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. 13, 1979
Filed:
Aug. 08, 1977
Kunio Miyashita, Hitachi, JP;
Hironori Okuda, Hitachi, JP;
Seizi Yamashita, Katsuta, JP;
Shoji Tanabe, Sakura, JP;
Hitachi, Ltd., , JP;
Abstract
A rotor of a permanent magnet type synchronous motor comprises a rotary shaft, a rotary supported by the rotary shaft and including an alternate disposition of a core section in the form of a lamination of a magnetic material which is stacked in the axial direction and a reinforcement section of a non-magnetic material and cavities axially formed in the core and reinforcement sections by passing therethrough, permanent magnets received in the cavities, and a strap interposed at least between the radial outer surface of respective permanent magnets and the opposing inner wall of the cavity, whereby distribution of pressures resulting from a centrifugal force due to the rotation of the rotor, which pressures are imparted on the inner wall of the cavity by the outer surface of the permanent magnet, is uniformed or shared by the strap, thereby preventing the permanent magnet from being fractured.