How does the vacuum booster work?
The brake booster pump uses the principle of inhaling air when the engine is working, causing one side of the booster to be vacuumed, and a pressure difference is generated with respect to the normal air pressure on the other side, and the pressure difference is used to strengthen the brake thrust. Even if there is only a small pressure difference on both sides of the diaphragm, due to the large area of the diaphragm, a large thrust can be generated to push the diaphragm to move toward the end of the pressure.
In the working state, the push rod return spring causes the brake pedal to be in the initial position. At this time, the check valve of the vacuum tube and the vacuum booster is in an open state, and inside the booster, the diaphragm divides it into vacuum gas. The chamber and the application chamber are connected to each other and are isolated from the outside for most of the time. The chamber is connected to the atmosphere by means of two valve means.
When the engine is running, the brake pedal is depressed, and under the action of the push rod, the vacuum valve is closed, and at the same time, the air valve at the other end of the push rod is opened, and after the air enters (the reason for pressing the brake pedal to generate a gasping sound) ), the state of the air pressure in the cavity will be unbalanced. Under the action of the negative pressure, the diaphragm is pulled toward the end of the brake master cylinder, which in turn drives the push rod of the master cylinder, which further enlarges the leg strength. The function.