Study Of The Proportional Control Technology Of Electricity And Fluid In The Work Installment Of Medium Bulldozer

The proportional control technology of Electricity and Fluid is rapidly develops in the nearly more than 30 years. It is the new branch of the proportional control technology of Electricity and Fluid that situated between the ordinary switch control technology and the servo-control technology. Its study is aims at some problem such as the big power loss, the strict request for liquor filters, the high cost of manufacture and the maintenance, useless of the rapidity in the general industrial equipment. It has some merits such as insensitive to the medium pollution, simple control principle, reliable work, high redundant precision, reasonable price, the product performance is more consistent. Therefore, it receives the people generally value. This technology also obtains the rapid development. Based on the character of proportional control technology of Electricity and Fluid, it is extremely appropriately to use it in the equipment automatic control of the bulldozer works.Along with science and technology development, people set the more and more request to the project machinery, such as operates facilely, safe and comfortable, and so on. But, at present, most fluctuation of bulldozer work installment is manual operated by the bulldozer driver in our country. The change of the bulldozer's outside shoulders are forecasted completely depends on person's feeling (vision and hearing) in the work process. So many flaws are existence inevitably. For example, slowness and not determinism, the low efficiency of Bulldozer work, worse work quality, operators'heavy labor intensity, shortens of bulldozer's service life.This study is for solve this difficult problem. The article analysis and study the present development tendency of bulldozer automatic control in domestic and overseas. In the article I designed a set of double channel control system, which works from the examination of the engine speed, the rate of Skid and the rotation to the control work equipment power elevation. It guaranteed the bulldozer can realize the work equipment automatic control under all the different coefficient of ground adhesion. The article elaborated detailed structure and design method of each constituent in the system, just as sensor, signal processing system, controller and execution. I designed the controller periphery electric circuit (sequence circuit, repositioned electric circuit, voltage power circuit) and the active filter periphery electric circuit. Considered the existence of disturbance, I designed the "dog that guards the door" electric circuit to resistance disturbance. I studied the hydraulic system of the bulldozer shovel. Based on original hydraulic system, I connected the proportional control system of electricity and fluid of the shovel and the loose earth teeth. Finally the system has realized that the bulldozer shovel and the loose earth teeth automatically adjust to reasonable position under the different operating situation. I has processed the simulation of the system by the software of Matlab/Simulink in Mathworks Corporation. I proposed the further program and measure of this design to improvement.