Pump

A dispensing pump and valve assembly for use with a container for liquid comprising, a chamber provided with an inlet to admit liquid from the container past a one-way valve, the chamber having a cylindrical wall, a cap fitted on said chamber, the cap having a portion of its under side spaced from a chamber surface to provide a channel in communication with the interior of the chamber and with the interior of the container, a plunger having a cylindrical stem portion adapted to pass freely through an opening in the cap, an annular flange having a downwardly facing surface, a second cylindrical surface portion adjacent said downwardly facing surface, a plunger base having an upwardly facing annular surface adjacent said second cylindrical surface portion, a longitudinal passage in the plunger, a lateral passage connecting said longitudinal passage with the second cylindrical surface portion, an annular washer of distortable material having a cylindrical inner surface and parallel upper and lower surfaces normal to said inner surface, the height of said inner surface being substantially constant and equal to the height of said second cylindrical surface portion and being less than the width of said washer across any radial section, said washer resting in sealing engagement against at least a portion of said downwardly facing surface, said upwardly facing annular surface and said chamber wall, and a spring biasing the plunger upward to hold the washer in a position to close off said channel.