Patent ID: 8616414

Claim:
A foam dispenser: a container retaining a foamable liquid for dispensing; a reciprocating piston liquid pump having a reciprocating piston with a pump outlet, said reciprocating piston liquid pump communicating with said foamable liquid in said container, said reciprocating piston liquid pump being actuated by reciprocation of the reciprocating piston to dispense a dose of foamable liquid at said pump outlet; a holding chamber membrane defined by a floor, a cover, and a sidewall and surrounding said reciprocating piston, said reciprocating piston liquid pump extending through said floor of said holding chamber membrane; a separation membrane positioned between said reciprocating piston and said holding chamber membrane to define a holding chamber between said separation membrane and said holding chamber membrane, said separation membrane surrounding said reciprocating piston so as to permit a dose of foamable liquid dispensed at said pump outlet of said reciprocating piston to enter said holding chamber and collect on said floor, said cover being biased away from said floor to establish an expanded volume of said holding chamber, and movable toward said floor to establish a compressed volume of said holding chamber; a dispensing spout having a spout inlet communicating with said holding chamber proximate said floor and extending to a spout outlet; a foam media in said dispensing spout between said spout inlet and said spout outlet, wherein, when said cover is moved sufficiently toward said floor, said reciprocating piston liquid pump is actuated and dispenses a dose of foamable liquid into said holding chamber, and the volume of said holding chamber decreases, forcing air and foamable liquid into and through the dispensing spout and foam media to said spout outlet.