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:
May. 10, 2005
Filed:
Mar. 10, 2004
Daisuke Ogata, Itami, JP;
Naoki Inui, Itami, JP;
Shinya Arinaga, Itami, JP;
Harumitsu Sasaki, Itami, JP;
Daisuke Ogata, Itami, JP;
Naoki Inui, Itami, JP;
Shinya Arinaga, Itami, JP;
Harumitsu Sasaki, Itami, JP;
Sumitomo Electric Industries, Ltd., Osaka, JP;
Abstract
A noise-reduced internal gear pump incorporating an inner rotor having an addendum formed by a smooth curve and a dedendum formed by a hypocycloid. The tooth profile of the outer rotor is determined by the following steps. The center Oi of an inner rotoris revolved around the center Oo of the outer rotor so as to form a circle S having a diameter of 2e+t, where 'e' is the amount of eccentricity between the inner and outer rotors and 't' is the maximum value of the interrotor clearance between the outer rotor and the inner rotor pressed against it. The inner rotoris rotated on its axis 1/n times while its center Oi makes one revolution in the circular orbit S, where “n” is the number of teeth of the inner rotor. The envelope of the group of the tooth profile-curves of the inner rotor formed by its revolution is used as the tooth profile of the outer rotor.