Pressing down on the brake pedal pulls against cables attached to the brake shoe expanding device. The brake shoe expanding device consists of a lever or cam that is actuated or rotated to push one end of the brake shoe out. The other end of the brake shoe is attached to the brake backing plate by air anchor pin.
Mechanically operated parking brakes on most cars make use of a foot or hand brake connected by cables to the rear wheel brake shoes or to a separate brake drum that is a part of the transmission shaft. The hand lever, when pulled, pulls cable that operates levers in the two rear wheel brake mechanisms. The levers as they operate, force the brake shoes apart and in to contact with the brake drum.