Product dispenser and valve therefor

Claim 1

A product dispenser comprising; a rigid enclosure bounding an internal cavity; a removable closure on said enclosure to give access to said cavity; a flexible, product-containing liner in said cavity; a passage from said liner to the outside of said enclosure; valve means in said passage controlling flow of product through said passage said valve means comprising a housing having a passage therethrough, an opening in an end thereof, a control stem slidably disposed in said passage having an interior product passage and ports extending therethrough, the housing and the control stem each having a conical face, and a flexible seal disposed between the two said faces and facing said ports, the flexible seal being attached to the housing adjacent to the said opening, and to the control stem on the opposite side of said opening from the said ports; and a self-contained, flexible, expansible and compressible pressure source in said cavity, outside the liner, and not obstructing the passage, said pressure source comprising a hollow structure whose volume can change and a charge wholly contained within said structure of a material which is condensable at temperatures provided in household freezers; and gaseous at ordinary household temperatures.