Patent ID: 7686595
Filing Date: 2010-03-30
Classification: F04B

Abstract:
1. A high pressure metering pump, including: a flexible diaphragm having a concave interior surface and a convex exterior surface; a rigid flat planar surface disposed in opposition to said concave interior surface, said rigid flat planar surface extending across the entire extent of said concave interior surface and forming therebetween a pump chamber; means for connecting a low pressure inlet check valve and a high pressure outlet check valve to said pump chamber; piston means for driving said diaphragm reciprocally toward said rigid flat surface and compress said pump chamber to generate high pressure therein; means for securing the peripheral edge portion of said diaphragm in sealing fashion with said rigid flat planar surface of said pump chamber, said diaphragm having an annular portion spanning between said piston means and said means for securing the peripheral edge portion; mechanical support means for supporting said convex exterior surface of said diaphragm against the high pressure within said pump chamber; said mechanical support means including an annular bushing disposed concentrically about said piston means and impinging continuously on the entire radial and angular extent of said convex exterior surface of said annular portion of said diaphragm, said bushing being formed of an elastic resilient material; further including a high strength metal ring disposed concentrically about said piston means and impinging directly on the radial extent of said annular bushing to support said annular bushing and said convex exterior surface of said annular portion of said diaphragm against the high pressure generated in said pump chamber.