Abstract: A diaphragm operated valve having the diaphragm attached at its lower end to a valve closure plug, and movable therewith, and attached at its upper end to a portion of valve body that forms the pressure cavity. The diaphragm has a stepped portion between its upper and lower ends which folds back on itself when the valve opens. The valve body has shoulder portions that support the diaphragm when the valve is closed to avoid stressing the diaphragm material due to pressure in the pressure chamber. This allows the outside diameter of the diaphragm to be minimized, and eliminates the need for fabric reinforcement. A filter screen is positioned flush with the surface of the valve plug so that high velocity flow across the screen while the valve is opening and closing removes accumulated dirt thereby making the screen self cleaning.

Abstract: A flow shut off or throttling valve is provided in a sprinkler nozzle housing to enable a nozzle to be changed without having to turn off a flow pressure source. The valve intersects a flow path through the nozzle housing and has an opening such that when the opening is aligned with the flow path, a flow stream can flow unobstructed through the flow path. The valve is movable between a fully open position in which the opening is aligned with the flow path and a closed position which blocks the flow stream from flowing to a nozzle disposed at an outlet passage of the flow path. The valve may be constructed to be either slidable or rotatable between the two positions, and is actuated by a gearing arrangement which is operable at the exterior of the nozzle housing. The external valve actuator may function as a physical barrier to retain the removable nozzle in the nozzle housing when the valve is open and to disengage the nozzle when the valve is closed.