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:
Mar. 31, 1998
Filed:
Jul. 12, 1995
Jack G Sundberg, Meriden, CT (US);
Coltec Industries Inc., New York, NY (US);
Abstract
A novel single acting variable displacement vane pump (VDVP) incorporating novel vanes and undervane venting which produce selective regulated pressure-loading of the vanes against the cam surface and more positive tracking in the incoming seal arc and the outgoing or discharge seal arc of the pump rather than uniform pressure balancing of the vanes throughout the 360.degree. cam chamber. The vanes incorporated into the present pumps preferably are sectional two-piece vane assemblies comprising an upper vane section which slidably supports a lower vane section and incorporates a fluid pressurizable cavity between said vane sections which, when pressurized, forces the vane sections in opposite radial directions, and which enables the vane sections to come together and integrate when the cavity is depressurized. The vane cavity is open to the fluid pressure on one side of the vanes while the undervane area of the vane slots, below the vanes, is open to the fluid pressure one the opposite side of the vanes. Thus, in the inlet seal arc area of the pump the vane cavity becomes pressurized to force the vane sections apart and force the upper vane section against the cam surface, and in the outlet or discharge seal arc area of the pump the vane cavity becomes depressurized and the undervane area of each vane slot becomes pressurized, to force the vane sections together and force the upper vane section against the cam surface.