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. 04, 1984
Filed:
Apr. 15, 1982
Michael D Davis, Coldwater, MI (US);
Eaton Corporation, Cleveland, OH (US);
Abstract
A rotary hydraulic vane pump is disclosed of the type including a cam ring (19) defining an internal cam surface (21). The pump also includes a rotor (25) which defines a plurality of slots (27) which receive roller vanes (29). The internal cam surface includes a discharge arc surface portion (65) which is the cam fall portion of the cam surface. In one aspect of the invention, it is recognized that flow turbulence, pressure pulses and noise is caused by a slight net increase in the volume of a contracting fluid chamber (57) during cam fall, and that this increase is caused by radially inward movement of the roller vane during cam fall. In another aspect of the invention, the discharge port (59) is located such that fluid communication between the contracting fluid chamber and the discharge port does not occur until after the net increase in the volume of the contracting fluid chamber has ceased, and a net decrease in the volume of the chamber has begun.