Hydrostatic Transmission Wheel Loader Driving Axle Clutch Dynamic Proces Simulation And Experiment

Currently, as torque converter is adopted in the drive transmission part in domestic wheel loaders, the efficiency of driving transmission becomes lower. Meanwhile, the drive transmission part of wheel loaders abroad uses expensive infinitive variable gear-box; therefore, the cost is very high. In the thesis, based on the key research project of Changsong Heavy Machinery Factory, a new type of structure adopting driving axle clutch in place of infinitive variable gear-box is designed with regard to the problems of wheel loaders at present. The new structure, costing about the same, is much more efficient than domestic wheel loaders and has about the same efficiency as wheel loaders abroad with the cost reduced a lot.The gas controlled driving axle clutch is the core part of hydrostatic transmission wheel loaders. The load has a mass weight and is heavy-loaded while working, so when the clutch gradnally couple at start,the misloading of pressure tends to result in the problems of acute impact and more grade abrasion, which greatly lowers the runing smoothness of the mouhine and shortens the longevity of the transmission parts. By emulation and platform experiment, the qualities of the clutch coupling under different pressures are compared, and the suitable pressure value is achieved, which can be used as the reference for controlling actual machines. It is the main researching aim of this thesis.In the thesis, first, the framework of driving axle clutch on hydrostatic transmission wheel loaders is designed and at the same time, drawings of its structure and mechanism are made. According to the technical requirements of the drive transmission part on the hydrostatic transmission wheel loaders to the driving axle clutch, air pressure controlled planet gear is designed on the rim of wheels to constitute the low speed working gear, direct gear turntable then becomes the driving axle clutch at the high speed working gear. In the thesis, a detailed analysis of the combining process of the driving axle clutch on the hydrostatic transmission wheel loaders is given and also a dynamics model concerning its working process is made. Furthermore, detailed mechanic analysis has been conducted and the frictional moment, resistance moment and the moment of inertia are all confirmed, thus the model of the input gas pressure controlling the working of the driving axle clutch established.Studies on the combining quality of the gas controlled driving axle clutch have been carried out to establish a mathematic model based on the parameters of friction and concussion produced by the combining quality experiment. According to the established dynamic model, the SIMULINK model concerning the process of driving axle clutch's dynamic combining process is made with the help of simulation software MATLAB. Simulation on charging air pressure, angel speed, angel acceleration, friction and concussion are made based on three different types of situation. During the process, the area of input air hole and the impact produced by the moment of inertia on the simulation result are both taken into consideration. According to the simulation results, the best value of input gas pressure required is 980K PA while the driving axle clutch is combining.In the thesis, experimental research is conducted on the driving axle clutch of hydrostatic transmission wheel loaders. Other two experiments are also carried out: platform experiment by increasing load with the help of chassis work measuring tool and the experiment on controlled gas pressure value, cylinder piston and the solar wheel rotating angle speed during the combination of driving axle clutch. This paper has supervising significance on controlling actual machines, and also provides practical engineering value for the development of new type of driving axle clutch.