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. 28, 1989
Filed:
May. 18, 1988
Applicant:
Inventor:
Hiroyuki Ikejima, Inazawa, JP;
Assignee:
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
B66B / ;
U.S. Cl.
CPC ...
187119 ; 318807 ;
Abstract
An apparatus for controlling an A.C. powered elevator is provided to reduce a primary current frequency to an induction motor to be smaller than a specific value when the motor is switched from a power drive to a brake mode of operation. In other words, the frequency after the motor is switched to the brake mode is reduced to be lower than the frequency at which the machine input power to the induction motor is equal to the internal power consumption of the induction motor.