PARKING BRAKE DEVICE

摘要

A parking brake device, wherein the parking brake state of a wheel brake is provided by the advancing operation of a parking piston (44) slidably fitted to a casing (23) with its rear surface side facing a control fluid pressure chamber (47) for parking, an opening part (112) forming a part of a lock mechanism (31) mechanically locking the advanced state of the parking piston (44) and formed in the casing (23) at a portion facing the rear surface of a lock piston (56) slidably fitted to the casing (23) on the rear side of the parking piston (44) and energized forward by a spring is closed by a detachable cover member (113). A tool connection part (115) allowing a tool inserted from the opening part (112) to be detachably connected thereto is formed at the rear of the lock piston (56). Thus, the automatic parking brake state can be provided by a simple structure which does not consume electric power, and the parking brake state can be released by manual operation for maintenance and inspections.