DIAPHRAGM FOAM PUMP FOR FOAM DISPENSERS AND REFILL UNITS

摘要

A refill unit for a foam dispenser including a liquid container and a diaphragm foam pump connected to the liquid container and diaphragm foam pumps. The diaphragm foam pump includes an elastomeric diaphragm having an air piston bore and a bellows. The air piston bore forms at least a portion of an air chamber. A reservoir is located at least partially within the bellows that includes a liquid inlet. The diaphragm foam pump includes a piston that forms a portion of the air chamber wherein the piston bore may be moved relative to the piston. Movement in a first direction causes air in an air chamber to be compressed and draws liquid into the reservoir and further movement in the same direction causes compressed air to flow into the reservoir where it mixes with the liquid and is expelled as a foam.