Braking systems

• Brake type - principles
• Brake types
• Air brakes
• Exhaust brakes
• Electric brakes
• Parking brakes
• Engine brakes

Brake type - principles

Drum Brake

Drum brakes have a drum attached to the wheel hub, and braking occurs by means of brake shoes, expanding against the inside of the drum.

A drum brake is a brake in which the friction is caused by a set of shoes or pads that press against the inner surface of a rotating drum. The drum is connected to a rotating wheel.

Disc Brake

With disc brakes, a disc attached to the wheel hub maybe clamped between 2 brake pads.

On light vehicles, both of these systems are hydraulically operated. The brake pedal operates a master cylinder. Hydraulic lines and hoses connect the master cylinder to brake cylinders at the wheels.

Most modern light vehicles have either disc brakes on the front wheels and drum brakes on the rear, or, disc brakes on all 4 wheels.

Disc brakes require greater forces to operate them. A brake booster assists the driver by increasing the force applied to the master cylinder, when the brake is operated.

Antilock Braking System (ABS)

An anti-lock braking system (commonly known as ABS, from the German name "Antiblockiersystem" given to it by its inventors at Bosch) is a system on motor vehicles which prevents the wheels from locking while braking. The purpose of this is twofold:

Braking Systems : Braking fundamentals

• Drum & disc brakes
• Coefficient of friction
• Lever/mechanical advantage
• Hydraulic pressure & force
• Brake fade
• Regenerative braking
•  

Drum & disc brakes

Drum brakes have a drum attached to the wheel hub, and braking occurs by means of brake shoes, expanding against the inside of the drum.
With disc brakes, a disc attached to the wheel hub is clamped between 2 brake pads.
On light vehicles, both of these systems are hydraulically operated. The brake pedal operates a master cylinder. Hydraulic lines and hoses connect the master cylinder to brake cylinders at the wheels.
Most modern light vehicles have either disc brakes on the front wheels and drum brakes on the rear, or, disc brakes on all 4 wheels.
Disc brakes require greater forces to operate them. A brake booster assists the driver by increasing the force applied to the master cylinder, when the brake is operated.
The antilock braking system prevents wheel-lock or skidding, no matter how hard brakes are applied, or how slippery the road surface. Steering stays under control and stopping distances are generally reduced.
It consists of a brake pedal, a master cylinder, wheel speed sensors, the electronic control unit or ECU, and the hydraulic control unit, also called a hydraulic modulator.