CLOSED POSITION MAINTAINABLE SELECTOR VALVE, KNEE TORQUE DEVICE USING THE VALVE, AND ARTIFICIAL LEG

摘要

A selector valve capable of maintaining a closed position for a while even if an operating force to a valve element (80) is eliminated when the selector valve (10) is switched from a closed position (braking state) to an open position. The valve element (80) of the selector valve (10) receives an operating force from the outside and a returning force in the opposite direction of the operating force by a valve spring (90). Accordingly, the valve element (80) opens and closes the valve by making the first end (801) of the valve element (80) seat on/unseat from a valve seat (48) on the housing (20) side according to the presence or absence of the operating force. A first port (31) and a second port (32) on both sides of the valve seat (48) are connected or cut off from each other by the opening and closing. The valve element (80) is formed in a stepped structure, and receives a force based on a difference in pressure receiving area by the stepped structure which results from the pressure of hydraulic fluid. The force can maintain the closed position of the valve for a while.