Research on a New Type of Buffering Valve for Vehicle Shifting

The traditional buffering valve for vehicle shifting mainly relies on the throttle hole and spring to control the pressure in the clutch. However, its accommodative facility and adaption are inferior. Therefore, two–dimensional (2D) digital technology is proposed to be applied to the vehicle shift buffering area, and the 2D digital buffering valve is designed. This study introduces the structure and working principle of the 2D digital buffering valve and establishes the mathematical model of the 2D digital buffering valve. The classical proportional–integral–differential control algorithm is adopted and Matlab/Simulink is used to simulate its control model. Finally, an experimental study is carried out. The study results show that when the frequency is 50 Hz, the amplitude of the valve output pressure decays to −3 dB, and when the frequency is 60 Hz, the phase of the valve output pressure lags by 90°. The output of the 2D digital buffering valve meets the requirement of the change of the oil pressure in the clutch during the vehicle shifting process. The control precision of its buffering pressure characteristic reaches 15%. The simulation and test results of the buffering valve are consistent, which verifies the correctness of the simulation model.