The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
May. 31, 1994
Filed:
Jan. 25, 1993
James L Drobish, Wyoming, OH (US);
Frank A Ciboch, Jr, Forest Park, OH (US);
Robert A Paul, Fairfield, OH (US);
Jimmy C Edwards, Cincinnati, OH (US);
Lawrence E Robbins, Hamilton, OH (US);
The Procter & Gamble Company, Cincinnati, OH (US);
Abstract
The present invention presents an improved pump piston for pressurizing liquid dispensing containers, and more particularly improved air inlet valve designs for such pistons. According to the present invention, the inlet valves are located remotely from the lower end of the pump piston, such that they are protected from contamination by liquid product and resulting degradation of performance. One inlet valve design utilizes a lost motion connection between the pump piston and upper cap, with structural elements of the upper cap and piston cooperating to form an inlet valve that is opened to admit air into the interior of the piston when the cap is pulled upward and tightly sealed when the cap is pushed downward. Another inlet valve design utilizes slits in the wall of the piston itself and the flexibility of the piston material to form an inlet valve that is opened to admit air into the interior of the piston when the cap is pulled upward and tightly sealed when the cap is pushed downward. The lost motion design is disclosed in two possible embodiments, and a number of versions of the valve slit embodiment are disclosed.