1.Structure of drum brakes
A drum brake is a braking system with a drum (rotor) that rotates with the wheel. Inside each drum are brake shoes with brake linings (friction material). The piston (pressure mechanism) presses on the drum from the inside to generate the braking force, which makes it possible to decelerate and stop the vehicle.
2.How drum brakes work
When the driver depresses the brake pedal, the power is amplified by the brake booster (servo system) and converted into hydraulic pressure (oil pressure) by the master cylinder. The pressure reaches the brakes on the wheels through pipes filled with brake fluid (brake fluid). The transmitted pressure pushes the pistons on the four wheel brakes. The piston presses the brake lining, which is the friction material, against the inner surface of the brake drum, which rotates with the wheel. The liner is pressed against the drum, which in turn slows the wheels, thereby slowing and stopping the vehicle.
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