驱动桥和差速器外文文献翻译

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差速器和车桥--中英文翻译

差速器和车桥--中英文翻译

DIFFERENTIAL AND REAR AXLESThe differential is part of the rear-axle-housing assembly,which includes the differential,rear axles,wheels,and bearing.If the car were to be driven in a straight line without having to make turns,then no differential would be necessary.However,when the car rounds a turn,the outer wheel must travel farther than the inner wheel.The differential permits the two rear wheels to rotate different amounts when the car goes around a turn , while still delivering power to both rear wheels.The rear axles are attached to the wheels and have bevel side gears on their inner ends.The differential case is assembled on the left axle but can rotate on a bearing independently of the axle.The differential case supports the differential-pinion gear on a shaft,and this gear meshes with the two bevel gears.The fing gear is attached to the differential case so that the case rotates with the fing gear when the latter is driven by the drive pinion.The driving power enters the differential through the drive pinion on the end of the propeller shaft.The drive pinion is meshed with a large ring gear so that the ring gear revoves with the pinion.Attached to the ring gear is a differential-pinion shaft on which are assembled two differential-pinion gears.Each rear car wheel has a separate axle, and there are two side gears splined to the inner ends of the two wheel axles.The two side gears.When the car is on a straighet road ,the two differential-pinion gears do not rotate on the pinion shaft ,but they do exert pressure on the two side gears turn at the same speed as the ring gear ,causing both rear wheels to turn at the same speed,also.When the car rounds a curve ,the outer wheel must turn faster than the inner wheel,To permit this,the two pinino gears rotate on their pinion shaft,transmitting more turning movement to the outer side gear that to the inner side gear.Thus,the side gear on the outer-wheel axle turns more rapidly than the side gear on the inner wheel axle.This permits the outer wheel to turn more rapidly while the car is rounding the curve.There are two basic types of axle:deed axles and live axle.The dead axle does not rotate; the wheel rotates on it.A common exmple is the axle on a horse-drawn wagon.Live axles are attached to the wheel so that both the wheel and the axle rotate together.Live axles are classified according to the manner in which they are supported:semifloating, three-quarer-floating,and full-floating.AUTOMOBILE SYSTEMThe fuel system has the job of supplying a combustible mixture of air and fuel to the engine. The fuel system must vary the proportions of air and fuel to suit different operating conditions. When the engine is cold, for example, then the mixture must be rich(have a high proportion of fuel).The reason for this is that the fuel does not vaporize rapidly at low temperatures. Therefore, extra fuel must be added to the mixture so that there will be enough vaporized fuel to form a combustible mixture.The fuel system consists of the fuel tank, fuel pump, fuel filter, carburetor, intake manifold, and fuel lines, or tubes, connecting the tank, pump, and carburetor. Some gasoline engines use a fuel-injection system; in this system, a fuel-injection pump replaces the carburetor.The fuel tank, in which gasoline is stored, is normally located at the rear of the vehicle. It is made of sheet metal and is attached to the frame.A fuel pump delivers fuel from the tank to the carburetor. There are two general types of fuel pump, mechanical and electric.The fuel system has filters and prevent dire in the fuel from entering the fuel pump or carburetor. Dirt could, of course, prevent normal operation of these units and cause poor engine performance.The carburetor is essentially a mixing device which mixes liquid gasoline with air. In this process, it throws a fine spray of gasoline into air passing through the carburetor on its way to the engine. The gasoline vaporizes and mixes with the air to form a highly combustion chambers, where it is ignited. It burns, causing the engine to produce power. The mixture must be of varying degrees of rich nice to suit engine operating conditions.It must be rich(have a higher percentage of fuel)for starting, acceleration, and high-speed operation. And it should lean to(become less rich)for operation at intermediate speed with a worm engine. The carburetor has several different circuits, or passages, through which fuel and air-fuel mixture flow under different operating conditions to produce the varying richness of the air-fuel mixture.The purpose of the cooling system is to keep the engine at its most efficient operating temperature at all engine speeds and all drilling conditions.A great deal of heat is produced in the engine by the burning of the air-fuel mixture. Some of this heat escapes from the engine through the exhaust gases(the hot gases left after the gasoline is burned). But enough remains in the engine to cause serious trouble unless removed by some other means. The cooling system takes care of this additional heat.The cooling system is built into the engine. There are hollow spaces around each engine cylinder and combustion chamber. These hollow spaces are called waterjackets, since they are filled with water. When the engine is running, the water takes heat from the engine, becoming hot in the process.A water pump pumps the hot water from the engine water jackets into the radiator. The radiator has two sets of passages. One set carries air(pulled through by car motion and the engine fan). As the hot water passes through, it gives up its heat to the air passing through. The cooled water then reenters the engine, where it can pick up more heat. In operation, water continuously circulates between the engine and radiator, carrying heat from the engine temperatures are prevented.Two general types of cooling systems are used, air cooling and liquid cooling. The liquid cooling system consists of water pumps, water jackets, engine fan, radiator and so on. The water pump, driven by a belt from the engine crankshaft, circulates the cooling liquid between the radiator andengine water jackets. The cooling liquid is water. Antifreeze compounds are added to the water during the winter. The water jacket are cast into the cylinder blocks and heats. The engine fan is usually mounted on the water-pump shaft and is driven by the same belt that drives the pump shaft and the generator. The purpose of the fan is to provide a powerful draft of air through the radiator. The radiator is a device for holding a large volume of air so that heat will transfer from the water to the air. The radiator core is divided into two separate compartments; water passes through one, and air passes through the other.The ignition system is part of the electric system of the automobile. Its purpose is to produce high-voltage surges(up to 20 000 volts)and to deliver them to the combustion chambers in the engine. These high-voltage surge surges then cause electric sparks in the combustion chambers. The sparks ignite, or set fire to, the air-fuel mixture in the combustion chambers so that it burns and cause the engine ton operate.The ignition system consists three basic parts: the ignition distributor, the ignition coil, and the spark plug, together with the connecting wires. When the engine is running, the ignition coil is repeatedly connected, it becomes loaded with electrical energy. Then, when it is disconnected, the “load” of electrical energy is released in a high-voltage. This surge flows through the wiring to the spark plug in the engine cylinder that is ready to fire.You must understand that all this takes place very rapidly. At high speed, the whole series of events happens in less than one three-hundredth of a second. That is, there will be as many as 300 of these events every second that the engine is running at high speed.Some systems use transistors to reduce the load on the distributor contract points. Other systems do not have contract points use instead a combination of transistors and a magnetic pick-up in the distributor.The ignition distributor has two jobs. First, it closes and opens the circuit between the battery and the ignition coil. The distributors second job is to distribute each high-voltage surge to the correct spark plug at the correct instant by means of the distributor rotor and cap and secondary wiring.There are two basic types of distributor:(1)the type using contact points to close and open the coil primary circuit;(2)the type using a magnetic pick-up and a transistor control unit to interrupt the current flow of the coil primary circuit.Automobile engines are not self-starts. In order to start them, the engine crankshaft must be turned over by some outside means so as to(a)admit air-fuel mixture to the cylinder, and(b)cause the mixture to fire.In the case of automobile engines, the mixture in the cylinder, after being compressed, must be not enough to ignite. This requires that the engine be turned over with sufficient speed. If the engine is turned over too slowly, the unavoidable small leaks past the piston rings and also through the intake and exhaust valves of four-circle engines will permit a substantial part of the fuel-air mixture to escape during the compression stroke. Also, the heat loss from the compressed air to the cylinder walls will be greater at low speed because of the longer exposure. The escape of air and the loss of heat both result in a lower temperature at the end of compression. Therefore, there is a minimum speed which the engine must attain before ignition will occur and the engine will begin firing. The starting speed depends upon the type and size of the engine, its condition, and the temperature of the air entering engine.The starting system contains a cranking, or starting, motor and other accessories.The starting motor electrically cranks the engine for starting. It is a special direct-current motor operating on battery voltage and is mounted on the engine flywheel house. The starter changes the electrical current into the mechanical energy to push the crank-shaft round. By means of this, the engine can be started. The cranking motor consists of the commutator end head, holding the brushes; the field frame, into which the field windings are assembled around pole shoes; the drive housing, which house the drive assembly and supports the motor on the engine flywheel housing; the armature; and the drive assembly. Some cranking motors also have a solenoid that operates the shift lever.Cranking-motor controls have varied from a simple foot-operated pedal to automatic devices that close the cranking-motor circuit when the accelerator pedal is depressed.The present system that has been almost universally adopted for passenger cars and many other vehicles has starting contacts in the ignition switch. When the ignition key is turned against spring pressure past the ON position to START, the starting contacts close. This connects the cranking-motor solenoid or magnetic switch to the battery. After the engine starts and the ignition key is released, spring pressure returns it to the ON position.The starting motor should not be operated more than 5 seconds during each starting operating, for the sake of recovering the energy of battery. It will not be allowed to start it again until its stopped for fifteen seconds.The manual transmission shown in Fig.—1 provides a means of varying the relationship between the speed of the engine and the speed of the wheels .Varying these gear ratios allows the right amount of engine power at many different speeds.Manual transmission requires use of a clutch to apply and remove thetorque to the transmission input shaft. The clutch allows this to happen gradually a so that the car can be started from a complete stop.Modern manual transmissions do not disengage any of the forward drive gears, they are simply connected to their shafts through the use of “synchronizers”.Reverse is achieved reverse idler gears ,which are engaged to move the car backwards.Some manual transmissions have an “overdrive”. An overdrive is a mechanical unit bolted to rear of the transmission. It is usually known as the fifth gear .When you use it, it will reduce the engine speed by about one-third ,which maintaining the same road speed.In an automatic transmission, gear ratios are changed automatically. This eliminates the need for the driver to operate the clutch and manually “shift gears.”The typical automatic transmission combines a fluid torque converter , a planetary-gear system, and a hydraulic control system in a single unit. As car speed changes , various gear ratios between the crankshaft and the wheels are selected and then changed automatically. Automatic controls inside the transmission supply the proper ratio for the driving condition. In addition to the forward-gear ratios, neutral, and reverse, the automatic transmission has a PAPK position. This locks the transmission to prevent the car from moving or rolling away while parked.差速器和车桥差速器和后桥壳总成的一个部件,后桥壳总成包括差速器、后桥、车轮和轴承。

驱动桥汽车外文文献翻译、中英文翻译、外文翻译

驱动桥汽车外文文献翻译、中英文翻译、外文翻译

Driving Axleautomobile driving axleThe driving axle is one of cross bars supporting a vehicle, on which the driving wheels turn .The driving axle includes a housing ,an axle drive ,a differential , tow axle shafts (half axles ),and final drives (if any ) .The axle .or main, drive is a drive-line unit that increases the torque delivered by the transmission and transmits it to the driving wheels, via the differential. In automobiles, the axle drive shaft, usually called the propeller shaft.The axle drive may be a Single or a double-stage type, the former comprising a pair of gears and the latter .tow pairs of gear. Drive pinion I may be made integral with its shaft, or it may be detachable from the shaft. Driving gears and are usually made in the form of detachable gear rings that are bolted or riveted to the differential case .Alex drive bevel pinions and gears are made with helical teeth in order to reduce noise in operation.The tow-stage axle drive consists of a pair of bevel gears and a pair of spur gears. Drive bevel pinion drives bevel gear that is fixed to the flange of the intermediate shaft made integral with 2nd–stage driving spur gear .Gears meshes with driven spur gear which is fastened to the case rotates in taper roller bearings installed in the differential carrier that makes part of the driving axle housing.The differential is a drive-line unit that divides the torque applied to it between the tow axle shafts and allows one driving wheel to turn at a different speed from the other.The differential consists of case, cross or spider pinion .and side gears, also known as axle gears .the differential pinions are freely mounted on the cylindrical arms of the spider, which is held in the differential case, and remain in constant mesh with the differential side gears.When the automobile is moving down a straight and even road, both driving wheels meet with one and the same rolling resistance. In this case, axle driven gear, or differential ring gear, causes the differential case to rotate .when the differential case rotates pinions and their spider arms move around in a circle with tow differential side gears are meshed with the pinions, the side gears must rotate, causing the axle shafts and their associated driving wheels to turn. With equal resistance applied to each wheel, the differential pinions do not rotate. They apply equal torque to the side gears and therefore both driving wheels rotate at one and the same speed is unequal ,the differential pinions rotate on their spider arms as well as drive round with the differential case .supposing that one of the axle shaft is prevented from rotating ,the differential pinions would have to walk around the stationary side gear ,causing the other side gear to rotate at twice its normal speed .You can now see how the differential can allow one driving wheel to turn faster than the other .Whenever the automobile goes around a turn ,the outer driving wheel travels a greater distance than the inner drive wheel .the inner wheel speeds up proportionately ,thanks to the differential pinions that rotate on their spider arms and ,rolling around the slower side gear send more rotary motion to the outside wheel.The differential side gears are splined on to the inner ends of the axle shafts .The other ends of the shafts are attached to the driving wheel hubs by means of flanges .Trucks use full floating axle shafts .Such axle shafts are acted upon by torque only .All the other loads acting on the driving wheels are taken by the driving axle housing, because the wheel hubs are supported by bearings mounted on the housing.Driving axle of general-purpose wheeled tractorGeneral-purpose wheeled tractors are a four-wheel drive type, they have tow driving axles-front and rear .Both axles are similar in construction, expect for the housing. Each driving axle consist if a housing, an axle drive ,a differential ,and final drives .The front and rear-axles drives are interchangeable and comprise a pair of spiral bevel gears . The axle drive pinion is made integral with a shaft that issupported by tow taper roller bearings installed in axle drive pinion carrier .The latter is accommodated in differential carrier and is fixed to it by bolts. The flange of the axle drive pinion carrier is provided with threaded holes to fit puller screws that are used to remove the axle drive pinion carrier from the differential carrier .The position of the drive pinion relative to the centerline of the axle is adjust by means of a pack of shims placed under the flange of the drive pinion carrier Shims palace under the cone of the front bearing are used to adjust the preload on the drive pinion bearings. Splined to adjust the preload on the drive pinion shaft is universal-joint flange .The axle drive gear is bolted to the differential case flange.THE DIFFERENTIAL consists of case, four pinions, and tow side gears .The differential case comprise tow halves that are bolted together and supported by taper roller bearings installed in the differential carrier .Screwed in the bearings housing from the outside are nuts used to adjust the backlash between the ring gear and drive pinion teeth and the side bearing preload.Welded to the top of the driving axle housing at both its ends are spring pads .The housing of both its ends are spring axels are provided with filler ,overflow ,and drain holes closed by plugs .Both housing also have vents ,The rotating components of the driving axles are lubricated with transmission oil .As distinct from the automobiles considered in this text, all tractors include final drives in their power trains .The final drives of general-purpose wheel tractors are referred to as wheel-hub reduction gears.While transmitting power to the driving wheels, wheel-hub reduction can increase their torque .These are planetary reduction gear sets consist of sun gear ,or wheel ,three planet ,or pinion ,gears ,planet or pinion ,carrier .stationary internal ,or ring ,gear ,and housing.The sun gear is splined to the outer end of the axle shaft is splined to the differential side gear .The cylindrical planet gears are in constant mesh with both the sun gear and the ring gear and are free to rotate on roller bearings mounted on shafts that are attached to the planet carrier .The planet carrier is fasted to the reduction gear housing by means of studs and nuts .The flange of housing ,driving wheel brake drum13,and wheel hub are clamped together by bolts .The planet carrier and reduction gear housing form the driven part of the planetary gear set and rotate with the driving wheel of the tractor .The driving gear hub is supported by taper roller bearings mounted on axle shaft housing ,or axle sleeve .The axle sleeve is connected to the stationary ring gear by means of adapter hub that has internal splines and external teeth . The splines are meshed with matching splines on the axle sleeve, and the teeth are meshed with internal teeth ring gear.Wheels and its maintainModern wheeled tractors and automobiles use pneumatic-tired disc wheels. As a result of the driving wheel tires gripping the road, the rotary motion of the wheels is transformed into the translational motion of the tractor or automobile.According to their purpose, wheels are classified as driving .driven steerable, and combination types.Trucks and general-purpose wheeled tractors have all their wheels of one and the same size .Row-crop tractors have their rear wheels larger than the front wheels .The rear wheels carry the major proportion of the load due to the weight of the tractor .The front wheels are loaded lighter and this makes them easier to turn and provide good directional steering stability, which is essential for row-crop work.A TRUCK WHEEL consists of disc and flat base rim that is made integral with it, while the other flange is formed by detachable side ring that is held to the rim by split lock ring on the rim .which doubles as a side ring and a lock ring.The wheel disc is provided with holes for mounting the wheel on the wheel mounting bolts ,or wheel studs ,on the wheel hub ,where it is fixed by nuts .Both the holes and the nuts are tapered to ensure exact location of the wheel on its hub .The rear driving axles of trucks carry tow wheels at each end .The inner wheels are held to the hubs by cap nuts that are threaded both on the inside and on the outside .and the outer wheels are mounted on the cap nuts and fixed in place by taper nuts screwed on the nuts .The wheel nuts on the right side of truck have right-hand threads, whereas the nuts on the left side of the truck are threaded left-hand .The reason is to tighten the nuts, not loosen them, and thus prevent them from working loose on acceleration andbraking.An automobile pneumatic tire consists of casing, inner tube, and flap .The tire casing comprises tread, side walls, and beads .Tires for good roads use small tread patterns, while those for bad roads or cross –country service large tread patterns.The inner tube is made in the form of a hollow elastic rubber doughnut that is inflated with air after it is installed inside the tire and the tire is put on the wheel rim .The inner tube is inflated through tire valve that consists of housing 11,valve inside ,and cap .The valve housing is made of brass in the dorm of a flanged tube that is mounted in the inner tube by means of a washer and a nut and sticks out through a hole in the wheel .Some tire valve housing are of comprise construction :the upper part is made of brass and the lower part ,of rubber that is vulcanized on to the inner tube .The valve inside is a check valve that opens to let air in the inner tube when an air closed ,spring pressure and air pressure inside the tube hold the valve .When the valve is closed ,spring pressure and air pressure inside the tube hold the valve in its seat .It includes core with a rubber ring ,a plunger pin ,and a spring .The valve inside is Screwed in the tire valve housing and is closed by the cap Screwed on the housing.To the construction of the driving and steerable wheels, each wheel comprises hub , disc with rim ,and tire with inner tube .The rim is welded to the disc and the disc is bolted to the hub .The driving wheel tires are of low-pressure type and have heavy tread bars for better traction.The driving wheel hub is keyed to axle shaft and is fixed in place by means of bolted-on insert with worm whose threads mesh with the rack teeth cut in the half axle .By turning the worm one can change the position of the wheel on the axle shaft to obtain the desired track width .Before doing this ,it is necessary to jack up the rear part of the tractor to clear the wheels of the ground and loosen the bolts that hold the inserts to the wheels hubs .Should this adjustment prove insufficient ,the track width can further be increased by placing the wheels with the concaves of their discs facing inwards.On some row-crop tractors ,the rear wheel discs are bolts to lugs welded on the wheel rims .In this case ,the crack width can be changed by bolts the discs in alternative positions to the lugs .Also the concave wheel discs may be used either with the concave facing inwards or outwards.Trouble-free operation of automobiles and wheeled tractors largely depends on the condition of the tires. Therefore, during operation, one should adhere to following rules.Prevent fuel and, or oil from getting onto the tires. Cleans the tires regularly from dirt and remove all foreign articles, such as stones, form the treads. Do not apply brakes sharply, never start away form rest with a jerk, and avoid making sharp turns, for all this causes uneven wear of the tires. Do not allow excessive slipping of the driving wheels. When preparing your tractor or automobile for a long-term storage, jack up the wheels and put trestles under the axles or frame to relieve the tires.The service life of tires is expressed in terms of their mileage. For most bias (ordinary) truck tires, the guaranteed mileage amounts to 50000 km. Observing the above rules will help prolong the useful service life of tires.驱动桥汽车的驱动桥驱动桥是一个支撑车辆的十字交叉的轴,它可以驱动车轮运动。

汽车差速器中英文对照外文翻译文献

汽车差速器中英文对照外文翻译文献

中英文对照外文翻译(文档含英文原文和中文翻译)Failure analysis of an automobile differential pinion shaft AbstractDifferential is used to decrease the speed and to provide moment increase for transmitting the movement coming from the engine to the wheels by turning it according to the suitable angle in vehicles and to provide that inner and outer wheels turn differently. Pinion gear and shaft at the entrance are manufactured as a single part whereas they are in different forms according to automobile types. Mirror gear which will work with this gear should become familiar before the assembly. In case of any breakdown, they should be changed as a pair. Generally, in these systems there are wear damages in gears. The gear inspected in this study has damage as a form of shaft fracture.In this study, failure analysis of the differential pinion shaft is carried out. Mechanical characteristics of the material are obtained first. Then, the microstructure and chemical compositions are determined. Some fractographic studies are 2005 Elsevier Ltd. All rights reserved.Keywords: Differential; Fracture; Power transfer; Pinion shaft1. IntroductionThe final-drive gears may be directly or indirectly driven from the output gearing of the gearbox. Directly driven final drives are used when the engine and transmission units are combined together to form an integral construction. Indirectly driven final drives are used at the rear of the vehicle being either sprung and attached to the body structure or unsprung and incorporated in the rear-axle casing. The final-drive gears are used in the transmission system for the following reasons [1]:(a) to redirect the drive from the gearbox or propeller shaft through 90°and,(b) to provide a permanent gear reduction between the engine and the driving road-wheels.In vehicles, differential is the main part which transmits the movement coming from the engine to the wheels On a smooth road, the movement comes to both wheels evenly. The inner wheel should turn less and the outer wheel should turn more to do the turning without lateral slipping and being flung. Differential, which is generally placed in the middle part of the rear bridge, consists of pinion gear, mirror gear, differential box, two axle gear and two pinion spider gears.A schematic illustration of a differential is given in Fig, 1. The technical drawing of pinion the fractured pinion shaft is also given in Fig, 2, Fig. 3 shows the photograph of the fractured pinion shaft and the fracture section is indicated.In differentials, mirror and pinion gear are made to get used to each other during manufacturing and the same serial number is given. Both of them are changed on condition that there are any problems. In these systems, the common damage is the wear of gears [2-4]. In this study, the pinion shaft of the differential of a minibus has been inspected. The minibus is a diesel vehicle driven at the rear axle and has a passenger capacity of 15 people. Maximum engine power is 90/4000 HP/rpm, and maximum torque is 205/1600 Nm/rpm. Its transmission box has manual system (5 forward, 1 back). The damage was caused by stopping and starting the minibus at a traffic lights. In this differential, entrance shaft which carries the pinion gear was broken. Various studies have been made to determine the type and possible reasons of the damage. These are:•studies carried out to determine the material of the shaft;•studies carried out to determine the micro-structure;•studies related to the fracture surface.There is a closer photograph of the fractured surfaces and fracture area in Fig. 4. The fracture was caused by taking out circular mark gear seen in the middle of surfaces.2. Experimental procedureSpecimens extracted from the shaft were subjected to various tests including hardness tests and metallographic and scanning electron microscopy as well as the determination of chemical composition. All tests were carried out at room temperature.2.1 Chemical and metallurgical analysisChemical analysis of the fractured differential material was carried out using a spectrometer. The chemical composition of the material is given in Table 1. Chemical composition shows that the material is a lowalloy carburizing steel of the AISI 8620 type.Hardenability of this steel is very low because of low carbon proportion. Therefore, surface area becomes hard and highly enduring, and inner areas becomes tough by increasing carbon proportion on the surface area with cementation operation. This is the kind of steel which is generally used in mechanical parts subjected do torsion and bending. High resistance is obtained on the surface and high fatigue endurance value can be obtained with compressive residual stressby making the surface harder [5-7].In which alloy elements distribute themselves in carbon steels depends primarily on the compound and carbide forming tendencies of each element. Nickel dissolves in the αferrite of the steel since it has less tendency to form carbides than iron Silicon combines to a limited extent with the oxygen present in the steel to form nonmetallic inclusions but otherwise dissolves in the ferrite. Most of the manganese added to carbon steels dissolves in the ferrite. Chromium, which has a somewhat stronger carbide-forming depends on the iron, partitions between the ferrite and carbide phases. The distribution of chromium depends on the amount of carbon present and if other stronger carbide-forming elements such as titanium and columbium amount of carbon present and if other stronger carbide-forming elements such as titanium and columbium are absent. Tungsten and molybdenum combine with carbon to form carbides is there is sufficient carbon present and if other stronger carbide-forming elements such da titanium and columbium are absent. Manganese and nickel lower the eutectoid temperature [8]. Preliminary micro structural examination of the failed differential material is shown in Fig. 5. It can be seen that the material has a mixed structure in which some ferrite exist probably as a result of slow cooling and high Si content. High Si content in this type of steel improves the heat treatment susceptibility as well asan improvement of yield strength and maximum stress without any reduction of ductility [9]. If the micro-structure cannot be inverted to martensite by quenching, a reduction of fatigue limit is observed.There are areas with carbon phase in Fig. 5(a). There is the transition boundary of carburization in Fig. 5(b) and (c) shows the matrix region without carburization. As far as it is seen in there photographs, the piece was first carburized, then the quenching operation was done than tempered. This situation can be understood from blind martensite plates.2.2 Hardness testsThe hardness measurements are carried out by a MetTest-HT type computer integrated hardness tester. The load is 1471 N. The medium hardness value of the interior regions is obtained as obtained as 43 HRC. Micro hard-ness measurements have been made to determine the chance of hardness values along cross-section be-cause of the hardening of surface area dueto carburization. The results of Vickers hardness measurement under a load of 4.903 N are illustrated in Table 2.2.3 Inspection of the fractureThe direct observations of the piece with fractured surfaces and SEM analyses are given in this chapter. The crack started because of a possible problem in the bottom of notch caused the shaft to be broken completely. The crack started on the outer part, after some time it continued beyond the centre and there was only a little part left. And this part was broken statically during sudden starting of the vehicle at the traffic lights. As a characteristic of the fatigue , there are two regions in the fractured surface. These are a smooth surface created by crack propagation and a rough surface created by sudden fracture. These two regions can be seen clearly for the entire problem as in Fig. 4. The fatigue crack propagation region covers more than 80% of the cross-section.Shaft works under the effect of bending, torsion and axial forces which affect repeatedlydepending on the usage place. There is a sharp fillet at level on the fractured section. For this reason, stress concentration factors of the area have been determined. K t = 2.4 value (for bending and tension), and K t = 1.9 value (for torsion) have been acquired according to calculations. These are quite high values for areas exposed to combined loading.These observations and analysis show that the piece was broken under the influence of torsion with low nominal stresses electron microscopy shows that the fracture has taken place in a ductile manner (Fig.6). There are some shear lips in the crack propagation region which is a glue of the plastic shear deformations. Fig. 7 shows the beach marks of the fatigue crack propagation. The distance between any lines is nearly 133 nm.3. ConclusionsA failed differential pinion shaft is analysed in this study. The pinion shaft is produced from AISI 8620 low carbon carburising steel which had a carbursing, quenching and tempering heat treatment process. Mechanical properties, micro structural properties, chemical compositions and fractographic analyses are carried out to determine the possible fracture reasons of the component. As a conclusion, the following statements can be drawn:•The fracture has taken place at a region having a high stress concentration by a fatigue procedure under a combined bending, torsion and axial stresses having highly reversible nature.•The crack of the fracture is initiated probably at a material defect region at the critical location.•The fracture is taken place in a ductile manner.•Possible later failures may easily be prevented by reducing the stress concentration at the critical locationAcknowledgementThe author is very indebted to Prof. S. Tasgetiren for his advice and recommendations during the srudy.References[1]Heisler H. Vehicle and engine technology. 2nd ed. London: SAE International; 1999.[2]Makevet E, Roman I. Failure analysis of a final drive transmission in off-road vehicles. EngFailure Anal 2002;9:579-92.[3]Orhan S, Aktu ¨rk N. Determination of physical faults in gearbox through vibrationanalysis. J Fac Eng Arch Gazi University 2003;18(3):97–106..[4]Tasgetiren S, Aslantas ? K, Ucun I. Effect of press-fitting pressure on the fatiguedamages of root in spur gears. Technol Res: EJMT 2004;2:21–9.[5]Nanawarea GK, Pableb MJ. Failures of rear axle shafts of 575 DI tractors. EngFailure Anal 2003;10:719–24.[6]Aslantas K, Tasgetiren S. A study of spur gear pitting formation and life prediction.Wear 2004;257:1167–75.[7]Savas V, O ¨ zek C. Investigation of the distribution of temperature on a shaft withrespect to the deflection. Technol Res: EJMT 2005;1:33–8.[8]Smith FW. Principles of materials science and engineering. 3rd ed. USA: McGraw-HillSeries; 1996. p. 517–18.[9]ASM metal handbook, vol. 1. Properties and selection, irons, steels, and highperformance alloys; 1991.[10]Voort GFV. Visual examination and light microscopy. ASM handbook metallographyand microstructures. Materials Park (OH): ASM International; 1991. p. 100–65.汽车差速器小齿轮轴的失效分析摘要差速器是用来降低速度增加扭矩并根据合适的角度向两轮传递动力。

自动变速器与驱动桥概述 英文文献加中文翻译

自动变速器与驱动桥概述 英文文献加中文翻译

AUTOMATIC TRANSMISSION & TRANSAXLEOVERVIEWby Kyle McFaddenAutomatic transmissions are highly complex hyrdomechanical devices. Diagnosing and repairing them requires nothing less than an ASE master mechanic. The automatic transmission provides automated selection of forward gears in a motor vehicle. The automatic transmission is able to select the correct forward gear for efficient engine operation based on vehicle speed, throttle position, and engine load. The automatic transmission components consist of transmission case, torque converter, fluid pump, planetary gear set, clutch packs and/or band assemblies, control valves, transmission mainshaft, extension housing and various small parts.The transmission case is manufactured of cast aluminum. It houses the internal components of the automatic transmission and provides a mounting surface for attachment to the engine block. The torque converter is bolted to a type of flywheel called a flex plate. The flexplate in turn, is bolted to the rear of the crankshaft. The torque converter provides a means to transmit engine power into the transmission.Refer to an auto repair manual for a diagram showing the details of your vehicle’s torque converter assembly.The torque converter is a doughnut shaped device that is filled with fluid. When the engine is running, the torque converter spins, rotating and pressurizing the fluid using internally mounted blades. The spinning fluid rotates a turbine that is connected to the transmission mainshaft. A separate internal set of blades called a stator helps to direct the fluid into the turbine. The operation of the torque converter can be compared to a powered air fan spinning a non powered air fan. The powered fan will generate moving air, directed at the non powered fan blade, causing it to rotate. The powered fan becomes the driving member, while the non powered fan becomes the driven member. If the air is moving slow enough, very little torque is transmitted from the driving member to the driven member. If you wanted, you could easily stop the rotating fan blade of the non powered fan. However, if the powered fan were to operate at high speed, the non powered fan would be rotating at a much higher speed, making it more difficult to stop. This is the same principal that allows an automatic transmission equipped vehicle to idle in gearand drive down the road without using a mechanical clutch. At idle speed, fluid pressure is low, transmitting very little engine torque through the transmission. When the engine speed is raised, fluid speed and pressure increases, allowing more engine torque to be directed to the transmission. Most torque converters contain an internal locking clutch that is applied at cruise speed. This clutch, called a torque converter clutch, eliminates the slippage that occurs with a torque converter. The torque converter clutch is used as a fuel saving device, and to reduce the amount of heat generated in the transmission. When troubleshooting poor MPG issues, one culprit is a faulty torque converter, though poor MPG would also be present with shifting issues if the torque converter is the cause.Forward speeds and reverse are provided by a gear set called the planetary gears. The planetary gear set consists of a central gear, called the sun gear, placed inside a large gear called an internal gear. Rotating between the internal gear and the sun gear, are small gears, held in a carrier, known as planetary gears. Different gear ratios are made possible by holding one component of the planetary gear set and allowing the other to rotate. For example, if the sun gear were held, the internal gear would be rotated by the planetary gears revolving around the motionless sun gear. This would cause the internal gear to rotate at low speed, while the planetary gears move much faster. This would provide a low gear function for the transmission, since the slow moving internal gear would be used to transmit power to the driving wheels.An internal transmission oil pump is driven by the rotation of the torque converter. The oil pump pressurizes and circulates the transmission fluid used for the operation and lubrication of the transmission. The pressure created by the pump is often referred to as line pressure. Line pressure is utilized by the transmission to signal shift points and operate various transmission components.Bands and clutches are used to hold the components of the planetary gear set to in order to provide different forward gear ratios or reverse. They are operated by line pressure that is directed to a specific band or clutch pack by the transmission shift control valves. The shift control valves operate by responding to changes in linepressure based upon the operation of input devices that signal road speed, throttle position, and engine load. Correcting shifting issues may not involve a costly auto repair job; it may be as simply as adjusting the bands.The input devices used for transmission shift control are the governor, throttle valve, and vacuum modulator. The governor provides road speed information to the transmission to control shift points. It works by increasing line pressure as road speed increases. The throttle valve is connected by linkage to the throttle of the engine. The throttle valve modifies line pressure based on throttle position. This information is needed to vary shift points in response to driving conditions. When the throttle is moved to wide open, the throttle valve will cause send a line pressure signal to the control valves to delay shifting until higher road speed. The vacuum modulator changes shift feel in response to engine load. Since engine intake manifold vacuum changes in response to engine load, manifold vacuum is used as an input signal to the transmission. The vacuum modulator receives vacuum signal from the engine. The vacuum modulator will increase line pressure to stiffen transmission shifting based during heavy engine loads. The increased line pressure will cause clutches and bands to hold tighter and help to diminish slipping.Most vehicles today are equipped with automatic transmissions that use electronic shift controls. The operation of the electronically controlled transmission is similar in principle to the non electric transmission. However, the electronically shifted transmission uses input signals from the vehicle control module to control shift points, rather than a governor and throttle valve. The vehicle control module controls transmission shifting based on engine and transmission data sensors. The throttle position sensor is used in place of the mechanical throttle valve. The vehicle speed sensor is used to replace the governor. Engine load sensors, such as a manifold pressure sensor, are used to control shift feel. A vacuum modulator may still be used by some vehicle makes to assist in shift control. The vehicle control module will utilize this information to operate various shift control solenoids inside the transmission. These shift control solenoids in turn control line pressure to theirrespective shift control valves that in turn apply or release pressure to bands or clutches.The result of using electronic shift controls is an automatic transmission that operates more efficiently to tailor shifting to meet engine demands. Fuel economy and vehicle emission control are enhanced by more precise control of the automatic transmission. Vehicle control modules have the ability to adapt transmission shifting to meet the individual driving patterns of the vehicle. Also internal overheat protection is provided for by the control module’s ability to monitor transmission fluid temperature and change transmission shifting and operation to minimize temperature related damage. On many vehicles, the EEC (Electronic Engine Control) will “learn” a particular driver’s driving style. This information is stored in the EEC’s memory. If the battery is disconnected (during replacement, for example), the vehicle may shift erratically for a short time until the EEC re-learns the driver’s driving style and then reprograms itself. This is important to remember and a little patience can save you a trip to the auto repair shop, ie. after your battery is replaced, drive your vehicle for a day or so and see if the erratic shifting issue is resolved (most likely it will correct itself).The automatic transaxle is an automatic transmission that also contains the final drive for delivering power to the driving wheels. Operation is comparable to the operation of the conventional automatic transmission. With the exception of a differential and axle shafts located in the lower portion of the transaxle. The automatic transaxle is used almost exclusively in front wheel drive vehicles..自动变速器与驱动桥概述自动变速器是高度复杂的精密设备。

驱动桥汽车外文文献翻译、中英文翻译、外文翻译

驱动桥汽车外文文献翻译、中英文翻译、外文翻译

驱动桥汽车外文文献翻译、中英文翻译、外文翻译The driving axle is an essential component of a ___。

It consists of several parts。

including a housing。

axle drive。

differential。

two axle shafts。

and final drives if necessary.The main purpose of the axle drive is to ___。

___.There are two types of axle drives: single and double-stage。

The single-stage type has a pair of gears。

while the double-stage type has two pairs of gears。

The drive ___ case。

To ce noise during n。

axle drive ___.In summary。

___。

It includes several components that work ___ to the wheels。

The axle drive shaft is an essential part of the axle drive。

and there are two types of axle drives。

To ce noise during n。

the driving gears are made with ___.When a car turns。

___ a greater distance than the inner ___。

thanks to the differential ns ___ around the slower side gear。

the inner ___。

汽车驱动桥设计外文文献翻译、中英文翻译、外文翻译

汽车驱动桥设计外文文献翻译、中英文翻译、外文翻译

AppendixChina in the first half of 2008 about 93 million trucks accumulative total sales of cars, vans 61 million vehicles, year-on-year growth of 20.2%, visible light car in commercial car production has a large proportion. And driving axle is very important in the vehicle driving axle is the important car auto bearing assembly, auto frame and integral by suspension of body vertical force, to lead the longitudinal forces, transverse force and torque, and impact load; Driving axle also delivers the transmission, the maximum torque reaction is under.Automobile driving axle structure and design parameters in addition to the reliability of the automobile and durability have important influence on the outside, also for the automobile driving performance such as power, economy, smooth, through sex, mobility Automobile driving axle design involves the mechanical parts and components is widely to these varieties, spare parts, components and assemblies manufacturing also almost want to design to all modern machinery manufacturing process, design a simple structure, reliable operation and low cost, can greatly reduce the drive axle of the total cost of the vehicle production, promote economic development, and car to drive through the car studying and designing practice, can better learning and mastery of the modern car design and mechanical design of the comprehensive knowledge and skills, and the overall thinking and operation skill check, drawing, is the very important link, so ontology of a structure design of fine vans axles has certain Automobile driving axle is one of the main parts car, its basic function is to enlarge the shaft or by the torque transmission spread, then torque distribution to drive wheels, and make about driving wheel has about vehicle movement required differential function; Axles in the end of powertrain system, choose proper Lord slowdown, ensure cars than with sufficient ground clearance is achieved, gear and other transmission job need to ensure smooth are the parameters, and even bear effect on the pavement drive axle and frame or carrying body vertical force, the lead between transverse and longitudinal force and torque force. Driving axle quality, performance will have a direct impact on the vehicle's safety, economy, comfort and reliability. After the car driving axle design can make the students' comprehensive by using their This thesis research aims to overall matching car by driving axle Lord finish design of gear reducer, differential component such as type of design and calculation, and complete checking and comprehensive design single main reducer, then the batch Through the design of the vehicle driving axle should also master the understanding, including each component interaction between the body and the electricalsystem, the influence and cooperate to drive axle of the process and therefore more familiar with vehicle mastery. That in the future the production and living effectly use.附录我国2008年上半年货车累计销售约93万辆,其中轻型货车61万辆,同比增长20.2%,可见轻型汽车在商用汽车生产中占有很大的比重。

驱动桥5000字外文翻译文献

驱动桥5000字外文翻译文献

As the bearing cage rotates, read the value7. indicated on the scale.Preload normally is specified as torque re-8. quired to rotate the pinion bearing cage, so take a reading only when the cage is rotating. Starting torque will give a false reading.To calculate the preload torque, measure the 9. diameter of the bearing cage where the cord was wound. Divide this dimension in half to get the radius.10. U se the following procedure to calculate thebearing preload torque:Standard.Pull (lb) 3 radius (inches) 5 preload (lb-in.)orPreload (lb-in.) 3 0.113 (a conversion constant) 5 preload (N .m)Install the yoke, flat washer, and nut. Tighten 6. the nut snugly. Tap the end of the input shaft lightly to seat the bearings.Measure the input shaft endplay again with 7. the dial indicator. If endplay is still incorrect, repeat steps 3 through 7.With the endplay correct, seal the shim pack 8. to prevent lube leakage. Then torque the i nput shaft nut and cover capscrews to the correct value.24.5 A XLE ADJUSTMENTSAND CHECKSThis section introduces the differential carrier adjust-ments, checks, and tests that the truck technician must be capable of performing; some have beenr eferred to previously in the text. For the most part, the procedures described here are general in nature. The truck technician should refer to OEM servicel iterature for specific procedures.PINION BEARING PRELOADMost differential carriers are provided with a press-fit outer bearing on the drive pinion gear. Some older rear drive axles use an outer bearing, which slips over the drive pinion. The procedures for adjusting both types follow.Press-Fit Method AdjustmentTo adjust the pinion bearing preload using the press-fit method, use the following procedure:Assemble the pinion bearing cage, bearings, 1. spacer, and spacer washer (without drive pin-ion or oil seal). Center the bearing spacer and spacer washer between the two bearing cones (Figure 24–49).When a new gear set or pinion bearings are 2. used, select a nominal size spacer based on OEM specifications. If original parts are used, use a spacer removed during disassembly of the drive.Place the drive pinion and cage assembly in a 3. press, with the gear teeth toward the bottom.Apply and hold the press load to the pinion 4. bearing. As pressure is applied, rotate the bearing cage several times so that the bear-ings make normal contact.While pressure is held against the assembly, wind 5. a cord around the bearing cage several times.Attach a spring scale to the end of the cord 6. (Figure 24–50). Pull the cord with the scale ona horizontal line.FIGURE 24–49 Assembly of the pinion bearing cage.(Courtesy of Dana Corporation)FIGURE 24–50 Cage in press to check bearingp reload.Sleeve must applymust be against the outer bearing. If the fit between the yoke or flange splines and drive pinion splines is tight, use a press to install the yoke or flange (Figure 24–51).Temporarily install the drive pinion and cage 4. assembly in the carrier (Figure 24–52). Do not install shims under the bearing cage.Install the bearing cage to the carrier cap-5. screws. Washers are not required at this time. Hand-tighten the capscrews.Fasten a yoke or flange bar to the yoke or 6. flange (Figure 24–53). The bar will hold the drive pinion in position when the nut ist ightened.Metric.Pull (kg) 3 radius (cm) 5 preload (kg-cm) orPreload (kg-cm) 3 0.098 (a conversion constant) 5 preload (N .m)Examples. We can convert the foregoing equa-tions into examples by applying some data to them:Standard7.5 lb 3 3.31 in. 5 24.8 lb-in. (preload) or24.8 lb-in. 3 0.113 5 2.8 N .m (preload)Metric3.4 kg 3 8.4 cm 5 28.6 kg-cm (preload) or28.6 kg-cm 3 0.098 5 2.8 N .m (preload)11. I f necessary, adjust the pinion bearing preloadby changing the pinion bearing spacer. A thicker spacer will decrease preload, whereas a thinner spacer will increase the preload.12. O nce the correct bearing preload has beenestablished, note the spacer size used. Select a spacer 0.001 inch (0.025 mm) larger for use in the final pinion bearing cage assembly pro-cedures. The larger spacer compensates for slight expansion of the bearing, which occurs when pressed on the pinion shank. The trial spacer pack should result in correct pinion bearing preload in three times out of four cases.Y oke Method of AdjustmentTo adjust the pinion bearing preload using the yoke or flange method, proceed as follows:Assemble the complete pinion bearing cage 1. as recommended in the press-fit method.A forward axle pinion is equipped with a heli-2. cal gear. For easier disassembly during bear-ing adjustment procedures, use a dummy yoke (if available) in place of the helical gear.Install the input yoke or flange, nut, and 3.washer on the drive pinion. The yoke or flangeFIGURE 24–51 Using a press to install the yoke orflange to the drive pinion. (Courtesy of Arvin Meritor)FIGURE 24–52 Install the pinion and cage assembly in the carrier housing. (Courtesy of Arvin Meritor)indicated on the torque wrench (see Figure 24–55). Typical value is 50 lb-ft. (68 N .m)m aximum applied to one side gear.If the torque value exceeds the specification, 5. disassemble the differential gears from the case halves.Check the case halves, spider, gears, and 6. thrust washers for the problem that caused the torque value to exceed specifications. Re-pair or replace defective parts as required. Remove any foreign debris.Check/Adjust Pinion Cage Shim PackThis procedure is used to check and adjust the thick-ness of the shim pack used in the pinion bearing cage. Use this procedure if a new drive pinion and crownTighten the nut on the drive pinion to specifi-7. cation, typically 400 to 700 lb-ft. (542 to 950 N .m).Remove the yoke or flange bar.8. Attach a torque wrench to the drive pinion 9. nut. Rotate the drive pinion and read the value indicated on the torque wrench. Preload is correct when the torque required to rotate the pinion bearing cage is from 15 to 35 lb-in. (1.7 to 4.0 N .m).To adjust the pinion bearing preload, disas-10. semble the pinion bearing cage and change the pinion bearing spacer size. A thicker spacer will decrease preload, whereas a thin-ner spacer will increase preload.Differential Rolling ResistanceA check to measure and establish differential rolling resistance follows. To perform this check, a special tool must be made. You can easily make this tool from an old axle shaft that matches the spline size of the differential side gear. Figure 24–54 illustrates the fab-rication specifications for this special tool.To check differential resistance to rotation, use the following procedure:Install soft metal covers over the vise jaws to 1. protect the ring gear (Figure 24–55).Place the differential and crown gear assem-2. bly in the vise.Install the special tool into the differential until 3. the splines of the tool and one side gear are engaged.Attach a torque wrench to the nut of the spe-4. cial tool and rotate the differential gears. As the differential gears rotate, read the valueFIGURE 24–55 Reading the torque value to check the rolling resistance. (Courtesy of Arvin Meritor)FIGURE 24–53 Using a flange bar to hold the drivepinion in position. (Courtesy of Arvin Meritor)FIGURE 24–54 Fabrication details for a tool to checkthe rolling resistance. (Courtesy of Arvin Meritor)If the new pinion cone number is a minus (–), sub-8. tract the number from the standard shim packthickness that was calculated in step 3 or 4.The value calculated in step 7 or 8 is the 9.t hickness of the new shim pack that will bei nstalled. Figure 24–59 illustrates several e xamples of determining shim pack t hickness.Install the drive pinion, bearing cage, and new10. shim pack into the differential carrier.gear set is to be installed, or if the depth of the drive pinion has to be adjusted. You are checking the rolling resistance using a torque wrench.To check/adjust the shim pack thickness (Figure 24–56), do the following:With a micrometer, measure the thickness of 1. the old shim pack removed from under the pinion cage (Figure 24–57). Record the mea-surement for later use.Look at the pinion cone (PC) variation number 2. on the drive pinion being replaced (Figure 24–58). Record this number for later use also.If the old pinion cone number is a plus (+), 3. subtract the number from the old shim pack thickness that was recorded in step 1.If the old pinion cone number is a minus (–), 4. add the number to the old shim thickness that was measured in step 1.The value calculated in step 3 or 4 is the 5.t hickness of the standard shim pack without variation.Look at the PC variation number on the new 6. drive pinion that will be installed. Record the number for later use.If the new pinion cone number is a plus (+), 7. add the number to the standard shim packthickness that was calculated in step 3 or 4.FIGURE 24–56 Drive pinion depth controlled by shimpack thickness. (Courtesy of Arvin Meritor)FIGURE 24–57 Measuring the thickness of the old shim pack. Mike each shim individually then add tocalculate total thickness. (Courtesy of Arvin Meritor)FIGURE 24–58 Location of the pinion cone (PC)v ariation number. (Courtesy of Arvin Meritor)Adjust Differential Bearing PreloadOne of two methods can be used to check and adjust the preload of the differential bearings.Method One.Attach a dial indicator onto the mounting 1. flange of the carrier and adjust the indicator so that the plunger rides on the back surface of the crown ring gear (Figure 24–60).Loosen the bearing adjusting ring that is op-2. posite the ring gear so that a small amount of endplay is indicated on the dial indicator. To turn the adjusting rings, use a T-bar wrench that engages two or more opposite notches in the ring (Figure 24–61).Move the differential and crown gear to the 3. left and right using prybars as you read the dial indicator. Use two prybars that fit be-tween the bearing adjusting rings and the ends of the differential case (Figure 24–62). You also can use two prybars between the differential case or crown gear and the carrier at locations other than those just described. In either case, the prybars must not touch the differential bearings.EXAMPLES:Inchesmm 1.Old Shim Pack Thickness Old PC Number, PC +2Standard Shim Pack Thickness New PC Number, PC +5New Shim Pack Thickness .030.76–.002–.05.028.71+.005+.13.033.842.Old Shim Pack Thickness Old PC Number, PC –2Standard Shim Pack Thickness New PC Number, PC +5New Shim Pack Thickness .030.76+.002+.05.032.81+.005+.13.037.943.Old Shim Pack Thickness Old PC Number, PC +2Standard Shim Pack Thickness New PC Number, PC –5New Shim Pack Thickness .030.76–.002–.05.028.71–.005–.13.023.584.Old Shim Pack Thickness Old PC Number, PC –2Standard Shim Pack Thickness New PC Number, PC –5New Shim Pack Thickness.030.76+.002+.05.032.81–.005–.13.027.68FIGURE 24–59 Determining shim pack thickness.(Courtesy of ArvinMeritor Inc.)FIGURE 24–60 Dial indicator attached to carrier-mounted flange. (Courtesy of Arvin Meritor)FIGURE 24–61 Turning the adjusting ring using aT-bar wrench. (Courtesy of Arvin Meritor)FIGURE 24–62 Using pry bars to adjust play in the crown gear. (Courtesy of Arvin Meritor)Tighten the same bearing adjusting ring4.so that no endplay shows on the diali ndicator.Move the differential and crown gear to the5.left and right as needed. Repeat step 3 untilzero endplay is achieved.Tighten each bearing adjusting ring one6.notch from the zero endplay measured instep 4.Method Two.A second method of checking pre-load is to measure the expansion between the bearing caps after you tighten the adjusting rings. Use the following procedure:Turn both adjusting rings hand tight against1.the differential bearings.Measure the distance X or Y between oppo-2.site surfaces of the bearing caps (Figure24–63A) using a large micrometer of thec orrect size (Figure 24–63B). Make a note ofthe m easurement.Tighten each bearing adjusting ring one3.notch.Measure the distance X or Y again. Compare4.the dimension with the distance X or Y mea-sured in step 2. The difference between thetwo dimensions is the amount that the bear-ing caps have expanded.Example: Measurements of a carrier.Distance X or Y before tightening adjusting rings5 15.315 inches (389.00 mm)Distance X or Y after tightening adjusting rings5 15.324 inches (389.23 mm)15.324 inches minus 15.315 inches5 0.009 inch (0.23 mm) differenceIf the dimension is less than specification, repeat steps 3 and 4 as needed.Crown Gear Runout CheckTo check the runout of the crown/ring gear, do the f ollowing:Attach a dial indicator on the mounting flange1.of the differential carrier (Figure 24–64).Adjust the dial indicator so that the plunger or2.pointer is against the back surface of thecrown gear.FIGURE 24–63 (A) Location of distances measured to check expansion between bearing caps aftert ightening adjusting rings; (B) measuring this distance.(Courtesy of Arvin Meritor)FIGURE 24–64 Checking crown gear runout. (Courtesy of Arvin Meritor)Pinion and Crown Tooth ContactA djustment Correct tooth contact between the pinion and crown gear cannot be overemphasized, because improper tooth contact results in noisy operation and prema-ture failure. The tooth contact pattern consists of the lengthwise bearing (along the tooth of the ring gear) and the profile bearing (up and down the tooth). F igure 24–68 shows crown gear toothn omenclature.Adjust the dial of the indicator to zero.3. Rotate the differential and crown gear when4. reading the dial indicator. The runout of the crown gear must not exceed 0.008 inch (2 mm) (a typical value; refer to the applicable OEM service literature for the specificv alues).If runout of the crown gear exceeds the speci-5. fication, remove the differential and crown gear assembly from the carrier. Check the dif-ferential components, including the carrier, for the problem causing the runout of the gear to exceed specification. Repair or replace defec-tive components.After the components are repaired or re-6. placed, install the differential and crown gear into the carrier.Repeat the preload adjustment of the 7. differential bearings. Then repeat this runout procedure.Check/Adjust Crown Gear BacklashIf the used crown and pinion gear set is installed, ad-just the backlash to the setting that was measured before the carrier was disassembled. If a new gear set is to be installed, adjust backlash to the correct speci-fication for the new gear set.To check and adjust ring gear backlash, do thef ollowing: Attach a dial indicator onto the mounting1. flange of the carrier (see Figure 24–64).Adjust the dial indicator so that the plunger is 2. against the tooth surface at a right angle.Adjust the dial of the indicator to zero, making 3. sure that the plunger is loaded through at least one revolution.Hold the drive pinion in position.4. When reading the dial indicator, rotate the5. crown gear a small amount in both directions against the teeth of the drive pinion (Figure 24–65). If the backlash reading is not within specification (typically ranging from 0.010 to 0.020 inch or 254 to 508 mm), adjust backlash as outlined in steps 6 and 7.Loosen one bearing adjusting ring one notch 6. and then tighten the opposite ring the same amount. Backlash is increased by moving the crown gear away from the drive pinion (Figure 24–66). Backlash is decreased by moving the crown gear toward the drive pin-ion (Figure 24–67).Repeat steps 2 through 5 until the backlash is 7.within specifications.FIGURE 24–65 Check crown gear backlash. ( Courtesy of Arvin Meritor)FIGURE 24–66 Adjustments to increase backlash. (Courtesy of Arvin Meritor)the pattern in an unloaded condition (such as when you are performing this test) will be approximately one-half to two-thirds of the crown gear tooth in most models and ratios.Checking Tooth Contact Pattern on a Used Gear Set. Used gearing will not usually display the square, even contact pattern found in new gear sets. The gear will normally have a pocket at the toe-end of the gear tooth (Figure 24–71) that tails into a contact line along the root of the tooth. The more use a gear has had, the more the line becomes the dominant characteristic of the pattern.Adjusting Tooth Contact Pattern. When dis-assembling, make a drawing of the gear tooth con-tact pattern so that when reassembling it is possible to replicate approximately the same pattern. A cor-rect pattern should be clear of the toe and centers evenly along the face width between the top land and the root. Otherwise, the length and shape of the pattern can be highly variable and are usually con-sidered acceptable—providing the pattern does not run off the tooth at any time. If necessary, adjust the contact pattern by moving the crown gear and drive pinion.Checking Tooth Contact Pattern on a New Gear Set. Paint 12 crown gear teeth with a marking compound (Figure 24–69) and roll the gear to obtain a tooth contact pattern. A correct pattern should be well centered on the crown gear teeth with lengthwise contact clear of the toe (Figure 24–70). The length ofFIGURE 24–67 Adjustments to decrease backlash.(Courtesy of Arvin Meritor)FIGURE 24–68 Crown gear tooth nomenclature.(Courtesy of Dana Corporation)FIGURE 24–69 Application of a marking compoundto check tooth contact. (Courtesy of Dana Corporation)FIGURE 24–70 Correct tooth contact patternfor new gearing. (Courtesy of Dana Corporation)FIGURE 24–71 Correct tooth contact pattern for used gearing. (Courtesy of Dana Corporation)making adjustments, first adjust the pinion and then the backlash. Continue this sequence until the pattern is satisfactory.Thrust Screw AdjustmentFor those differential carriers equipped with a thrust screw, perform the following procedure. (If the carrier assembly does not have a thrust block, proceed to step 4 of this procedure.)Rotate the carrier in the repair stand until the 1. back surface of the crown gear is toward the top.Put the thrust block on the back surface of 2. the ring gear. The thrust block must be in the center between the outer diameter of the gear and the differential case.Rotate the crown gear until the thrust block 3. and hole for the thrust screw, in the carrier, are aligned.Install the jam nut on the thrust screw, one-4. half the distance between both ends (Figure 24–74).Install the thrust screw into the carrier until the 5. screw stops against the crown gear or thrust block.Loosen the thrust screw one-half turn, or 180 6. degrees.Tighten the jam nut to the correct torque value 7. against the carrier (typical values range from 150 to 295 lb-ft. or 200 to 400 N .m) (Figure 24–75).Axle TrackingAxle tracking can be measured using the older tram bar method or electronic alignment equipment. The procedures for setting axle alignment and tracking areexplained in Chapter 25.FIGURE 24–72 Two incorrect patterns when adjusting pinion position. (Courtesy of Dana Corporation)Crown gear position controls the backlash setting. This adjustment also moves the contact pattern along the face width of the gear tooth (Figure 24–72). Pinion position is determined by the size of the pinion bear-ing cage shim pack. It controls contact on the tooth depth of the gear tooth (Figure 24–73).These adjustments are interrelated. As a result, they must be considered together even though thepattern is altered by two distinct operations. WhenFIGURE 24–73 Two incorrect patterns when adjusting backlash. (Courtesy of Dana Corporation)• Most differential carriers are replaced as rebuilt/exchange units, so the role of the technician is, more often than not, to diagnose the problem and then, if necessary, to replace the defective assembly as a unit.• The technician who has disassembled and reas-sembled differential carriers should find trouble-shooting procedures easier to follow.• Follow the OEM procedure when disassem-bling differential carriers. Taking a few mo-ments to measure shim packs and gear tooth contact patterns on disassembly can save considerable time when reassembling thec arrier.• A crown and pinion gear set often can ber eused when rebuilding a differential carrier. Make sure that you inspect it properly ond isassembly.• Crown and pinion gear sets are always replaced as a matched pair during a rebuild.• When setting crown and pinion backlash, it is increased by moving the crown gear away from the drive pinion and decreased by moving the crown gear toward the drive pinion.• Adhering to OEM-recommended lubrication schedules is the key to ensuring the longest service life from both drive and dead axles.• Knowing the correct procedure to check lubricant level is essential. The level is correct when lubri-cant is exactly level with the bottom of the fill hole.• Because most OEMs approve of the use of syn-thetic lubricants in final drive carriers, lubrication drain schedules have been greatly increased in recent years. Drain schedules are determined by the actual lubricant used and the type of appli-cation to which the vehicle is subjected.• Servicing of axles on heavy-duty trucks consists of routine inspection, lubrication, cleaning, and, when required, troubleshooting and component overhaul.• Failure analysis is required to prevent recurrent failures.• Drive axle carrier components usually fail for one of the following reasons: Shock load Fatigue Spinout Lubrication problemsNormal wearFIGURE 24–74 Installing the jam nut on the thrust screw. (Courtesy of Arvin Meritor)FIGURE 24–75 Tighten the jam nut to the correct torque value. (Courtesy of Arvin Meritor)SUMMARY。

汽车驱动桥设计外文文献翻译、中英文翻译、外文翻译

汽车驱动桥设计外文文献翻译、中英文翻译、外文翻译

AppendixChina in the first half of 2008 about 93 million trucks accumulative total sales of cars, vans 61 million vehicles, year-on-year growth of 20.2%, visible light car in commercial car production has a large proportion. And driving axle is very important in the vehicle driving axle is the important car auto bearing assembly, auto frame and integral by suspension of body vertical force, to lead the longitudinal forces, transverse force and torque, and impact load; Driving axle also delivers the transmission, the maximum torque reaction is under.Automobile driving axle structure and design parameters in addition to the reliability of the automobile and durability have important influence on the outside, also for the automobile driving performance such as power, economy, smooth, through sex, mobility Automobile driving axle design involves the mechanical parts and components is widely to these varieties, spare parts, components and assemblies manufacturing also almost want to design to all modern machinery manufacturing process, design a simple structure, reliable operation and low cost, can greatly reduce the drive axle of the total cost of the vehicle production, promote economic development, and car to drive through the car studying and designing practice, can better learning and mastery of the modern car design and mechanical design of the comprehensive knowledge and skills, and the overall thinking and operation skill check, drawing, is the very important link, so ontology of a structure design of fine vans axles has certain Automobile driving axle is one of the main parts car, its basic function is to enlarge the shaft or by the torque transmission spread, then torque distribution to drive wheels, and make about driving wheel has about vehicle movement required differential function; Axles in the end of powertrain system, choose proper Lord slowdown, ensure cars than with sufficient ground clearance is achieved, gear and other transmission job need to ensure smooth are the parameters, and even bear effect on the pavement drive axle and frame or carrying body vertical force, the lead between transverse and longitudinal force and torque force. Driving axle quality, performance will have a direct impact on the vehicle's safety, economy, comfort and reliability. After the car driving axle design can make the students' comprehensive by using their This thesis research aims to overall matching car by driving axle Lord finish design of gear reducer, differential component such as type of design and calculation, and complete checking and comprehensive design single main reducer, then the batch Through the design of the vehicle driving axle should also master the understanding, including each component interaction between the body and the electricalsystem, the influence and cooperate to drive axle of the process and therefore more familiar with vehicle mastery. That in the future the production and living effectly use.附录我国2008年上半年货车累计销售约93万辆,其中轻型货车61万辆,同比增长20.2%,可见轻型汽车在商用汽车生产中占有很大的比重。

中英文文献翻译—驱动桥和差速器

中英文文献翻译—驱动桥和差速器

附录A 英文文献Drive axle/differentialAll vehicles have some type of drive axle/differential assembly incorporated into the driveline. Whether it is front, rear or four wheel drive, differentials are necessary for the smooth application of engine power to the road.PowerflowThe drive axle must transmit power through a 90°angle. The flow of power in conventional front engine/rear wheel drive vehicles moves from the engine to the drive axle in approximately a straight line. However, at the drive axle, the power must be turned at right angles (from the line of the driveshaft) and directed to the drive wheels.This is accomplished by a pinion drive gear, which turns a circular ring gear. The ring gear is attached to a differential housing, containing a set of smaller gears that are splined to the inner end of each axle shaft. As the housing is rotated, the internal differential gears turn the axle shafts, which are also attached to the drive wheels.Fig 1 Drive axleRear-wheel driveRear-wheel-drive vehicles are mostly trucks, very large sedans and many sports car and coupe models. The typical rear wheel drive vehicle uses a front mounted engine and transmission assemblies with a driveshaft coupling the transmission to the rear drive axle. Drive in through the layout of the bridge, the bridge drive shaft arranged vertically in the same vertical plane, and not the drive axle shaft, respectively, in their own sub-actuator with a direct connection, but the actuator is located at the front or the back of the adjacent shaft of the two bridges is arranged in series. Vehicle before and after the two ends of the driving force of the drive axle, is the sub-actuator and the transmission through the middle of the bridge. The advantage is not only a reduction of the number of drive shaft, and raise the driving axle of the common parts of each other, and to simplify the structure, reduces the volume and quality.Fig 2 Rear-wheel-drive axleSome vehicles do not follow this typical example. Such as the older Porsche or Volkswagen vehicles which were rear engine, rear drive. These vehicles use a rear mounted transaxle with halfshafts connected to the drive wheels. Also, some vehicles were produced with a front engine, rear transaxle setup with a driveshaft connecting the engine to the transaxle, and halfshafts linking the transaxle to the drive wheels.Differential operationIn order to remove the wheel around in the kinematics due to the lack of co-ordination about the wheel diameter arising from a different or the same rolling radius of wheel travel required, inter-wheel motor vehicles are equipped with about differential, the latter to ensure that the car driver Bridge on both sides of the wheel when in range with a trip to the characteristics of rotating at different speeds to meet the requirements of the vehicle kinematics.Fig 3 Principle of differentialThe accompanying illustration has been provided to help understand how this occurs.1.The drive pinion, which is turned by the driveshaft, turns the ring gear.2.The ring gear, which is attached to the differential case, turns the case.3.The pinion shaft, located in a bore in the differential case, is at right angles to the axle shafts and turns with the case.4.The differential pinion (drive) gears are mounted on the pinion shaft and rotate with the shaft .5.Differential side gears (driven gears) are meshed with the pinion gears and turn with the differential housing and ring gear as a unit.6.The side gears are splined to the inner ends of the axle shafts and rotate the shafts as the housing turns.7.When both wheels have equal traction, the pinion gears do not rotate on the pinion shaft, since the input force of the pinion gears is divided equally between the two side gears.8.When it is necessary to turn a corner, the differential gearing becomes effective and allows the axle shafts to rotate at different speeds .Open-wheel differential on each general use the same amount of torque. To determine the size of the wheel torque to bear two factors: equipment and friction. In dry conditions, when a lot of friction, the wheel bearing torque by engine size and gear restrictions are hours in the friction (such as driving on ice), is restricted to a maximum torque, so that vehicles will not spin round. So even if the car can produce more torque, but also need to have sufficient traction to transfer torque to the ground. If you increase the throttle after the wheels slip, it will only make the wheels spin faster.Fig 4 Conventional differentialLimited-slip and locking differential operationFig 5 Limited-slip differentialDifferential settlement of a car in the uneven road surface and steering wheel-driven speedat about the different requirements; but is followed by the existence of differential in the side car wheel skid can not be effective when the power transmission, that is, the wheel slip can not produce the driving force, rather than spin the wheel and does not have enough torque. Good non-slip differential settlement of the car wheels skid on the side of the power transmission when the issue, that is, locking differential, so that no longer serve a useful differential right and left sides of the wheel can be the same torque.Limited-slip and locking differential operation can be divided into two major categories:(1) mandatory locking type in ordinary differential locking enforcement agencies to increase, when the side of the wheel skid occurs, the driver can be electric, pneumatic or mechanical means to manipulate the locking body meshing sets of DIP Shell will be with the axle differential lock into one, thus the temporary loss of differential role. Relatively simple structure in this way, but it must be operated by the driver, and good roads to stop locking and restore the role of differential.(2) self-locking differential installed in the oil viscosity or friction clutch coupling, when the side of the wheel skid occurs when both sides of the axle speed difference there, coupling or clutch friction resistance on the automatic, to make certain the other side of the wheel drive torque and the car continued to travel. When there is no speed difference on both sides of the wheel, the frictional resistance disappeared, the role of automatic restoration of differentials. More complicated structure in this way, but do not require drivers to operate. Has been increasingly applied in the car. About non-slip differential, not only used for the differential between the wheels, but also for all-wheel drive vehicle inter-axle differential/.Gear ratioThe drive axle of a vehicle is said to have a certain axle ratio. This number (usually a whole number and a decimal fraction) is actually a comparison of the number of gear teeth on the ring gear and the pinion gear. For example, a 4.11 rear means that theoretically, there are 4.11 teeth on the ring gear for each tooth on the pinion gear or, put another way, the driveshaft must turn 4.11 times to turn the wheels once. The role of the final drive is to reduce the speed from the drive shaft, thereby increasing the torque. Lord of the reduction ratio reducer, a driving force for car performance and fuel economy have a greater impact. In general, the more reduction ratio the greater the acceleration and climbing ability, and relatively poor fuel economy. However, if it is too large, it can not play the full power of the engine to achieve the proper speed. The main reduction ratio is more Smaller ,the speed is higher, fuel economy is better, but the acceleration and climbing ability will be poor.附录B 文献翻译驱动桥和差速器所有的汽车都装有不同类型的驱动桥和差速器来驱动汽车行驶。

汽车驱动桥常见故障分析及维修方法外文文献翻译、中英文翻译、外文翻译

汽车驱动桥常见故障分析及维修方法外文文献翻译、中英文翻译、外文翻译

汽车驱动桥常见故障分析及维修方法外文文献翻译、中英文翻译、外文翻译附录Car driver bridge just common failure analysis and repair methods Motor reducer main function is to increase the input torque, lower speed, and will accept the transfer of power to change the direction of differential. Disassembly in the maintenance process, the main reducer assembly and adjustment of the quality of the good or bad, a direct impact on the main reducer of the state of technology and the main gear reducer, vice life. Must be in accordance with technical requirements and methods to ensure that the assembly quality and accuracy of the adjustment. Reducer in the main assembly in the process of adjustment, including the main owners, driven bevel gear bearing pre-adjustments, the main, driven cone-prints and meshing gears meshing space adjustments, and so on. Reducer in the main assembly adjustment, the adjustment in order to ensure the quality of assembly, must abide by the rules as follows: First, the first adjustment of the pre-bearings, and then adjust the gear mesh, vice-prints, the final adjustment of the meshing gears, deputy space. Secondly, the main, driven gear bearing cone of pre-degree must be provided for in the original methods and numerical check and adjust the main reducer in the process of adjustment, bearing the pre-degree change may not always be in line with the original Provides value. Third, to ensure the engagement of qualified prints on the premise of the adjustment of meshing gears, deputy space. Meshing and mesh-prints of the changes in the amount of space must be in compliance with technical requirements, otherwise it is necessaryto replace the pair in pairs. Fourth, the adjustment process, such as bevel gear, bevel gear Aoli Kang and hypoid bevel gear, often moving to take the initiative to adjust the bevel gear mesh prints, driven by mobile bevel gear meshing space adjustments. The high-arc bevel gear Gleason bevel gear meshing and mesh-prints of the gap adjustment method is not special.Bearing reducer main pre-adjustments in order to remove the main, driven bevel gear shaft bearing the extra space axial and radial clearance, and reducer installed in the main, driven bevel gear shaft bearings, it should be a certain The pre-compression, and part of the balance before and after the axial load bearing. This willmake the main, driven bevel gear at work to maintain the right mesh, and can pre-and post-bearings to obtain a more uniform wear. First of all, take the initiative to adjust the bevel gear bearing the pre-, pre-adjustment of their degrees in two ways: The first method is through changes in the gasket to adjust to adjust. Adjust the location of gaskets, and some separation between the two sets of bearings, some shaft in the shoulder, some in the back of the main reducer. Adjusted increase in the pads, reducing the pre-degree; pads to reduce the adjustment, increased pre-degrees. The second method is to use an alternate set of flexibility to adjust it by the installation, according to the provisions of torque tightening nut penetration margin of the fixed disk, so that every other set of elastic deformation resulting from the initiative to ensure the bevel gear bearing the pre-degrees. Next, adjust the bevel gear follower of the pre-degree bearing. According to the driver of the bridge structure is divided into two different ways: the first is a single-stage reducer, which is driven bevel gear differential bearing bearings, drivenadjustment bevel gear bearing pre-degree differential bearing adjustment is pre - Tight, adjust the differential bearing on both sides of the nut adjustment to achieve. Adjustments on both sides of the nut tightened, pre-degree increase; on both sides of the adjustment screw pine nut, pre-degree decrease. The second is a two-stage reducer, the bevel gear driven secondary and take the initiative to slow down the cylindrical gear with a fixed axis, with both ends of the bearing shell on the main reducer. Adjust the location of gaskets in the two bearings between the shell and cover. Adjusted increase in the pads, reducing the pre-degree; pads to reduce the adjustment, increased pre-degrees. Second, the main, driven bevel gears meshing tooth prints and the adjustment of the main side of the gap, driven bevel gears meshing side of the gap-tooth-prints and adjustment: the main, be driven bevel gear teeth along the direction of the long exposure, and its location in the control gear The little-central bias, the small end-to-end from the Ministry of 2 ~ 7mm, traces of contact with the length of not less than 50% of the long teeth, tooth direction of the high-contact-prints should be not less than 50% of the high-gear, the general should be from the addendum 0 . 80 ~ 1.60mm; side of the tooth gap to 0. 15 ~ 0. 50mm, but each of the bevel gears meshingVice change in the amount of space no larger than 0.15mm. When the owners, driven bevel gears meshing side of the gap-tooth-prints and do not meet the requirements should be adjusted in accordance with the following method to simplify the formula is: "Progressive", that is, when the mating preference-prints big-time, move from gear to gear shift Near; at this time if the tooth side of the gap is too small, will take the initiative to move out of gear. "From a small", that is, when the matingpreference-prints little-time, move from gear to gear the initiative away; at this time if the tooth side of the gap is too large, the initiative will be moved closer to the gear inside. "Lord jacking", that is, when the mating preference-prints addendum, the initiative will be moved closer to the driven gear to gear; at this time if the tooth side of the gap is too small, will be driven out of gear away. "The main root out", that is, when the mating preference-prints root, it will take the initiative to gear since moving away gear; at this time if the tooth side of the gap is too large, driven gear will be moved closer to the inside.In the motor-driven mechanical automotive power train, drive power train bridge at the end of their basic function is to increase the transmission shaft or transmission came directly from the torque, torque will be allocated to the left and right wheel drive with Vehicle kinematics required by the differential function; at the same time, drivers also have to face the role of the bridge on the road or inside the frame and between the vertical, horizontal and vertical force. Therefore, vehicle drive axle should have the following functions: to ensure that the right has a reduction ratio, so that the car has the best power and fuel economy; differential with the role to ensure that the vehicle or to the uneven roads, tires do not have a Waterloo is delayed; have greater ground clearance in order to ensure the adoption of good; as much as possible to reduce weight in order to reduce vehicle weight; gear transmission and other mechanical work in a smooth, noise-free. Driver function as the bridge complex, so a higher failure rate. Its main fault: the early damage to the main reducer, made bridge-driven sound, heating and oil and so on.Bridge driver were the causes of the different and various fault is not the formation of a single isolated, but interrelated. Ifafailure occurred in a timely manner is not ruled out, it is easy to induce another failure to form a chain reaction. If the gap is too small mesh gear, it would drive axle fever, and it will lead to fat drive axle ring, but also the main cause of early damage to the reducer. Reducer is the main driver bridge in the heart of its early damage will seriously affect the life of the drive axle. Early in the form of its damage are: Vice-gear early wear, tooth fracture, early damage to the gear bearings and so on. Meshing gears are too small or too large gap caused by wear and tear in the early gears. Bearing the pre-force is too large or too small. Preload is too large, the impact on the efficiency of transmission so that the bearings overheat and shorten the life span; Preload over an hour to make the situation worse meshing of gears, contact stress increases, leading to a pair of early wear and tear. Not add gear oil requirements. Main reducer to be added as required gear oil in order to guarantee the normal lubrication of the gear, otherwise, in a very short car mileage, the tooth will be due to poor lubrication caused by pitting, and a sharp bond wear. Driven gear as a result of the adjustment locking nut loose and have a shift. Adjust the nut loose, causing a passive gear shift, the meshing gap change gear, Deputy Ambassador of early wear and tear.Common faults:1. Tooth fracture. Meshing gears too much space. When the gear mesh in time to adjust without too much space, so that the owners, driven gear engagement in the process of impact, making gear fault.2. Differential gear bearings or bearing damage. Bearing damage, roller out in the main reducer, the gear will be damaged.3. Driven gear differential with the loose bolt connections, and off, also damaged gear.4. Severely overloaded vehicle, so that the bearing load, making it lower life expectancy. Overloaded vehicle traveling through uneven pavement, gears and bearings, etc. impact on the load in a row and the role of the early damage occurred.In short, the judge ruled out and drive axle failure, it is necessary to analyze specific issues. In general, improper use, improper assembly adjustment, the quality of the parts itself is a question which drives the root causes of bridge failure. The fault has produced a number of reasons, or one; at the same time, adjustmentof the assembly, such as using incompatible with a drive axle that could cause a variety of failures.汽车驱动桥常见故障分析及维修方法汽车主减速器的功用是将输入的转矩增大,转速降低,并将接受的动力传递方向改变后传给差速器。

汽车差速器中英文对照外文翻译文献

汽车差速器中英文对照外文翻译文献

中英文对照外文翻译(文档含英文原文和中文翻译)Failure analysis of an automobile differential pinion shaft AbstractDifferential is used to decrease the speed and to provide moment increase for transmitting the movement coming from the engine to the wheels by turning it according to the suitable angle in vehicles and to provide that inner and outer wheels turn differently. Pinion gear and shaft at the entrance are manufactured as a single part whereas they are in different forms according to automobile types. Mirror gear which will work with this gear should become familiar before the assembly. In case of any breakdown, they should be changed as a pair. Generally, in these systems there are wear damages in gears. The gear inspected in this study has damage as a form of shaft fracture.In this study, failure analysis of the differential pinion shaft is carried out. Mechanical characteristics of the material are obtained first. Then, the microstructure and chemical compositions are determined. Some fractographic studies are 2005 Elsevier Ltd. All rights reserved.Keywords: Differential; Fracture; Power transfer; Pinion shaft1. IntroductionThe final-drive gears may be directly or indirectly driven from the output gearing of the gearbox. Directly driven final drives are used when the engine and transmission units are combined together to form an integral construction. Indirectly driven final drives are used at the rear of the vehicle being either sprung and attached to the body structure or unsprung and incorporated in the rear-axle casing. The final-drive gears are used in the transmission system for the following reasons [1]:(a) to redirect the drive from the gearbox or propeller shaft through 90°and,(b) to provide a permanent gear reduction between the engine and the driving road-wheels.In vehicles, differential is the main part which transmits the movement coming from the engine to the wheels On a smooth road, the movement comes to both wheels evenly. The inner wheel should turn less and the outer wheel should turn more to do the turning without lateral slipping and being flung. Differential, which is generally placed in the middle part of the rear bridge, consists of pinion gear, mirror gear, differential box, two axle gear and two pinion spider gears.A schematic illustration of a differential is given in Fig, 1. The technical drawing of pinion the fractured pinion shaft is also given in Fig, 2, Fig. 3 shows the photograph of the fractured pinion shaft and the fracture section is indicated.In differentials, mirror and pinion gear are made to get used to each other during manufacturing and the same serial number is given. Both of them are changed on condition that there are any problems. In these systems, the common damage is the wear of gears [2-4]. In this study, the pinion shaft of the differential of a minibus has been inspected. The minibus is a diesel vehicle driven at the rear axle and has a passenger capacity of 15 people. Maximum engine power is 90/4000 HP/rpm, and maximum torque is 205/1600 Nm/rpm. Its transmission box has manual system (5 forward, 1 back). The damage was caused by stopping and starting the minibus at a traffic lights. In this differential, entrance shaft which carries the pinion gear was broken. Various studies have been made to determine the type and possible reasons of the damage. These are:•studies carried out to determine the material of the shaft;•studies carried out to determine the micro-structure;•studies related to the fracture surface.There is a closer photograph of the fractured surfaces and fracture area in Fig. 4. The fracture was caused by taking out circular mark gear seen in the middle of surfaces.2. Experimental procedureSpecimens extracted from the shaft were subjected to various tests including hardness tests and metallographic and scanning electron microscopy as well as the determination of chemical composition. All tests were carried out at room temperature.2.1 Chemical and metallurgical analysisChemical analysis of the fractured differential material was carried out using a spectrometer. The chemical composition of the material is given in Table 1. Chemical composition shows that the material is a lowalloy carburizing steel of the AISI 8620 type.Hardenability of this steel is very low because of low carbon proportion. Therefore, surface area becomes hard and highly enduring, and inner areas becomes tough by increasing carbon proportion on the surface area with cementation operation. This is the kind of steel which is generally used in mechanical parts subjected do torsion and bending. High resistance is obtained on the surface and high fatigue endurance value can be obtained with compressive residual stressby making the surface harder [5-7].In which alloy elements distribute themselves in carbon steels depends primarily on the compound and carbide forming tendencies of each element. Nickel dissolves in the αferrite of the steel since it has less tendency to form carbides than iron Silicon combines to a limited extent with the oxygen present in the steel to form nonmetallic inclusions but otherwise dissolves in the ferrite. Most of the manganese added to carbon steels dissolves in the ferrite. Chromium, which has a somewhat stronger carbide-forming depends on the iron, partitions between the ferrite and carbide phases. The distribution of chromium depends on the amount of carbon present and if other stronger carbide-forming elements such as titanium and columbium amount of carbon present and if other stronger carbide-forming elements such as titanium and columbium are absent. Tungsten and molybdenum combine with carbon to form carbides is there is sufficient carbon present and if other stronger carbide-forming elements such da titanium and columbium are absent. Manganese and nickel lower the eutectoid temperature [8]. Preliminary micro structural examination of the failed differential material is shown in Fig. 5. It can be seen that the material has a mixed structure in which some ferrite exist probably as a result of slow cooling and high Si content. High Si content in this type of steel improves the heat treatment susceptibility as well asan improvement of yield strength and maximum stress without any reduction of ductility [9]. If the micro-structure cannot be inverted to martensite by quenching, a reduction of fatigue limit is observed.There are areas with carbon phase in Fig. 5(a). There is the transition boundary of carburization in Fig. 5(b) and (c) shows the matrix region without carburization. As far as it is seen in there photographs, the piece was first carburized, then the quenching operation was done than tempered. This situation can be understood from blind martensite plates.2.2 Hardness testsThe hardness measurements are carried out by a MetTest-HT type computer integrated hardness tester. The load is 1471 N. The medium hardness value of the interior regions is obtained as obtained as 43 HRC. Micro hard-ness measurements have been made to determine the chance of hardness values along cross-section be-cause of the hardening of surface area dueto carburization. The results of Vickers hardness measurement under a load of 4.903 N are illustrated in Table 2.2.3 Inspection of the fractureThe direct observations of the piece with fractured surfaces and SEM analyses are given in this chapter. The crack started because of a possible problem in the bottom of notch caused the shaft to be broken completely. The crack started on the outer part, after some time it continued beyond the centre and there was only a little part left. And this part was broken statically during sudden starting of the vehicle at the traffic lights. As a characteristic of the fatigue , there are two regions in the fractured surface. These are a smooth surface created by crack propagation and a rough surface created by sudden fracture. These two regions can be seen clearly for the entire problem as in Fig. 4. The fatigue crack propagation region covers more than 80% of the cross-section.Shaft works under the effect of bending, torsion and axial forces which affect repeatedlydepending on the usage place. There is a sharp fillet at level on the fractured section. For this reason, stress concentration factors of the area have been determined. K t = 2.4 value (for bending and tension), and K t = 1.9 value (for torsion) have been acquired according to calculations. These are quite high values for areas exposed to combined loading.These observations and analysis show that the piece was broken under the influence of torsion with low nominal stresses electron microscopy shows that the fracture has taken place in a ductile manner (Fig.6). There are some shear lips in the crack propagation region which is a glue of the plastic shear deformations. Fig. 7 shows the beach marks of the fatigue crack propagation. The distance between any lines is nearly 133 nm.3. ConclusionsA failed differential pinion shaft is analysed in this study. The pinion shaft is produced from AISI 8620 low carbon carburising steel which had a carbursing, quenching and tempering heat treatment process. Mechanical properties, micro structural properties, chemical compositions and fractographic analyses are carried out to determine the possible fracture reasons of the component. As a conclusion, the following statements can be drawn:•The fracture has taken place at a region having a high stress concentration by a fatigue procedure under a combined bending, torsion and axial stresses having highly reversible nature.•The crack of the fracture is initiated probably at a material defect region at the critical location.•The fracture is taken place in a ductile manner.•Possible later failures may easily be prevented by reducing the stress concentration at the critical locationAcknowledgementThe author is very indebted to Prof. S. Tasgetiren for his advice and recommendations during the srudy.References[1]Heisler H. Vehicle and engine technology. 2nd ed. London: SAE International; 1999.[2]Makevet E, Roman I. Failure analysis of a final drive transmission in off-road vehicles. EngFailure Anal 2002;9:579-92.[3]Orhan S, Aktu ¨rk N. Determination of physical faults in gearbox through vibrationanalysis. J Fac Eng Arch Gazi University 2003;18(3):97–106..[4]Tasgetiren S, Aslantas ? K, Ucun I. Effect of press-fitting pressure on the fatiguedamages of root in spur gears. Technol Res: EJMT 2004;2:21–9.[5]Nanawarea GK, Pableb MJ. Failures of rear axle shafts of 575 DI tractors. EngFailure Anal 2003;10:719–24.[6]Aslantas K, Tasgetiren S. A study of spur gear pitting formation and life prediction.Wear 2004;257:1167–75.[7]Savas V, O ¨ zek C. Investigation of the distribution of temperature on a shaft withrespect to the deflection. Technol Res: EJMT 2005;1:33–8.[8]Smith FW. Principles of materials science and engineering. 3rd ed. USA: McGraw-HillSeries; 1996. p. 517–18.[9]ASM metal handbook, vol. 1. Properties and selection, irons, steels, and highperformance alloys; 1991.[10]Voort GFV. Visual examination and light microscopy. ASM handbook metallographyand microstructures. Materials Park (OH): ASM International; 1991. p. 100–65.汽车差速器小齿轮轴的失效分析摘要差速器是用来降低速度增加扭矩并根据合适的角度向两轮传递动力。

驱动桥的构造外文文献翻译、中英文翻译、外文翻译

驱动桥的构造外文文献翻译、中英文翻译、外文翻译

附录AThe structure of driving axleThe driving axle is in the power power transmission the terminal, its basic function increases the torque which transmits by the drive shaft or the transmission gearbox, and power reasonable assignment for left and right driving gear, moreover also withstands the function vertical sets up, the longitudinal force and the transverse force between the road surface and the frame or the automobile body.The driving axle generally by the main gear box, the differential device, the wheel transmission device and the driving axle shell and so on is composed.1.Driving axle design:The driving axle design must satisfy following basic request:1). Choice main reduction gear ratios ought to be able to guarantee the automobile has the best power and the fuel economy.2). External dimensions must be small, guaranteed has the necessity ground clearance.3). Gears and other transmission piece works do steadily, the noise is small.4). Has the high transmission efficiency under each kind of rotational speed and the load.5). Under the guarantee enough intensity, the rigidity condition, should make every effort the quality to be small, under the reed the quality should be as far as possible small in particular, improves the automobile smoothness.6). Coordinated with the suspension fork guidance organization movement, regarding changes the driving axle, but also should coordinate with the rotation gear movement.7). Structures are simple, the processing technology capability is good, the manufacture is easy, disassembling, the adjustment is convenient.2.Driving axle classificationThe driving axle minute non-separation type with separates the type two big kinds.1).Non-separation type driving axleThe non-separation type driving axle also is called the integral-type driving axle, its rear axle drive pipe and main gear box shell with shaft casing rigidly connected whole Liang,thus the both sides rear axle and the driving gear swing related, passes the elastic part and the frame is connected.It by the driving axle shell 1, the main gear box, the differential device and the rear axle is composed.2). Separation type driving axleThe driving axle uses the independent suspension fork, namely the main gear box shell fixes on the frame, the both sides rear axle and the driving gear can be opposite in the rolling plane in the chassis have the relative motion to be called the separation type driving axle.In order to coordinates with the independent suspension fork, fixes the main gear box shell in the frame (or automobile body) on, the driving axle shell partition and through the hinge joint, or no longer has the driving axle shell other parts besides the main gear box shell.In order to meet the need which about the driving gear independence beats, between the differential device and between wheel rear axle each section connects with the universal joint.3.Drive axle of compositionMainly by the reducer drive, and half axle and drive axle shell, etc.1) .Main reducerThe speed reducer is usually used to change the direction of transmission, reduce speed and increase torque, guarantee cars have enough force and appropriate speed. Main reducer, have more single type, double, double speed reducer, wheel edges.a). Single main reducerBy a reduction gear reducer realization of single reducer, called. Its simple structure, light weight, dongfeng BQl090, light, medium sized truck was widely used in automobile.b). Double main reducerIn some large trucks, load demand is bigger than the slow, with single main reducer drive, driven gear diameter increases, affect to the ground clearance drive, so using twice. Usually called doublestage reducer. Two groups of double reduction gear reducer, increasing torsional twice slowdown.To improve the tapered gear pair of meshing smoothness and strength, the level of spiral bevel gears reduction gear pair is. Second gear pair is helical gears for support.Active tapered gear rotating, drive driven circular gear rotating, thus completing silver. Level Article 2 the initiative of cylindrical gears and driven tapered gear coaxial and rotate together, and bring about a follower of cylindrical gears rotate, 2. Because a follower ofcylindrical gears installed in differential shell, so, when a follower of cylindrical gears turning, through the differential and half shaft is driven wheel rotation.2).DifferentialAround half shaft are used to connect differential wheel, can make the sides with different velocity rotating torque simultaneously. Ensure the normal scroll wheel. Some more, in the car driver bridge or in the breakthrough of thansfer transmission shaft with differential between, also called the bridge between differential. Its role in the car is in turn or flat road to drive wheels, and generate differential between the role.Current domestic cars and other cars are adopted symmetric bevel gear ordinary differential. Symmetrical type gear differential planetary gear, half of planetary gear axle shaft gear, or a cross (direct axis) and differential shell, etc.Most current car using differential planetary gear, ordinary bevel gear differential by two or four conical planetary gear and planetary gear axle, two cone half shaft gear and differential shell, etc.3). Half axleHalf shaft are coming to the differential wheel, drive torque to move the car wheel rotation, the solid shaft. Due to the different structure, installation of hub axial force and the different also. Therefore, half shaft are divided into the floating, use, three/four floating three types.a). Howo fou-point suspending half axleGeneral big, medium-sized cars are adopted the floating structure. Half of the spline shaft inside with the half shaft with differential gears connected to the end of the half shaft are forging flanges, bolts and wheel connection. Hub through two far apart WenCheng tapered roller bearings in half a collar. Half a collar and driving axle shell pressure to drive, composition. Use this form, half shaft bearing no direct link with the bridge housing, half shaft driving torque and not only bear any moment under this half shaft are called "the floating" half axle. The so-called "float" means half shaft are not bending load.The float, the half axle shaft for lugs and made one. But there are some heavy trucks to lugs, and made the individual parts of the spline shaft in the half. Therefore, both ends of the spline shaft is used, can HuanTou.b). Use half axleUse of half axle within the same with the client, not withstand float bending-torsional. The client through a direct bearing on the inside of half axle shell. This means that willsupport the half axle under bending moment. Therefore, the half sleeve torque, except under bending moment, local use half shaft is called. This structure is mainly used for certain.The red flag brand limousines CA7560 type of thing. The half shaft are not bending moment, the client will inherit all external use, so called bending support.c). 3/4 floating half axleThree-quarters of floating half shaft are short of bending degree between use and the floating. This type of half axle currently used in XiaoWoChe, only on individual applications, such as M20 type car. Warsaw,4). The bridge housinga). Integral bridge housingIntegral bridge housing for the intensity and rigidity, and facilitate the good performance of the installation, adjustment and maintenance, and widely used. Integral bridge housing for manufacturing methods, which can be divided into different midway through the whole cast type, the steel casting and stamping steel welding etc.b). Drive axle shell segmentedSection type bridge housing generally fall into two, one will DuanLianCheng two by bolts. Bridge housing is segmented to casting and machining.附录B驱动桥的构造驱动桥处于动力传动系的末端,其基本功能是增大由传动轴或变速器传来的转矩,并将动力合理的分配给左、右驱动轮,另外还承受作用于路面和车架或车身之间的垂直立、纵向力和横向力。

汽车车辆类驱动桥的设计外文文献翻译、外文翻译、中英文翻译

汽车车辆类驱动桥的设计外文文献翻译、外文翻译、中英文翻译

汽车车辆类驱动桥的设计外文文献翻译、外文翻译、中英文翻译XXX毕业设计(论文)附录IDrive axle powertrain at the end of their basic function is to increase XXX, and a reasonable distribution ofpower to the left and right wheel, XXX between the vertical, XXX the main drive axle reducer, differential, XXX.The design of the Drive axle:Drive axle XXX:1. Select the main reduction ratio should be able to ensure the car has the XXX.2. Smaller size, XXX clearance.3. Gear and other pieces of the work of a smooth transmission,and small noise.4. In a variety of speed and load with a high transmission efficiency.5. XXX, XXX of small, especially under the mass-spring should be as small as possible XXX.6. And suspension movement-oriented coordination of steering drive axle, XXX.7. The structure of simple, good processing, manufacturing, easy disassembly, XXX.Drive axle classification-1-XXX毕业设计(论文)XXX-style-type with two broad categories.1. Non-disconnect-type drive axleNon-disconnect-type drive axle also known as integrated drive axle, the axlecasing and the XXX with shell shell and connected to a rigid beam,XXX with the frame components. It consists of drive axle housing 1, the mainreducer, differential and axle components.2. disconnect-type drive axle.Drive the use of independent suspension bridge, that is the main XXX vehicle chassis, on both sides of the axle and wheel in the horizontalplane as opposed to relative movement of the body is referred to as drive off thebridge.In order to match with independent suspension, the main reducer shell fixed at theframe (or body), the drive axle housing sub connected through the hinge, or inaddition to the main reducer shell outside the shell is no longer driven to other partsof the bridge. Wheel in order to meet the needs of independent jump up and down,between the differential and the wheel axle of the above connection between the useof universal joints.Drive axle componentsXXX by the main bridge reducer, differential, XXX.1. Main reducer assemblyUsed to change the main drive reducer general direction, to reduce speed andincrease torque, and ensure there is sufficient car drivers and the appropriate speed-2-XXX毕业设计(论文)skin. More types of the main reducer, a single-stage, dual-class, two-speed, such asWheel Speed Reducer.1) single-stage main reducerXXX of the devices, called single-stagereducer. Its structure is simple, light weight, such as Dongfeng BQl090 type light andmedium-sized trucks on a wide range of applications.2) two-stage main reducerLarger number of heavy-duty trucks, require a larger reduction ratio, the main useof a single-stage reducer drive, moving from gear to be XXX drive axle of the ground clearance, so the use of two XXX-stage reducer. There are two sets of two-stage reduction gear reducer, XXX.XXX, slowdown the first-class pair of XXX. Gears 2 is XXX.XXX, gear driven rotary driven round silver, XXX second stage XXX, and drive gear driven rotating cylinder, asecond-class speed. Due to the driven XXX, so that when the driven gear rotating cylinder, through the differentialand drive axle that is, the rotation of the wheels.2. DifferentialDifferential is designed to connect the axle around, on both sides of the XXX at the same time. To ensure the normal -3-XXX毕业设计(论文)XXX. Some multi-bridge-driven cars, in the sub-XXX, XXX role is to turn in the car or on uneven road surface,so that drive wheels before and after the XXX.At present, China-made cars and other types of vehicles in the basic use XXX, axle gears, planetary gear axis (cross-axis or a direct-axis) XXX of the shell and so on.XXX planet gears, planetary gearshaft, the two cone axle differential gear, and about the composition of the shell andso on.3.Auto semi-axleXXX, drive wheels spin,promote the solid axle car. As a result of the installation of wheel structure, and theforces of the axle are also different. Therefore, divided into full-floating axle,semi-floating, 3 / 4, three types of floating.1) full-floating axleGenerally large and medium-sized used car floating the whole structure. Axle withthe inner end of the XXX for the text on the axle casing. Rearaxle shell casing pressure and one pair to form the drive XXX forms, axle and axle housing no direct link so that only bear the drive-4-XXX毕业设计(论文)XXX, the axle referred to as "full-floating" axle.The so-called "floating", XXX axle.Full-floating axle, the outer end flange plate for one made with the axis. But there arealso a number of trucks to make a separate flange parts, and by XXX, at both ends of the axle spline, you can use for the first.2) semi-floating axleSemi-floating axle with the inner end of the same floating, not subject to XXX from direct client support through a bearing in the axle of theinner shell. This approach will support the outer end XXX,this short-XXX, but also to sustain the local moment, itis known as the semi-floating axle. This structure is mainly used in small passengercars.License Hongqi CA7560 icon for the type of drive axle XXX end of its moment, out client has to bear all the moment, so called semi-floatingbearing.3) 3 / 4 floating axle3 /4 XXX-floating and full floating between. At present the application of this XXX, M20vehicles.4. Automobile axle housing:1) the overall shell-style bridgeBridge shell due to the XXX, XXX, adjustment and maintenance, and XXX-5-XXX毕业设计(论文)housing due to different manufacturing methods XXX, pressed into the middle of casting XXX,XXX.2) sub-type drive axle housingSub-type XXX sections, XXX and processing easier.-6-XXX毕业设计(论文)附录II驱动桥处于动力传动系的末了,其根本功用是增大由传动轴或变速器传来的转矩,并将动力公道的分派给左、右驱动轮,别的还蒙受感化于路面和车架或车身之间的垂竖立、纵向力和横向力。

中英文文献翻译-驱动桥和差速器

中英文文献翻译-驱动桥和差速器

附录附录ADrive axle/differentialAll vehicles have some type of drive axle/differential assembly incorporated into the driveline. Whether it is front, rear or four wheel drive, differentials are necessary for the smooth application of engine power to the road.PowerflowThe drive axle must transmit power through a 90°angle. The flow of power in conventional front engine/rear wheel drive vehicles moves from the engine to the drive axle in approximately a straight line. However, at the drive axle, the power must be turned at right angles (from the line of the driveshaft) and directed to the drive wheels.This is accomplished by a pinion drive gear, which turns a circular ring gear. The ring gear is attached to a differential housing, containing a set of smaller gears that are splined to the inner end of each axle shaft. As the housing is rotated, the internal differential gears turn the axle shafts, which are also attached to the drive wheels.Fig 1 Drive axleRear-wheel driveRear-wheel-drive vehicles are mostly trucks, very large sedans and many sports car and coupe models. The typical rear wheel drive vehicle uses a front mounted engine and transmission assemblies with a driveshaft coupling the transmission to the rear drive axle. Drive in through the layout of the bridge, the bridge drive shaft arranged vertically in the same vertical plane, and not the drive axle shaft, respectively, in their own sub-actuator with a direct connection, but the actuator is located at the front or the back of the adjacent shaft of the two bridges is arranged in series. Vehicle before and after the two ends of the driving force of the drive axle, is the sub-actuator and the transmission through the middle of the bridge. The advantage is not only a reduction of the number of drive shaft, and raise the driving axle of the common parts of each other, and to simplify the structure, reduces the volume and quality.Fig 2 Rear-wheel-drive axleSome vehicles do not follow this typical example. Such as the older Porsche or Volkswagen vehicles which were rear engine, rear drive. These vehicles use a rear mounted transaxle with halfshafts connected to the drive wheels. Also, some vehicles were produced with a front engine, rear transaxle setup with a driveshaft connecting the engine to the transaxle, and halfshafts linking the transaxle to the drive wheels.Differential operationIn order to remove the wheel around in the kinematics due to the lack of co-ordination about the wheel diameter arising from a different or the same rolling radius of wheel travel required, inter-wheel motor vehicles are equipped with about differential, the latter to ensure that the car driver Bridge on both sides of the wheel when in range with a trip to the characteristics of rotating at different speeds to meet the requirements of the vehicle kinematics.Fig 3 Principle of differentialThe accompanying illustration has been provided to help understand how this occurs.1.The drive pinion, which is turned by the driveshaft, turns the ring gear.2.The ring gear, which is attached to the differential case, turns the case.3.The pinion shaft, located in a bore in the differential case, is at right angles to the axle shafts and turns with the case.4.The differential pinion (drive) gears are mounted on the pinion shaft and rotate with the shaft .5.Differential side gears (driven gears) are meshed with the pinion gears and turn with the differential housing and ring gear as a unit.6.The side gears are splined to the inner ends of the axle shafts and rotate the shafts as the housing turns.7.When both wheels have equal traction, the pinion gears do not rotate on the pinion shaft, since the input force of the pinion gears is divided equally between the two side gears.8.When it is necessary to turn a corner, the differential gearing becomes effective and allows the axle shafts to rotate at different speeds .Open-wheel differential on each general use the same amount of torque. To determine the size of the wheel torque to bear two factors: equipment and friction. In dry conditions, when a lot of friction, the wheel bearing torque by engine size and gear restrictions are hours in the friction (such as driving on ice), is restricted to a maximum torque, so that vehicles will not spin round. So even if the car can produce more torque, but also need to have sufficient traction to transfer torque to the ground. If you increase the throttle after the wheels slip, it will only make the wheels spin faster.Limited-slip and locking differential operationFig 5 Limited-slip differentialDifferential settlement of a car in the uneven road surface and steering wheel-driven speedat about the different requirements; but is followed by the existence of differential in theside car wheel skid can not be effective when the power transmission, that is, the wheel slipcan not produce the driving force, rather than spin the wheel and does not have enoughtorque. Good non-slip differential settlement of the car wheels skid on the side of the powertransmission when the issue, that is, locking differential, so that no longer serve a usefuldifferential right and left sides of the wheel can be the same torque.Limited-slip and locking differential operation can be divided into two major categories:(1) mandatory locking type in ordinary differential locking enforcement agencies toincrease, when the side of the wheel skid occurs, the driver can be electric, pneumatic ormechanical means to manipulate the locking body meshing sets of DIP Shell will be withthe axle differential lock into one, thus the temporary loss of differential role. Relatively simple structure in this way, but it must be operated by the driver, and good roads to stop locking and restore the role of differential.(2) self-locking differential installed in the oil viscosity or friction clutch coupling, when the side of the wheel skid occurs when both sides of the axle speed difference there, coupling or clutch friction resistance on the automatic, to make certain the other side of the wheel drive torque and the car continued to travel. When there is no speed difference on both sides of the wheel, the frictional resistance disappeared, the role of automatic restoration of differentials. More complicated structure in this way, but do not require drivers to operate. Has been increasingly applied in the car. About non-slip differential, not only used for the differential between the wheels, but also for all-wheel drive vehicle inter-axle differential/.Gear ratioThe drive axle of a vehicle is said to have a certain axle ratio. This number (usually a whole number and a decimal fraction) is actually a comparison of the number of gear teeth on the ring gear and the pinion gear. For example, a 4.11 rear means that theoretically, there are 4.11 teeth on the ring gear for each tooth on the pinion gear or, put another way, the driveshaft must turn 4.11 times to turn the wheels once. The role of the final drive is to reduce the speed from the drive shaft, thereby increasing the torque. Lord of the reduction ratio reducer, a driving force for car performance and fuel economy have a greater impact. In general, the more reduction ratio the greater the acceleration and climbing ability, and relatively poor fuel economy. However, if it is too large, it can not play the full power of the engine to achieve the proper speed. The main reduction ratio is more Smaller ,the speed is higher, fuel economy is better, but the acceleration and climbing ability will be poor.附录B驱动桥和差速器所有的汽车都装有不同类型的驱动桥和差速器来驱动汽车行驶。

驱动桥设计外文翻译

驱动桥设计外文翻译

Car drive axle design1 IntroductionThe structure form of the main reducer is based on the type of the gear and the way of the active gear and the driven gear.2 drive axleDrive axle in the tail end of the power transmission system, its basic function is to increase the torque came by the drive shaft or transmission, the reasonable distribution of power to the left and right driving wheels, and also bear role of road and the frame or body between vertical and longitudinal force and lateral force. The drive axle is composed of a main reducer, a differential, a wheel drive device and a drive axle housing.Reducer is the original motivation and independent of the working machine between the closed transmission, used to reduce speed and increase torque to meet the needs of a variety of working machinery. According to transmission form can be divided into three different for the gear reducer, worm reducer and planetary reducer; in accordance with the transmission of the series can be divided into single and multistage speed reducer; according to transmission layout situation can be divided for expansion, shunt type and coaxial type reducer. Gear reducer transmission efficiency and high reliability, long service life, maintenance is simple, and therefore the scope of application is very wide.2.1 main reducerThe main reducer gear has the spiral bevel gear type, the type of the double curved surface gear type, the type of the cylindrical gear and the worm gear and so on. At present, the main reducer gear of the automobile drive axle adopts spiral bevel gear. When the load is high, the work is stable, the noise is small, and the contact load on the tooth surface is low. So the use of single bevel gears.2.1.2 main reducer drive, driven bevel gear support formThe car driving axle design, so the use of cantilever installation. The using of the cantilever installation, ensure that the gear stiffness, active gear shaft neck should be increased, so that the distance between the two bearings than the distance of the cantilever high at least 2.5 times.3 the differential designCar in the exercise of the security, about two wheels at the same time the roll over the journey is often not equal, around two in the pressure is not equal, and the tread wear uneven, two wheel load is uneven and cause the wheel rolling radius does not match; the wheels touch the pavement conditions about different, exercises the resistance range, on the one hand will increase tire wear, power and fuel consumption, on the other hand will divert too difficult, through and handling stability is bad. Therefore, the left and right wheels of the drive axle are provided with a wheel differential mechanism.Differential is a differential transmission mechanism, used in the two output shaft torque distribution, and ensure two output shaft may rotate at different angular velocities, to ensure the driving wheels in various kinds of sports under the condition of power transmission, to avoid slipping between the tire and the ground. Differential according to its structural characteristics can be divided into gear type, convex wheel, worm wheel type and teeth embedded in a variety of forms, such as free wheel.4 half shaft For semi axis diameternot less than the diameter of the rod, the end part of the processing done slightly thicker, and appropriate to reduce spending less of the keyway depth, the tooth number must be a corresponding increase in, usually take 10 teeth (car half axle) to 18 teeth (truck half axle). The failure mode of the half shaft is basically too fatigue failure. The rod part of the axle shaft of the heavy duty truck is thicker, the outer end flange is relatively large, and the two ends of the shaft can be used as the half shaft structure with connection when no larger forging equipment is adopted, and the process is simplified by taking the same parameters. In the modern automobile half shaft, theis used quite widely, but also has the structure form of the rectangle or the trapezoidal .Shaft is one of the main parts of the machine, and all of the transmission parts of rotary motion must be installed on the axis to carry out the movement and power transmission. So the main function of the shaft is to support the rotating parts and the transmission of motion and power. According to the different load bearing, the shaft can be divided into shaft, mandrel and shaft of the third class, the relay under bending moment and bearing torque becomes the shaft. This type of shaft in the machine in the most common, only to withstand the bending moment and does not bear the torque a mandrel, the mandrel is divided into rotation and fixed mandrel mandrel two. Shaft which is only subjected to torque and does not bear the bending moment becomes the drive shaft.5 the bridge shell and the bridge shell accessories designThe main function of the drive axle housing is to support the quality of the vehicle, and is affected by the road surface reaction force and torque transmitted by the wheel, and the suspension is passed to the body. The drive shaft shell is a force transmitting member and the carrier, so the axle housing should meet the following requirements:1) with sufficient strength and stiffness, to ensure that the reducer gear mesh is normal anddoes not cause additional bending stress.2) under the premise of ensuring sufficient rigidity, as far as possible to reduce the car to improve the ride comfort.3) to ensure sufficient ground clearance.4) the structure craft is good, the cost is low.The bridge shell is a cross beam, the pivot point is located in the center of the tire, the load function in the steel plate spring seat, the average truck is used to improve the overall carrying capacity of the truck, the distance between the pivot point of the twin shaft is calculated according to the distance between the two.The maximum stress of the drive axle housing occurs near the steel plate spring. The force that causes the bending moment of the bridge shell is: the carrying capacity of the vertical load G2, the traction force F and its reaction torque M. And car shift when the tire lateral force Y2 external force in the drive axle housing, in order to simplify the calculation, just never sideslip BRDF is moving in a straight line calculated, and in terms of safety coefficient due consideration.The bending stress of the malleable cast iron bridge should not exceed 300m^2. The bending stress should not exceed 500m2 on the half shaft bushing and wheel axle of medium carbon alloy steel, and the shear stress should not exceed 250N/mm^2.Combines the actual situation of the vehicle, considering the overall expansion forming welding axle, so the material to consider ductility . We choose 16Mn.6 summaryThrough this design, it is now to design a product, only to feel that their knowledge is far from enough. There is a saying: it is never too late to learn. That's a bit of a point! Is my teacher, all my knowledge to learn!Through this design, the ability to check the manual has been greatly improved. Now, through the guidance of teachers, through their own practice, you can now go to the library to check the information, but also to look at what aspects of the information, the psychological is very clear, not so much as before.In other areas also have a lot of harvest, this graduation design makes me develop a meticulous work method. Before doing homework always give a lick and a promise, didn't have a bit of patience, sitting in the stool is not an under the heart, always with a fickle attitude to treat their own thing, now, I can very calm, very serious has been able to carry on. This may be to do the course design for me to leave things, this will be of great benefit to me later in the community.All in all, this design has made me a lot! thank you!轿车驱动桥设计1引言驱动桥处于动力传动系尾端,其基本功能是增加由传动轴或变速器传来的转矩,将动力合理分配给左、右驱动轮,且还承受作用路面和车架或车身之间的垂立、纵向力和横力。

差速器外文文献

差速器外文文献

差速器外文By ordinary differential planetary gear, the planet round rack (differential shell) and half axle gears, etc parts. By the power of the engine, direct drive shaft into differential planetary wheel frame, again by the planets wheel drive left, right, two half shaft are respectively driven wheels left and right. Differential design requirements meet: (left) + (right shaft speed shaft speed) = 2 (planets wheel frame speed). When the automobile moher, left, right wheel and planetary wheel frame three speed equal in balance, while in the car when turning three equilibrium state is destroyed, cause the medial wheel speed decreases, and the lateral wheel RPM increases.Automotive differential is driven axle Lord pieces. Its function is to both sides half shaft transmission power, while allowing both sides half shaft in different speed rotating, satisfy both sides wheel as pure rolling forms do isometric driving, reducing tire and the surface friction.Differential this adjustment is automatic, here involves "minimal energy consumption principle", namely earth all objects are inclined to consumption minimum state. For example a grain of beans into a bowl, beans will automatically stays in the bowl bottom and never stay in bowl wall, because bowl bottom is lowest energy position (potential), it automatically select static (minimum) without constantly kinetic energy movement. In the same way, Wheel in cornering would also automatically tendency of the lowest energy consumption in accordance with state, automatically turning radius adjusting right wheels speed.When cornering, due to the lateral friction wheel dragged phenomenon, medial wheel have slip phenomenon, two driving wheel now can produce two opposite direction of additional force, as a result of "minimal energy consumption principle", which inevitably leads on both sides of the wheel speed difference, thus destroyed three balance relationship, and through the half shaft are reflected in half axle gear, forcing planetary gear produce rotation, make the lateral half shaft speed faster, medial half axle planetismal, thus realize both sides wheel speed difference.If the drive wheels on either side of the drive axle shaft to the use of a whole rigid connection, the two wheels can only at the same Angle rotation. So, when the vehicle steering wheel drive, due to the lateral than medial wheels moved across the distance is big, will make the lateral wheels in rolling produced simultaneously slippery procrastinate, and medial wheels in rolling produced simultaneously slip. Even the car run straight road gravamen, because although pavement straight but tyres or rolling radius range (tyre manufacture error, wear different, by the uneven or pneumatic ranging caused by the wheels of sliding).Wheel when not only aggravate sliding tire wear, increase power and fuel consumption, still can make the vehicle steering difficulties, braking performance becomes poor. For the wheel as far as possible will not occur in the structure of sliding, must guarantee the wheels can come with different Angle rotation.Axis between differential: usually driven wheel bearings for support on spindle, enable to any Angle rotation, and drive wheels respectively with two root half axle rigid connection, in between two root half shaft with differential. This differential also called shaft between differential.slowly, right wheels faster, with different speed to compensate for the distance of the differences.If after axles make it a whole, he couldn't do it on both sides of the wheel speed difference, namely can't do an automatic adjustment. In order to solve this problem, as early as in a hundred years ago, France Renault automotive company founder luis Renault will design a differential in this thing.Modern vehicles on the differential usually according to its work characteristics into gear type differential and slip differential two kinds big.The structure of the Cherokee open-die differential is typical of planetary gear set structure, only the sun wheel and outside the pinion gear ring are the same. In this planetary gear set, driving gear is planet shelf, passive round is two SUNS wheel. Through the planetary gear set the transmission properties we know, if the planet shelf as ZhuDongZhou, two SUNS wheel speed and rotation direction is not affirmatory, even two SUNS wheel rotation direction is the opposite.Vehicle condition, this differential moher, feature is to two and a half shaft transmission torque of the same. In a driving wheel impending case, if the drive shaft rotation, have adhesion is uniform the driving wheels of driving force, if there is no drive shaft rotation is accelerated, have adhesion the driving wheels driving force equals impending wheel Angle acceleration and rotary inertia of the product.Vehicle turning tires don't skid condition, connect the two halves of the differential shaft torque direction is opposite, give the vehicle driving forward, and only the inside of the wheel, the planet shelf and medial sun round by the isokinetic transmission between became deceleration transmission, driving sensation is accelerated speed corners than straight more powerful.The advantages of open-die differential is installed in the pavement turned driving on the best effect. Weakness is in a driving wheel loss adhesion, under the situation of another nor driving force.Open-die differential is the suitable scope that all paving road traffic, front axle and rear axle driver drive can be installed.2. Limited slip differentialLimited slip differential used for parts make up open-die differential transmission in off-road defects, it is in the open differential institution improved, and the differential shell side increase friction between gear piece, corresponding to the planetary gear set speaking, is the planet shelf and the sun round between increased friction slices, increase the sun wheel and planet shelf free rotating resistance torque.Limited slip differential provide additional torque, and friction slices transfer of power and two driving wheel rotation difference of concerned.In open-die differential structure to improve on LSD, cannot produce 100% limited slip, because the limited slip coefficient, the higher the vehicles to the characteristics of the poor.LSD have open-die differential transmission characteristics and mechanical structure. Advantage is to provide certain limited slip torque, defect is turning performance becomes poor, friction slices limited life.LSD is the suitable scope paving road surface and mild off-road. Usually used for the drive. Former drove generally does not installed, because LSD interfere steering, limited slip coefficient, the greater the steering the more difficult.Three. The lock type differential (mechanical locking check, electric the lock, pneumatic locking check)In order to guarantee the off-road vehicles in complex conditions, driving performance through certain mechanical structure of the differential locked achieve two half axle synchronous rotation. Through the analysis of planetary gear set is the planetary gear set of gear mechanisms locked, guarantee the planet shelf wheel with the sun, and two SUNS round between the transmission ratio between is 1:1. Can the sun to the wheel and planet shelf the lock, can put the planet shelf and planetary gear locked, still can put two SUNS wheel locked.The lock type differential, without the lock, its transmission characteristics and open-die differential exactly the same as that in the lock, under the situation of transmission ratio was fixed for 1:1.The advantages of this differential in off-road self-evident that provides the biggest drawback is the driving force, the differential lock up the situation, vehicle steering extremely difficult, Existing single wheel inherit engine 100% torque possible, half shaft will because torque excessive deformation or break, Vehicles in the process of steering bearings, two and a half by opposite torque, if both sides tires adhesion are large, would wring half axle. Moreover, this kind of differentials, the vehicle process execution lock up the action will produce larger noise.Four. Electronic differentials lockElectronic differentials lock and the aforesaid compared, without changing the structure and characteristics of open-die differential, but use ABS or EBD systemto implement unilateral braking skid wheels movement, limit of two driving wheel rotation difference, guarantee the drive wheels momentum.Advantages: good safety, won't damaged vehicle. Faults: need ABS and costly; EBD system, In the harsh off-road conditions, electronic product reliability as mechanical products; Unilateral wheel driving force, as the lock type differential. 1, gear type differential:When driving wheel rotation difference exists about when, differential assigned to slow turns driving wheel torque is greater than turn fast driving wheel torque. This kind of differential torque partitioning characteristics can satisfy the car in good pavement moving. But when the automobile in bad the road, but serious influence through capacity. E.g. when a car driving wheel into muddy road, although another driving wheel in good road, the car was often cannot advance (known as slips). At this point in the muddy road on the driving wheels in-situ slip, in good road wheels is motionless. This is because in the muddy road wheels and road surface adhesion between the lesser, road only through this round of half-and-half shaft role of smaller reaction torque, therefore differential assigned to this round of torque also small, although another driving wheel and better road to improve adhesion of the larger, but because average distribution characteristics of torque, which make this drive wheels can only also assigned to the drive wheels with slip equal amounts of torque, so that the driving force to overcome driving resistance, cars can't advance and motivation is expended in slip driving wheel. At this time to floor not only made the car ahead, instead of waste fuel, accelerate parts wear, especially tire wear is intensified. Effective solutions are: slicer slip driving wheel under the mud or in this wheel mat dry soil, gravel, branches, hay, etc. 2, slip differential:In order to improve the car in a bad way through capacity, some off-road vehicle and limousines screwup slip differential. Slip differential characteristics are, when driving wheel in a bad way side slip, can make the most or all torque in good road to the driving wheels, to take full advantage of the drive wheels adhesion to generate enough force, that car start or continue to drive.1. Differential shell there cannot be any properties of crack, shell and planetary gear gaskets, differential half axle gear contact between, should be smooth without groove, If there is a slight groove or wear, can continue to use after grinding, otherwise must be changed or be repaired.2 the planetary gear differential shell and planetary gear wheel when the fitting clearance must not be more than 0.1-0.15 mm, half axle gear shaft neck and shell with holes for clearance fit, should have no obvious loose feeling, otherwise desert must be changed or repair.。

汽车驱动桥外文文献翻译、中英文翻译、外文翻译

汽车驱动桥外文文献翻译、中英文翻译、外文翻译

汽车驱动桥外文文献翻译、中英文翻译、外文翻译Drive AxleIn any vehicle。

there is always a drive ___ of whether it's a front。

rear。

or four-wheel drive。

differentials are crucial for the smooth n of engine power to the road.The drive axle must be able to transmit power through a 90-___ front-engine/rear-wheel drive vehicles。

the flow of power moves from the engine to the drive axle in a ___。

at the drive axle。

the power must be turned at a right angle (from the line of the driveshaft) and directed to the drive wheels.To do this。

a n drive gear is used to turn a ___ to the inner end of each axleshaft。

As the housing rotates。

the internal differential gears turn the axle shafts。

which are also attached to the drive wheels.二、中文翻译驱动桥所有车辆都有一种驱动桥/差速器组件集成到传动线中。

无论是前驱、后驱还是四驱,差动器都是平稳将发动机动力传递到路面上的必要条件。

驱动桥必须能够通过90度角传递动力。

在传统的前置发动机/后驱车辆中,动力流从发动机到驱动桥的方向是近似直线的。

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JG Hardt,DW SheaDrive axle/differentialAll vehicles have some type of drive axle/differential assembly incorporated into the driveline. Whether it is front, rear or four wheel drive, differentials are necessary for the smooth application of engine power to the road.PowerflowThe drive axle must transmit power through a 90°angle. The flow of power in conventional front engine/rear wheel drive vehicles moves from the engine to the drive axle in approximately a straight line.However,at the drive axle, the power must be turned at right angles(from the line of the driveshaft)and directed to the drive wheels.This is accomplished by a pinion drive gear, which turns a circular ring gear. The ring gear is attached to a differential housing, containing a set of smaller gears that are splined to the inner end of each axle shaft. As the housing is rotated, the internal differential gears turn the axle shafts, which are also attached to the drive wheels.Fig1 Drive axleRear-wheel driveRear-wheel-drive vehicles are mostly trucks, very large sedans and many sports car and coupe models.The typical rear wheel drive vehicle uses a front mounted engine and transmission assemblies with a driveshaft coupling the transmission to the rear drive axle. Drive in through the layout of the bridge, the bridge drive shaft arranged vertically in the same vertical plane, and not the drive axle shaft, respectively, in their own sub-actuator with a direct connection,but the actuator is located at the front or the back of the adjacent shaft of the two bridges is arranged in series. Vehicle before and after the two ends of the driving force of the drive axle, is the sub-actuator and the transmission through the middle of the bridge. The advantage is not only a reduction of the number of drive shaft, and raise the driving axle of the common parts of each other, and to simplify the structure, reduces the volume and quality.Fig2 Rear-wheel-drive axleSome vehicles do not follow this typical example.Such as the older Porsche or Volkswagen vehicles which were rear engine, rear drive. These vehicles use a rear mounted transaxle with halfshafts connected to the drive wheels. Also, some vehicles were produced with a front engine, rear transaxle setup with a driveshaft connecting the engine to the transaxle,and halfshafts linking the transaxle to the drive wheels.Differential operationIn order to remove the wheel around in the kinematics due to the lack of co-ordination about the wheel diameter arising from a different or the same rolling radius of wheel travel required, inter-wheel motor vehicles are equipped with about differential,the latter to ensure that the car driver Bridge on both sides of the wheel when in range with a trip to the characteristics of rotating at different speeds to meet the requirements of the vehicle kinematics.Fig3 Principle of differentialThe accompanying illustration has been provided to help understand how this occurs.1.The drive pinion, which is turned by the driveshaft,turns the ring gear.2.The ring gear, which is attached to the differential case,turns the case.3.The pinion shaft, located in a bore in the differential case, is at right angles to the axle shafts and turns with the case.4.The differential pinion (drive) gears are mounted on the pinion shaft and rotate with the shaft .5.Differential side gears (driven gears) are meshed with the pinion gears and turn with the differential housing and ring gear as a unit.6.The side gears are splined to the inner ends of the axle shafts and rotate the shafts as the housing turns.7.When both wheels have equal traction, the pinion gears do not rotate on the pinion shaft,since the input force of the pinion gears is divided equally between the two side gears.8.When it is necessary to turn a corner, the differential gearing becomes effective and allows the axle shafts to rotate at different speeds .Open-wheel differential on each general use the same amount of torque. To determine the size of the wheel torque to bear two factors: equipment and friction. In dry conditions, when a lot of friction, the wheel bearing torque by engine size and gear restrictions are hours in the friction (such as driving on ice),is restricted to a maximum torque, so that vehicles will not spin round. So even if the car can produce more torque, but also need to have sufficient traction to transfer torque to the ground. If you increase the throttle after the wheels slip, it will only make the wheels spin faster.Fig4 Conventional differentialLimited-slip and locking differential operationFig5 Limited-slip differentialDifferential settlement of a car in the uneven road surface and steering wheel-driven speed at about the different requirements;but is followed by the existence of differential in the side car wheel skid can not be effective when the power transmission, that is, the wheel slip can not produce the driving force, rather than spin the wheel and does not have enough torque. Good non-slip differential settlement of the car wheels skid on the side of the power transmission when the issue, that is, locking differential, so that no longer serve a useful differential right and left sides of the wheel can be the same torque.Limited-slip and locking differential operation can be divided into two major categories:(1)mandatory locking type in ordinary differential locking enforcement agencies to increase, when the side of the wheel skid occurs, the driver can be electric, pneumatic or mechanical means to manipulate the locking body meshing sets of DIP Shell will be with the axle differential lock into one, thus the temporary loss of differential role. Relatively simple structure in this way, but it must be operated by the driver, and good roads to stop locking and restore the role of differential.(2)self-locking differential installed in the oil viscosity or friction clutch coupling, when the side of the wheel skid occurs when both sides of the axle speed difference there,coupling or clutch friction resistance on the automatic, to make certain the other side of the wheel drive torque and the car continued to travel. When there is no speed difference on both sides of the wheel,the frictional resistance disappeared,the role of automatic restoration of differentials. More complicated structure in this way, but do not require drivers to operate. Has been increasingly applied in the car. About non-slip differential, not only used for the differential between the wheels, but also for all-wheel drive vehicle inter-axle differential/.Gear ratioThe drive axle of a vehicle is said to have a certain axle ratio. This number (usually a whole number and a decimal fraction) is actually a comparison of the number of gear teeth on the ring gear and the pinion gear. For example, a 4.11 rear means that theoretically, there are 4.11 teeth on the ring gear for each tooth on the pinion gear or, put another way, the driveshaft must turn 4.11 times to turn the wheels once. The role of the final drive is to reduce the speed from the drive shaft, thereby increasing the torque. Lord of the reduction ratio reducer, a driving force for car performance and fuel economy have a greater impact. In general, the more reduction ratio the greater the acceleration and climbing ability,and relatively poor fuel economy.However, if it is too large, it can not play the full power of the engine to achieve the proper speed. The main reduction ratio is more Smaller,the speed is higher,fuel economy is better,but the acceleration and climbing ability will be poor.翻译驱动桥和差速器所有的汽车都装有不同类型的驱动桥和差速器来驱动汽车行驶。

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