Saturday, 12 September 2015

Air Brake System : Principle and Working

Today we will learn about air brake system. We know that form time to time we increase the load carrying capacity of vehicle. For the heavy load we need a high power braking system. Air braking system is one of them. Air brakes are commonly used on heavy vehicles, like trucks, buses, etc.

As we discuss according to construction there is only two types of braking system disk brake and drum brake. But due to heavy load where it is not possible for human to generate the braking force some other system are used to generate braking force which force the braking pads to disk or drum which further generate friction force and stop the vehicle.

In the air brake system we use air to generate this force. This type of braking is similar to the hydraulic brakes expect that in their case compressed air is used to apply brakes instead of hydraulic pressure.

Air Brake System:

Principle of Air brake system:

Air brake is better understood by the layout of as shown in figure. The compressor takes air form the atmosphere through the filter and the compressed air is sent to the reservoir through the unloader valve, which gets lifted at a predetermined reservoir pressure and relieves the compressor of load. Form the reservoir the air goes to various accessories and also to the brake chambers also called the diaphragm units at each wheel, through the brake valve. 
Air Braking System

The control of brake valve is with the driver who can control the intensity of braking according to the requirement. When the brakes are applied, the pressure in the reservoir decreases. When the pressure drops to approximately 700kPa, the governor again cuts in the compressor to raise system pressure. In case the air system pressure falls to about 400 kPa, a warning usually in the form of a buzzer is sounded.

Advantage of air brake:

1. Air brake system are much more powerful than the ordinary mechanical or hydraulic brakes and that is the reason they are exclusively used in heavy vehicles.

2. They are easy to install on chassis because it is interconnected by pipes.
The compressor airs can also use for tyre inflation, windscreen wipers, horns and many other accessories. 

Today we have discussed about air brake system. If you have any query, ask by commenting. 

1 comment:

  1. Explain the function of governor in air brake system