Patent ID: 7537140

Claim:
A device for dispensing liquid soap comprising: a plastic container filled with supply of liquid soap and including a projecting bottom opening threadedly secured to a nut; and a pump mechanism including: a first check valve provided in the opening of the container; a ring member put on the first check valve; a cross-shaped pipe including a top section secured to the first check valve, a projecting bottom section, and a transverse section; a spout secured to the bottom section; a second check valve provided in the spout; an abutment member provided into and secured to the transverse section; a sliding plunger partially inserted into the abutment member and including a forward hollow extension, a rear externally threaded portion, a sealing shoulder between the extension and the externally threaded portion, and an adjustment ring threadedly put on the externally threaded portion; a spring biased between a bottom of the extension and a closed end of the transverse section; and a cap provided on an outer end of the plunger; wherein in an inoperative position the second check valve is closed and the first check valve is open to permit the supply of liquid soap to flow into a space defined by the transverse section and the adjustment ring and store therein, in response to depressing the cap the plunger slides to compress the spring, close the first check valve, and decrease the space for forcing the supply of liquid soap to flow into the bottom section to open the second check valve prior to flowing out of the spout, and in response to removing a depressing force a stored compression energy of the spring pushes the plunger to its inoperative position to create a vacuum in the space, open the first check valve, permit the supply of liquid soap to flow into the space through the first check valve, and close the second check valve at an end of returning the plunger to the inoperative position; wherein the ring member is sealingly engaged with the first check valve in the inoperative position; and wherein the ring member is adapted to wrinkle to permit air to enter the container through the opening in response to a decreased pressure within the container after a predetermined amount of the supply of liquid soap has been dispensed.