What is the primary function of the S-cam in brakes?

The primary function of the S-cam in air brake systems is to apply pressure to the brake shoes. This mechanism plays a crucial role in the operation of drum brakes. When air pressure is applied to the brake chambers, the S-cam rotates, pushing the brake shoes outward against the drum. As the shoes make contact with the drum, friction is created, which slows down or stops the vehicle.

Understanding the mechanics of the S-cam is essential for proper maintenance and troubleshooting of braking systems in commercial vehicles. This component ensures that braking is effective by converting the linear motion of the brake actuator into the radial motion needed to engage the brake shoes.