| 摘要 |
948,243. Valves. VEREINIGTE ARMATUREN-G.m.b.H. Aug. 30, 1962 [Sept. 20, 1961], No. 33398/62. Heading F2V. A fluid actuated flexible sleeve valve comprises a flexible sleeve 105 which closes on an insert 106 in response to fluid pressure supplied through ports 117. A fluid pressure actuator comprises a differential piston 110 having its larger face 111 subjected to pressure of fluid flowing through the valve by passage 159, its smaller face 115 adjoining the space 116 from which the ports 117 lead, the space 116 being filled with liquid and its stepped face 119 being subjected to the pressure in space 120 to which a control fluid is supplied and exhausted through pipe 121 under the control of a three way valve. In a modification, two such annular pistons are provided having their larger faces opening to a common space. The control fluid may be the fluid flowing through the valve or a separate fluid. A rod 132 extends from the larger face to reduce the effective area of this face and to provide an indicator to show the position of the valve. In the event of failure of the control pressure, the valve is moved to the closed position. |
