【正文】 ve variable speed and automation, in general, improve the production efficiency of roller paction and quality. Now foreign markets have seen very little mechanical transmission of the roller. Hydrostatic drive technology in the 1970s began to use bulldozers, and will soon be extended to a number of small and medium bulldozers and loaders, the United States John Deere, Caterpillar, Germany Bohai benefit panies and Dole produced by Komatsu of Japan has production and sales pushed Temple hydraulic machines and loaders. Hydrostatic drive not to use hydraulic torque converter, which dispense with the left lane and brake parts and mechanical drive, use of a safety valve on mechanical and hydraulic systems overload protection, and the index of smaller power play biggest index, its remaining power available in the auxiliary machinery operation. German pany Deutsche mark and Lee Bohai Fall of other public panies in 1954 and in 1955 took the lead in developing a hydraulic excavator , but the hydrostatic transmission in large excavator is the popularization and application of the 1970s. Since the early 1980s, excavators and subdivided, is gradually realized powered, rotary and the hydraulic excavator of. In the international market excavators, were all eliminated various mechanical drive. Late history of the birth of the road is more mechanical hydraulic drivebased, such as paver, soil stabilizer, Pavement milling machine, hydraulic transmission smoothness help improve the quality of the roads paved. Drilling in the car and drilling machines, hydraulic transmission has replaced the previous aerodynamic, Wheeled modern cranes and machinery also piling work to the whole in the direction of hydraulic development. Electricity in industrial production while the application has a long 邵陽學院畢業(yè)設計（論文） 5 history, but in mobile machinery is seldom used. This is because, firstly, to the motor capacity of, a motor with the same power as pared to the hydraulic motor, its weight and bulk to good times, to the machinery space layout brought great difficulties. In addition, the efficiency of electrical transmission over low efficiency and consumption of a large volume of nonferrous metals. But electric drive can be well realized variable speed, braking and electrical power streaming Drive more convenient and easy to large tub, large excavator and large loaders, enginegeneratorelectric wheels will transfer power. Germany Vogele also been developed for electric power will transfer wheel. Germany Vogele also been developed electric drive an asphalt paver, the aircraft39。s systems are all rotary motor driven electricity, Only Hopper CDCC and fort slab leveling tank still use hydraulic transmission. The other is the regional mobile operations in the smaller mining site, the use of electric drive large excavator loaders, Such use of electric drive power transmission cables without the engine installed on the machines. ergonomic innovations : a peopleoriented and simplified operation 1980s of the 20th century, Many of the world39。s operation and maintenance technologies, such drivers both improved working conditions, and increased production efficiency, and some of the engineering machinery vibration, noise, emissions and the prevention of roller drop from the development of the new standard, and even those laws. Now all kinds of projects are mechanical design roller defense and fallingobject protective devices to protect the personal safety of the drivers, with the cab and are designed and installed. Indoor driving sufficient human space and broad vision, and to take the necessary seals, vibration, noise and temperature control measures. Indoor chairs, pieces of the stick, gauges and the monitor according to ergonomics and design and minimize the 邵陽學院畢業(yè)設計（論文） 6 manipulation and control of parts. To reduce driver fatigue, to choose the suspension damping chairs, and to develop a gasliquid system hanging with the cab floor. Electronic technology, mechanical engineering applications, which greatly simplifies the driver39。s technical performance. The use of electronic control machine can automatically choose the mode of operation, such as excavators to the three operating modes boom priority, Rotary priorities and microadjustment tandem wheels all vibration and vibration. Electronic monitoring can detect and remove machines system failures, such as engine oil pressure loss. Fan fracture belt drive, hydraulic oil contamination or overheating and oil filter blockage, can promptly lights or audible alarm, by the use of electronic sensor