Composition and working principle of automatic transmission oil pressure regulating device

The oil pressure regulating device of automatic transmission oil supply system consists of main oil circuit pressure regulating valve, auxiliary pressure regulating valve, one-way valve and safety valve. The adjustment of main oil pressure of Volkswagen 0 1M and 0 1N automatic transmissions is mainly composed of main oil pressure regulating valve, main oil pressure booster valve, solenoid valve regulating valve and main oil pressure regulating solenoid valve N93. Among them, the main oil pressure regulating valve ensures the hydraulic stability of each system and makes the signal valve work smoothly by automatically regulating the oil pressure flowing to each hydraulic system. The main oil pressure regulating valve is composed of valve core, valve body, spring and other main components, which can automatically adjust the oil pressure according to the change of vehicle speed and throttle opening. Pressure oil from the oil pump enters from the oil inlet A and acts on the right end of the spool, and two feedback oil pressures from the reverse oil circuit of the throttle valve and the manual valve act on the left end of the spool through the oil inlet F. When the force generated by the oil pressure is greater than the pre-tightening force of the spring at the left end of the spool and the force acting on the spool by the throttle adjustment pressure, the spring will be compressed. When the spool moves to the left, the opening of the oil drain port increases, which reduces the oil pressure until the thrust generated by the oil pressure meets the pre-tightening force of the pressure regulating spring and the throttle regulating pressure. At this time, the oil pressure output by the pressure regulating valve is lower than the input pressure of the oil pump. The auxiliary pressure regulating valve also automatically adjusts the oil pressure, lubricating oil pressure and cooling oil pressure of the torque converter according to the change of vehicle speed and throttle opening. Its pressure regulating principle is the same as that of the main oil circuit pressure regulating valve. The safety valve, also known as the pressure limiting valve, consists of a spring and a steel ball, which are connected in parallel at the inlet and outlet of the oil pump to limit the pressure of the oil pump. When the pressure of the oil pump is high, the steel ball is pressed open and flows back to the oil pan through the oil return channel. Bypass valve is the protection device of hydraulic oil cooling device. When the temperature and pressure of the hydraulic oil flowing to the cooling device are too high, the valve body opens to bypass the cooling device, thereby preventing the high-temperature and high-pressure hydraulic oil from damaging the cooling device.