Patent ID: 6276658
Filing Date: 2001-08-21
Classification: F16K,G05D,Y10T

Abstract:
In a diaphragm control valve, including:a) a housing having an inlet, an outlet, and a passageway for the flow of liquid from the inlet to the outlet, the passageway surrounded by a valve seat having a seat sealing surface;b) a valve member including a diaphragm within the housing, the diaphragm displaceable towards or away from said valve seat to control the flow therethrough;c) the housing further including a rigid cover between the outlet and passageway, a control chamber is formed between the cover and the diaphragm, and the cover attached to the housing by slotted grillwork surrounding the valve seat;d) the diaphragm includes an outer flexible peripheral section secured to the cover and in alignment with said valve seat, a valve-closure section having a valve sealing surface surrounding a center area, the valve-closure section displaceable with respect to the valve seat for controlling the flow therethrough,e) the valve sealing surface contacting the seat sealing surface when the valve member is fully closed; andf) a pilot valve fluidly connected to the control chamber; an improvement comprising:g) a liquid passageway across the sealing surfaces when the valve is fully closed,h) the slotted grillwork includes vanes, each vane having a diaphragm side and a downstream side and each vane extends from the valve seat to the housing thus forming a slot between adjacent vanes,i) said diaphragm pressed against the diaphragm side of the vanes when fully closed,j) said liquid passageway having a width less than the width of two slots,k) a closure at the vane downstream side of all slots having access to said liquid passageway,l) an opening in each closure, andm) a check valve over the opening.