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:
Jul. 14, 1998
Filed:
Aug. 11, 1997
C Brandon Brown, Jonesboro, AR (US);
Steven W Post, Jonesboro, AR (US);
McNeil (Ohio) Corporation, St. Paul, MN (US);
Abstract
An automatic air operated grease gun comprising a reciprocating grease plunger for ejecting grease, and a piston, connected to the plunger, for operating the plunger. The piston is slidably mounted in a cylinder to move between a retracted position and an advanced position. A return spring resiliently biases the piston to its retracted position. A switch selectively connects the cylinder to a source of gas under pressure to advance the piston against the return spring. The piston has a plurality of apertures therein, each aperture having an individual seal, and a release for opening the individual seals to relieve the pressure behind the cylinder and allow it to retract under the force of the return spring.