Patent ID: 6048186
Filing Date: 2000-04-11
Classification: G01F

Abstract:
In a driving pump or flow meter, the combination of a first gear and second gear identical to each other and both mounted for rotation about their centers and operatively positioned with their teeth in centers and operatively positioned with their teeth in mesh for all angular positions;each of said gears being of modified elliptical form such that a pitch line of each gear in a region of a minor axis extends closer to the center than a true ellipse pitch line and a pitch line of each gear in a region of a major axis extends closer to the center than said true ellipse pitch line; andsaid first and second gears functioning as impellers to drive fluid through said pump or flow meter;a gear shape form side facing the major axis being an involute form, and a gear shape form side facing the minor axis being a cycloid gear form.