Drum brake is a traditional braking method, and its working principle can be vividly described with a coffee cup. The brake drum is like a coffee cup. When you put five fingers into the rotating coffee cup, your fingers are the brake pads. As long as you point your five fingers outwards and rub the inner wall of the coffee cup, the coffee cup will stop rotating.
To put it simply, the drum brake on a car is composed of a brake oil pump, a piston, a brake pad and a drum chamber. When braking, the piston is pushed by the high-pressure brake oil of the brake cylinder to exert force on the two half-moon-shaped brake shoes. , So that it is pressed against the inner wall of the drum, and the brake drum is prevented from rotating by friction to achieve the braking effect.