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:
Jan. 31, 2012
Filed:
Dec. 20, 2005
Edward Piedra, Holyoke, MA (US);
Ismail Agiman, Southington, CT (US);
Daryl Marvin, Shanghai, CN;
Otis Elevator Company, Farmington, CT (US);
Abstract
An elevator drive assembly () includes a voltage regulator () that selectively introduces current under certain conditions. In one example, the voltage regulator () introduces a negative flux current to an electric motor () when the motor () is operating under conditions corresponding to constant speed movement of an elevator car (). In one example, the added negative flux current effectively reduces the back-EMF voltage of the motor () during the constant velocity portion of an elevator run. A disclosed example includes controlling the added current to maintain control over a motor torque constant, which becomes a function of the added current.