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:
Jan. 06, 1998
Filed:
Mar. 03, 1997
Paul A Johnson, Vancouver, WA (US);
Micropump Corporation, Vancouver, WA (US);
Abstract
A pump housing is provided with a conduit extending through the housing between a pump inlet and pump outlet. A pump device is disposed within the housing and in communication with the conduit to pump fluid therethrough. A fluid flow meter also is disposed within the housing and in communication with the conduit to monitor fluid flow rate through the conduit. The fluid flow meter generates signals related to the fluid flow rate which are fed back to a control device operable to control the flow rate through the pump device. The flow meter may include a pair of meshed modified elliptical gears. The modified elliptical gears are based on a true elliptical shape, with bulged portions added between the major and minor axes of the elliptical shape. The modified elliptical gears have involute teeth that are relatively thick adjacent the minor axis and relatively thin adjacent the major axis.