EXHAUST BRAKING

EXHAUST BRAKING

INTRODUCTION:

If the object is modern automobile, you simply apply the brakes. the brakes on the vehicle are designed to absorb tremendous energy of a moving vehicle or truck and covert the momentum into another form of energy i.e. heat. Brakes do this by using friction.

Various types of brakes for braking are as follows:

1) DRUM BRAKE:

A drum brake assembly consists of a cast iron drum, which is bolted to and rotates with vehicle wheel, and a fixed backing plates to which are attached shoes and other components, wheel cylinder, linkage, etc.
The shoes are surfaced with frictional lining, which contacts the inside of the drum when the brakes are applied. The shoes are forced outwards, against the action of the return springs by piston, which are actuated by hydraulic pressure.
As the drum rubs against the shoes, the energy of the moving drum is transferred into heat and this heat energy is passed into atmosphere.

2) DISC BRAKE:

Disc brake resembles the brakes on a bicycle the friction elements are in the form of pads, which are squeezed or clamped about the edge of a rotating wheel with disc brakes, this wheel is a rotor.
The rotor is made up of cast iron and the pads clamp against both sides of it. Usually they are separated to cooling.
The pads act perpendicular to the rotation of disc when the brakes are applied

3) POWER BRAKES:

Power brakes on passenger cars are used in conjunction with a basic hydraulic braking system.
All of them employ some sort of a booster unit, which acts like an extra strong foot on the brake pedal.
When the brake pedal depressed the booster unit multiplies the pedal force to the master cylinder.

4) ANTI-LOCK BRAKES:

During hard braking condition it is possible for wheels of a vehicle to lock resulting in reduced steering as well as braking.
An electronic sensor constantly monitors wheel rotation. If one or more of the wheels begins to lock the system open and closes solenoid valve, cycling up to 10 times per second. This applies and release brakes rapidly. Therefore with ABS vehicles never skid.

5) AIR BRAKES:

Air brakes and hydraulic brakes operate in similar fashion. The difference is that the air brakes are activated by compressed air instead of hydraulic pressure. Air brakes are used on heavy trucks.


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