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. 03, 2001
Filed:
Sep. 17, 1999
Ravi Ramanathan, Midland, MI (US);
Robert E. Wrisley, Clare, MI (US);
Thomas J. Parsons, Freeland, MI (US);
Kun S. Hyun, Midland, MI (US);
The Dow Chemical Company, Midland, MI (US);
Abstract
A gear pump exhibiting improved efficiency over a broader range of fluid viscosity and pump speed includes a compression zone defined between each of a pair of pump gears and internal walls of a gear chamber, wherein the compression zones have a non-uniform thickness along a longitudinal direction of the gears. The geometry of the compression zones provides a mechanism whereby the drag of the viscous fluid which is induced by the rotation of the pump gears carries the viscous fluid through a progressively narrower gap in the direction of rotation ending in a final smooth pinch-off at the start of the seal zone. The geometry of the compression zone maximizes the drag and pressurization of the viscous fluid being pumped into the teeth of the gears, thereby assisting in the complete filling of the teeth. The result is improved fill efficiency over a broader range of pump speeds and over a broader range of fluid viscosity.