Pull pumps, refill units and dispensers for pull pumps

摘要

Dispensers, refill units and pumps are disclosed herein. The refill units include a container secured to a pump. Some exemplary refill units for dispensers include a container for holding a liquid and a post seal pump. As the post seal pump operates, a piston moves up and down over the pump seal. When the piston shaft is in a first position, fluid flows into the pump chamber and one or more apertures through the piston shaft are sealed off by the post seal. When the piston shaft is in a second position, the piston engages a wall of the pump chamber and the one or more apertures are away from the post seal to provide a fluid path from the pump chamber to the interior of the hollow piston shaft and is dispensed through an output.

主权项

1. A refill unit for a liquid dispenser comprising:
a container for holding a liquid; and a post seal pump;
the post seal pump comprising
a housing;the housing secured to the container;a post secured to the housing;a post seal on the post;the housing having a pump chamber;a base at one end of the pump chamber;an aperture through the base;a shaft seal secured to the housing and located proximate the aperture in the base;a hollow piston shaft having a first end that fits over the post and engages the post seal and a second end that reciprocates within the aperture;a fluid outlet located proximate the second end of the hollow piston shaft;a piston located at an intermediary position on the shaft;one or more apertures through the piston shaft located between the piston and the fluid outlet;wherein when the piston shaft is in a first position, fluid flows into the pump chamber and the one or more apertures through the piston shaft are sealed off by the post seal; andwherein when the piston shaft is in a second position, the piston engages a wall of the pump chamber and the one or more apertures provide a fluid path from the pump chamber to the interior of the hollow piston shaft.