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:
Apr. 23, 1985
Filed:
Aug. 23, 1982
Donald D Foster, Kingsville, MO (US);
Other;
Abstract
When the reciprocable plunger of the pump is locked down in its fully depressed position, the lowermost tip of the plunger maintains the inlet ball check valve of the pump forcefully pressed against its seat to prevent leakage. Spindly legs on the hollow plunger adjacent the tip thereof define inlet orifices for the discharge passage of the plunger during operation and provide a spring-like action for generating the ball hold down force. As the tip engages the ball valve and the plunger is rotated slightly during the lock down, the lowermost cylindrical portion of the plunger is centered on the ball and held against rotation by the resilient legs and a trio of guiding projections arranged in the lower end of the pump chamber about the cylindrical portion. Consequently, the legs have a tendency to wind up torsionally as well as bow resiliently outwardly to thereby compound the resistance of the plunger to unseating movement by the ball.