机械毕业设计英文外文翻译590专用车辆的特点 - 副本
机械毕业设计英文外文翻译543雨 刷 - 副本
附录AWindshield WiperBackgroundWindshield wipers are used to clean the windshield of a car so that the driver has an unobstructed view of the road. A typical wipe angle for a passenger car is about 67 degrees. The blades are 12-30 in (30-76 cm) long with lengths increasing in 2-in (5-cm) increments.HistoryThe history of the windshield wiper began with the invention of the automobile. Most transportation vehicles did not have wipers. Horse-drawn carriages and trucks moved at slow speeds, and glass was not needed to protect the driver or passengers or to act as a windbreak.The first windshield wipers were brushes. Inventor J. H. Apjohn came up with a method of moving two brushes up and down on a vertical plate glass windshield in 1903. In the same year, Mary Anderson devised a swinging arm that swept rain off the windshield when the driver moved a lever located inside the car. Anderson patented her invention of the mechanical windshield wiper in 1905, and it became standard equipment by 1913. Electric motors were not used yet to power automobile essentials or accessories, and Anderson's device had a drawback. Without another power source, a driver had to use one hand to move the lever. The driver's other hand steered the car (with either a wheel or steering tiller) andworked the stick-mounted gear shift and brake grips standing on the floor of the car or outside the driver's side on the running board.Rubber strips replaced brushes as the cleaning tools on wipers in 1905. Unfortunately, the hazardous need for drivers to wipe windshields while driving was not eliminated until 1917. The solution was to use an electric motor to move a single wiper with a long rubber blade back and forth. Hawaiian dentist Dr. Ormand Wall invented the automatic wiper by placing an electric motor in the top center of the windshield so the wiper arced down over the hood of the car in a semi-circular or rainbow shape. Wipers were one of the first electrical devices in automobiles after the electric starter was developed in 1912. Most wipers on cars before 1930 were paired and hung down from the top of the windshield. They were moved to the base of the windshield as electrical systems became more complicated.Windshield washers were added to the wiper on/off levers, and these required spray nozzles in front of the windshield, a tank for washer fluid in the engine compartment, and electrical connections to coordinate these operations. In 1962, Bob Kearns invented the intermittent wiper with intervals and speeds that the driver could change. The advent of electronic systems with fuses and circuit breakers to operate, regulate, and coordinate electrical components expanded the possibilities for more diverse wipers. Wipers were added to headlights in the 1980s, requiring connections between the lighting and wiper systems. In the 1990s, microsensors were built into windshields to detect rain on the windshield, activate the wipers, and adjust speed and intermittent use for the amount of rain.Raw MaterialsThe manufacturer purchases all of the parts from companies that specialize in fabricating parts from aluminum and steel, rubber blades, plastic bushings for the linkages, and the motors. Windshield wipers and windshield wiper systems (with motors) are different assemblies; some manufacturers make both, and others produce wipers only.The connecting and drive links and the pivots that move the wipers are made of galvanized steel. Galvanization is the process of applying zinc coating to steel to protect it from corrosion. Drive arms for boats and vehicles used in the marine industry are made of stainless steel that resists damage from salt water. The wiper suspension and claws are also galvanized steel. The galvanizing zinc coating is easier to paint than uncoated steel. Steel is also the material in the small parts of wipers, such as washers, screws, nuts, springs, and brackets.The blade frame is made from aluminum. The blades are made of natural rubber or synthetic compounds. Some rubber blades are composites of soft rubber on the wiping edge (the squeegee surface) and firm rubber that supports the wiping edge in the rest of the blade.Other materials that comprise parts of windshield wipers are rubber for washers in the pivots and plastic bushings that line holes for connecting parts of the linkage. The wiper suspension is typically painted black. If the wiper manufacturer also builds wiper systems, motors are purchased from subcontractors. The motors are contained in steel housings and include permanent magnet motors wound with copper wire. Each housing has connections for the electrical wires that are part of the vehicle and wiring harnesses are furnished specific to operating the wipers. Each motor also contains one or more electronic circuits depending on the sophistication of the system that the motor controls.DesignWindshield wipers are designed and made to clear water from a windshield. Most cars have two wipers on the windshield, and they may have one on the rear window and one on each headlight. The wiper parts visible from outside the car are the rubber blade, the wiper arm holding the blade, a spring linkage, and parts of the wiper pivots. The wiper itself has up to six parts called pressure points or claws that are small arms under the wiper. The claws distribute pressure from the wiper along the back of the blade. This is described as a balance beam with a suspension system, where the wiper is the beam and the claws are the suspension components. The claws keep the blade flexed against the windshield to distribute even pressure to clean the glass all along the blade. More claws usually distribute the pressure better and are suited to large or highly curved windshields.Although the rubber is the familiar part of the blade, the blade actually includes a metal strip called a blade frame with a slot along the length of the frame and replacement holes in the frame. The replacement holes provide access for replacing the rubber blade with a refill. The blade on its aluminum frame can also be changed as a unit.The standard two windshield wipers are usually operated as a single-motor, tandem scheme with one wiper on the driver's side and one positioned near the middle of the windshield that moves across the passenger's view. The wipers are secured to pivots. A wiper and pivot are mounted on brackets at both ends of a long rod called the connecting link, and, as the force from the motor pushes on the driver's end of the connecting link, it in turn moves the other wiper. The connecting link is attached to another long rod called the drive link near the wiper motor. A slender spring linkage ties the pivot to the drive link to return the wiper toits resting or park position, hug the wiper close to the windshield, and keep it attached to the car if the links are damaged.Between the motor and the drive link, a linkage system consisting of a cam (another short rod) and pivot, a gear output shaft, and a worm gear controls the force of the motor delivered to the drive arm. The worm gear slows the speed of the motor while multiplying its torque (force). The gear allows a small motor to produce enough force to move the blades across the glass. This description is based on using a single motor to drive both wipers. If one motor powers each wiper, more links are needed to move the two wipers together in a so-called unitized motor system.This multiplied force is required to accelerate the blades from being stopped at bothWindshield wiper systems.ends of their movement, to resist the friction of the rubber against the glass, to resist the friction of the rubber on dirt on the glass, and to oppose wind pressure on the windshield.Quality ControlDuring assembly, the workers observe the conditions of the parts during their work, but their only specific quality control activity is to check the operation of the motors by turning them on to make sure they start and by listening to the sounds they make as indications of performance.The last inspection is performed when the assemblies are complete and before the wipers and systems are packed. The manufacturing director or final quality control inspectors look at the general appearance of the assemblies, confirm that the wipers have been sized and angled correctly for their sweep, and check that the assemblies are in the park position. The director or inspectors also check to see that the correct accessories are ready to be packed with the assemblies.Byproducts/WasteSmall quantities of steel and aluminum scraps from trimmings or rejected or damaged parts are collected in bins and sold to salvage dealers who, in turn, sell them to metal manufacturers who melt the scrap down for recycling. Packaging from received parts is also collected and recycled.The FutureAs of 2002, windshield wipers and wiper systems are evolving because of changes in automobiles and other vehicles, technical improvements, and consumer demand. Wiper blades are as much as 30 in (76 cm) long, creating more resistance as they clean the windshield. Night-vision screens for windshields are in development, and these also increase resistance and change the dimensions needed for wipers. Blades are being improved with increasingly flexible rubber, so-called "boots" that fit around the blades to keep out ice and snow, and nonstick coatingson the squeegee edges of the blades to keep oil and wax from adhering and aging them.Motor systems are also being increased in voltage to power longer wipers and more accessories. Engineers are investigating fully automated systems that do not require any actions by drivers to start and stop wiper systems. Inventors expect the capabilities of the rain-detecting sensors available in the late 1990s to widen to prompt the wipers to clean dirty windshields with no rain, for example. Windshield wipers are among most reliable automotive devices—the design life of a wiper system is 1.5 million wipes.附录B雨刷背景雨刷是专门用来清洁车辆上的挡风玻璃,这样司机就可以清晰地看到前方的道路了。
机械毕业设计英文外文翻译396驱动桥 - 副本
附录A 英文文献Drive AxleAll 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.Rear-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 shaftof 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 axle Some 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 differential The 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 differential Differential 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 thesame 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 fueleconomy 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。
现代包装机械设备毕业课程设计外文文献翻译、中英文翻译
1 英文文献翻译1.1 Modern PackagingAuthor：Abstract1. Changing Needs and New RolesLooking back, historical changes are understandable and obvious. That all of them have had an impact on the way products are brought, consumed and packaged is also obvious. What is not so obvious is what tomorrow will bring. Yet, it is to the needs, markets, and conditions of tomorrow that packaging professionals must always turn their attention.The forces that drove packaging during the Industry Revolution continue to operate today. The consumer society continues to grow and is possibly best described by a 1988s bumper sticker, “Born to Shop”. We consume goods today at a rate 4 to 5 times greater than we did as recently as 1935. Most of these goods are not essential to survival; they constitute what we may call “the good life”.In the second half of the 20th century， the proliferation of goods was so high that packaging was forced into an entirely new role, that of providing the motivation rather than presenting the goods itself. On a shelf of 10 competing products, all of them similar in performance and quality, the only method of differentiating became the package itself. Marketer aimed at lifestyles, emotional values, subliminal images, features, and advantages beyond the basic product rather than the competitor’s. In some in instances, the package has become the product, and occasionally packaging has become entertainment.A brand product to carry the product manufacturer or product sales of theretailer’s label, usually by the buyer as a quality assessment guidance. In some cases, competing brands of product quality is almost no difference, a difference is the sale of its packaging. An interesting visually attractive packaging can give a key marketing advantage and convince impulse spending. However, the packaging should accurately reflect the quality of products/brand value in order to avoid the disappointment of consumers, encourage repeat purchases and build brand loyalty. Ideally, the product should exceed customer expectations.2. Packaging and the Modern Industrial SocietyThe importance of packaging to a modern industrial society is most evident when we examine the food-packaging sector. Food is organic in nature, having an animal or plant source. One characteristic of such organic matter is that, by and large, it has a limited natural biological life.A cut of meat, left to itself, might be unfit for human consumption by the next day. Some animal protein products, such as seafood, can deteriorate within hours.The natural shelf life of plant-based food depends on the species and plant involved. Pulpy fruit portions tend to have a short life span, while seed parts, which in nature have to survive at least separated from the living plant are usually short-lived.In addition to having a limited natural shelf life, most food is geographically and season-ally specific. Thus, potatoes and apples are grown in a few North American geographical regions and harvest during a short maturation period. In a world without packaging，we would need to live at the point of harvest to enjoy these products, and our enjoyment of them would be restricted to the natural biological life span of each. It is by proper storage, packaging and transport techniques that we are able to deliver fresh potatoes and apples, or the products derived from them, throughout the year and throughout the country. Potato-whole,canned, powdered, flaked, chipped, frozen, and instant is available, anytime, anywhere. This ability gives a society great freedom and mobility. Unlike less-developed societies, we are no longer restricted in our choice of where to live, since we are no longer tied to the food-producing ability of an area. Food production becomes more specialized and efficient with the growth of packaging. Crops and animal husbandry are moved to where their production is most economical, without regard to the proximity of a market. Most important, we are free of the natural cycles of feast and famine that are typical of societies dependent on natural regional food-producing cycles.Central processing allows value recovery from what would normally be waste by products of the processed food industry from the basis of other sub-industries. Chicken feathers are high in protein and, properly mill and treated, can be fed back to the next generation of chickens. Vegetable waste is fed to cattle or pigs. Bagasse, the waste cane from sugar pressing, is a source of fiber for papermaking. Fish scales are refined to make additives for paints and nail polish.The economical manufacture of durable goods also depends on good packaging.A product's cost is directly related to production volume. The business drive to reduce costs in the supply chain must be carefully balanced against the fundamental technical requirements for food safety and product integrity, as well as the need to ensure an. efficient logistics service. In addition, there is a requirement to meet the aims of marketing to protect and project brand image through value-added pack design. The latter may involve design inputs that communicate distinctive, aesthetically pleasing, ergonomic, functional and/or environmentally aware attributes. But for a national or international bicycle producer to succeed, it must be a way of getting the product to a market, which may be half a world away. Again, sound packaging, in this case distributionpackaging, is a key part of the system.Some industries could not exist without an international market. For example, Canada is a manufacturer of irradiation equipment, but the Canadian market (which would account for perhaps one unit every several years) could not possibly support such a manufacturing capability. However, by selling to the world, a manufacturing facility becomes viable. In addition to needing packaging for the irradiation machinery and instrumentation, the sale of irradiation equipment requires the sale packaging and transport of radioactive isotopes, a separate challenge in itself. In response to changing consumer lifestyles, the large retail groups and the food service industry development. Their success has been involved in a competition fierce hybrid logistics, trade, marketing and customer service expertise, all of which is dependent on the quality of packaging. They have in part led to the expansion of the dramatic range of products offered, technology innovation, including those in the packaging. Supply retail, food processing and packaging industry will continue to expand its international operations. Sourcing products around the world more and more to assist in reducing trade barriers. The impact of the decline has been increased competition and price pressure. Increased competition led to the rationalization of industrial structure, often in the form of mergers and acquisitions. Packaging, it means that new materials and shapes, increased automation, packaging, size range extension of lower unit cost. Another manufacturer and mergers and acquisitions, the Group's brand of retail packaging and packaging design re-evaluation of the growing development of market segmentation and global food supply chain to promote the use of advanced logistics and packaging systems packaging logistics system is an integral part of, and played an important role in prevention in the food supply or reduce waste generation.3. World Packaging.This discussion has referred to primitive packaging and the evolution of packaging functions. However, humankind's global progress is such that virtually every stage in the development of society and packaging is present somewhere in the world today. Thus, a packager in a highly developed country will agonize over choice of package type, hire expensive marketing groups to develop images to entice the targeted buyer and spend lavishly on graphics. In less-developed countries, consumers are happy to have food, regardless of the package. At the extreme, consumers will bring their own packages or will consume food on the spot, just as they did 2000 years ago.Packagers from the more developed countries sometimes have difficulty working with less-developed nations, for the simple reason that they fail to understand that their respective packaging priorities are completely different. Similarly, developing nations trying to sell goods to North American markets cannot understand our preoccupation with package and graphics.The significant difference is that packaging plays a different role in a market where rice will sell solely because it is available. In the North American market, the consumer may be confronted by five different companies offering rice in 30 or so variations. If all the rice is good and none is inferior, how does a seller create a preference for his particular rice? How does he differentiate? The package plays a large role in this process.The package-intensive developed countries are sometimes criticized for over packaging, and certainly over-packaging does exist. However, North Americans also enjoy the world's cheapest food, requiring only about 11 to 14% of our disposable income. European food costs are about 20% of disposable income, and in the less-developed countries food can take 95%of family income.4. The status and development trend of domestic and international packaging machineryWorldwide, the history of the development of the packaging machinery industry is relatively short, science and technology developed in Europe and America in general started in the 20th century until the 1950s the pace greatly accelerated.From the early 20th century, before the end of World War II World War II，medicine，food, cigarettes，matches，household chemicals and other industrial sectors, the mechanization of the packaging operations; the 1950s, the packaging machine widely used common electric switches and tube for the main components of the control system to achieve the primary automation; 1960s, Electrical and optical liquid-gas technology is significantly increased in the packaging machine, machines to further expand on this basis a dedicated automated packaging line; the 1970s, the micro- electronic technology into the automation of packaging machines and packaging lines, computer control packing production process; from the 1980s to the early 1990s, in some field of packaging, computer, robot application for service, testing and management, in preparation for the over-flexible automatic packaging lines and "no" automatic packaging workshop.Actively promoted and strong co-ordination of all aspects of society, and gradually establish a packaging material, packaging, printing, packaging machinery and other production sectors, and corresponding to the research, design, education, academic, management and organization, and thus the formation of independent and complete. The packaging of light industrial system, and occupies an important place in the national economy as a whole.Based on recent years data that members of the World Packaging Alliance output value of the packaging industry accounts for about 2% of the total output value of the national economy; in which the proportion of packaging machinery, though not large, but the rapid development of an annual average of almost growing at a rate of about 10%. Put into use at the packaging machine is now more than thousand species of packaging joint machines and automated equipment has been stand-alone equate. According to the new technological revolution in the world development trend is expected to packaging materials and packaging process and packaging machinery will be closely related to obtain the breakthrough of a new step, and bring more sectors into the packaging industry.China Packaging Technology Association was established in 1980. Soon, the China National Packaging Corporation have been born. Since then, one after another in the country organized a national and international packaging machinery exhibition, seminars, also published I had the first ever "China Packaging Yearbook and other packaging technology books. All this indicates that China is creating a new packaging historical perio d.1.2中文翻译现代包装1、不断变化的需求和新的角色,回顾以往,包装所带来明显的历史性变化是可以理解的, 一个产品包装方式的给他们的销量带来的影响也是显而易见的。
中英文文献翻译—专业车辆的特点
附录 B1. 汉语翻译专业车辆的特点随着汽车工业和市场的发展，社会对汽车运输的效率和经济性以及各种功能的要求也越来越高，从而使汽车运输工具向专业化发展成为必然规律。
从某种意义上说，汽车基本型仅能满足“量”的要求，完成一般的汽车运输，只有专业车辆才能更有效地发挥汽车运输的经济效益和专用功能，从而满足“质”的要求。
汽车运输专用车辆能保持运输货物的物理状态和质量，采用普通型运输，是有些货物在运输过程中可能会发生腐烂变质，在长途运输中，如肉类、蛋类若没有冷冻保鲜专业设备，尤其是在炎热的夏天肯定会变质。
如活鱼苗若没有防震、保湿、充氧气等专用功能，在长途运输中会死亡。
有些货物在运输过程中容易流式损坏，如水泥、玻璃、谷物、蔬菜等。
据我国经委运输研究报告，一些地区的水果、肉、鱼、鲜蛋不能及时外运，造成腐烂变质，年亏损达10亿元之多，而另一些地区却严重脱销。
汽车运输专用车辆能提高运输生产率，降低运输成本，减少劳动消耗、缩短装卸时间、实现最佳经济效益。
例如自卸汽车减少了装卸劳动力，液罐运输车自行装卸油液，洒水车具有自动加水、喷洒道路冲洗水沟的功能，混凝土搅拌车具有拌搅水泥石沙和将混凝土运输到建筑工地的功能。
普通型汽车是不可能完成这些功能的。
汽车运输专用车辆具有专门的防护设备对于一些易燃、易爆、易腐蚀、有毒等化学物质必须使用专用车辆来运输，普通型汽车是难以胜任这些物质的运输工作。
除公路运输外，对石油勘探、市政工程、环保卫生、消防、机场、医疗、建筑等野需要专用汽车运输。
由于专用车辆具有一些普通型汽车不能比拟的功能，近年来，世界各国都大力发展专用汽车，致力于专用车辆的研究，以扩大汽车的使用范围。
根据统计资料介绍，美国专用汽车的产量占汽车产量的58%，9t～11.8t的中性汽车的保有量中，专用汽车占2/3以上。
日本专用车辆的保有量占中型货车的50%以上。
德国对专用车辆的需求量越来越大，不仅生产有工业、农业、林业、食品、市政等专用车辆，还生产有住宅式汽车、野外生活豪华型专用客车。
机械设计外文文献翻译、中英文翻译
机械设计外文文献翻译、中英文翻译unavailable。
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they can be corrected early on in the design process。
机械毕业设计英文外文翻译595专用汽车的发展状况
机械毕业设计英文外文翻译595专用汽车的发展状况The Development Status of Special Purpose VehiclesAbstract:With the rapid development of China's economy, the demandfor special purpose vehicles has increased significantly. Special purpose vehicles are essential for transportation, rescue operations, construction projects, and other specialized tasks. This paper aims to analyze the current development status of special purpose vehicles in China. It discusses the development history, industry size, key players, and future trends of the special purpose vehicle market.1. IntroductionSpecial purpose vehicles refer to vehicles that are specifically designed and manufactured for specific tasks or industries. They are different from regular passenger vehicles and trucks, as they are tailored to meet specific requirements. Special purpose vehicles include but are not limited to fire trucks, ambulances, dump trucks, concrete mixers, and aerial work platforms. The development of special purpose vehicles can be considered as an important indicator of a country's economic and industrial development.2. Development History3. Industry Size4. Key Players5. Future TrendsThe future of the special purpose vehicle market in China looks promising. As the country continues to develop and invest in infrastructure projects, the demand for special purpose vehicles will continue to rise. Additionally, with the advancement of technology, there will be a growing emphasis on environmental-friendly and energy-efficient vehicles. This will drive the development of electric and hybrid special purpose vehicles.Conclusion:。
机械毕业设计英文外文翻译595专用汽车的发展状况
附录1专用汽车的发展状况国外专用汽车产品的发展趋势专用汽车重型化趋势近年来，国外专用汽车的产量明显以重型居多，其原因主要是重型专用汽车经济效益好喝重型车功率大、强度高、有中、小型专用车无法替代的优点。
随着物流的庞大和公路的高级化，以及特殊作业的需要，重型专用汽车在国外得到迅速发展。
如德国的散装水泥车吨位均在15t以上；比例时莫尔公司今年花费相当大的人力、物力从事50~70t的大型挂车用牵引车的研究和生产。
比例时的大型粉罐车也已进行系列化生产，装载容积为30~60m。
散装水泥车的系列化趋势为了提高散装水泥车的卸料能力，国外进行了卓有成效的流态化元件研究，使卸料速度达到 1.5~1.8t/min（国产散装水汽车现行指标是1.0~1.3m/min），为提高远距离散运经济效益，散装水泥车的列车化正在成为今后的发展趋势。
据报道，澳大利亚的公路运输已普遍使用拖带双节挂车、甚至三节挂车的汽车列车。
1994年，澳大利亚一家挂车制造厂使用麦克（MACK）8×4牵引车，拖挂29节挂车，列车总长429m，有效质量500t，- 1发动机功率3657kW，每节挂车均为三轴式，双轴结构前转向架和三联式后轴。
一车多用化的趋势为提高专用汽车的适应性，以满足各种特殊需要，有趋势表明国外正在谋求专用汽车的一车多用化，使专用车功能由单一向多功能发展，如1990年如本昭和飞机公司退出了多用途厢式专用汽车，该车车厢为二重结构设计，装备了散装货物用的传送带，既能一般货运又可运输散装物料。
专用底盘专业化趋势日本丰田等大汽车公司的专用的盘均已实现系列化、专业化生产。
近年来，国外不少汽车厂专门从事专用汽车底盘生产，尤其重视专用底盘的系列化专业化生产、满足专用车的特殊需要。
我国专用汽车的发展趋势集团化发展趋势明显80年代初期开始，汽车行业经历了“六五”、“七五”十年发展已基本形成“三大、三小、两微”、“四轻、二中、三重”基本型汽车生产基地的格局，由分散走向集中、联合、集团化。
机械毕业设计英文外文翻译115电动平衡叉车 - 副本
附录ATray selection and with the shelves, forklift matchFirst, the selected tray Size:When used plastic pallets, according to the requirements of the project, the selected size will be different.1. First, consider the specifications and packaging of goods placed in the plastic tray method. For example: the European standard turnover box size is 600 * 400mm, 1200 * 1000mm pallet in place a layer of 5 in 1200 * 800mm layer placed on the tray 4, the general stacking 5 layers.2. Consider the pallet loading tools (such as containers, trucks, etc.). For example: If you are working round-trip or one-time use, you need to give priority to the width of 2300mm of integrated container shipping, for 1200 * 1000mm pallet, length 1200mm and width 1000mm to use a combination of place, must be selected to enter the fork 4. The tray on the 1200 * 800mm, 800mm width direction with two side by side. The pallet of 1100 * 1100mm width by 1100mm, placed 2, 2, or 4 to enter the fork into the fork can be.3. If used in the warehouse shelves, shelves to consider the size of width and depth, usually select the shelves each placed two trays of each cargo space, and allow access to the space of about 200mm. In depth directionas far as possible to give large size, this does not produce plastic pallets carrying capacity of the stringent requirements in order to save procurement costs.4. If the use of automated warehouse shelves, in addition to meet the above requirements, but also take into account the slip coefficient of the tray, the tray bottom with transmission equipment and chain, into the fork height, carrying capacity on the shelves, permanent deformation, length of surface deflection, the position of bar coding and RFID chips placed on other factors.5. Use plastic trays should also consider the size of generality, the size of the domestic common international standard for the 1210, 1208 European standard and T11 Japanese standard tray.Second, the choice of single and double-sided:1. Single use plastic pallets only one side, the surface grid of two peace-plate, the bottom of Sichuan fonts, font, or nine square field pad feet, according to carrying capacity and the use of different occasions into shelf series, standard series and ultra-light series of three standards.2. Sided plastic tray that the same structure on both sides of the tray, the surface grid plate of peace are two sides to exchange used, based on carrying capacity and the use of different occasions, the shelves are divided into two series and standard series standards.3. Use double-sided tray or trays should be based on the appropriatestorage, loading and unloading equipment and state (such as the library type, rack type, stacking or placing the state, etc.) to determine.4. For the small footprint of the ASRS or high shelves, or electric stacker forklift to move vertically oriented occasion, single-sided double-sided shelf series shelf series of trays and trays can be chosen.5. If the three-dimensional library or load up on the shelves of 1T, but there is no ceiling shelves, the proposed shelf tray with built-in pipe. Steel structure steel tray built an effective solution to the product on the shelf load the greater the greater the weight, the old problem of high cost, more importantly, about the use of square steel tube wall thickness of 2mm rigid, reaching the shelves (ASRS) are horizontal and vertical deflection ≤ 10mm stringent requirements, while reducing the permanent deformation and reduce costs.6. For the area, mainly the large and the level of the occasion, if the manual handling hydraulic pallet truck is suitable for use single-sided tray. For stacking of goods to the bottom of the tray above and below the cargo coincide, the swastika with the end of double-sided tray or tray-type side is better. If using self-moving motorized pallet trucks are suitable for articles not connected with the bottom of the nine feet single tray.Third, the load requirements1. Dynamic load refers to the use of electric forklift or a manual hydraulicpallet truck can lift the maximum weight allowed. General shelf tray to load-bearing 1.5T-2T, the standard load-bearing pallet can 1T, lightweight tray dynamic load 0.5T.2. Static load refers to the stacking, the bottom of the plastic tray can bear maximum weight. General shelf tray to load-bearing 6T-8T, the standard load-bearing pallet can 4T, lightweight tray static 1T.3. Shelf load refers to the plastic tray packaging on the shelves when the maximum allowable weight. Must pay attention to dynamic load, static load, load library shelf load and establish the difference between carrying capacity and shelves of different structures, closely related to ambient temperature and storage period. General heavy trays on a shelf in load-bearing beams 0.7T-1T, standard tray loading 0.4T-0.6T.4. Shelf load permanent deformation of the plastic tray and deflection have certain requirements, national standards for the maximum deflection 30mm, but this was partial width. We recommend using the deflection on the shelf no more than 20mm of plastic pallets. If the automatic warehouse, the requirements of the degree of deflection even more stringent, generally require less than 10mm. Cheng Machinery silver mesh)附录B电动平衡叉车是以直流电源（电瓶）为动力的装卸及搬运车辆。
机械工程毕业设计外文翻译
毕业设计论文外文资料原文及译文学院：机电工程学院专业：机械设计制造及其自动化班级：学号：姓名：Mechanical engineering1.The porfile of mechanical engineeringEngingeering is a branch of mechanical engineerig,it studies mechanical and power generation especially power and movement.2.The history of mechanical engineering18th century later periods,the steam engine invention has provided a main power fountainhead for the industrial revolution,enormously impelled each kind of mechznical biting.Thus,an important branch of a new Engineering – separated from the civil engineering tools and machines on the branch-developed together with Birmingham and the establishment of the Associantion of Mechanical Engineers in 1847 had been officially recognized.The mechanical engineering already mainly used in by trial and error method mechanic application technological development into professional engineer the scientific method of which in the research,the design and the realm of production used .From the most broad perspective,the demend continuously to enhance the efficiencey of mechanical engineers improve the quality ofwork,and asked him to accept the history of the high degree of education and training.Machine operation to stress not only economic but also infrastructure costs to an absolute minimun.3.The field of mechanical engineeringThe commodity machinery development in the develop country,in the high level material life very great degree is decided each kind of which can realize in the mechanical engineering.Mechanical engineers unceasingly will invent the machine next life to produce the commodity,unceasingly will develop the accuracy and the complexity more and more high machine tools produces the machine.The main clues of the mechanical development is:In order to enhance the excellent in quality and reasonable in price produce to increase the precision as well as to reduce the production cost.This three requirements promoted the complex control system development.The most successful machine manufacture is its machine and the control system close fusion,whether such control system is essentially mechanical or electronic.The modernized car engin production transmission line(conveyer belt)is a series of complex productions craft mechanizationvery good example.The people are in the process of development in order to enable further automation of the production machinery ,the use of a computer to store and handle large volumes of data,the data is a multifunctional machine tools necessary for the production of spare parts.One of the objectives is to fully automated production workshop,three rotation,but only one officer per day to operate.The development of production for mechanical machinery must have adequate power supply.Steam engine first provided the heat to generate power using practical methods in the old human,wind and hydropower,an increase of engin .New mechanical engineering industry is one of the challenges faced by the initial increase thermal effciency and power,which is as big steam turbine and the development of joint steam boilers basically achieved.20th century,turbine generators to provide impetus has been sustained and rapid growth,while thermal efficiency is steady growth,and large power plants per kW capital consumption is also declining.Finally,mechanical engineers have nuclear energy.This requires the application of nuclear energy particularly high reliability and security,which requires solving many new rge power plants and the nuclear power plant control systems have become highly complex electroonics,fluid,electricity,water and mechanical parts networks All in all areas related to the mechanical engineers.Small internal combustion engine,both to the type (petrol and diesel machines)or rotary-type(gas turbines and Mong Kerr machine),as well as their broad application in the field of transport should also due to mechanical enginerrs.Throughout the transport,both in the air and space,or in the terrestrial and marine,mechanial engineers created a variety of equipment and power devices to their increasing cooperation with electrical engineers,especially in the development of appropration control systems.Mechanical engineers in the development of military weapons technology and civil war ,needs a similar,though its purpose is to enhance rather than destroy their productivity.However.War needs a lot of resources to make the area of techonlogy,many have a far-reaching development in peacetime efficiency.Jet aircraft and nuclear reactors are well known examples.The Biological engineering,mechanical engineering biotechnology is a relatively new and different areas,it provides for the replacement of the machine or increase thebody functions as well as for medical equipment.Artficial limbs have been developed and have such a strong movement and touch response function of the human body.In the development of artificial organ transplant is rapid,complex cardiac machines and similar equipment to enable increasingly complex surgery,and injuries and ill patients life functions can be sustained.Some enviromental control mechanical engineers through the initial efforts to drainage or irrigation pumping to the land and to mine and ventilation to control the human environment.Modern refrigeration and air-conditioning plant commonaly used reverse heat engine,where the heat from the engine from cold places to more external heat.Many mechanical engineering products,as well as other leading technology development city have side effects on the environment,producing noise,water and air pollution caused,destroyed land and landscape.Improve productivity and diver too fast in the commodity,that the renewable naturalforces keep pace.For mechanical engineers and others,environmental control is rapidly developing area,which includes a possible development and production of small quantities of pollutants machine sequnce,and the development of new equipment and teachnology has been to reduce and eliminate pollution.4.The role of mechanical engineeringThere are four generic mechanical engineers in common to the above all domains function.The 1st function is the understanding and the research mechanical science foundation.It includes the power and movement of the relationship dynamics For example,in the vibration and movement of the relationship;Automatic control;Study of the various forms of heart,energy,power relations between the thermodynamic;Fluidflows; Heat transfer; Lubricant;And material properties.The 2nd function will be conducts the research,the desing and the development,this function in turn attempts to carry on the essential change to satisfy current and the future needs.This not only calls for a clear understanding of mechanical science,and have to breakdown into basic elements of a complex system capacity.But also the need for synthetic and innovative inventions.The 3rd function is produces the product and the power,include plan,operation and maintenance.Its goal lies in the maintenance eitherenhances the enterprise or the organization longer-tern and survivabilaty prestige at the same time,produces the greatest value by the least investments and the consumption.The 4th function is mechanical engineer’s coordinated function,including the management,the consultation,as well as carries on the market marking in certain situation.In all these function,one kind unceasingly to use the science for a long time the method,but is not traditional or the intuition method tendency,this is a mechanical engineering skill aspect which unceasingly grows.These new rationalization means typical names include:The operations research,the engineering economics,the logical law problem analysis(is called PABLA) However,creativity is not rationalization.As in other areas,in mechanical engineering,to take unexpected and important way to bring about a new capacity,still has a personal,marked characteristice.5.The design of mechanical engineeringThe design of mechanical is the design has the mechanical property the thing or the system,such as:the instrument and the measuring appliance in very many situations,the machine design must use the knowledge of discipline the and so on mathematics,materials science and mechanics.Mechanical engineering desgin includeing all mechanical desgin,but it was a study,because it also includes all the branches of mechsnical engineering,such as thermodynamics all hydrodynamics in the basic disciplines needed,in the mechanical engineering design of the initial stude or mechanical design.Design stages.The entire desgin process from start to finish,in the process,a demand that is designed for it and decided to do the start.After a lot of repetition,the final meet this demand by the end of the design procees and the plan.Design considerations.Sometimes in a system is to decide which parts needs intensity parts of geometric shapesand size an important factor in this context that we must consider that the intensity is an important factor in the design.When we use expression design considerations,we design parts that may affect the entire system design features.In the circumstances specified in the design,usually for a series of such functions must be taken into account.Howeever,to correct purposes,we should recognize that,in many cases thedesign of important design considerations are not calculated or test can determine the components or systems.Especially students,wheen in need to make important decisions in the design and conduct of any operation that can not be the case,they are often confused.These are not special,they occur every day,imagine,for example,a medical laboratory in the mechanical design,from marketing perspective,people have high expectations from the strength and relevance of impression.Thick,and heavy parts installed together:to produce a solid impression machines.And sometimes machinery and spare parts from the design style is the point and not the other point of view.Our purpose is to make those you do not be misled to believe that every design decision will needreasonable mathematical methods.Manufacturing refers to the raw meterials into finished products in the enterprise.Create three distinct phases.They are:input,processing exprot.The first phase includes the production of all products in line with market needs essential.First there must be the demand for the product,the necessary materials,while also needs such as energy,time,human knowledge and technology resourcess .Finall,the need for funds to obtain all the other resources. Lose one stage after the second phase of the resources of the processes to be distributed.Processing of raw materials into finished products of these processes.To complete the design,based on the design,and then develop plans.Plan implemented through various production processes.Management of resources and processes to ensure efficiency and productivity.For example,we must carefully manage resources to ensure proper use of funds.Finally,people are talking about the product market was cast.Stage is the final stage of exporting finished or stage.Once finished just purchased,it must be delivered to the users.According to product performance,installation and may have to conduct further debugging in addition,some products,especially those very complex products User training is necessary.6.The processes of materials and maunfacturingHere said engineering materials into two main categories:metals and non-ferrous,high-performance alloys and power metals.Non-metallic futher divided into plastice,synthetic rubber,composite materials and ceramics.It said the productionproccess is divided into several major process,includingshape,forging,casting/ founding,heat treatment,fixed/connections ,measurement/ quality control and materal cutting.These processes can be further divide into each other’s craft.Various stages of the development of the manufacturing industry Over the years,the manufacturing process has four distinct stages of development, despite the overlap.These stages are:The first phase is artisanal,the second Phase is mechanization.The third phase is automation the forth Phase is integrated.When mankind initial processing of raw materials into finished products will be,they use manual processes.Each with their hands and what are the tools manuslly produced.This is totally integrated production take shape.A person needs indentification,collection materials,the design of a product to meet that demand,the production of such products and use it.From beginning to end,everything is focused on doing the work of the human ter in the industrial revolution introduced mechanized production process,people began to use machines to complete the work accomplished previously manual. This led to the specialization.Specialization in turn reduce the manufacture of integrated factors.In this stage of development,manufacturing workers can see their production as a whole represent a specific piece of the part of the production process.One can not say that their work is how to cope with the entire production process,or how they were loaded onto a production of parts finished.Development of manufacting processes is the next phase of the selection process automation.This is a computer-controlled machinery and processes.At this stage,automation island began to emerge in the workshop lane.Each island represents a clear production process or a group of processes.Although these automated isolated island within the island did raise the productivity of indivdual processes,but the overall productivity are often not change.This is because the island is not caught in other automated production process middle,but not synchronous with them .The ultimate result is the efficient working fast parked through automated processes,but is part of the stagnation in wages down,causing bottlenecks.To better understand this problem,you can imagine the traffic in the peak driving a red light from the red Service Department to the next scene. Occasionally you will find a lot less cars,more than being slow-moving vehicles,but the results can be found by thenext red light Brance.In short you real effect was to accelerate the speed of a red Department obstruction offset.If you and other drivers can change your speed and red light simultaneously.Will advance faster.Then,all cars will be consistent,sommth operation,the final everyone forward faster.In the workshop where the demand for stable synchronization of streamlined production,and promoted integration of manufacturing development.This is a still evolving technology.Fully integrated in the circumstances,is a computer-controllrd machinery and processing.integrated is completed through computer.For example in the preceding paragraph simulation problems,the computer will allow all road vehicles compatible with the change in red.So that everyone can steady traffic.Scientific analysis of movement,timing and mechanics of the disciplines is that it is composed of two pater:statics and dynamics.Statics analyzed static system that is in the system,the time is not taken into account,research and analysis over time and dynamics of the system change.Dynameics from the two componets.Euler in 1775 will be the first time two different branches: Rigid body movement studies can conveniently divided into two parts:geometric and mechanics.The first part is without taking into account the reasons for the downward movement study rigid body from a designated location to another point of the movement,and must use the formula to reflect the actual,the formula would determine the rigid body every point position. Therefore,this study only on the geometry and,more specifically,on the entities from excision.Obviously,the first part of the school and was part of a mechanical separation from the principles of dynamics to study movement,which is more than the two parts together into a lot easier.Dynamics of the two parts are subsequently divided into two separate disciplines,kinematic and dynamics,a study of movement and the movement strength.Therefore,the primary issue is the design of mechanical systems understand its kinematic.Kinematic studies movement,rather than a study of its impact.In a more precise kinematic studies position,displacement,rotation, speed,velocity and acceleration of disciplines,for esample,or planets orbiting research campaing is a paradigm.In the above quotation content should be pay attention that the content of the Euler dynamics into kinematic and rigid body dynamics is based on the assumptionthat they are based on research.In this very important basis to allow for the treatment of two separate disciplines.For soft body,soft body shape and even their own soft objects in the campaign depends on the role of power in their possession.In such cases,should also study the power and movement,and therefore to a large extent the analysis of the increased complexity.Fortunately, despite the real machine parts may be involved are more or less the design of machines,usually with heavy material designed to bend down to the lowest parts.Therefore,when the kinematic analysis of the performance of machines,it is often assumed that bend is negligible,spare parts are hard,but when the load is known,in the end analysis engine,re-engineering parts to confirm this assnmption.机械工程1.机械工程简介机械工程是工程学的一个分支，它研究机械和动力的产，尤其是力和动力。
(完整版)机械毕业设计 外文翻译
内蒙古科技大学本科生毕业设计外文翻译学生姓名：武新伟专业：过程装备与控制工程班级：装备09-1 班指导教师：李胜（王昌）高工不同的行为批次和半连续反应器的两个化学反应的比较研究M.D. Grau a,1, J.M. Nougués b,2, L. Puigjaner b,*,2a矿业及天然资源工程系，曼雷沙大学，加泰罗尼亚理工大学,AV.西班牙曼雷沙61-73基地，08240 .b巴塞罗那工业工程学院，加泰罗尼亚理工大学化学工程系，AV.西班牙巴塞罗那，对角线647，08028.2001年10月收到，2002年2月19日发表摘要：基于不同的行为的两个反应，批处理和半间歇反应器性能之间的比较研究已经进行了在玻璃夹套设置与测量5升的反应器中，数据采集和控制系统。
所选择的反应是酸 - 碱反应（乙酸乙酯皂化反应），和一个具有高的反应热（硫代硫酸钠，过氧化反应）的氧化 - 还原反应。
甲第一差值的方法中，用于建立的动力学方程。
对于使用的酸 - 碱反应的等温方法，根据该溶液的电导率，用于氧化反应的温度的测量的基础上使用的绝热方法。
此工作的重点在于得到的物种的浓度，在反应器中，通过实验测量与不同的传感器（pH，温度，等）所需要的值，以得到的浓度分布。
对于酸- 碱反应，它可以转换成浓度值的反应溶液的pH值测量。
在氧化反应的情况下，通过测量唯一的反应器的温度为绝热的批处理模式下的操作，和在半间歇法的操作模式通过仿真得到的浓度分布。
以前被验证实验获得的温度分布的数学模型。
关键词:批处理和半间歇反应器；模型；反应动力学命名法a：化学计量系数反应物AAi：内传热面积（米2）A0：以外的传热面积（米2）B：反应物B的化学计量系数c A ：反应物的浓度（NaOH或H 2 O 2）（千摩尔米-3）c A0：初始反应物的浓度甲（千摩尔米-3）c A1：初始反应物的浓度在坦克（千摩尔米-3）c B：反应物B的浓度（千摩尔米-3）c B0：反应物B的初始浓度（千摩尔米-3）c B1：罐中反应物B的初始浓度（千摩尔米-3）c P：浓度的产品（千摩尔米-3）C J：护套的流体的热容量（千焦耳千克-1 K -1）C P：的反应物的热容量（千焦耳千克-1 K -1）C M：的壁的热容量（千焦耳千克-1K -1）Ea：活化能（千焦耳千摩尔-1）F W：护套的流体流（米3 s-1）F0：添加流量（米3s-1）[10]，但反应物和产物的浓度的演变没有调查，这是非常重要的是要优化运行性能，因为它已经指出，Hugo[11] 等人。
机械毕业设计英文外文翻译589专题 精密校直机的控制系统
专题精密校直机的控制系统一、概述机械、汽车、电机等行业大量使用轴类、杆类零件，这些零件的原材料在粗加工火热处理等过程中不可避免地会出现弯曲变形，如果不进行校直处理会直接影响工件的后序加工和使用，甚至可能出现相当数量的废品。
所以为了能获得下道工序所允许的最小切削量或通过精密校直保证工件达到严格的最终设计公差要求，校直机成了工件热处理后不可缺少的关键设备。
在传统工艺中，多数厂家选用手动压力机，校直量难以控制，效率低下，难以满足校直要求；而自动校直是一种先进的生产制造工艺，近年来随着我国工业整体技术水平和技术要求的提高，该工艺被越来越广泛地应用于机械、汽车、电机等行业中。
自动校直技术通过数控精密校直液压机（简称精校机）完成对轴、管、棒等类零件的校直，是一种先进制造技术，是机械加工过程中保证产品质量的重要工序，广泛应用于汽车、拖拉机、工程机械、机床、纺织机械等机械制造行业。
发达国家对该项技术的研究起步较早，已开发出具有本国特色的自动精校机产品。
而我国在这一领域才刚刚起步，目前国内应用的大部分精校机都从国外引进。
随着我国机械工业的发展，对机械产品质量的要求不断提高，此项技术的重要性日益显现出来，迫切需要自动校直技术及其成套设备，实现对轴类零件的精密校直，以提高轴类零件的加工精度。
二、BUM系列轴类自动校直机一）设备说明该产品适用范围包括：转向齿条、凸轮轴、曲轴、半轴、齿轮轴、电机轴、减震器杆、活塞杆、车桥壳等轴杆类零件。
该系列产品在消化吸收国外技术的同时，针对国内客户情况，在校直原理、测量方式、人机交互、特殊工件处理方面都作了大量创新设计。
普通零部件国内设计加工，关键器件选用的是日本、韩国、德国等国家著名公司的进口产品，从而保证了利用国内产品价格拥有世界级自动校直机的整体品质。
该系列产品主要特性：1、高可靠性、高精度的测量系统，测量精度±5μm、显示分辨率1μm ；2、修正量的自适应调整系统，精密液压控制，自动分析计算修正量对工件缺陷（中心偏心、椭圆、毛刺等）的特殊处理，解决了假性弯曲的问题；3、先进的WINDOWS测量系统，友好的人机对话界面，较好地实现了操作者与设备的人机交互；4、简洁方便的工件夹持定位装置，用户可快速方便地调整工装，满足不同工件生产要求；5、声发射装置可供选择，可检测出工件裂纹缺陷；6、高效生产效率，满足大批量生产要求7、可存储多种不同工件参数，满足不同种类产品校直需要二）主要部分介绍1、液压控制系统泵站、液压阀组、执行油缸，液压控制回路等组成了校直机的液压系统。
机械设计制造及其自动化毕业论文中英文资料外文翻译
机械设计创造及其自动化毕业论文外文文献翻译INTEGRATION OF MACHINERY译文题目专业机械设计创造及其自动化外文资料翻译INTEGRATION OF MACHINERY（From ELECTRICAL AND MACHINERY INDUSTRY）ABSTRACTMachinery was the modern science and technology development inevitable result, this article has summarized the integration of machinery technology basic outline and the development background .Summarized the domestic and foreign integration of machinery technology present situation, has analyzed the integration of machinery technology trend of development.Key word： integration of machinery ，technology， present situation ，product t，echnique of manufacture ，trend of development0. Introduction modern science and technology unceasing development, impelled different discipline intersecting enormously with the seepage, has caused the project domain technological revolution and the transformation .In mechanical engineering domain, because the microelectronic technology and the computer technology rapid development and forms to the mechanical industry seepage the integration of machinery, caused the mechanical industry the technical structure, the product organization, the function and the constitution, the production method and the management systemof by machinery for the characteristic integration ofdevelopment phase.1. Integration of machinery outline integration of machinery is refers in the organization new owner function, the power function, in the information processing function and the control function introduces the electronic technology, unifies the system the mechanism and the computerization design and the software which constitutes always to call. The integration of machinery development also has become one to have until now own system new discipline, not only develops along with the science and technology, but also entrusts with the new content .But its basic characteristic may summarize is: The integration of machinery is embarks from the system viewpoint, synthesis community technologies and so on utilization mechanical technology, microelectronic technology, automatic control technology, computer technology, information technology, sensing observation and control technology, electric power electronic technology, connection technology, information conversion technology as well as software programming technology, according to the system function goal and the optimized organization goal, reasonable disposition and the layout various functions unit, in multi-purpose, high grade, redundant reliable, in the low energy consumption significance realize the specific function value, and causes the overall system optimization the systems engineering technology .From this produces functional system, then becomes an integration of machinery systematic or the integration of machinery product. Therefore, of coveringtechnology is based on the above community technology organic fusion one kind of comprehensive technology, but is not mechanical technical, the microelectronic technology as well as other new technical simple combination, pieces together .This is the integration of machinery and the machinery adds the machinery electrification which the electricity forms in the concept basic difference .The mechanical engineering technology has the merely technical to develop the machinery electrification, still was the traditional machinery, its main function still was replaces with the enlargement physical strength .But after develops the integration of machinery, micro electron installment besides may substitute for certain mechanical parts the original function, but also can entrust with many new functions,like the automatic detection, the automatic reduction information, demonstrate the record, the automatic control and the control automatic diagnosis and the protection automatically and so on .Not only namely the integration of machinery product is human's hand and body extending, human's sense organ and the brains look, has the intellectualized characteristic is the integration of machinery and the machinery electrification distinguishes in the function essence.2. Integration of machinery development condition integration of machinery development may divide into 3 stages roughly.20th century 60's before for the first stage, this stage is called the initial stage .In this time, the people determination not on own initiative uses the electronic technology the preliminary achievement to consummate the mechanical product the performance .Specially in Second World War period, the war has stimulated the mechanical product and the electronic technology union, these mechanical and electrical union military technology, postwar transfers civilly, to postwar economical restoration positive function .Developed and the development at that time generally speaking also is at the spontaneouscondition .Because at that time the electronic technology development not yet achieved certain level, mechanical technical and electronic technology union also not impossible widespread and thorough development, already developed the product was also unable to promote massively. The 20th century 70~80 ages for the second stage, may be called the vigorous development stage .This time, the computer technology, the control technology, the communication development, has laid the technology base for the integration of machinery development . Large-scale, ultra large scale integrated circuit and microcomputer swift and violent development, has provided the full material base for the integration of machinery development .This time characteristic is :①A mechatronics word first generally is accepted in Japan, probably obtains the quite widespread acknowledgment to 1980s last stages in the worldwide scale ;②The integration of machinery technology and the product obtained the enormous development ;③The various countries start to the integration of machinery technology and the product give the very big attention and the support. 1990s later periods, started the integration of machinery technology the new stagewhich makes great strides forward to the intellectualized direction, the integration of machinery enters the thorough development time .At the same time, optics, the communication and so on entered the integration of machinery, processes the technology also zhan to appear tiny in the integration of machinery the foot, appeared the light integration of machinery and the micro integration of machinery and so on the new branch; On the other hand to the integration of machinery system modeling design, the analysis and the integrated method, the integration of machinery discipline system and the trend of development has all conducted the thorough research .At the same time, because the hugeprogress which domains and so on artificial intelligence technology, neural network technology and optical fiber technology obtain, opened the development vast world for the integration of machinery technology .These research, will urge the integration of machinery further to establish the integrity the foundation and forms the integrity gradually the scientific system. Our country is only then starts from the beginning of 1980s in this aspect to study with the application .The State Councilsummary had considered fully on international the influence which and possibly brought from this about the integration of machinery technology developmenttrend .Many universities, colleges and institutes, the development facility and some large and middle scale enterprises have done the massive work to this technical development and the application, does not yield certain result, but and so on the advanced countries compared with Japan still has the suitable disparity.3. Integration of machinery trend of development integrations of machinery are the collection machinery, the electron, optics, the control, the computer, the information and so on the multi-disciplinary overlapping syntheses, its development and the progress rely on and promote the correlation technology development and the progress .Therefore, the integration of machinery main development direction is as follows:3.1 Intellectualized intellectualizations are 21st century integration of machinery technological development important development directions .Theartificial intelligence obtains day by day in the integration of machinery constructor's research takes, the robot and the numerical control engine bedis to the machine behavior description, is in the control theory foundation, the absorption artificial intelligence, the operations research, the computer science, the fuzzy mathematics, the psychology, the physiology and the chaos dynamics and so on the new thought, the new method, simulate the human intelligence, enable it to have abilities and so on judgment inference, logical thinking, independent decision-making, obtains the higher control goal in order to .Indeed, enable the integration of machinery product to have with the human identical intelligence, is not impossible, also is nonessential .But, the high performance, the high speed microprocessor enable the integration of machinery product to have preliminary intelligent or human's partial intelligences, then is completely possible and essential.In the modern manufacture process, the information has become the control manufacture industry the determining factor, moreover is the most active actuation factor .Enhances the manufacture system information-handling capacity to become the modern manufacture science development a key point .As a result of the manufacture system information organization and structure multi-level, makes the information the gain, the integration and the fusion presents draws up the character, information measure multi-dimensional, as well as information organization's multi-level .In the manufacture information structural model, manufacture information uniform restraint, dissemination processing and magnanimous data aspects and so on manufacture knowledge library management, all also wait for further break through.Each kind of artificial intelligence tool and the computation intelligence method promoted the manufacture intelligence development in the manufacture widespread application .A kind based on the biological evolution algorithm computation intelligent agent, in includes thescheduling problem in the combination optimization solution area of technology, receives the more and more universal attention, hopefully completes the combination optimization question when the manufacture the solution speed and the solution precision aspect breaks through the question scale in pairs the restriction .The manufacture intelligence also displays in: The intelligent dispatch, the intelligent design, the intelligent processing, the robot study, the intelligent control, the intelligent craft plan, the intelligent diagnosis and so on are various These question key breakthrough, may form the product innovation the basic research system. Between 2 modern mechanical engineering front science different science overlapping fusion will have the new science accumulation, the economical development and society's progress has had the new request and the expectation to the science and technology, thus will form the front science .The front science also has solved and between the solution scientific question border area .The front science has the obvious time domain, the domain and the dynamic characteristic .The project front science distinguished in the general basic science important characteristic is it has covered the key science and technology question which the project actual appeared.Manufacture system is a complex large-scale system, for satisfies the manufacture system agility, the fast response and fast reorganization ability, must profit from the information science, the life sciences and the social sciences and so on the multi-disciplinary research results, the exploration manufacture system new architecture, the manufacture pattern and the manufacture system effective operational mechanism .Makes the system optimization the organizational structure and the good movement condition is makes the system modeling , the simulation and the optimized essential target .Not only the manufacture system new architecture to makes the enterprise the agility and may reorganize ability to the demand response ability to have the vital significance, moreover to made the enterprise first floor production equipment the flexibility and may dynamic reorganization ability set a higher request .The biological manufacture view more and more many is introduced the manufacture system, satisfies the manufacture system new request.The study organizes and circulates method and technique of complicated system from the biological phenomenon, is a valid exit which will solve many hard nut to cracks that manufacturing industry face from now on currently .Imitating to living what manufacturing point is mimicry living creature organ of from the organization, from match more, from growth with from evolution etc. function structure and circulate mode of a kind of manufacturing system and manufacturing process.The manufacturing drives in the mechanism under, continuously by one's own perfect raise on organizing structure and circulating mode and thus to adapt the process of[with] ability for the environment .For from descend but the last product proceed together a design and make a craft rules the auto of the distance born, produce system of dynamic state reorganization and product and manufacturing the system tend automatically excellent provided theories foundation and carry out acondition .Imitate to living a manufacturing to belong to manufacturing science and life science of"the far good luck is miscellaneous to hand over", it will produce to the manufacturing industry for 21 centuries huge of influence .机电一体化摘要机电一体化是现代科学技术发展的必然结果,本文简述了机电一体化技术的基本概要和发展背景。
机械专业外文翻译(中英文翻译)
机械专业外文翻译（中英文翻译）第1页Among the methods of material conveying employed，belt conveyorsplaya very important part in the reliable carrying of material over longdistances at competitive cost．Conveyor systems have become larger and morecomplex and drive systems have also been going through a process of evolutionand will continue to do so．Nowadays，bigger belts require more power and havebrought the need for larger individual drives as well as multiple drives suchas 3 drives of 750 kW for one belt(this is the case for the conveyor drivesin Chengzhuang Mine)．The ability to control drive acceleration torque iscritical to belt conveyors’ performance．An efficient drive system should beable to provide smooth，soft starts while maintaining belt tensions withinthe specified safe limits．For load sharing on multiple drives．torque andspeed control are also important considerations in the drive system’s design.Due to the advances in conveyor drive control technology，at present many morereliable．Cost-effective and performance-driven conveyor drive systems[1]covering a wide range of power are available for customers’ choices. Full-voltage starters．With a full-voltage starter design，the conveyor head shaft is direct-coupled to the motor through the gear drive．Direct full-voltage startersare adequate for relatively low-power, simple-profile conveyors．With direct fu11-voltage starters．no control is provided for various conveyor loadsand．depending on the ratio between fu11- and no-1oad power requirements，empty starting times can be three or four times faster than full load．The maintenance-free starting system is simple，low-cost and very reliable．However, they cannot control starting torque and maximum stall torque；therefore．they are第2页 limited to the low-power, simple-profile conveyor belt drives．Reduced-voltage starters．As conveyor power requirements increase，controlling the applied motor torque during the acceleration period becomes increasinglyimportant．Because motor torque 1s a function of voltage，motor voltage must be controlled．This can be achieved through reduced-voltage starters by employinga silicon controlled rectifier(SCR)．A common starting method with SCRreduced-voltage starters is to apply low voltage initially to takeup conveyorbelt slack．and then to apply a timed linear ramp up to full voltage and beltspeed．However, this starting method will not produce constant conveyor beltacceleration．When acceleration is complete．the SCRs, which control the applied voltage to the electric motor． are locked in full conduction, providing fu11-linevoltage to the motor．Motors with higher torque and pull—uptorque，can provide better starting torque when combined with the SCR starters, which are availablein sizes up to 750 KW．Wound rotor induction motors．Wound rotor induction motors are connecteddirectly to the drive system reducer and are a modifiedconfiguration of a standardAC induction motor．By inserting resistance in series with the motor’s rotor windings．the modified motor control system controlsmotor torque．For conveyor starting，resistance is placed in series with the rotor for low initial torque．As the conveyor accelerates，the resistance is reduced slowly to maintain a constantacceleration torque．On multiple-drive systems．an external slip resistor may beleft in series with the rotor windings to aid in load sharing．The motor systems have a relatively simple design．However, the control systems for these can behighly complex，because they are based on computer control of the resistanceswitching．Today，the majority of control systems are custom designed to meet aconveyor system’s particular specifications．Wound rotor motors are appropriatefor systems requiring more than 400 kW ．DC motor．DC motors．available from a fraction of thousands of kW ，are designed to deliver constant torque below base speed and constant kW above base speed tothe maximum allowable revolutions per minute(r/min)．with the majority of conveyordrives, a DC shunt wound motor is used．Wherein the motor’srotating armature is第3页 connected externally．The most common technology for controlling DC drives is aSCR device． which allows for continual variable-speed operation．The DC drive system is mechanically simple, but can include complex custom-designed electronicsto monitor and control the complete system．This system option is expensive incomparison to other soft-start systems．but it is a reliable, cost-effective drivein applications in which torque,1oad sharing and variable speed are primaryconsiderations．DC motors generally are used with higher-power conveyors，including complex profile conveyors with multiple-drive systems，booster tripper systems needing belt tension control and conveyors requiring a wide variable-speed range．Hydrokinetic couplings，commonly referred to as fluid couplings．are composed of three basic elements; the driven impeller, which acts as a centrifugal pump；the driving hydraulic turbine known as the runner and a casing that encloses thetwo power components．Hydraulic fluid is pumped from the driven impeller to thedriving runner, producing torque at the driven shaft．Because circulating hydraulicfluid produces the torque and speed，no mechanical connection is required betweenthe driving and driven shafts．The power produced by this coupling is based onthe circulated fluid’s amount and density and the torque in proportion to inputspeed．Because the pumping action within the fluid coupling depends on centrifugalforces．the output speed is less than the input speed．Referred to as slip．this normally is between l% and 3%．Basic hydrokinetic couplings are available inconfigurations from fractional to several thousand kW ．Fixed-fill fluid couplings．Fixed-fill fluid couplings are the most commonlyused soft-start devices for conveyors with simpler belt profiles and limitedconvex/concave sections．They are relativelysimple,1ow-cost,reliable,maintenance free devices that provide excellent softstarting results to the majority of belt conveyors in use today．Variable-fill drain couplings．Drainable-fluid couplings work on the sameprinciple as fixed-fill couplings．The coupling’s impellers are mounted on the ACmotor and the runners on the driven reducer high-speed shaft．Housing mounted to the drive base encloses the working circuit．The coupling’s rotating casing contains第4页 bleed-off orifices that continually allow fluid to exit the working circuit intoa separate hydraulic reservoir．Oil from the reservoir is pumped through a heatexchanger to a solenoid-operated hydraulic valve that controls the filling of thefluid coupling．To control the starting torque of a single-drive conveyor system，the AC motor current must be monitored to provide feedback to the solenoid controlvalve．Variable fill drain couplings are used in medium to high-kW conveyor systemsand are available in sizes up to thousands of kW ．The drives can be mechanicallycomplex and depending on the control parameters．the system can be electronicallyintricate．The drive system cost is medium to high, depending upon size specified．Hydrokinetic scoop control drive．The scoop control fluid coupling consistsof the three standard fluid coupling components：a driven impeller, a driving runnerand a casing that encloses the working circuit．The casing is fitted with fixedorifices that bleed a predetermined amount of fluid into a reservoir．When the scoop tube is fully extended into the reservoir, the coupling is l00 percentfilled．The scoop tube, extending outside the fluid coupling，is positioned using an electric actuator to engage the tube from the fully retracted to the fullyengaged position．This control provides reasonably smooth acceleration rates．to but the computer-based control system is very complex．Scoop control couplings are applied on conveyors requiring single or multiple drives from l50 kW to 750kW.Variable frequency control is also one of the direct drive methods．The emphasizing discussion about it here is because that it has so uniquecharacteristic and so good performance compared with other driving methods forbelt conveyor． VFC devices Provide variable frequency and voltageto the inductionmotor, resulting in an excellent starting torque and acceleration rate for beltconveyor drives．VFC drives．available from fractional to several thousand(kW ),are electronic controllers that rectify AC line power to DC and，through an inverter, convert DC back to AC with frequency and voltage contro1．VFC drives adopt vector control or direct torquecontrol(DTC)technology，and can adopt different operating speeds according to different loads．VFC drives can make starting or stalling第5页 according to any given S-curves．realizing the automatic track for starting orstalling curves．VFC drives provide excellent speed and torque control for startingconveyor belts．and can also be designed to provide load sharing for multipledrives．easily VFC controllers are frequently installed on lower-powered conveyordrives，but when used at the range of medium-high voltage in the past．the structure of VFC controllers becomes very complicated due to the limitation of voltage ratingof power semiconductor devices，the combination of medium-high voltage drives andvariable speed is often solved with low-voltage inverters usingstep-uptransformer at the output，or with multiple low-voltage inverters connected inseries．Three-level voltage-fed PWM converter systems are recently showingincreasing popularity for multi-megawatt industrial driveapplications becauseof easy voltage sharing between the series devices and improved harmonic qualityat the output compared to two-level converter systems With simple series connectionof devices．This kind of VFC system with three 750 kW /2．3kV inverters has been successfully installed in ChengZhuang Mine for one 2．7-km long belt conveyordriving system in following the principle of three-level inverterwill be discussedin detail．Three-level voltage-fed inverters have recently become more and more popularfor higher power drive applications because of their easy voltage sharingfeatures．1ower dv/dt per switching for each of the devices，and superior harmonic quality at the output．The availability of HV-IGBTs has led to the design of anew range of medium-high voltage inverter using three-level NPC topology．This kind of inverter can realize a whole range with a voltagerating from 2．3 kV to 4．1 6 kV Series connection of HV-IGBT modules is used in the 3．3 kV and 4．1[2,3]6 kV devices．The 2．3 kV inverters need only one HV-IGBT per switch.To meet the demands for medium voltage applications．a three-level neutral point clamped inverter realizes the power section．In comparison to a two-levelinverter．the NPC inverter offers the benefit that three voltage levels can besupplied to the output terminals，so for the same output current quality，only第6页1/4 of the switching frequency is necessary．Moreover the voltage ratings of theswitches in NPC inverter topology will be reduced to 1/2．and the additional transient voltage stress on the motor can also be reduced to 1/2 compared to thatof a two-level inverter．The switching states of a three-level inverter are summarized in Table 1．U．V and W denote each of the three phases respectively；P N and O are the dc bus points．The phase U，for example，is in stateP(positive bus voltage)when theswitches S and S are closed，whereas it is in state N (negative bus voltage) 1u2uwhen the switches S and S are closed．At neutral point clamping，the phase is 3u4uin O state when either Sor S conducts depending on positive or negative phase 2u 3ucurrent polarity，respectively．For neutral point voltage balancing，the average current injected at O should be zero．For standard applications．a l2-pulse diode rectifier feeds the divided DC-linkcapacitor．This topology introduces low harmonics on the line side．For even higher requirements a 24-pulse diode rectifier can be used as an input converter．For more advanced applications where regeneration capability is necessary, an activefront．end converter can replace the diode rectifier, using the same structureas the inverter．Motor Contro1．Motor control of induction machines is realized by using a rotorflux．oriented vector controller．Fig．2 shows the block diagram of indirect vector controlled drive thatincorporates both constant torque and high speed field-weakening regions wherethe PW M modulator was used．In this figure，the command flux is generated as function of speed．The feedback speed is added with the feed forward slip commandsignal . the resulting frequency signal is integrated and then the unit vectorsignals(cos and sin )are generated．The vector rotator generates the voltageand angle commands for the PW M as shown．PWM Modulator．The demanded voltage vector is generated using an elaborate第7页 PWM modulator．The modulator extends the concepts of space-vector modulation tothe three-level inverter．The operation can be explained by starting from aregularly sampled sine-triangle comparison from two-level inverter．Instead of using one set of reference waveforms and one triangle defining the switchingfrequency， the three-level modulator uses two sets of reference waveforms U and r1U and just one triangle．Thus, each switching transition is used in an optimal r2way so that several objectives are reached at the same time．Very low harmonics are generated．The switching frequency is low and thusswitching losses are minimized．As in a two-level inverter, a zero-sequencecomponent can be added to each set of reference waveform s in order to maximizethe fundamental voltage component．As an additional degree of freedom，the position of the reference waveform s within the triangle can be changed．This can be used for current balance in the two halves of the DC-1ink．After Successful installation of three 750 kW /2．3 kV three-level invertersfor one 2．7 km long belt conveyor driving system in Chengzhuang Mine．The performance of the whole VFC system was tested．Fig．3 is taken from the test，which shows the excellent characteristic of the belt conveyor driving system withVFC controller．Fig．3 includes four curves．The curve 1 shows the belt tension．From the curve it can be find that the fluctuation range of the belt tension is very smal1．Curve 2 and curve 3 indicate current and torque separately．Curve 4 shows the velocityof the controlled belt．The belt velocity have the“s”shape characteristic．A1l the results of the test show a very satisfied characteristic for belt drivingsystem．Advances in conveyor drive control technology in recent years have resultedin many more reliable．Cost-effective and performance-driven conveyor drive systemchoices for users．Among these choices，the Variable frequency control (VFC) methodshows promising use in the future for long distance belt conveyor drives due toits excellent performances．The NPC three-level inverter using high voltage IGBTs第8页 make the Variable frequency control in medium voltage applications become muchmore simple because the inverter itself can provide the medium voltage needed atthe motor terminals，thus eliminating the step-up transformer in most applicationsin the past．The testing results taken from the VFC control system with NPC three．1evel inverters used in a 2．7 km long belt conveyor drives in Chengzhuang Mine indicatesthat the performance of NPC three-level inverter using HV-IGBTs together with thecontrol strategy of rotor field-oriented vector control for induction motor driveis excellent for belt conveyor driving system．第9页在运送大量的物料时，带式输送机在长距离的运输中起到了非常重要的竞争作用。
机械毕业设计外文翻译
A Comparison of Drive Starting Mechanisms forAggregate Belt ConveyorsAbstractThe purpose of this paper is to describe the torque/speed characteristics，during starting conditions，of the most common drives used on belt conveyors today. Requirements of a Belt Conveyor DriveA belt conveyor is considered to be a constant torque device. In other words，the required driving torque is approximately constant at varying speeds (see figure l).other applications，such as a pump drive，have variable torque requirements(see figure2).However，to increase the speed of a conveyor additional torque must be added untilthe desired speed is obtained. Newton’s Second Law of Motion governs this relationship.∑F m a=The most straightforward example would be a constant acceleration torque(see figure3).In reality the acceleration torque is rarely constant. However，static calculation models as outlined in the Conveyor Equipment Manufacturers Association handbook (CEMA) make this assumption. When using static models the average acceleration torque is estimated over the entire acceleration time and assumed to be linear. Dynamic models，which are beyond the scope of this paper，allow acceleration torque values to vary in magnitude during the acceleration(or deceleration)Period.It should be noted that，given a constant load，a larger acceleration torque results in a faster acceleration time and also higher Peak belt tensions. Conversely，a smaller acceleration torque results in a longer start time and smaller Peak belt tensions. Across-The-Line AC Motor StartTechnically this is the simplest type of drive used on a belt conveyor. In this drive type an AC squirrel cage induction motor is started by simply throwing the contactor and energizing the motor. The resulting output torque，assuming that rated voltage is maintained，is strictly a function of the motor design. NEMA has Provided design standards that define the output torque characteristics of the most commonly used 3 Phase motors up to approximately 250 hp(figure4).In sizes larger than 250 hp manufacturers generally use the NEMA design codes in a relative manner(i.e.，NEMA C has a greater locked rotor torque than a NEMA B motor).The most critical locations on the AC motor speed/torque curve have been named for definition purposes. These common names are provided in figure 5.The most rigorous method of determining average acceleration torque，for static calculations，is to break the curve into several vertical sections，then sum the individual areas under the curve and finally divide by the number of sections.The more common way is to apply the following simplified equation:These static approximation methods work for most belt conveyors but can get the designer into trouble from time to time，especially on long and/or steep and/or fastconveyors. One item that needs to be examined is breakaway torque. Just because the drive provides enough average torque to accelerate the load doesn’t mean that it provides enough torque to break it away from zero speed and get it moving.CEMA defines breakaway torque as twice the torque required to overcome the total friction plus the torque required to lift the load vertically. Locked rotor torque (LRT) needs to be greater than breakaway torque! A good static Program makes this check.In addition to examining the effect that average torque has on the conveyor components the belt designer needs to determine the effect of peak torque. It is not uncommon for the breakdown torque (BDT) of a NEMA C motor to be greater than2.5 times full load torque (FLT).Generally the belting and Pulley manufacturers allowa transient overload of 1.5 times full load operating load. An across-the-line start can easily cause tensions to exceed these maximums. These higher than normal loads can be designed into the conveyor if they are known up front.Considering only average starting torque can cause the conveyor designer to undersize the take-up weight. It is not uncommon for conveyors with across-the-line starters to experience intermittent drive slip. This generally happens when Peak torque (BDT) is input by the drive and the take-up has been sized for average torque but not peak torque. The result can be devastating. When the drive pulley slips during this condition，the tension on the Tl and T2 sides (high and low)of the drive Pulley tries to equalize. This can subject a low tension bend or take-up pulley，just behind the drive pulley，to tensions that approach Tl tension. These Pulleys are rarely，if ever，designed for this load condition and the result is low tension Pulley failure. This condition is easily demonstrated with dynamic analysis.Another common Problem with across-the-line starts is caused by voltage dips during starting. If the power distribution system is not stiff enough to handle the huge inrush currents of an across-the-1ine start，the starting torque of the motors can be reduced to a Point that the conveyor will not start. This is due to the fact that the output torque ofan AC squirrel cage induction motor is reduced by the square of the applied voltage. In other words，a voltage drop of 10%would equate to a torque reduction of 19%. Reduced Voltage StartingThe reduced voltage starting of an AC squirrel cage induction motor is done for two basic reasons:1 .To reduce the inrush current that naturally occurs when a motor is Startedacross-the-1ine. A typical current/speed graph is shown in figure 6.It is not uncommon for the inrush current to be 6 times or more than it is at full load torque. As stated above high inrush currents cause the voltage in a power distribution system to sag. The cost of electrical power distribution equipment can become very high if it needs to be designed to handle the high inrush currents.2 . To reduce Peak motor torque during starting conditions，which subsequentlyincreases acceleration time. By reducing the Peak torques the conveyor components can be designed for lower tension loads. This primarily includes belting，Pulleys and external support structure. This can result in significant cost savings.Two common types of reduced voltage starters are the Current Limiting and the Constant Torque devices.Graphs are included above(figures 7 through 8) that depict the same motor/conveyor application with an Across-The-Line，a limitd Curren, and a constant Torque start. After studying the graphs it becomes apparent that the best use of the limited torque start is to protect the power distribution system from high inrush currents. The constant torque start reduces the high torque Peaks and Protects the conveyor’s mechanical components. In both cases the Start time is increased because the over all magnitude of accelerating torque is reduced. However，neither method will make it easier to start a“hard-to-start conveyor.”Correcting a hard starting conveyor is not areason to use a reduced voltage starter!翻译带式输送机驱动方式比较摘要本文的目的是描述最常见的机用输送皮带起动时的扭矩/转速特性。
机械专业毕业设计外文翻译10
翻译部分英文部分ADV ANCED MACHINING PROCESSESAs the hardware of an advanced technology becomes more complex, new and visionary approaches to the processing of materials into useful products come into common use. This has been the trend in machining processes in recent years.. Advanced methods of machine control as well as completely different methods of shaping materials have permitted the mechanical designer to proceed in directions that would have been totally impossible only a few years ago.Parallel development in other technologies such as electronics and computers have made available to the machine tool designer methods and processes that can permit a machine tool to far exceed the capabilities of the most experienced machinist.In this section we will look at CNC machining using chip-making cutting tools. CNC controllers are used to drive and control a great variety of machines and mechanisms, Some examples would be routers in wood working; lasers, plasma-arc, flame cutting, and waterjets for cutting of steel plate; and controlling of robots in manufacturing and assembly. This section is only an overview and cannot take the place of a programming manual for a specific machine tool. Because of the tremendous growth in numbers and capability of comp uters ,changes in machine controls are rapidly and constantly taking place. The exciting part of this evolution in machine controls is that programming becomeseasier with each new advanced in this technology.Advantages of Numerical ControlA manually operated machine tool may have the same physical characteristics as a CNC machine, such as size and horsepower. The principles of metal removal are the same. The big gain comes from the computer controlling the machining axes movements. CNC-controlled machine tools can be as simple as a 2-axis drilling machining center (Figure O-1). With a dual spindle machining center, the low RPM, high horsepower spindle gives high metal removal rates. The high RPM spindle allows the efficient use of high cutting speed tools such as diamonds and small diameter cutters (Figure O-2). The cutting tools that remove materials are standard tools such as milling cutters, drills, boring tools, or lathe tools depending on the type of machine used. Cutting speeds and feeds need to be correct as in any other machining operation. The greatest advantage in CNC machining comes from the unerring and rapid positioning movements possible. A CNC machine does dot stop at the end of a cut to plan its next move; it does not get fatigued; it is capable of uninterrupted machining error free, hour after hour. A machine tool is productive only while it is making chips.Since the chip-making process is controlled by the proper feeds and speeds, time savings can be achieved by faster rapid feed rates. Rapid feeds have increased from 60 to 200 to 400 and are now often approaching 1000 inches per minute (IPM). These high feed rates can pose a safety hazard to anyone within the working envelope of the machine tool.Complex contoured shapes were extremely difficult to product prior to CNC machining .CNC has made the machining of these shapes economically feasible. Design changes on a part are relatively easy to make by changing the program that directs the machine tool.A CNC machine produces parts with high dimensional accuracy and close tolerances without taking extra time or special precautions, CNC machines generally need less complex work-holding fixtures, which saves time by getting the parts machined sooner. Once a program is ready and production parts, each part will take exactly the same amount of time as the previous one. This repeatability allows for a very precise control of production costs. Another advantage of CNC machining is the elimination of large inventories; parts can be machined as needs .In conventional production often a great number of parts must be made at the same time to be cost effective. With CNC even one piece can be machined economically .In many instances, a CNC machine can perform in one setup the same operations that would require several conventional machines.With modern CNC machine tools a trained machinist can program and product even a single part economically .CNC machine tools are used in small and large machining facilities and range in size from tabletop models to huge machining centers. In a facility with many CNC tools, programming is usually done by CNC programmers away from the CNC tools. The machine control unit (MCU) on the machine is then used mostly for small program changes or corrections. Manufacturing with CNC tools usually requires three categories of persons. The first is the programmer, who is responsible for developing machine-ready code. The next person involved is the setup person, who loads the raw stork into the MCU, checks that the co rrect tools are loaded, and makes the first part. The third person is the machine and unloads the finished parts. In a small company, one person is expected to perform all three of these tasks.CNC controls are generally divided into two basic categories. One uses a ward address format with coded inputs such as G and M codes. The other users a conversational input; conversational input is also called user-friendly or prompted input. Later in this section examples of each of these programming formats in machining applications will be describes.CAM and CNCCAM systems have changed the job of the CNC programmer from one manually producing CNC code to one maximizing the output of CNC machines. Since CNC machine tools are made by a great number of manufacturers, many different CNC control units are in use. Control units from different manufacturers use a variety of program formats and codes. Many CNC code words are identical for different controllers, but a great number vary from one to another.To produce an identical part on CNC machine tools with different controllers such as one by FANCU, OKUMA or DYNAPATH, would require completely different CNC codes. Each manufacturer is constantly improving and updating its CNC controllers. These improvements often include additional code words plus changes in how the existing code works.A CAM systems allows the CNC programmer to concentrate on the creation of an efficient machining process, rather then relearning changed code formats. A CNC programmer looks atthe print of a part and then plans the sequence of machining operations necessary to make it (Figure O-3). This plan includes everything, from the selection of possible CNC machine tools, to which tooling to use, to how the part is held while machining takes place. The CNC programmer has to have a thorough understanding of all the capacities and limitations of the CNC machine tools that a program is to be made for. Machine specifications such as horsepower, maximum spindle speeds, workpiece weight and size limitations, and tool changer capacity are just some of the considerations that affect programming.Another area of major importance to the programmer is the knowledge of machining processes. An example would be the selection of the surface finish requirement specified in the part print. The sequence of machining processes is critical to obtain acceptable results. Cutting tool limitations have to be considered and this requires knowledge of cutting tool materials, tool types, and application recommendations.A good programmer will spend a considerable amount of time in researching the rapidly growing volume of new and improved tools and tool materials. Often the tool that was on the cutting edge of technology just two years ago is now obsolete. Information on new tools can come from catalogs or tool manufacturers' tooling engineers. Help in tool selection or optimum tool working conditions can also be obtained from tool manufacturer software. Examples would be Kennametal's "TOOLPRO", software designed to help select the best tool grade, speed, and feed rates for different work materials in turning application. Another very important feature of "TOOLPRO" is the display of the horsepower requirement for each machining selection. This allow the programmer to select a combination of cutting speed, feed rate, and depth of cut that equals the machine's maximum horsepower for roughing cuts. For a finishing cut, the smallest diameter of the part being machined is selected and then the cutting speed varied until the RPM is equal to the maximum RPM of the machine. This helps in maximizing machining efficiency. Knowing the horsepower requirement for a cut is critical if more than one tool is cutting at the same time.Software for a machining center application would be Ingersoll Tool Company's "Actual Chip Thickness", a program used to calculate the chip thickness in relation to feed-per-tooth for a milling cutter, especially during a shallow finishing cut. Ingersoll's "Rigidity Analysis" software ealculates tool deflection for end mills as a function of tool stiffness and tool force.To this point we looked at some general qualifications that a programmer should possess. Now we examine how a CAM system works. Point Control Company's SmartCam system uses the following approach. First, the programmer makes a mental model of the part to be machined. This includes the kind of machining to be performed-turning or milling. Then the part print is studied to develop a machining sequence, roughing and finishing cuts, drilling, tapping, and boring operations. What work-holding device is to be used, a vise or fixture or clamps? After these considerations, computer input can be started. First comes the creation of a JOBPLAN. This JOBPLAN consists of entries such as inch or metric units, machine type, part ID, type of workpiece material, setup notes, and a description of the required tools.This line of information describes the tool by number, type, and size and includes theappropriate cutting speed and feed rate. After all the selected tools are entered, the file is saved.The second programming step is the making of the part. This represents a graphic modeling of the projected machining operation. After selecting a tool from the prepared JOBPLAN, parameters for the cutting operation are entered. For a drill, once the coordinate location of the hole and the depth are given, a circle appears on that spot. If the location is incorrect, the UNDO command erases this entry and allows you to give new values for this operation. When an end mill is being used, cutting movements (toolpath) are usually defined as lines and arcs. As a line is programmed, the toolpath is graphically displayed and errors can be corrected instantly.At any time during programming, the command SHOWPATH will show the actual toolpath for each of the programmed tools. The tools will be displayed in the sequence in which they will be used during actual machining. If the sequence of a tool movement needs to be changed, a few keystrokes will to that.Sometimes in CAM the programming sequence is different from the actual machining order. An example would be the machining of a pocket in a part. With CAM, the finished pocket outline is programmed first, then this outline is used to define the ro ughing cuts to machine the pocket. The roughing cuts are computer generated from inputs such as depth and width of cut and how much material to leave for the finish cut. Different roughing patterns can be tried out to allow the programmer to select the most efllcient one for the actual machining cuts. Since each tool is represented by a different color, it is easy to observe the toolpath made by each one.A CAM system lets the programmer view the graphics model from varying angles, such as a top, front, side, or isometric view. A toolpath that looks correct from a top view, may show from a front view that the depth of the cutting tool is incorrect. Changes can easily be made and seen immediately.When the toolpath and the sequence of operations are satisfactory, machine ready code has to be made. This is as easy as specifying the CNC machine that is to be used to machine the part. The code generator for that specific CNC machin e during processing accesses four different files. The JOBPLAN file for the tool information and the GRAPHICE file for the toolpath and cutting sequence. It also uses the MACHINE DEFINE file which defines the CNC code words for that specific machine. This file also supplies data for maximum feed rates, RPM, toolchange times, and so on. The fourth file taking part in the code generating process is the TEMPLATE file. This file acts like a ruler that produces the CNC code with all of its parts in the right place and sequence. When the code generation is complete, a projected machining time is displayed. This time is calculated from values such as feed rates and distances traveled, noncutting movements at maximum feed rates between points, tool change times, and so on. The projected machining time can be revised by changing tooling to allow for higher metal removal rates or creating a more efficient toolpath. This display of total time required can also be used to estimate production costs. If more then one CNC machine tool is available to machine this part, making code and comparing the machining time may show that one machine is more efficient than the others.CAD/CAMAnother method of creating toolpath is with the use of a Computer-aided Drafting (CAD) file. Most machine drawings are created using computers with the description and part geometry stored in the computer database. SmartCAM, though its CAM CONNECTION, will read a CAD file and transfer its geometry represents the part profile, holes, and so on. The programmer still needs to prepare a JOBPLAN with all the necessary tools, but instead of programming a profile line by line, now only a tool has to be assigned to an existing profile. Again, using the SHOWPA TH function will display the toolpath for each tool and their sequence. Constant research and developments in CAD/CAM interaction will change how they work with each other. Some CAD and CAM programs, if loaded on the same computer, make it possible to switch between the two with a few keystrokes, designing and programming at the same time.The work area around the machine needs to be kept clean and clear of obstructions to prevent slipping or tripping. Machine surfaces should not be used as worktables. Use proper lifting methods to handle heavy workpieces, fixtures, or heavy cutting tools. Make measurements only when the spindle has come to a complete standstill. Chips should never be handled with bare hands.Before starting the machine make sure that the work-holding device and the workpiece are securely fastened. When changing cutting tools, protect the workpiece being machined from damage, and protect your hands from sharp cutting edges. Use only sharp cutting tools. Check that cutting tools are installed correctly and securely.Do not operate any machine controls unless you understand their function and what the y will do.The Early Development Of Numerically Controlled Machine ToolsThe highly sophisticated CNC machine tools of today, in the vast and diverse range found throughout the field of manufacturing processing, started from very humble beginnings in a number of the major industrialized countries. Some of the earliest research and development work in this field was completed in USA and a mention will be made of the UK's contribution to this numerical control development.A major problem occurred just after the Second World War, in that progress in all areas of military and commercial development had been so rapid that the levels of automation and accuracy required by the modern industrialized world could not be attained from the lab our intensive machines in use at that time. The question was how to overcome the disadvantages of conventional plant and current manning levels. It is generally ackonwledged that the earliest work into numerical control was the study commissioned in 1947 by the US governme nt. The study's conclusion was that the metal cutting industry throughout the entire country could not copy with the demands of the American Air Force, let alone the rest of industry! As a direct result of the survey, the US Air Force contracted the Persons Corporation to see if they could develop a flexible, dynamic, manufacturing system which would maximize productivity. TheMassachusetts Institute of Technology (MIT) was sub-contracted into this research and development by the Parsons Corporation, during the period 1949-1951,and jointly they developed the first control system which could be adapted to a wide range of machine tools. The Cincinnati Machine Tool Company converted one of their standard 28 inch "Hydro-Tel" milling machines or a three-axis automatic milling made use of a servo-mechanism for the drive system on the axes. This machine made use of a servomechanism for the drive system on the axes, which controlled the table positioning, cross-slide and spindle head. The machine cab be classified as the first truly three axis continuous path machine tool and it was able to generate a required shape, or curve, by simultaneous slide way motions, if necessary.At about the same times as these American advances in machine tool control were taking Place, Alfred Herbert Limited in the United Kingdom had their first Mutinous path control system which became available in 1956.Over the next few years in both the USA and Europe, further development work occurred. These early numerical control developments were principally for the aerospace industry, where it was necessary to cut complex geometric shapes such as airframe components and turbine blades. In parallel with this development of sophisticated control systems for aerospace requirements, a point-to-point controller was developed for more general machining applications. These less sophisticated point-to-point machines were considerably cheaper than their more complex continuous path cousins and were used when only positional accuracy was necessary. As an example of point-to-point motion on a machine tool for drilling operations, the typical movement might be fast traverse of the work piece under the drill's position-after drilling the hole, anther rapid move takes place to the next hole's position-after retraction of the drill. Of course, the rapid motion of the slideways could be achieved by each axis in a sequential and independent manner, or simultaneously. If a separate control was utilisec for each axis, the former method of table travel was less esse ntial to avoid any backlash in the system to obtain the required degree of positional accuracy and so it was necessary that the approach direction to the next point was always the same.The earliest examples of these cheaper point-to-point machines usually did not use recalculating ball screws; this meant that the motions would be sluggish, and sliderways would inevitably suffer from backlash, but more will be said about this topic later in the chapter.The early NC machines were, in the main, based upon a modified milling machine with this concept of control being utilized on turning, punching, grinding and a whole host of other machine tools later. Towards the end of the 1950s,hydrostatic slideways were often incorporated for machine tools of highly precision, which to sonic extent overcame the section problem associated with conventional slideway response, whiles averaging-out slideway inaccuracy brought about a much increased preasion in the machine tool and improved their control characteristics allows "concept of the machining center" was the product of this early work, as it allowed the machine to manufacture a range of components using a wide variety of machining processes at a single set-up, without transfer of workpieces to other variety machine tools. A machining center differed conceptually in its design from that of a milling machine, In that thecutting tools could be changed automatically by the transfer machanism, or selector, from the magazine to spindle, or vice versa.In this ductively and the automatic tool changing feature enabled the machining center to productively and efficiently machine a range of components, by replacing old tools for new, or reselecting the next cutter whilst the current machining process is in cycle.In the mid 1960s,a UK company, Molins, introduced their unique "System 24" which was meant represent the ability of a system to machine for 24 hours per day. It could be thought of as a "machining complex" which allowed a series of NC single purpose machine tools to be linked by a computerized conveyor system. This conveyor allowed the work pieces to be palletized and then directed to as machine tool as necessary. This was an early, but admirable, attempt at a form of Flexible manufacturing System concept, but was unfortunately doomed to failure. Its principal weakness was that only a small proportion of component varieties could be machine at any instant and that even fewer work pieces required the same operations to be performed on them. These factors meant that the utilization level was low, coupled to the fact that the machine tools were expensive and allowed frequent production bottlenecks of work-in-progress to arise, which further slowed down the whole operation.The early to mid-1970s was a time of revolutionary in the area of machine tool controller development, when the term computerized numerical control (CNC) became a reality. This new breed of controllers gave a company the ability to change work piece geometries, together with programs, easily with the minimum of development and lead time, allowing it to be economically viable to machine small batches, or even one-off successfully. The dream of allowing a computerized numerical controller the flexibility and ease of program editing in a production environment became a reality when two ralated factors occurred.These were:the development of integrated circuits, which reduces electronics circuit size, giving better maintenance and allowing more standardization of desing; that general purpose computers were reduced in size coupled to the fact that their cost of production had fallen considerably.The multipie benefits of cheaper electorics with greater reliability have result in the CNC fitted to the machine tools today, with the power and sophistication progtessing considerably in the last few years, allowing an almost artificial intelligence(AI) to the latest systems. Over the years, the machine tools builders have produced a large diversity in the range of applications of CNC and just some of those development will be reviewed in V olume Ⅲ。
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附录B专用车辆的特点随着汽车工业和市场的发展，社会对汽车运输的效率和经济性以及各种功能的要求也越来越高，从而使汽车运输工具向专业化发展成为必然规律。
从某种意义上说，汽车基本型仅能满足“量”的要求，完成一般的汽车运输，只有专业车辆才能更有效地发挥汽车运输的经济效益和专用功能，从而满足“质”的要求。
汽车运输专用车辆能保持运输货物的物理状态和质量，采用普通型运输，是有些货物在运输过程中可能会发生腐烂变质，在长途运输中，如肉类、蛋类若没有冷冻保鲜专业设备，尤其是在炎热的夏天肯定会变质。
如活鱼苗若没有防震、保湿、充氧气等专用功能，在长途运输中会死亡。
有些货物在运输过程中容易流式损坏，如水泥、玻璃、谷物、蔬菜等。
据我国经委运输研究报告，一些地区的水果、肉、鱼、鲜蛋不能及时外运，造成腐烂变质，年亏损达10亿元之多，而另一些地区却严重脱销。
汽车运输专用车辆能提高运输生产率，降低运输成本，减少劳动消耗、缩短装卸时间、实现最佳经济效益。
例如自卸汽车减少了装卸劳动力，液罐运输车自行装卸油液，洒水车具有自动加水、喷洒道路冲洗水沟的功能，混凝土搅拌车具有拌搅水泥石沙和将混凝土运输到建筑工地的功能。
普通型汽车是不可能完成这些功能的。
汽车运输专用车辆具有专门的防护设备对于一些易燃、易爆、易腐蚀、有毒等化学物质必须使用专用车辆来运输，普通型汽车是难以胜任这些物质的运输工作。
除公路运输外，对石油勘探、市政工程、环保卫生、消防、机场、医疗、建筑等野需要专用汽车运输。
由于专用车辆具有一些普通型汽车不能比拟的功能，近年来，世界各国都大力发展专用汽车，致力于专用车辆的研究，以扩大汽车的使用范围。
根据统计资料介绍，美国专用汽车的产量占汽车产量的58%，9t～11.8t 的中性汽车的保有量中，专用汽车占2/3以上。
日本专用车辆的保有量占中型货车的50%以上。
德国对专用车辆的需求量越来越大，不仅生产有工业、农业、林业、食品、市政等专用车辆，还生产有住宅式汽车、野外生活豪华型专用客车。
目前，专用车占整个货车保有量的70%以上。
综上所述，专用车辆是汽车运输发展的产物，与普通汽车相比具有能充分发挥汽车运输效率，降低运输成本、缩短装卸货物时间、减少劳动消耗和货物损失，特别是能保持货物的质量和使用价值，有利于各种类货物运输的优点。
我国专用车辆起步较晚，生产始于60年代初期，是在军用改装汽车哦基础上逐步发展起来的。
70年代一些生产专用车辆的厂家根据国民经济的不同需要形成了自己的产品特色，如汉阳特种汽车厂生产半挂车、武汉专用车辆厂生产粉罐式汽车、镇江冷藏汽车厂生产冷藏保温车、兰州专用汽车厂生产厢式汽车、青岛专用汽车厂生产自卸汽车等等。
80年代，专用车辆获得迅速发展，年生产能力达10多万辆。
特别国内各大汽车集团公司，如第一汽车集团公司、东风汽车公司、重汽车集团公司等都把专用车辆的开发放到了重要地位，为专用车辆的发展起到了重要作用。
从此，专用车辆已从形成行业阶段向逐步成熟阶段迈进。
目前，专用车辆已经成为国民经济中不可缺少的交通运输和工程作业的重要装备，专用车辆覆盖面越来越广泛。
近几年来一些专用车辆厂家在立足国内市场的基础上，已开始涉足国际市场，尤其是我国中位的专用车辆以其具有的可靠性，性能适中，价格低在第三世界国家中具有竞争能力。
综上所述，我国专用车辆有着广阔的发展前景。
据发展预测，到2000年国内需要的专用车辆产品基本能生产自给，而且逐步扩大专用车辆的出口量。
根据汽车发展的客观目标以及目前专用车辆的生产现状，在今后一个相当时期内，开发多品种、高技术、提高专用性能、扩大服务领域是专用车辆发展的总趋势。
近期内我国专用车辆发展重点主要归纳为以下几方面。
1.高等级公路专用车辆高等级公路的发展给汽车运输带来广阔的发展前景。
为了有效地发挥高等级公路的效益和功能，高等级公路专用车辆的发展主要考虑两个方面。
一方面是运输的专用车辆朝着大型化、专用化方向发展，如集装箱运输车、大型厢式汽车、大型罐式汽车、大型冷藏汽车、轿车运输车等。
另一方面是高等级公路服务用车辆。
为了保障高等级公路全天畅通无阻，必须配备相应的各种高等级公路管理专用车，如巡逻车、救护车、交通监理车、抢险车等。
为了对高等级公路进行养护和维修，要进行路面清扫、洒水、除草、除雪、修补路面、绿化以及交通工程设施的维护和抢修等都需要开发相应的专用车辆。
2．油田用专用车辆根据国家有关部门的要求，油田用运载工具的开发列入国家重大装备开发研制项目。
近期主要为满足新疆沙漠油田各种作业用的专用车辆，如油田固井车、压裂车、修井车、测井车等，将同步开发对目前已有的产品进一步改善提高。
3．机场专用车辆目前，机场各种用途的专用车辆主要依赖进口。
随着我国各主要大、中城市正在兴建现代化机场，急需与相配套的各种机场专用车辆，比如大型飞机加油车、飞机牵引车、电源车、跑道清扫车、升降平台车、货物运输车、旅客运输车。
The characteristics of professional vehiclesWith the auto industry and the development of the market and society on the auto transport efficiency and economy as well as various functional requirements are also getting higher and higher, so that the development of specialized car carriers to become essential law. In a certain sense, can only meet the basic vehicle of "quantity" requirements, the completion of the general motor transport, vehicles can only professional play a more effective vehicle for economic and transport functions, thereby satisfying the "quality" requirements.Motor transport vehicles for the transport of goods to maintain the physical condition and quality, general-use transport, some of the goods during transport corrupts may occur in the long-distance transportation, such as meat, eggs, if not frozen fresh professional equipment, especially in the hot summer will certainly degenerate. If not live fish such as earthquakes, moisture, oxygen filling, and other special features, will be in the long-distance transportation of death. Some of the goods during transport easy-flow damage, such as cement, glass, cereals, vegetables and so on. According to China's Economic Commission, Transport Study report, in some areas of fruits, meat, fish, eggs or timely Sinotrans, causing rotmetamorphism, the loss of as much as 1 billion yuan, and other areas are seriously out of stock.Motor Transport improve transport vehicles for productivity, and lower transport costs, reduce labor and reduces the turnaround time to achieve best value for money. For example, to reduce the Dump Truck handling labor, their own handling of a tank transporter of oil, with Automatic Sprinkler water, sprinkler irrigation ditch the function of roads, concrete mixers has stirred mixed sand and cement concrete transported to the construction sites will be the function of . Ordinary car it is impossible to accomplish these functions.Motor Transport specialized vehicles with specialized protective equipment for a number of flammable, explosive, corrosive, toxic chemical substances, such as vehicles to be used for transport, ordinary car it is difficult competence of the transport of these substances. In addition to road transport, oil exploration, municipal engineering, environmental health, fire, airport, medical, construction and other wild need special motor transport. As for vehicles with ordinary cars can not compare to function, in recent years, countries in the world have vigorously develop specialized vehicles, special vehicles to the research, to expand the use of the car. According to statistics, the United States dedicated automotivevehicle production accounted for 58%, 9 t ~ 11.8t neutral in the total number of motor vehicles, specialized vehicles account for more than 2 / 3. Japan accounted for vehicles MGV retained more than 50 per cent.Germany to the growing demand for the vehicles, not only are industrial production, agriculture, forestry, food, municipal, and other special vehicles, and domestic car production, and the wild life of luxury private bus. At present, the Special Purpose Vehicle for the entire tenure of the vehicle more than 70 percentTo sum up, and special motor transport vehicles are a product of the development, as compared with ordinary cars can give full play to motor transport efficiency and reduce the cost of transportation, loading and unloading of cargoes to shorten the time and reduce the loss of goods and labor consumption, particularly to maintain the quality of the goods and the value, to the carriage of goods of various types of benefits.My special vehicles late start, production began in the early 1960s, is in the military based on the modified car Oh gradually develop.1970s some of the production vehicle manufacturers for the different needs of the national economy in accordance with the formation of its own products, such as automobile productionplants Hanyang special semi-trailer, Wuhan special vehicles plant powder tank cars, automobile plant in Zhenjiang frozen refrigerated and insulated car, Lanzhou Special Purpose Vehicle production plants Van automobiles, automobile plant in Qingdao for the production dump truck, and so on. In the 1980s, there was a rapid development of specialized vehicles, the annual production capacity of over 10 million units. Special major domestic car company, such as the First Automobile Group, Dongfeng Motor Corporation, theFAW Group Corporation, and other heavy vehicles regard for the development has been put on an important position for the development of private vehicles has played an important role. Since then, the formation of special vehicles from the industry to phase gradually into the mature stage. At present, special vehicles have become indispensable to the national economy transport and works of important equipment, special vehicles more extensive coverage. In recent years a number of special vehicles manufacturers based on the domestic market on the basis of already begun to set foot in the international market, especially in China-dedicated vehicles with its reliability, performance, moderate, low price in the third world countries is competitive. To sum up, China's special vehicles have broad prospects for future development. According to forecast, in2000, the need for vehicles capable of producing basic subsistence products, and gradually expand the volume of exports for vehicles.According to automobile and the development of objective criteria for the current production status of vehicles in the future a considerable period of time, the development of more varieties, high-tech, special improve performance, and expand service areas for vehicles is the general trend of development. China's development of vehicles for the near future are summarized in the following key areas.1. Dedicated highway vehiclesHighway to the development of motor transport brought broad prospects for development. In order to effectively play the highway efficiency and performance, high-grade highways vehicles for the development of two major considerations. On the one hand, the transport of special vehicles in the large, dedicated the direction of development, such as vehicles, containers, large vans cars, large tank vehicles, large refrigerated vehicles, such as car transporters. On the other hand highway service vehicles. In order to protect the day uninterrupted highway, must be equipped with the corresponding variety of management for highway vehicles such as cars, ambulances, traffic Commissioner cars, and rescue vehicles. In order to carry out the conservation and highway maintenance, it isnecessary to carry out road cleaning, watering, weeding, snow, road repair, green and traffic engineering facilities maintenance and repair, and so needs to develop the corresponding specialized vehicles.2. Oilfield with special vehiclesAccording to the requirements of relevant departments, the development of the means of delivery of oil to major equipment included in the national development research project. To meet the recent major Xinjiang desert oilfield operations by the various special vehicles, such as cars oilfield cementing, fracturing cars, workover rig trucks, logging trucks, will be the simultaneous development of the current product has been further improved improve.3. vehicles for airportCurrently, the airport uses for the vehicles mainly rely on imports. As China's major big cities in the construction of modern airports, and the urgent need of accessories of all kinds of vehicles for the airport, such as large aircraft refueling vehicles, aircraft towing, power cars, trucks sweeping the runway, take-off and landing platform cars, goods vehicles, passenger vehicles, etc.11。