Patent ID: 6390791
Filing Date: 2002-05-21
Classification: F04B

Abstract:
A fluid flow device comprising a first plate, a second plate, an intermediate plate disposed between said first and second plates, a pump chamber defined by said first plate and said intermediate plate, an inlet control member and an outlet control member communicating with said pump chamber, said inlet control member being provided with an inlet duct passing through one of said first and second plates, said outlet control member being provided with an outlet duct passing through one of said first and second plates, said inlet control member being a non-return valve made up of a moving member formed in said intermediate plate and having a first end and a second end, said moving member comprising a membrane-forming portion interposed between the inlet duct and the pump chamber, said membrane-forming portion enabling, by virtue of its resilience, said non-return valve to move between a closed position and an open position, said moving member having an orifice passing therethrough between said first end and second end of said moving member, said non-return valve being shaped in such a manner that, in said open position, the moving member does not prevent liquid from flowing from said orifice towards said pump chamber, and said second end of said moving member being shaped in such a manner that, in said closed position, it provides sealed contact with that one of the first and second plates that forms the seat of the non-return valve,wherein said moving member is situated in the major portion of the thickness of the intermediate plate, wherein said membrane-forming portion is situated closer to the other one of the first and second plates that does not form the seat of the non-return valve than to the one of the first and second plates that forms the seat of the non-return valve, and in that said orifice presents a volume that is less than the volume of the pump chamber.