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BRAKE SYS

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MEDBRAKE SYS

The brakes of a veh have to absorb all the energy given to

the veh by the engine and due to the momentum of the veh

This energy must then be wasted or dissipated

In most veh brakes, the energy is absorbed by friction,

converted into heat and the heat dissipated by the stream

of air passing under and around the veh

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MEDBRAKE SYS

The front brakes play a greater part in stopping the car than

the rear ones, because braking throws the car weight

forward on to the front wheels.

Many cars therefore have disc brakes, which are generally

more efficient, at the front and drum brakes at the rear

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HYD BRAKE SYS

MEDHYD BRAKES

Hyd brakes are applied by the driver through an actuating

sys using hyd principles to multiply the brake pedal force

In a brake actuating sys, the enclosed vessel is a master cyl

and a wh cyl with connecting lines and hoses

Any pressure applied to the master cyl is transmitted

undiminished to each wh cyl

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MEDHYD BRAKES

As the brake pedal is depressed, the rod pushes the piston

of the master cyl, thus applying pressure to the brake fluid

Moving through pipes and hoses to the whl cyl, the fluid

forces apart the cyl pistons, and the later press the shoes

against the brake drums

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MEDHYD BRAKES SYS

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DISK BRAKES

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MEDDISK BRAKES

A disc brake has a disc that turns with the wh

The disc is connected by a caliper, in which there are small

hyd pistons worked by pressure from the master cyl

The pistons press on friction pads that clamp against the

disc from each side to slow or stop it

The pads are shaped to cover a broad sector of the disc

There may be more than a single pair of pistons, esp in dual-

circuit brakes

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MEDDISK BRAKES

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DRUM BRAKES

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MEDDRUM BRAKES

A drum brake has a hollow drum that turns with the wh

Its open back is covered by a stationary back plate on which

there are two curved shoes carrying friction linings

The shoes are forced outwards by hyd pressure moving

pistons in the brake's wh cyl

The linings is pressed against the inside of the drum to slow

or stop it

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MEDDRUM BRAKES

Each brake shoe has a pivot at one end and a piston at the

other

A leading shoe has the piston at the leading edge relative to

the dir in which the drum turns

It is simpler but less powerful than the two-leading-shoe

system, and is usually restd to rear brakes

Shoe travel is kept as short as possible by an adjuster

Brakes have automatic adjustment by means of a ratchet

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MEDDRUM BRAKES

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THANK YOU

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