| This text combines the fund project of national natural science (59705005) "Study on Engineering Vehicle Electronic Control for Saving Energy" and the key teacher fund project of Ministry of Education "Study on Improving the Performance of Drive and Economy of AT System of Engineering Vehicle",in order to solve the problem of Engineering vehicle hydrodynamic drive system degrade largely under heavy load and regard improving the motive force of the vehicle as object,the theory and experiment of three parameters was researched around Automatic Transmission Technology. Include the following content mainly:First. Introduction of Automatic Transmission TechnologyState the meaning of studying the Automatic Transmission Technology of vehicle,according to its stage of development,introduction the development course and characteristic about the earlier stage of automatic transmission,the stage of hydraulic automatic transmission,the stage of automatically controlled automatic transmission and the stage of intellectual automatic transmission and the current situation of the development and development trend at home and foreign,and point out that the intelligent control system,the vehicle electron integrates are two major characteristics that are a technological development trend of automatic transmission. The necessity of the automatic transmission was explained and scientific research situation and the situation of application at present were introduced in the engineering vehicle,and has listed the research contents of this text.Two. The transmission characteristic of the engineering vehicleRegard wheeled loader as the instance,the working characteristic of them,include the engine,the hydraulic torque converter,the gearbox,the transaxle,the wheel,were analyzed. The characteristic of engine and hydraulic torque converter mainly were researched,and point out the engine under full-load,its output power,oil position and rotational speed have the relation and the engine operating mode influence the power and economy of the transmission,and hydraulic torque converter working in high-efficient district can raise power and economy of transmission,the conclusion that the working state of them is the main reason that influence the economy and motive force of vehicle was gained . In addition,to reduce the number of change of gear can contribute to saving energy of the transmission. Three. Research of the automatic transmission shift scheduleThe shift schedule is key technology of the automatic transmission,summarize single parameter schedule,two parameter schedule,three parameter schedule and intelligent schedule that automobile exist at present,analyze the best power and best fuel economy shift characteristic. Have compared two kinds of two parameter shift schedule of engineering vehicle,the tactics of the shelf of rotational speed of pump and rotational speed of turbine has a actual meaning even more. Considering the power of vehicle through regarding the engine and hydraulic as a whole,analyzing their common performance characteristics,a shift schedule of three parameter has proposed with position of the throttle,the rotational speed of pump and the rotational speed of turbine,and has received shift forms and made the automatically controlled scheme. In addition,intellectual control relatively has developing on a large scale and prospects on the engineering vehicle.Four. Computer simulation of the control system Explained purpose and meaning of applying the simulation of the computer to the automatic transmission. Have set up mathematics models of the engine,hydraulic torque converter,gearbox,transaxle and wheel,and vehicle load models. Regard a rotational speed of pump and rotational speed of turbine as the variable,the dynamics equation of the vehicle transmission has set up. The controlled models have established according to three parameter shift schedule,finally supported by Matlab/Simulink figure modeling technology,the vehicle transmission dynamics emulation s...
|
PDF Full Text Request