Brakes work by converting the kinetic energy of a moving vehicle into thermal energy through friction. When the brakes are applied, brake pads or shoes press against the spinning brake drums or discs on the wheels. This squeezes the drums/discs and causes friction, slowing the vehicle's motion as the kinetic energy is dissipated as heat. Modern brakes mostly use hydraulic systems to transfer pressure from the brake pedal to the calipers at each wheel via brake lines, causing the pads/shoes to clamp onto the drums/discs when braking. Disc brakes mount the friction material to a caliper that squeezes a disc attached to the rotating wheel hub, while drum brakes use shoes that are forced against
2. WORKING OF BRAKES
•A COMMON MISCONCEPTION ABOUT BRAKES IS THAT BRAKES SQUEEZE
AGAINST A DRUM OR DISC, AND THE PRESSURE OF THE SQUEEZING
ACTION SLOWS THE VEHICLE DOWN. THIS IS IN FACT A PART OF THE
REASON FOR SLOWING DOWN A VEHICLE.
•ACTUALLY BRAKES USE FRICTION OF BRAKE SHOES AND DRUMS TO
CONVERT KINETIC ENERGY DEVELOPED BY THE VEHICLE INTO HEAT
ENERGY.
•WHEN WE APPLY BRAKES, THE PADS OR SHOES THAT PRESS AGAINST THE
BRAKE DRUMS OR ROTOR CONVERT KINETIC ENERGY INTO THERMAL
ENERGY VIA FRICTION.
THUS BRAKES ARE ESSENTIALLY A
MECHANISM TO CHANGE ENERGY
TYPES
5. DISC BRAKES
1. In a disc brake, the fluid from the
master cylinder is forced into a
caliper where it presses against a
piston.
2. The piston in turn squeezes
two brake pads against the disc
(rotor), which is attached to
wheel, forcing it to slow down or
stop.
7. DISC BRAKE AND BRAKE OF A
BICYCLE
1. Similar to a bicycle brake where two rubber pads run
against the wheel rim creating friction.
2. But in a disc brake, the brake pads
squeeze the rotor instead of the wheel,
and the force is transmitted hydraulically
instead of through a cable.
8. Component in brake system :-
1. Master cylinder
2. Brake buster
3. Proportioning valve
4. Brake line
5. Wheel cylinder
6. Brake pade
7. Caliper
10. MASTER CYLINDER IN ACTION
1. Pressure is built in the cylinder and
the lines as the brake pedal is depressed
further.
2.The pressure between the primary and
secondary piston forces the secondary
piston to compress the fluid in its
circuit.
3. If the brakes are operating properly,
the pressure wll be same in both the
circuits.
4. If there is a leak in one of the circuits,
that circuit will not be able to maintain
pressure.
11. Proportioning Valves
1. Reduce the pressure to the
rear brakes
2. Diagonal systems require two
3. Split and slope are changed to create
proper balance
12. DISC BRAKE AND BRAKE OF A
BICYCLE
1. Similar to a bicycle brake where two rubber pads
run against the wheel rim creating friction.
2. But in a disc brake, the brake pads squeeze the
rotor instead of the wheel, and the force is
transmitted hydraulically instead of through a
cable.
14. SOME MORE POINTS
1. Most modern cars have disc brakes on front wheels
and drum brakes on rear wheels and some wheels
have disc brakes on all four wheels.
2. To increase safety, most modern car brake systems
are broken into two circuits, with two wheels on each
circuit.
3. If a fluid leak occurs in one circuit, only two of the
wheels will loose their brakes and the car will still be
able to stop when we press the break pedal.
15. BRAKE FLUIDS
1. One of the important characteristics of
brake fluid is its BOILING POINT.
Hydraulic systems rely on incompressible
fluid to transmit force.
2. Liquids are generally incompressible while
gases are compressible.
3. If the break fluid boils (becomes a gas), it
will loose most of its ability to transmit
force.
4. This may partially or completely disable
he brakes.
16. TYPES OF BRAKE FLUIDS
FLUIDS
GLYCOL BASED
(ABSORB
WATER)
DOT 3
DOT 4
SILICON BASED
(DOESN’T
ABSORB WATER)
DOT 5
17. PRECAUTIONS
1. As a DOT 3 or DOT 4 brake fluid absorbs
water, its boiling point decreases. It can absorb
water from air, that is why we should avoid
opening the car’s brake fluid reservoir and the
container of the brake fluid should be tightly
sealed.
2. Also DOT 3 and DOT 4 brake fluids eat paint.
3. None of the different types of brake fluids
should be mixed. They can react badly with each
other and corrode the brake system.