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:
Dec. 27, 1977
Filed:
Apr. 07, 1976
Wallace Farnholm Magers, Leawood, KS (US);
Larry Lee Hudson, Lee's Summit, MO (US);
James Phillip Workman, Lee's Summit, MO (US);
Realex Corporation, Kansas City, MO (US);
Abstract
The reciprocable plunger of the pump has a valve sleeve which circumscribes the plunger and shifts relative to the latter between port opening and port closing positions in response to telescopic depression and extension of the plunger within its receiving barrel. That portion of the plunger circumscribed by the sleeve is necked down and provided with the port that communicates the discharge passage of the plunger with liquid in the barrel. The sleeve is generally hyperbolic in longitudinal cross-section, having an inner surface which is generally complimentally received within the neck of the plunger. A pair of radially outwardly extending, annular steps in such inner surface on opposite sides of the port define a pair of corresponding shoulders on the inner surface that are disposed to engage oppositely tapering sections of the plunger neck during movement of the sleeve between its port opening and port closing positions, thereby to effect such opening and closing of the port. The plunger is of two part construction at its neck, having a detachable tip that serves as a retainer for the sleeve and which is symmetrically constructed so that it may be inverted end-for-end during assembly without adversely affecting the operation of the pump.