Where are the brakes on a car

How do a car's brakes work?

The brakes are just as much a part of the safe operation of a car as the accelerator and clutch pedals. Without the controlled deceleration, a car would hardly be safe to drive. But what really happens inside the vehicle when you press the brake pedal?

The secret of the braking force is “hydraulics”. When the driver presses the brake pedal, the piston presses into a liquid. Since fluids cannot be compressed, the pressure is distributed throughout the braking system. Hydraulics is an easy way to generate great forces. A piston with a small diameter goes deep into a reservoir, this pushes another piston with a large diameter out again over a short distance. During this process, the force increases proportionally to the cross-sectional areas of the pistons used.



This is how linear motors and hydraulic presses are operated in industry. In addition to the increased pressure force, vehicles have a brake booster. This consists of a chamber in which a permanent vacuum is generated by the exhaust system or a separate pump. When you step on the brake pedal, the chamber is opened and the natural air pressure is used as an additional power source for the brake pressure. The brake booster approximately doubles the braking force.

What happens when you drive without a brake booster can be experienced when you let the car roll with the engine switched off. This makes the brake much more difficult to move. You can't damage anything with this driving style, but it is not recommended.



The opposing piston of the brake, which moves the brake lining, is now located on the wheel. Two constructions have prevailed: the disc brake and the drum brake. The brake disc of a disc brake is firmly screwed to the wheel and rotates with its speed.



The hydraulic ram, also known as the brake piston, is located in the brake caliper. This sits rigidly on the chassis and has two brake pads inside. The brake disc rotates between these two brake pads. When the brakes are applied, they move together and grind harder and harder on the brake disc. The vehicle's journey is slowed down further and further.