Disc Brake System: Description and Operation

DISC BRAKE SYSTEM COMPONENTS
The disc brake assembly consists of a caliper assembly, rotor, and pads mounted to the steering knuckle.

OPERATION
Applying the brake pedal causes hydraulic pressure to move the caliper piston. The piston then forces the inboard brake pad against the inboard braking surface of the rotor. Increasing the force against the rotor causes the caliper assembly to move inboard. The outer brake pad then contacts the outboard braking surface of the rotor. The force of the two brake pads provides the desired clamping action on the rotor. Releasing the brake pedal relieves the pressure applied to the piston. The square cut seal in the piston bore returns to its normal position, allowing a small running clearance between the brake pads and rotor.