Patent ID: 8038231

Claim:
A control valve comprising: a housing having a movable element therein movable between first and second positions along a linear axis in response to fluid pressure acting on at least one of opposite ends of said movable element; an interlock element supported by said housing and movable substantially perpendicular to the axis along which said movable element moves; one end of said movable element having an extension extending therefrom for a greater distance than the travel distance of said movable element in the direction in which the extension extends; said interlock element being movable between a first position to which it is biased by a biasing force and a second position to which it is moved when the biasing force on said interlock element is removed; said interlock element retaining said movable element in its first position when said interlock element is in its first position to prevent movement of said movable element from its first position; and said interlock element ceasing to prevent movement of said movable element when said interlock element is moved to its second position so that said movable element can be moved to its second position.