Patent ID: 7063304

Claim:
A diaphragm valve comprising: a valve body defining an inlet passage, an outlet passage, and a fluid chamber with an inner wall and an open side, each of said inlet passage and said outlet passage forming an opening in said inner wall so that said inlet passage, said outlet passage and said fluid chamber are fluidly communicable with each other; a valve seat portion surrounding the inlet passage opening in the fluid chamber; a flexible diaphragm assembly sealingly closing the open side of said fluid chamber and having a valve portion facing into said fluid chamber, said flexible diaphragm assembly selectively shiftable between at least a valve closed position wherein said valve portion is sealingly engaged with said valve seat portion to block fluid flow through said valve, and a valve open position wherein said valve portion is spaced apart from said valve seat to enable fluid flow through said valve, said flexible diaphragm assembly including a primary diaphragm assembly comprising a primary diaphragm member presenting a pair of opposing surfaces and being formed from thin fatigue resistant fluoropolymer material, and a diaphragm backer member contiguous and substantially coextensive with one of the pair of opposing surfaces of the primary diaphragm member, the diaphragm backer member formed from thin high strength fluoropolymer material, said flexible diaphragm assembly further including a secondary diaphragm spaced apart from said primary diaphragm assembly; and an actuator assembly operably coupled with said flexible diaphragm assembly for selectively positioning said flexible diaphragm assembly in each of said valve open and said valve closed positions.