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. 23, 2013
Filed:
May. 23, 2008
Seigo Ono, Shinjyuku-ku, JP;
Katsuichi Uchida, Shinjyuku-ku, JP;
Seigo Ono, Shinjyuku-ku, JP;
Katsuichi Uchida, Shinjyuku-ku, JP;
Oval Corporation, Tokyo, JP;
Abstract
Flowmeter with a pair of helical gears using an oval pitch curve as a reference rack tooth profile. The tooth height ratio of the reference rack tooth profile is π/4. The reference rack tooth profile is an oval pitch curve of two or less leaves. The moving radius of the oval pitch curve is expressed by ρ=a/(1−b cos nθ), where ρ is a moving radius which is a distance between the center of rotation and the oval pitch curve, 'a' is a similarity factor, 'b' is a degree of flatness, n (n≦2) is the number of leaves, and θ is an argument. The tooth height ratio is h=a/(1−b)−g, where gis a distance between poles of the oval pitch curve and pitch line, wherein g=a cos θ/(1−b cos nθ). Values for the similarity factor “a”, degree of flatness “b”, and distance gare determined so that the tooth height ratio may be πm/4.