Patent ID: 6644516
Filing Date: 2003-11-11
Classification: B05B,G01F

Abstract:
A foaming liquid dispenser comprising:a pump housing having a liquid pump chamber with a cylindrical interior surface and an air pump chamber with a cylindrical interior surface; a pump plunger in the pump housing, the plunger having an interior discharge passage extending through the plunger; a liquid pump piston and an air pump piston on the plunger, the liquid pump piston and the air pump piston being mounted in the respective liquid pump chamber and the air pump chamber for reciprocating movement between charge and discharge positions of the liquid pump piston and the air pump piston in the respective liquid pump chamber and the air pump chamber, where in the charge positions the liquid pump piston and air pump piston each engage with the respective liquid pump chamber interior surface and air pump chamber interior surface and in the discharge positions the liquid pump piston engages with the liquid pump chamber interior surface and the air pump piston at least partially disengages from the air pump chamber interior surface.