Pump having non-throttling peripheral valve

摘要

A dispensing pump is provided with a non-throttling peripheral valve having a circular sealing edge with a diameter of greater than 3/4 inch and a thickness of less than 0.020 inch, and the valve is made of low density plastic material. The result is a pump which will operate at a very low, predetermined actuating pressure. A vent is included in the pump for venting a container to the atmosphere when air pressure in the container becomes reduced.