Patent ID: 8591207

Claim:
A reciprocating piston pump for use in an inverted position comprising: a liquid chamber defined in part by a liquid chamber sidewall extending in an axial direction; a liquid piston in said liquid chamber, wherein said piston reciprocates in said axial direction to actuate the pump and refill said liquid chamber, the axial movement of said liquid piston in one direction resulting in the intake of liquid from a liquid source into said liquid chamber, and the axial movement of said liquid piston in an opposite direction resulting in the expulsion of liquid from said liquid chamber; a liquid chamber inlet extending through said liquid chamber sidewall, wherein the intake of liquid resulting from movement of said liquid piston occurs at said liquid chamber inlet, an elastomeric valve positioned within said liquid chamber, wherein said liquid piston is moved to expel liquid from the liquid chamber, said elastomeric valve covers said liquid chamber inlet in a sealing engagement therewith, and, when the liquid piston is moved to intake liquid from said container into said liquid chamber, said elastomeric valve is drawn off of said liquid chamber inlet, out of sealing engagement therewith, and an air pump wherein actuation of the air pump in a first direction causes air to enter into an air pump chamber through an air intake port and actuation of the air pump in a second direction causes air to exit the air pump into a mixing chamber wherein the air and the liquid from the liquid chamber are mixed together and the mixture flows through a mixing medium and is dispensed as a foam out of a dispensing outlet.