Provide a mounting base
The brake backing plate provides a stable mounting platform for other components of the braking system such as brake shoes. It is usually fixed to the axle or other chassis components to ensure that the brake shoes are mounted accurately in their intended position and that their position remains stable during the vehicle's journey.
Transmission of braking torque
When the driver depresses the brake pedal, the brake fluid pressure or mechanical force will push the brake shoes to move outward, making them contact with the brake drum (in drum brake system) or brake disc (in some special designs of disc brake system, it may also involve the backing plate to assist in transmitting the force) to produce friction, so as to achieve the braking of the vehicle. The brake backing plate serves to transmit the braking torque in this process. It transmits the braking torque generated by the friction between the brake shoes and the brake drum or disc to the vehicle's suspension system, axles and other components, ultimately slowing down or stopping the wheels.
Protecting internal components and preventing intrusion of foreign objects
The brake backing plate protects the brake components mounted inside. It can prevent foreign matter such as dust, water, mud and sand from entering the brake system, and prevent such foreign matter from damaging or affecting the normal operation of brake shoes, brake wheel cylinders and other components.
Assisting brake shoes to return to their original position
The brake backing plate works in conjunction with the brake shoe return springs and other devices to help the brake shoes return to their original position quickly after braking. When the driver releases the brake pedal, the return spring will pull the brake shoes back to the initial position, and the brake backing plate provides the mounting point and support structure for the return spring to ensure that the brake shoes can accurately and quickly return to the position, so that the braking system can be restored to the non-braking state, and to avoid abnormal abrasion and dragging phenomenon caused by the long-time contact between the brake shoes and the drum or disc.
