Abstract: The present invention provides a diaphragm valve moveable between a fully open position and a fully closed position, the valve comprising: a bonnet having a first thread and an abutment surface; a stem having at least one aperture and a second thread that cooperates with the first thread to allow the stem to be axially moveable relative to the bonnet; a handwheel being freely rotatable on the stem and freely axially slidable on the stem and having a stop with a surface for contacting the abutment surface of the bonnet; and a pin extending through the handwheel and into the at least one aperture in the stem for limiting rotary motion of the handwheel relative to the stem. In one aspect of the invention, the at least one aperture is a slot. In another aspect of the invention, the at least one aperture is a plurality of apertures.

Abstract: The present invention provides a diaphragm valve moveable between a fully open position and a fully closed position, the valve comprising: a bonnet having a first thread and an abutment surface; a stem having at least one aperture and a second thread that cooperates with the first thread to allow the stem to be axially moveable relative to the bonnet; a handwheel being freely rotatable on the stem and freely axially slidable on the stem and having a stop with a surface for contacting the abutment surface of the bonnet; and a pin extending through the handwheel and into the at least one aperture in the stem for limiting rotary motion of the handwheel relative to the stem. In one aspect of the invention, the at least one aperture is a slot. In another aspect of the invention, the at least one aperture is a plurality of apertures.