| 摘要 |
PURPOSE:To make a lock releasing device capable of releasing a locked state before a servo valve is operated, by utilizing the output oil pressure of a master cylinder, when a spool valve is locked at its closure by the pressure difference between an intake port and an exhaust port, in the servo valve composed of an electrical actuator and a spool valve. CONSTITUTION:A valve casing 25 for a spool valve 22 comprises an operating fluid chamber 29 faced by the upper end surface of a valve body 23, an output chamber 34 communicating with the operating fluid chamber 29, and pressurized by a piston 35 advancing in response to the output oil pressure of a master cylinder M, a valve means 31 for releasing the output chamber 34 to a reservoir 11, after the valve body 23 is forcibly moved by a minute displacement by a pressure increase in the operating fluid chamber 29. |
