| 摘要 |
<p>Valve means for governing the flow of fluid to, and possibly also from a consumer, has a housing enclosing a movable main valve member, actuable by pressure fluid operable servo means. A flow control valve in a conduit supplying pressure fluid to the flow control valve is governed by an electric resistance body, e.g. a resistance wire, included in an electric circuit. By controlling the flow of electric current through the circuit the position of the main valve member may be determined within close limits. When the main fluid to be governed is pressurized the fluid acting upon the servo means may be branched off from the main flow.</p> |
