BRAKE ACTUATOR

摘要

A brake actuator and control valve assembly, the brake actuator (10) having a housing (12) in which is provided a movable assembly (18, 20, 30) including: a brake actuating element (20) which is adapted, in use to be connected to a vehicle brake, the movable assembly (18, 20, 30) being movable from a brake apply position which, in use, results in the application of the brake, and a brake release position which, in use, results in the release of the brake, the brake actuator (10) further including a lock (34, 44, 46) which is operable to change from a locked configuration in which movement of the movable assembly (18, 20, 30) from the brake apply position to the brake release position is prevented, and a released configuration in which movement of the movable assembly (18, 20, 30) from the brake apply position to the brake release position is permitted, wherein the lock (34, 44, 46) includes a fluid pressure operated actuator (34), supply of pressurised fluid to which results in the lock changing from either the locked configuration to the release configuration or vice versa, and the control valve assembly includes an electrically operable lock control valve (100) by means of which supply of pressurised fluid to the lock actuator (34) is controlled, the lock control valve (100) having an inlet port (100a) which is connected to a source of pressurised fluid (80), a delivery port (100b) which is connected to the lock actuator (34) and a valve member which is movable between a first position in which the inlet port (100a) is substantially closed, and a second position in which the inlet port (100a) is connected to the delivery outlet (100b), the valve member being movable between the first and second positions only on the supply of an electrical current to the lock control valve (100).