Freins

Freins, the French term for brakes, refer to systems used to slow or stop a vehicle by converting kinetic energy into heat through friction. In automotive and mechanical contexts, freins are the braking system that acts on the wheels to reduce speed or hold the vehicle stationary. The most common form is friction braking, typically implemented as disc brakes on two wheels and often drum brakes on the remaining wheels.

Disc brakes use calipers to squeeze brake pads against a rotating rotor (disc). Drum brakes use shoes pressed outward against a spinning drum. Most modern vehicles use hydraulic actuation, where brake fluid transmits force from the pedal via a master cylinder to the calipers or wheel cylinders. Electronic systems, such as anti-lock braking (ABS) and electronic stability control, modulate hydraulic pressure to prevent wheel lock and maintain steering control. Regenerative braking, used in many electric and hybrid vehicles, converts part of the vehicle’s kinetic energy back into stored electrical energy.

Key components include pads and shoes, rotors or drums, calipers or wheel cylinders, brake lines, brake fluid, and sensors or control modules for electronic systems. Maintenance involves checking pad and shoe wear, resurfacing or replacing rotors or drums, inspecting for leaks and contamination, flushing and replacing brake fluid at recommended intervals, and monitoring warning indicators. Common issues include excessive wear, leaks, reduced pedal feel, noise, and overheating or brake fade.

Historically, braking systems evolved from simple friction blocks to hydraulic and pneumatic systems, with ABS becoming common in the late 20th century and regenerative braking expanding with electrified powertrains.