Patent ID: 8529235

Claim:
A pump, comprising: a) a housing comprising an exterior surface and an enclosed interior chamber with a sidewall, the chamber substantially circular in cross-section; b) an inlet port providing communication between the exterior surface and the interior chamber; c) an outlet port providing communication between the exterior surface and the interior chamber; d) a rotatable crank assembly comprising a longitudinal axis rotatably disposed within said housing wherein the longitudinal axis is coaxially aligned with the center of the circular cross-section of the interior chamber; e) a spacer support operatively connected to the crank assembly, the spacer support disposed within the interior chamber, the spacer support further comprising a spacer pin; f) an annular spacer rotatably disposed on the spacer pin; g) an annular ring disposed in the interior chamber, the annular ring further comprising a ring sidewall disposed between the annular spacer and the interior chamber sidewall, the ring sidewall having a width being the same as a minimum distance separating the annular spacer and the interior chamber sidewall; and h) a slider valve slidably disposed in the housing, the slider valve configured to maintain contact with the ring as the crank assembly is rotating thereby isolating the inlet port from the outlet port.