Working principle of clutch sub pump:

After the brake is applied, the main pump generates thrust, and the hydraulic oil pressure is inverted to the pump. The piston in the sub pump starts to move with the pressure of the liquid, and pushes the brake pad.

Detailed description: clutch master cylinder, sub pump, equivalent to two hydraulic cylinders. There is an inlet and outlet pipe on the main pump, and only one pipe is used in the sub pump. When the clutch is pressed, the pressure of the main pump is transmitted to the sub pump, the sub pump works, and the clutch fork is separated from the flywheel by the clutch fork, so that the shift can start. Release the clutch, the pump stops working, the clutch pressure plate and the disc contact with the flywheel, the power transmission continues, and the oil of the sub pump flows back into the oil pot.

The main function of the clutch sub pump is:

The top brake pad, the brake pad friction brake drum, make the vehicle speed down and static.