There are different types of air brakes used in buses and trucks, with one type being used most commonly. Foundation brakes employ a triple-valve principle, which means when air builds in the lines, it the brakes ease up. Most trucks and buses that use air brakes have what is referred to as the graduated release system. This means that when the pressure on the brakes is eased, the brakes release is proportionate. This allows for just the right amount of braking for larger vehicles when they are on downgrades.
The foundation system is made up of a number of Air Brake Parts. The air compressor sends air to the storage tanks, where it is held until it is needed for braking. The governor of the compressor controls how much air goes in and out of the air compressor so there is always a specific amount of air in the tanks. The air reservoir holds compressed air that the system uses, and drain valves are located in the air tanks to get rid of air when the automobile is not being used. Other parts include:
* Brake Pedal – When pressure is applied to the petal, air comes from the air reservoir tanks.
* Brake Chambers – These are cylindrical in shape. They hold a slack adjuster. This moves a mechanism known as a cam or a diaphragm.
* Push Rod – This connects the slack adjuster to the brake chambers. When it is pushed in, the brakes are not in use. When it is out, the brakes are being used.
* Brake S-Cam – This holds the shoes apart and ensures that they are pressed to the brake drum.
* Brake Shoes – These are made from steel, and creates friction when they rub on the brake drum.
* Return Spring – This is attached to both sides of the shoes. It ensures that they go back to the open position.
These and other Air Brake Parts, as well as many automotive parts, are available from Truck Parts and Equipment Inc. Visit the website www.tpetruckparts.com to find out more about heavy duty automotive parts. There are also mechanics on duty for transport truck repair.