Research On Locking Torque Converter And Latching Control Of Bulldozer

Torque converter is widely used in bulldozers and other construction vehicles,because it can increase vehicle starting torque, smooth start, shift non-impact and prevent overload stall, etc. However, the torque converter has shortcoming of low efficiency. Locking type torque converter was widely used in order to improve the transmission efficiency of the torque converter and reduce the fuel consumption of construction vehicles.Torque converter lock function has been studied extensively in the automotive sector. However, the technology is less research on construction vehicle, because of the complexity of the working condition of construction vehicles.It builds mathematical model of bulldozer transmission system,and analyzes matching of engine and hydraulic torque converter. Because of complex working conditions of the bulldozers and other construction vehicles, the paper designed the multi-plate locking type torque converter with a vibration reduction function for complex conditions. It is proved to suit for complicated operating conditions.According to the different working condition of the bulldozer, this paper designed the blocking rule for different working conditions which is based on the throttle opening and turbine speed, as well as a brake signal, transmission signals, gear and the cooling water temperature as auxiliary. The trigger signal model of blocking rule and closed to unlock point turbine speed classification model were established by use Simulink software, through simulation analyses verifies the rationality and correctness of this model.The bulldozer vehicle model was established by use MATLAB/Simulink software, and the vehicle model were simulation analyzed. The simulation results verify the accuracy of the latching control model. It provides a theoretical basis for look-up control research on bulldozers and other construction machinery.