Patent ID: 6848471
Filing Date: 2005-02-01
Classification: B05B,F16K,Y10T

Abstract:
1. A check valve assembly for placement in a fluid conduit within which a pressurized fluid is periodically delivered from a pump to a receiving vessel, and wherein when pressurized fluid is not being delivered the gauge pressure across said check valve will reduce from a positive value to approximately zero or a negative value; said check valve assembly comprising: a cylindrical external housing having an inlet end and an outlet end; a cylindrical internal spigot; and an elastomeric sleeve fitted over said internal spigot; wherein said external housing is adapted to be fitted to a fluid conduit at said outlet end for delivery of a pressurized fluid therefrom to a receiving vessel; wherein said cylindrical internal spigot is sealed at a first, inlet end thereof to said external housing at said inlet end thereof, and is adapted to be fitted to a fluid conduit for delivery of pressurized fluid thereto from a pump; wherein said cylindrical internal spigot extends axially along the interior of said cylindrical external housing from said inlet end thereof towards said outlet end thereof; wherein said cylindrical internal spigot has a radially outwardly directed sloping shoulder formed at a second end thereof near said outlet end, of said external housing, wherein the slope of said shoulder is directed away from said second end towards said first end; wherein said cylindrical internal spigot is sealed at said second end, and has a plurality of radially directed vent apertures formed therein from the interior to the outer periphery thereof, and arranged partially along the length thereof; wherein said elastomeric sleeve is securely fitted to said internal spigot, in the region of said first, inlet end thereof, wherein said elastomeric sleeve has an internal diameter and an elastic memory such that it fits and adheres snugly to the outer periphery of said internal spigot at least in the region thereof where said radially directed vent apertures are located, and over said sloped shoulder; and wherein the elasticity of said elastomeric sleeve is such that it is overcome at a positive gauge pressure between the inlet and outlet ends of said external housing in the range of between 5 and 20 psi; whereby pressurized fluid will flow from said radially directed vent apertures past the periphery of said internal spigot and between the periphery and the internal surface of said elastomeric sleeve towards the outlet end of said external housing when the elasticity of said elastomeric sleeve is overcome, and backflow of fluid at substantially zero or negative gauge pressure between said inlet and outlet ends of said external housing is precluded due to the elastic memory of said elastomeric sleeve as it adheres to the outlet periphery of said internal spigot.