Abstract: A valve for pumping a viscous fluid from a holding container includes a valve body having a fluid chamber, and a piston displaceable in the fluid chamber for pumping fluid from the fluid chamber through an outlet openings. The piston is attached to the end of a shaft which extends out of the valve. A hub with a plurality of openings and a resilient washer on its peripheral edge are slidably located on the shaft in the fluid chamber. When the piston is in contact with the hub it blocks the flow of fluid through the opening. When the hub is axially displaced from the piston, fluid is allowed to flow through the openings. Depression of the plunger causes movement of the piston away from the hub because of frontal engagement of the resilient washer with the walls of the fluid chamber. This allows the fluid to flow around the piston. Further movement of the shaft causes a projection on the shaft to engage the hub.

Abstract: A valve for pumping fluid includes a valve body and a valve chamber in the valve body. The valve body has a first end with an entrance passage therethrough. The entrance passage communicates with the chamber to provide a passage for the flow of fluid through the container to the valve chamber. A plunger and a piston are provided. The piston is within the chamber and is connected to the plunger. The piston is moveable in the chamber in response to depression of the plunger. A seat is in the chamber as is a flexible washer. The flexible washer is adjacent to the piston and movable therewith. A biasing spring is provided in the valve body for biasing the washer against the seat. A spout is provided. An exit passage which extends between the spout and the chamber is provided and this exit passage is sealed by the washer when the washer is in the seated position. A normally closed check valve is between the chamber and the entrance passage.