US Patent 7510057 Parking brake

A parking brake for a commercial vehicle equipped with an air-operated service brake is configured in such a way that the actuating energy for the brake is reduced in comparison to a configuration with a spring brake cylinder, while the installation space in the wheel area is minimized. Primary functional parts of the parking brake include an inner race and an outer race, which delimit an annular gap. Displaceable tapered-roller bearings are located in the annular gap. To adopt a release position in opposition to the action of a compression spring, the tapered roller bearings are disengaged from the conical surfaces of the inner race and the outer race.