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:
Apr. 10, 1984
Filed:
Jul. 31, 1981
Applicant:
Inventors:
Nobuo Mitsui, Katsuta, JP;
Yasuyuki Maeda, Katsuta, JP;
Tomiaki Kurihara, Katsuta, JP;
Seiya Shima, Katsuta, JP;
Takanobu Hatakeyama, Katsuta, JP;
Katsu Komuro, Mito, JP;
Assignee:
Hitachi, Ltd., Tokyo, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
B66B / ;
U.S. Cl.
CPC ...
187 / ;
Abstract
In an AC elevator system employing a three-phase induction motor for driving an elevator car, the primary voltage supplied to the induction motor is controlled to control the motoring torque in the acceleration mode and in the rated-speed running mode, while, in the deceleration mode, a power converter unit supplies AC power of low frequency to the induction motor to apply regenerative braking.