Patent ID: 7861895

Claim:
A foam pump comprising: (a) a pump housing having a liquid chamber and an air chamber, said liquid chamber being in fluid communication with a foamable liquid filled container, and said air chamber being in fluid communication with a high pressure air source through an air inlet; (b) a dispensing tube partially disposed within said pump housing having a wiper seal post with a closed distal end positioned within said pump housing, and an outlet tube with an open distal end positioned outside said pump housing, said wiper seal post including at least one inlet hole in fluid communication with said liquid chamber, and a check valve near said second open end; (c) at least one foam screen located in said open end of said outlet tube; (d) a wiper seal slidably and coaxially positioned around said wiper seal post, said wiper seal being in sealing contact with an inner wall of said pump housing and with said wiper seal post; and (e) a spring bias positioned within said pump housing to bias said wiper seal in an unactuated position; wherein said wiper seal forms a movable barrier between said liquid chamber and said air chamber and wherein said wiper seal is adapted to slide axially along said wiper seal post away from said outlet tube and past said at least one inlet hole when actuated by high pressure air, thereby allowing said high pressure air to enter said dispenser tube and cause mixing of said air and foamable liquid within said dispensing tube and causing expulsion of said mixture through said check valve and said at least one foam screen.