| 摘要 |
<p>804,897. Valves. BOULTON-PAUL AIRCRAFT, Ltd. Jan. 2,1957, No. 171/57. Class 135. The casing of a rotary cylindrical valve is provided with a pair of supply and exhaust ports PI, P0, respectively, a pair of ports A1 connected to one side of an hydraulic actuator, and a further pair of ports A2 communicating with the other side of the actuator; two pairs of concave grooves C, D, in the valve member are arranged so that whilst either pair of ports A1 or A2 is supplied with fluid through ports PI only one of the other pair of these ports is connected to its associated exhaust port P0. The angle between the ports P0 and A1 or A2 is preferably less than that between the latter and ports P1. The grooves C and D are formed by an arc with a depth of 11 and 10 per cent, respectively, of the chord.</p> |
