drum brake

machine component

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Last updated

June 25, 2026

Quick Summary

A drum brake is a type of brake that functions by using friction from shoes pressing against the inside of a rotating drum. This mechanism is used to slow down or stop a moving object by converting kinetic energy into heat through friction.12

In automobiles, drum brakes were an earlier technology, often mechanically actuated. However, they were eventually replaced by hydraulic systems for more consistent braking force. While disc brakes are now more common due to their superior heat dissipation and fade resistance, drum brakes are still used, particularly on the rear wheels of some vehicles.3

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automobile
Brakes
…stopping vehicles were mechanically actuated drum brakes with internally expanding shoes; i.e., foot pressure exerted on the brake pedal was carried directly to semicircular brake shoes by a system of flexible cables. Mechanical brakes, however, were difficult to keep adjusted so that equal braking force was applied at each wheel;…
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…stopping vehicles were mechanically actuated drum brakes with internally expanding shoes; i.e., foot pressure exerted on the brake pedal was carried directly to semicircular brake shoes by a system of flexible cables. Mechanical brakes, however, were difficult to keep adjusted so that equal braking force was applied at each wheel;…
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bicycle
Brakes
Drum brakes that force two arcs of friction material against the inside of a steel drum on the hub are less common. Disc brakes have been designed for mountain bikes. They squeeze against a metal disc located near the hub instead of against the rims.
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Drum brakes that force two arcs of friction material against the inside of a steel drum on the hub are less common. Disc brakes have been designed for mountain bikes. They squeeze against a metal disc located near the hub instead of against the rims.
Read More