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:
Jul. 28, 2015
Filed:
Dec. 26, 2012
Sumitomo Electric Sintered Alloy, Ltd., Takahashi-shi, Okayama, JP;
Masato Uozumi, Itami, JP;
Toshiyuki Kosuge, Itami, JP;
SUMITOMO ELECTRIC SINTERED ALLOY, LTD., Okayama, JP;
Abstract
In an internal gear pump, a diameter of a base circle is set to A mm, a radius of a rolling circle is set to b mm, a diameter of a locus circle is set to C mm, and an amount of eccentricity is set to e mm. A trochoidal curve T is drawn by rolling the rolling circle along the base circle without slipping and by using a locus of a fixed point distant from a center of the rolling circle by e. A tooth profile of an inner rotorhaving n teeth is formed based on an envelope of a group of the locus circles each having a center on the trochoidal curve T. A pump rotoris formed by combining the inner rotor with an outer rotor having (n+1) teeth. A tooth-profile curve of the inner rotor satisfies the following expression (1). Because K<1 is satisfied, cusps s are not formed at opposite edges of each addendum of the inner rotor.