Patent ID: 9683676
Date: 2017-06-20
CPC Classifications: F16K,Y10T

Claim:
1. A valve with proof of closure, the valve comprising: a valve body comprising a first port and a second port separated by a valve member that is biased toward a closed position; a pressure chamber having a pressurized fluid port for connecting to a source of pressurized fluid; a piston mounted within the pressure chamber; a control member attached to the valve member; wherein: the piston biased toward a retracted position, where the piston is disengaged from the control member, and the piston moving to an extended position where the piston engages the control member, in response to pressurized fluid entering through the pressurized fluid port; the piston in the retracted position being spaced a first distance from the control member, the piston is moved the first distance in a first direction from the retracted position toward the extended position such that the piston engages the control member after the piston has moved the first distance; and further movement of the piston in the first direction moves the valve body from the closed position toward an open position; a valve position indicator having a closed state and an open state, the valve position indicator being biased toward the closed state, the valve position indicator being actuated by the piston as the piston is moved a second distance in the first direction from the retracted position toward the extended position to move the valve position indicator from the closed state toward the open state, and the second distance being less than or equal to the first distance.