Working principle and structure of CCY14-1B motorized (servo) variable displacement pump

The pressure oil of the pump enters the lower chamber of the variable housing through the oil passage hole in the pump body and pump housing variable housing through the one-way valve. When the pull rod moves downward, it pushes the servo piston to move downward, and the upper valve port of the servo valve opens. The pressure oil (>5MPa) in the lower chamber of the variable housing enters the upper chamber of the variable housing through the oil passage hole in the variable piston. Due to the larger area of the upper chamber than the lower chamber, the hydraulic pressure pushes the piston to move downward, driving the pin shaft to rotate the variable head around the center of the steel ball, changing the tilt angle of the variable head (increasing), and the flow rate of the pump increases accordingly. On the contrary, when the pull rod moves upwards, the tilt angle of the variable head changes in the opposite direction, and the flow rate of the pump also changes accordingly. When the tilt angle reaches 0, the variable head changes towards the negative angle direction, causing the liquid flow to change direction and the inlet and outlet of the pump to change.