Brake caliper is a kind of clamp device with the functions of decelerating, stopping or maintaining the stop state of the moving wheel. It is generally only used in disc brake system.

The working principle of disc brake can be described by a plate. When the rotating plate is pinched by thumb and index finger, the plate will stop rotating. The thumb and index finger play the role of brake calipers.

The disc brake on a car consists of a brake oil pump, a brake disc connected to the wheel and a brake caliper on the disc. When braking, the high-pressure brake oil pushes the piston in the calipers and pushes the brake shoe to the brake disc to produce braking effect. Disc brake, which is divided into ordinary disc brake and ventilation disc brake. Ventilation disc brake is to reserve a gap between two brake discs to allow air to pass through the gap. Some ventilation discs drill many circular ventilation holes on the disc surface, or cut ventilation grooves or prefabricate rectangular ventilation holes on the disc surface. Ventilation disc brake uses air flow, and its cooling and heating effect is better than ordinary disc brake. The main advantage of disc brake is that it can brake quickly when braking at high speed. Its heat dissipation effect is better than drum brake. Its braking efficiency is stable and it is easy to install advanced electronic equipment like ABS.