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:
Mar. 18, 2014
Filed:
Jan. 19, 2012
Takehito Tamaoka, Kyoto, JP;
Kazushi Miura, Kyoto, JP;
Mitsuhiro Takemoto, Kyoto, JP;
Nidec Corporation, Kyoto, JP;
Abstract
A motor includes a stationary portion and a rotating portion. The rotating portion includes a sleeve portion including one communicating hole arranged to extend completely there through from an upper surface to a lower surface thereof, and a cover portion including a hole portion. The axial extension range of the hole portion is arranged to overlap with the axial extension range of the communicating hole in a radial direction. A center of the hole portion is arranged on a plane including a central axis and a center of the communicating hole. The communicating hole and the hole portion are arranged on opposite sides of the central axis. The following inequality is satisfied: V<(σ/σ)·V, where σis the density of the sleeve portion, Vis the volume of the communicating hole, σis the density of the cover portion, and Vis the volume of the hole portion.