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:
Oct. 13, 1992
Filed:
Jul. 26, 1990
Masakatsu Tanaka, Katsuta, JP;
Masanobu Itoh, Katsuta, JP;
Toshihiko Nara, Katsuta, JP;
Tasuhiko Takahashi, Ibaraki, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
An electromagnetic disc brake for an elevator lifting apparatus comprises a disc spline-coupled with a rotational shaft. Braking body and an armature disposed to clamp the disc; braking springs press the armature against the disc, and an iron core is provided which includes inner and outer magnetic poles each facing the armature and concentrically formed with respect to the rotational shaft. An electromagnetic coil generates magnetic flux to pass through the inner and outer magnetic poles as magnetic paths. In addition, at least one of the pole face of the outer magnetic pole and the facing portion of the armature where it faces the pole face is provided with an arrangement for increasing a magnetic gap, and the braking springs are disposed in portions of the outer magnetic pole. Further, the braking body is supported through a sound absorbing member or one side of the armature facing the disc is formed of a sound absorbing member.