Patent ID: 6575431
Filing Date: 2003-06-10
Classification: F16K

Abstract:
A weir type diaphragm valve comprising:(a) a valve body having an inlet end, an outlet end and an internal flow path therebetween, the valve body including a weir disposed transverse to the flow path, the weir having upstream face, a downstream face and a top edge, the top edge defining an elongate valve seat, the top edge comprising a lower surface and a raised bead disposed above the lower surface and running along substantially the entire length of the top edge, the raised bead having an arcuate top surface with a radius of curvature measured at the central vertical cross-section which is less than the radii of curvature in the lower surface and in the downstream lower surface measured at the central vertical cross-section; (b) a flexible diaphragm disposed above the valve seat, the diaphragm being flexible between a closed diaphragm position wherein the diaphragm is in tight abutment with the valve seat so that the flow path is sealed closed and an open diaphragm position wherein the diaphragm is spaced apart from the valve seat so that the flow path is open; and (c) a valve stem and handle assembly for alternatively flexing the diaphragm between the closed diaphragm position and the open diaphragm position.