US Patent 7641077 Pump dispensers

Certain pump dispensers, for example foam dispensers, are specially adapted for inverted use. One feature especially useful in a foam dispenser having both an air cylinder and a liquid cylinder with respective pistons is an intake conduit arrangement to increase the clearance of liquid from the container. An intermediate shell fits over the upright liquid cylinder body and carries an inlet valve positively urged upward to the closed position to prevent leaking. A conduit shell fits over the intermediate shell and creates an intake conduit extending down the side of the liquid cylinder to an intake opening lower down the pump body.