The basis of a drum brake system. It is a circular metal component which rotates with the road wheel. A set of brake shoes which are fixed in position and act on the drum by expanding.
A metal housing, shaped like an oversized jar lid and bolted to an axle and a vehicle wheel. Brake shoes covered with a friction material are forced against the circular inner surface of the drum to stop the rotating wheel. Figure 2. Brake Drum
The shallow cylindrical rotating member of a drum brake. The friction material on the brake shoes (see) is pressed against its inside surface during braking.