统,只要适当选择、优化上下横臂的长度,并通过合理的布置、就可以使轮距及前轮定位参数变化均在可接受的限定范围内,保证汽车具有良好的行驶稳定性。
目前不等长双横臂式悬挂系统已广泛应用在轿车的前后悬挂系统上,部分运动型轿车及赛车的后轮也采用这一悬挂系统结构。
双横臂式独立悬架,是一种车轮在汽车横向平面内摆动的独立悬架,这种独立悬架被广泛应用在轿车前轮上。
双横臂,顾名思义,两条臂横向布置,两臂有做成A字形或V字形,V形臂的上下2个V形摆臂以一定的距离,分别安装在车轮上,另一端安装在车架上。
双横臂式独立悬架一般多为不等臂双横臂式,上臂比下臂短,当汽车车轮上下运动时,上臂比下臂运动弧度小。
这将使轮胎上部轻微地内外移动,而底部影响很小。
这种结构有利于减少轮胎磨损,提高汽车行驶平顺性和方向稳定性。
由于当双横臂式独立悬架悬架变形时,车轮平面将产生倾斜而改变两侧车轮与路面接触点的距离——轮距,致使轮胎相对于地面侧向滑移,破坏轮胎和地面的附着。
-1-附录2 外文文献Number by the number of arm is divided into wishbone and single -wishbone suspension system. Single-Arm has a simple structure, roll center height, there is a strong anti-roll capability advantages. But with the increased speed of modern cars, the roll center is too high will cause the wheel beats track changes, tire wear increased, and in sharp turns around the wheel vertical force when the transfer is too large, resulting in rear wheel camber increases, reducing the rear wheel cornering stiffness, resulting in a serious condition high-speed flick. Single-wishbone independent suspension system multi-application system in the rear suspension, but can not meet the requirements of high speed, the current application is small. Double wishbone independent suspension system is at the upper and lower arm of equal length, is divided into equal length wishbone and the unequal length double wishbone suspension system of two. Equal length double wishbone suspension system in the wheel up and down when the kingpin inclination to maintain the same, but the track changes in a large (and similar single-Arm), resulting in severe tire wear, is now rarely used. For the unequal length double wishbone suspension system, as long as the appropriate choice to optimize the length of the upper and lower arm, and by a reasonable arrangement to enable track and the front wheel alignment parameters are within acceptable limits to ensure the car have good driving stability. Present unequal length double wishbone suspension system has been widely used in cars, front and rear suspension systems, part of the sports car and the car's rear suspension system is also using this structure.Double wishbone independent suspension, is a horizontal plane in the automotive wheel independent suspension swing, which is widely used independent suspension on the front of the car. Double wishbone, by definition, two-arm horizontal arrangement, the arms are made of A-shaped or V-shaped, V-shaped upper and lower arm of the V-shaped arm 2 to a certain distance, the wheels were installed in the other end installed in the car rack.Double wishbone independent suspension in general are mostly ranging-2-arm double wishbone type, upper arm shorter than the lower arm, the wheel when the car moves up and down, the upper arm under the arm movement than the smaller arc. This will move the tire inside and outside the top slightly, while the bottom has little effect. This structure helps to reduce tire wear, improve vehicle ride comfort and directional stability. Because when the double wishbone independent suspension suspension deformation, tilt wheel plane will have to change the wheels on both sides of the distance between the point of contact with the road - tread, causing the tire slippage relative to the ground, damage the tire and the ground attachment.-3-。
汽车悬架系统中英文对照外文翻译文献
汽车悬架系统中英文对照外文翻译文献汽车悬架系统中英文对照外文翻译文献(文档含英文原文和中文翻译)汽车悬架现代汽车中的悬架系统有两种,一种是从动悬架,另一种是主动悬架。
从动悬架即传统式的悬架,是由弹簧、减振器(减振筒)、导向机构等组成,它的功能是减弱路面传给车身的冲击力,衰减由冲击力而引起的承载系统的振动。
其中弹簧主要起减缓冲击力的作用,减振器的主要作用是衰减振动。
由于这种悬架是由外力驱动而起作用的,所以称为从动悬架。
而主动悬架的控制环节中安装了能够产生抽动的装置,采用一种以力抑力的方式来抑制路面对车身的冲击力及车身的倾斜力。
由于这种悬架能够自行产生作用力,因此称为主动悬架。
主动悬架是近十几年发展起来的,由电脑控制的一种新型悬架,具备三个条件:(1)具有能够产生作用力的动力源;(2)执行元件能够传递这种作用力并能连续工作;(3)具有多种传感器并将有关数据集中到微电脑进行运算并决定控制方式。
因此,主动悬架汇集了力学和电子学的技术知识,是一种比较复杂的高技术装置。
例如装置了主动悬架的法国雪铁龙桑蒂雅,该车悬架系统的中枢是一个微电脑,悬架上有5 种传感器,分别向微电脑传送车速、前轮制动压力、踏动油门踏板的速度、车身垂直方向的振幅及频率、转向盘角度及转向速度等数据。
电脑不断接收这些数据并与预先设定的临界值进行比较,选择相应的悬架状态。
同时,微电脑独立控制每一只车轮上的执行元件,通过控制减振器内油压的变化产生抽动,从而能在任何时候、任何车轮上产生符合要求的悬架运动。
因此,桑蒂雅桥车备有多种驾驶模式选择,驾车者只要扳动位于副仪表板上的“正常”或“运动”按钮,轿车就会自动设置在最佳的悬架状态,以求最好的舒适性能。
另外,主动悬架具有控制车身运动的功能。
当汽车制动或拐弯时的惯性引起弹簧变形时,主动悬架会产生一个与惯力相对抗的力,减少车身位置的变化。
例如德国奔驰2000 款CL 型跑车,当车辆拐弯时悬架传感器会立即检测出车身的倾斜和横向加速度,电脑根据传感器的信息,与预先设定的临界值进行比较计算,立即确定在什么位置上将多大的负载加到悬架上,使车身的倾斜减到最小。
汽车车辆专业悬架外文文献翻译中英文翻译外文翻译
汽车车辆专业悬架外文文献翻译、中英文翻译、外文翻译外文文献(二)外文原文Abstract: To improve the suspension performance and steering stability of light vehicles, we built a kinematic simulation model of a whole independent double-wishbone suspension system by using ADAMS software, created random excitations of the test platforms of respectively the left and the right wheels according to actual running conditions of a vehicle, and explored the changing patterns of the kinematic characteristic parameters in the process of suspension motion. The irrationality of the suspension guiding mechanism design was pointed out through simulation and analysis, and the existent problems of the guiding mechanism were optimized and calculated. The results show that all the front-wheel alignment parameters, including the camber, the toe, the caster and the inclination, only slightly change within corresponding allowable ranges in design before and after optimization. The optimization reduces the variation of the wheel-center distance from 47.01 mm to a change of 8.28 mm within the allowable range of -10 mm to 10 mm, promising an improvement of the vehicle steering stability. The optimization also confines the front-wheel sideways slippage to a much smaller change of 2.23 mm; this helps to greatly reduce the wear of tires and assure the straight running stability of the vehicle. Keywords: vehicle suspension; vehicle steering; riding qualities; independent double-wishbone suspension; kinematic characteristic parameter; wheel-center distance; front-wheel sideways slippage1 IntroductionThe function of a suspension system in a vehicle is to transmit all forces and moments exerted on the wheels to the girder frame of the vehicle, smooth the impact passing from the road surface to the vehicle body and damp the impact-caused vibration of the load carrying system. There are many different structures of vehicle suspension, of which the independent double-wishbone suspension is most extensively used. An independent double-wishbone suspension system is usually a group of space RSSR (revolute joint - spherical joint -spherical joint - revolute joint) four-bar linkage mechanisms. Its kinematic relations are complicated, its kinematic visualization is poor, and performance analysis is very difficult. Thus, rational settings of theposition parameters of the guiding mechanism are crucial to assuring good performance of the independent double-wishbone suspension. The kinematiccharacteristics of suspension directly influence the service performance of the vehicle, especially steering stability, ride comfort, turning ease, and tire life.In this paper, we used ADAMS software to build a kinematic analysis model of an independent double-wishbone suspension, and used the model to calculate and optimize the kinematic characteristic parameters of the suspension mechanism. The optimization results are helpful for improving the kinematic performance of suspension.12 Modeling independent double-wishbone suspensionThe performance of a suspension system is reflected by the changes of wheel alignment parameters when the wheels jump. Those changes should be kept within rational ranges to assure the designed vehicle running performance. Considering the symmetry of the left and right wheels of a vehicle, it is appropriate to study only the left or the right half of the suspension system to understand the entire mechanism, excluding the variation of WCD (wheel center distance). We established a model of the left half of an independent double-wishbone suspension system as shown in Figure 1.3 Kinematic simulation analysis of suspension modelConsidering the maximum jump height of the front wheel, we positioned the drives on the translational joints between the ground and the test platform, and imposed random displacement excitations on the wheels to simulate the operating conditions of a vehicle running on an uneven road surface.The measured road-roughness data of the left and right wheels were converted into the relationship between time and road roughness at a certain vehicle speed. The spline function CUBSPL in ADAMS was used to fit and generate displacement-time history curves of excitation. The simulationresults of the suspension system before optimization are illustrated in Figure 2.The camber angle, the toe angle, the caster angle and the inclination angle change only slightly within the corresponding designed ranges with the wheel jumping distance. This indicates an under-steering behavior together with an automatic returnability, good steering stability and safety in arunning process. However, WCD decreases from 1 849.97 mm to 1 896.98 mm and FWSS from 16.48 mm to -6.99 mm, showing remarkable variations of 47.01 mm and 23.47 mm, respectively. Changes so large in WCD and FWSS are adverse to the steering ease and straight-running stability, and cause quick wear, thus reducing tire life.For independent suspensions, the variation of WCD causes side deflectionof tires and then impairs steering stability through the lateral force input. Especially when the right and the left rolling wheels deviate in the same direction, the WCD-caused lateral forces on the right and the left sidescannot be offset and thus make steering unstable. Therefore, WCD variation should be kept minimum, and is required in suspension design to be within the range from -10 mm to 10 mm when wheels jump. It is obvious that the WCD ofnon-optimized structure of the suspension system goes beyond this range. The structure needs modifying to suppress FWSS and the change of WCD with thewheel jumping distance. ADMAS software is a strong tool for parameter optimization and analysis. It creates a parameterization model by simulating with different values of model design variables, and then analyzes the parameterization based on the returned simulation results and the final optimization calculation of all parameters. During optimization, the program automatically adjusts design variables to obtain a minimum objective function [8-10]. To reduce tire wear and improve steering stability, the Table 1 Values of camber angle α , toe angle θ , caster angle γ and inclination angle β before and after optimization2Table 1 The data tables of optimize the results4 ConclusionsThe whole kinematic simulation model of an independent double-wishbone suspension system built by using ADAMS software with the left and the right suspension parts under random excitations can improve the calculationprecision by addressing the mutual impacts of kinematic characteristic parameters of the left and the right suspension parts under random excitations. The optimization can overcome the problem of the too large variation of WCDand overly large FWSS with the wheel jumping distance. The kinematic characteristic parameters of the suspension system reach an ideal range, demonstrating that the optimization protocol is feasible. From a practicalperspective, the optimization is expected to reduce tire wear, and remarkably improve suspension performance and vehicle steering stability.Figure 1 simple picture of suspensionFigure 2 Curve with the parameters of the suspension3译文摘要:为了提高轻型车辆性能和行驶稳定,我们使用ADAMS软件建立一个独立双横臂悬架系统运动仿真模型,并建立随机激励的测试平台,根据车辆实际运行条件,探讨悬架的运动学特征参数的变化。
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汽车悬架系统中英文对照外文翻译文献(文档含英文原文和中文翻译)汽车悬架现代汽车中的悬架系统有两种,一种是从动悬架,另一种是主动悬架。
从动悬架即传统式的悬架,是由弹簧、减振器(减振筒)、导向机构等组成,它的功能是减弱路面传给车身的冲击力,衰减由冲击力而引起的承载系统的振动。
其中弹簧主要起减缓冲击力的作用,减振器的主要作用是衰减振动。
由于这种悬架是由外力驱动而起作用的,所以称为从动悬架。
而主动悬架的控制环节中安装了能够产生抽动的装置,采用一种以力抑力的方式来抑制路面对车身的冲击力及车身的倾斜力。
由于这种悬架能够自行产生作用力,因此称为主动悬架。
主动悬架是近十几年发展起来的,由电脑控制的一种新型悬架,具备三个条件:(1)具有能够产生作用力的动力源;(2)执行元件能够传递这种作用力并能连续工作;(3)具有多种传感器并将有关数据集中到微电脑进行运算并决定控制方式。
因此,主动悬架汇集了力学和电子学的技术知识,是一种比较复杂的高技术装置。
例如装置了主动悬架的法国雪铁龙桑蒂雅,该车悬架系统的中枢是一个微电脑,悬架上有5 种传感器,分别向微电脑传送车速、前轮制动压力、踏动油门踏板的速度、车身垂直方向的振幅及频率、转向盘角度及转向速度等数据。
电脑不断接收这些数据并与预先设定的临界值进行比较,选择相应的悬架状态。
同时,微电脑独立控制每一只车轮上的执行元件,通过控制减振器内油压的变化产生抽动,从而能在任何时候、任何车轮上产生符合要求的悬架运动。
因此,桑蒂雅桥车备有多种驾驶模式选择,驾车者只要扳动位于副仪表板上的“正常”或“运动”按钮,轿车就会自动设置在最佳的悬架状态,以求最好的舒适性能。
另外,主动悬架具有控制车身运动的功能。
当汽车制动或拐弯时的惯性引起弹簧变形时,主动悬架会产生一个与惯力相对抗的力,减少车身位置的变化。
例如德国奔驰2000 款CL 型跑车,当车辆拐弯时悬架传感器会立即检测出车身的倾斜和横向加速度,电脑根据传感器的信息,与预先设定的临界值进行比较计算,立即确定在什么位置上将多大的负载加到悬架上,使车身的倾斜减到最小。
汽车主动悬架—液压和空气式从控制力的角度划分,悬架可分为被动悬架,半主动悬架和主动悬架。
目前,大多数汽车的悬架系统装有弹簧和减振器,悬架系统内无能源供给装置,其弹性和阻尼不能随外部工况变化,因此称这种悬架是被动悬架。
主动悬架有作为直接力发生器的动作器,可以根据输入与输出进行最优的反馈控制,使悬架有最好的减震特性,以提高汽车的平顺性和操纵稳定性。
它由弹性元件C和一个力发生器Fe组成。
半主动悬架可看作由可变特性的弹簧和减振器组成的悬架系统,虽然它不能随外界的输入进行最优的控制和调节,但它可按存储在计算机的各种条件下最优弹簧和减振器的优化参数指令来调节弹簧的刚度和减振器的阻尼状态。
它由弹性元件 C 和一个一个阻尼系数能在较大范围内调节的阻尼器组成。
电子技术控制汽车悬架系统主要由(车高、转向角、加速度、路况预测)传感器、电子控制ECU、悬架控制的执行器等组成。
系统的控制功能通常有以下三个:1 车高调整当汽车在起伏不平的路面行驶时,可以使车身抬高,以便于通过;在良好路面高速行驶时,可以降低车身,以减少空气助力,提高操纵稳定性。
2 阻尼力控制用来提高汽车的操纵稳定性,在急转弯、急加速和紧急制动情况下,可以抑制车身姿态的变化。
3 弹簧刚度控制改变弹簧刚度,使悬架满足运动或舒适的要求。
采用主动式悬架后,汽车对侧倾、俯仰、横摆跳动和车身的控制都能更加迅速、精确,汽车高速行驶和转弯的稳定性提高,车身侧倾减少。
制动时车身前俯小,启动和急加速可减少后仰。
即使在坏路面,车身的跳动也较少,轮胎对地面的附着力提高。
一.主动式液压悬架电子控制的主动式液压悬架能根据悬架的质量和加速度等,利用液压部件主动地控制汽车的振动。
主动式液压悬架在轿车上的布置如图所示,在汽车重心附近安装有纵向、横向加速度和横摆陀螺仪传感器,用来采集车身振动、车轮跳动、车身高度和倾斜状态等信号,这些信号被输入到控制单元ECU,ECU 根据输入信号和预先设定的程序发出控制指令,控制伺服电机并操纵前后四个执行油缸工作。
二.主动式空气悬架在电子控制的主动式空气悬架系统中,微机根据传感器送来的信号和驾驶员给予的控制模式经过运算分析后向悬架发出指令,悬架可以根据微机给出的指令改变悬架的刚度和阻尼系数,是车身在行驶过程中保持良好的稳定性能,并且将车身的振动响应控制在允许的范围内。
一般说来,主动式空气悬架的控制内容包括车身高度、减振器衰减力、弹簧弹性系数等三项;1车高的控制;分标准、升高和只升高后轮三种工作状态;2减震器的衰减力控制分低、中、高三档;3空气弹簧的弹性系数分软、硬两档。
空气悬架电子控制系统的工作原理;用空气压缩机形成压缩空气,并将压缩空气送给弹簧和减震器的空气室中,以此来改变车辆的高度。
在前轮和后轮的附近设有车高传感器,按车高传感器的输出信号,微机判断出车辆高度,再控制压缩机和排气阀,使弹簧压缩或伸长,从而控制车辆高度。
在减震器内设有电动机,电动机受微机的信号控制。
利用电动机可以改变通气孔的大小,从而改变了衰减力的大小。
具体说来,在汽车仪表板上有空气悬架系统的开关,利用开关可以形成6 种不同的工作方式。
自动变速器自动变速器的选挡杆相当于手动变速器的变速杆,一般有以下几个挡位:P(停车)、R(倒挡)、N(空挡)、D(前进)、S(or2,即为 2 速挡)、L(or1,即为1 速挡)。
这几个挡位的正确使用对于驾驶自动变速器汽车的人来说尤其重要,下面就让我们一起来熟悉一下自动变速器各挡位的使用要领。
●P(停车挡)的使用发动机运转时只要选挡杆在行驶位置上,自动变速器汽车就很容易地行走。
而停放时,选挡杆必须扳入P 位,从而通过变速器内部的停车制动装置将输出轴锁住,并拉紧手制动,防止汽车移动。
●R(倒挡)的使用R位为倒挡,使用中要切记,自动变速器汽车不像手动变速器汽车那样能够使用半联动,故在倒车时要特别注意加速踏板的控制。
●N(空挡)的使用N位相当于空挡,可在起动时或拖车时使用。
在等待信号或堵车时常常将选挡杆保持在D位,同时踩下制动。
若时间很短,这样做是允许的,但若停止时间长时最好换入N 位,并拉紧手制动。
因为选挡杆在行驶位置上,自动变速器汽车一般都有微弱的行驶趋势,长时间踩住制动等于强行制止这种趋势,使得变速器油温升高,油液容易变质。
尤其在空调器工作、发动机怠速较高的情况下更为不利。
有些驾驶员为了节油,在高速行驶或下坡时将选挡杆扳到N 位滑行,这很容易烧坏变速器,因为这时变速器输出轴转速很高,而发动机却在怠速运转,油泵供油不足,润滑状况恶化,易烧坏变速器。
●D(前进挡)的使用正常行驶时将选挡杆放在D 位,汽车可在1~4 挡(或3 挡)之间自动换挡。
D位是最常用的行驶位置。
需要掌握的是:由于自动变速器是根据油门大小与车速高低来确定挡位的,所以加速踏板操作方法不同,换挡时的车速也不相同。
如果起步时迅速将加速踏板踩下,升挡晚,加速能力强,到一定车速后,再将加速踏板很快松开,汽车就能立即升挡,这样发动机噪声小,舒适性好。
D 位的另一个特点是强制低挡,便于高速时超车,在D 位行驶中迅速将加速踏板踩到底,接通强制低挡开关就能自动减挡,汽车很快加速,超车之后松开加速踏板又可自动升挡。
●S、L 位低挡的使用自动变速器在S 位或L 位上处于低挡范围,可以在坡道等情况下使用。
下坡时换入S位或L位能充分利用发动机制动,避免车轮制动器过热,导致制动效能下降。
但是从D位换入S位或L位时,车速不能高于相应的升挡车速,否则发动机会强烈振动,使变速器油温急剧上升,甚至会损坏变速器。
另外在雨雾天气时,若路面附着条件差,可以换入S位或L 位,固定在某一低挡行驶,不要使用能自动换挡的位置,以免汽车打滑。
同时必须牢记,打滑时可将选挡杆推入N位,切断发动机的动力,以保证行车安全。
SuspensionThe modern of in the car has two kinds of suspension system, a kind of suspension is from move , another a kind of suspension is active .From move an a function for, is from spring coil, reducing flapping machine( reduce to the flap ), leading to organization etc. constituting, it is vibration that impact to dies down roadecause this kind of can produce the function dint by oneself, therefore call active of .The active of is more than ten years to develop of, from a kind of new of that computer control, have three terms:(1) having to be able to produce the motive source of the function dint;(2) carry out a piece can deliver this kind of function dint combines it can continue the work;(3) have the variety spreads to feel the machine combines to concentrates the relevant data to micro-computer to proceed to carry to calculate to combine the decision controls the way.Therefore, active a technique for gathering together mechanics with electronics knowledge, is a kind of high technique that compare t pass the carriage dint, the reduces from the impact dint but causable loading system.Among them the spring coil rises primarily the function that deceleration pound at dint, reduce the main function that flap the machine is a to reduce the vibration.Because this kind of be driven by outside dint but rise function of, so call from move .But active a device for of in the control link installing can producing take out moving, adopt a kind of repress in suppressing the dint by dint the road face the impact dint of the carriage and the inclination dint of the carriage.B o sophisticate to equip.For example equip active an axis for of France snow iron dragonmulberry,the car's a system is speed, carriage that a micro-computer, have on the of the 5 kinds of spreading feels machine, distinguish to deliver to micro-computer the car soon, the ex- round system moves the pressure and step to move the accelerator pedal perpendicular flap and frequencies, change direction the dish angle and change direction flat-out etc. data directionally.The computer receives these datases continuously and with in advance the critical value that set up proceeds the comparison, choosing the homologous an appearance.At the same time,on micro-computer independence control.each a car wheel of carry out a dollar a for, passing the control reduce to flap the machine inside hydraulic-pneumatic variety creation take out moving, from but can on any time, any car wheel creation meeting request a sport.Therefore, the mulberry bridge car has various driver's modes chooses, driving as long as pull to move to locate the vice- the " normal" on the instrument panel or" sport" button, car will establishes automatically in the best an appearance, in order to best and comfortable function.Moreover, active a function for having carriage sport of control.When the car system moves or turns a corner of inertial cause When the spring coil transform, active a dint for would producing first and opposite anti- in the dint of , reduce the variety of the carriage position.For example Germany speeds 2000 CLs type sport car, be, the vehicle turns a corner an inclination for spreading feeling machine would immediately examining carriage with horizontal acceleration, computer according to information that spreading and feeling machine, with in advance the critical value that set up proceeds the comparison computes, immediately certain at where full general how big of loading and adding to .The active in car a liquid presses with the air type:From the angle demarcation of the control dint, the of can is divided into passive of , active of in half with active of . Current, the automotive a system has the spring coil with reduce to flap the machine mostly, theincapable source inside a system insupplies the device, its flexibility can't change with the exterior work with the , therefore calling that this kind of is passive of .Active an action for thering is direct dint in conduct and actions taking place machine, can according to input and output the superior feedback of proceeding control, making a the of has to reduce to shake the characteristic bestly, toing increase the automotive and going smoothly with manipulate the stability.It constitutes with a dint occurrence machine Fe from the flexibility a C.Half active a spring coil for can seeing making from variable characteristic with machine that reducing and flapping the a system constitutes, although it can't proceed the superior control with regulate with the outsider importation, it can press saving under every kind of term of the calculator superior spring coil with reduce to flap the machine excellent to turn the parameter instruction to regulate the spring coil just a the appearance of for with reducing flapping machine.It from flexibility a C with a per coefficient can the machine of regulated within the scope of big constitute.The electronics technique control car a system is main from( the car is high and change direction the Cape, acceleration, road the estimate) spread to feel the machine, electronics control ECU, of control of carry out machine etc. constitute.The control function of the system usually has below three: 1 the car is high to adjust to be the car at rise and fall When the uneven road drive, can make carriage jacked up, in order to in pass;When the good road mades good time, can lower the carriage, to reduce the air help, increase to manipulate the stability.Dint controls is used to increase to manipulate the stability automotively, in the flashback curved, nasty accelerates to move with the urgent system circumstance next, can rr is to the side , horizontal put the flutter with the control of the carriage can more quick, precision, the car mades good time with the stability exaltation of the turn, carriage side reduce.The ex- in carriage is small when system move, starting with nasty accelerate can after reducing .Even in the bad road, the flutter of the carriage too less, the tire increases to the adhesive strength of the ground.One.The active type liquid presses ofThe active type liquid that electronics control presses a quantity for can according to of with acceleration etc., making use of the liquidpress the parts actively automotive vibration in control.The active type liquid presses a the of arrange to is sepress the variety of the carriage.3 spring coil just a control changes spring coil just degree, makea contented sport or comfortable request.Adopt an empress, cahown as diagram on the car, having in the nearby gearing in center of gravity in car lengthways, horizontal acceleration with horizontal put the top preads to feel machine, use to collect the carriage the vibration, the car wheel jumps about, carriage high degree with tilt to one side appearance etc. signal, these signalses is inputed control unit ECU, ECU according to input signal with in advance the procedure that set up issues to control the instruction, controling the servo electrical engineering combines to manipulate in front and back four carry out a work. two.Active type air .In electronics control of active type air a system, tiny machine according to spread to feel the machine changeses to an instruction for issuing the instruction, the of can give according to the tiny machine after delivering of the signal with the control mode that pilot give has been carries to calculate the analysis of just degree with the coefficient of , is a carriage within the scope of drives to keeps in the process good and stable function, and respond to the vibration of the carriage to control at allow of.Say generally, the control contents of the active type air includes the carriage high degree and reduce to flap the machine reduces the dint, spring coil flexibility coefficient waits three item;1 high control in car;Cent standard, go up with only after going up a three kinds of works appearance;2 reduce the that shake the machine reduce the dint control the cent low, inside, high three file;3 the cent of flexibility coefficient of air spring coilses are soft and hard two file.The air an electronics controls the work principle of the system;Use the air compressor formation compressed air, combine to give the compressed air to spring coil with the air room that reducing and shaking the machine inside, changes with this the high degree of the vehicle.Fore a neighborhood for with empress round establishes the carthe high spreading feels machine, press car the high spreading the exportation signal that feels the machine, the tiny machine judges the vehicle the high degree, then control compressor with line up the spirit valve, make spring coil compression or elongation, from butcontrol vehicle high degree.Establish the electric motor in reduce shook machine, the electric motor suffers the signal control of the tiny machine.Making use of the electric motor can change the size of the air hole . Say in a specific way, switch in last free spirit in instrument panel in car a system, make use of the switch can become 6 kinds of different works method.The automatic gearboxThe automatic gearbox chooses to block the pole the equal to moving the stick shift of the gearbox, having generally below several blocks:P( parking), R( pour to block), N( get empty to block), D( go forward), S( or2, namely for 2 block soon), L.( or1, namely for 1 block soon)This several an usage for blocking a right usages coming driver the automatic gearbox is automotive of person to say particularly important, underneath let us very much familiar with once automatic gearbox eachly blockings main theme.The usage of the P ( the parking blocks)The launches the luck turns as long as choose to block the pole in driving the position, automatic gearbox car run about very easily.But park, choose to block the pole must pull into of P, from but pass the internal parking system in gearbox moves the device will output the stalk lock lives, combining to tense the hand system move, preventing the car ambulation.The usage of the R( pour to block)R a control for is pouring blocking, using inside wanting slicing recording, automatic gearbox car unlike moving gearbox car so can using half moving, so while reversing the car wanting special attention accelerating pedal.The usage of the N( get empty to block)The N is equal to get empty to block, can while starting or hour of trailer usage.At wait for the signal or block up the car will often oftenchoose to block the pole keeps in the of D, trampling at the same time the next system move.If time is very short, do like this is an admission of, but if stop the time long time had better change into of N, combine to tense the hand system moves.Because choose to block the pole in driving the position, the automatic gearbox car has generally and all to drive the trend faintly, long hours trample the system move same as a deterrent this kind of trend, make gearbox oil gone up, the oil liquid changes in character easily.Particularly in the air condition machine work, launch the soon higher circumstance in machine bottom more disadvantageous.Some pilots for the sake of stanza oil, at made good time or go down slope will choose to block the pole pull the of N skids, this burn the bad gearbox very easily, launching the machine to revolves soon in the however because the gearbox outputs at this time the stalk turns soon very high,, the oil pump provides the oil shortage, lubricating the condition worsen, burn the bad gearbox easily.The usage of the D( go forward to block)Will choose to block when is normal to drive the pole put in the of D, car can at 1 4 block( or 3 block) its change to block automatically.The of D drives the position most in common usely.What demand control is:Because the automatic gearbox is soon high and low with car to come to make sure to block according to the accelerator size a, so accelerate the pedal operation method is different, changing to block the hour of the car is soon too not same alike.If start hour quick accelerate the pedal tramples the bottom, rising to block the night, accelerating the ability is strong, arriving certain car soon behind, then will accelerate the pedal loosen to open very quickly, car can rise to block immediately, launch like this the machine voice is small, comfortable good.The another characteristics of the D is a compulsory low blocking, easy to high speed the hour overtakes a car, will accelerate quickly in of D drove the pedal trample after all, connect the compulsory low fend off the pass and then can reduce to block automatically, the car accelerates very quickly, after overtaking a car loosen to open the pedal of acceleration to can rise to block automatically again.The usage of the S, of L low the usage that blockThe automatic gearbox in in is placed in the low blocking the scope on of S or of Ls, can usage under an etc. circumstance.It change to can make use of to launch well into of S or of Ls the mechanism move, avoiding the car wheel system move the machine over hot, cause the system move the effect descent while going down slope.But change into from the of D of S or of L, car soon can't higher than rise to block the car homologously soon, otherwise strong vibration in opportunity to launch, make gearbox oil hoicked, even will damage the gearbox.The is another at rain fog weather hour, if the road adheres to the term bad, can change into a position for or of L, fixing at somely first lowly blocking driving, doing not use can automatically changing blocking, in order to prevent the car beats slippery.Must keep firmly in mind at the same time, beat the slippery hour can will choose to block the pole pushes into a motive for, cutting off launching machine, toing guarantee a car the safety.。