Patent ID: 7509972

Claim:
A normally closed pneumatic diaphragm valve with mechanical override with lockout for controlling the flow of a fluid, comprising: a housing; a fluid flow passage extending through the housing between a fluid inlet and a fluid outlet; a diaphragm valve movable along an axis to open and close the flow passage; a pneumatic actuator operable to move the diaphragm valve to open and close the flow passage; a manual lockout device rotatable around said axis relative to the housing between a position to enable the valve to be opened by the pneumatic actuator and a position to disable the valve in a position closing the flow passage, the device including a locking member selectively movable to a position preventing rotation of the lockout device from the disabled position; a fitting on the housing to convey a pressurized gas to and from the pneumatic actuator for respectively pressurizing and venting the actuator independently of the position of the manual lockout device.