The housing of the master cylinder is equipped with a front cylinder piston 7, a rear cylinder piston 12, a front cylinder spring 21, and a rear cylinder spring 18.
The front cylinder piston is sealed with a sealing ring 19; the rear cylinder piston is sealed with a sealing ring 16 and positioned with a retaining ring 13. The two reservoirs communicate with the front cavity B and the rear cavity A, and communicate with the front and rear brake wheel cylinders through their respective oil outlet valves 3. The front cylinder piston is pushed by the hydraulic force of the rear cylinder piston, and the rear cylinder piston is directly pushed by the push rod 15 push.
When the brake master cylinder is not in operation, the piston head and the cup in the front and rear chambers are located between the respective bypass holes 10 and the compensation holes 11. The spring force of the front cylinder piston return spring is greater than that of the rear cylinder piston return spring to ensure that both pistons are in the correct position when they are not working.
When braking, the driver steps on the brake pedal, the pedal force is transmitted to the push rod 15 through the transmission mechanism, and pushes the rear cylinder piston 12 to move forward. After the leather cup covers the bypass hole, the pressure in the rear chamber increases. Under the action of the hydraulic pressure of the rear chamber and the spring force of the rear cylinder, the piston 7 of the front cylinder moves forward, and the pressure of the front chamber increases accordingly. When you continue to step down the brake pedal, the hydraulic pressure in the front and rear chambers continues to increase, causing the front and rear brakes to brake.
When the brake is released, the driver releases the brake pedal. Under the action of the front and rear piston springs, the piston and the push rod in the master cylinder return to the initial position, and the oil in the pipeline pushes the return valve 22 back to flow Brake the master cylinder so that the braking effect disappears.
If the front cavity control circuit fails, the front cylinder piston does not generate hydraulic pressure, but under the hydraulic force of the rear cylinder piston, the front cylinder piston is pushed to the front end, and the hydraulic pressure generated by the rear chamber can still cause the rear wheel to produce If the control circuit of the rear cavity fails, the rear cavity does not generate hydraulic pressure, but the rear cylinder piston moves forward under the action of the push rod, and contacts the front cylinder piston to push the front cylinder piston forward, the front cavity can still produce The hydraulic pressure causes the front wheels to brake. It can be seen that when any set of pipelines in the dual-circuit hydraulic brake system fails, the master cylinder of the brake can still work, only the required pedal stroke increases.