In an automotive braking system, the brake pads, brake discs, and calipers are the core actuating components. The three have distinct roles and work together to decelerate and stop the vehicle. Understanding the function of each component helps clarify the braking logic and facilitates daily inspection and maintenance.

1. Brake Caliper: The actuator of braking force

The brake caliper acts as the "executive arm" of the braking system. Its main roles are to house the pistons, transmit hydraulic pressure, and push the brake pads against the disc.

When brake fluid pressure enters the caliper, the pistons are pushed outward, and the caliper forces the brake pads to contact the disc. The caliper not only provides clamping force but also determines the magnitude and uniformity of braking force. Multi‑piston calipers and fixed calipers increase clamping stability and are key components affecting braking performance.

2. Brake Pad: The friction core of braking

The brake pad is the component that directly generates friction, acting as the "friction layer" of the braking system.

Pushed by the caliper, the pad presses against the high‑speed rotating disc, converting the vehicle's kinetic energy into heat through friction to achieve deceleration. The pad material directly affects pedal feel, noise, wear rate, and high‑temperature resistance. Brake pads are consumables and require regular thickness checks and timely replacement.

3. Brake Disc: The foundation of braking force

The brake disc is the metal disc that rotates with the wheel, serving as the "force‑bearing carrier" of braking.

It provides a stable friction surface for the pads, withstands clamping force and high temperatures, and quickly dissipates the heat generated by friction to prevent brake fade. The disc's material, size, and groove design (curved, drilled, plain, or fishbone) all affect heat dissipation efficiency, braking stability, and service life.