附 录附录A 英文科技文献Disassembly Automotive OverviewCar shortly after the invention of the automobile repair and then had the industry. In order to convenient maintenance， with jack lifting machine maintenance tools to appear. The early simple columnar foundation type hydraulic lifting machine， is greatly raised than it was still early jack and the function of the test bench， this early lifting machine can rotate function in lifting the car later， rotating 360 . Maybe you often go to a car maintenance， now still use the lift machine to provide daily vehicle maintenance service， this kind of lifting machine has largely work for 75 years. Along with the development of the car industry， simple columnar type elevator machine design， the limitation of shows up soon. If only in car around for testing maintenance work of words， the lifting machine will be enough， but this lifting machine and the central pillar of the hoist boom would hamper into the bottom of the car most area. For simple columnar type elevator machine of these limitations， engineers have put forward a lot of lifting machine design scheme and a lot of improvement work. Now， lifting machine selection scope of great， have foundation type， spots， cut the type， type of parallel four edges form， portable， simple columnar type， double column type， four-column type， driving type， contact the car battery， symmetric， the symmetric， small trip， big lift， queue， and other various type of lifting machine design. Some lifting machine may also. In the market can see different types of different size， lifting machine， there are some particularly suitable for engaged in special type of maintenance work， there are a few lifting machine for some other maintenance work. Double column spots car battery lifting machine is contact a widespread adoption of lifting machine， in recent years all new sales lifting machine， at least two-thirds are this type. This design is very popular， there are several reasons: one is the lifting machine installation quick， do not need a wide range of excavation， also do not need to enterprises whole layout some permanent changes. 2 it is the diversity of function， a double column spots car battery lifting machine with almost all can be used for the car maintenance work. The lifting of the machine and contact the layout of cantilever pad， making maintenance technician can easily into the bottom of the car， the car in operation and maintenance. Therefore， almost all major lifting machine manufacturers to at least one type of production double column spots type elevator machine. In recent years， I had a booming industry， especially the car industry， DuoNian to cars into the ordinary families dream has become a reality. Vehicle repair industry has got to develop， all kinds of maintenance equipment needs rapid expansion. Auto lift machine is necessary maintenance， is also the most important maintenance machinery. Auto lift machine is the role of the need of repair car level to the appropriate height， so that maintenance workers in car chassis of automobile maintenance. Below Auto lift machine such as mentioned above， the main divided into pillar type and shear type two kinds， no matter which kind of， the demand from both sides to car level synchronization up， and cant happen migration. And car chassis below must be empty. To facilitate the maintenance workers homework. This requires auto lift machine lifting device must be on both sides of the separation of both sides， and rise or fall must be synchronous. Because of the weight of the car generally very big， and lift for special smoothly， so auto lift machine typically use the hydraulic drive system. Besides the requirement from a certain range from cars both sides synchronous lifting the decline and car， also requires its can make cars at any height to stop and to keep still， so that different height of the workers in maintenance， at different location can adjust height， the most convenient for repair， so hydraulic system must have positioning keep function. In addition for car weight is very big， once hydraulic system failure， lifting machine for arm in car the force of gravity will decline rapidly to pull off the maintenance workers may be the life security threats， lifting the car on and broke the danger. So in order to prevent this happens， lifting machine must have mechanical locking devices， mechanical locks were installed in by lifting cylinder piston rod and the top and lifting arm connected pin shaft on the two root jagged rack， installation of the oil cylinder to the outside of the rack is stationary. And can the pin shaft do certain Angle， to the swing of the separation of the two root rack and mesh. When lifting arm in positioning state or hydraulic system failure， hydraulic below a certain value， dynamic rack will of its own gravity and spring under the action of forces and still rack meshing， mechanical locked， increased the lifting the security of the machine.