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:
Nov. 04, 1986
Filed:
Jul. 25, 1985
Matti Kahkipuro, Hyvinkaa, FI;
Heimo Makinen, Hyvinkaa, FI;
Elevator GmbH, Baar, CH;
Abstract
The present invention concerns a method for improving the dynamic converter drive for a direct current elevator motor, in which the said motor is controlled by adjusting the magnetization of the generator linked to the lifting motor, such adjustment being achieved by means of a power electronics stage controlled by the elevator speed control system, using at least elevator speed and motor current consumption (or other current information proportional thereto) as feedback parameters. The intended improvement is achieved by measuring the current values at two different points in the magnetizing circuit of the generator by means of current measuring resistors, the result of the measurement at the first point indicating the generator magnetizing current value, which is supplied to the speed control unit of the speed control system, and the current measured at the second point representing the thyristor bridge current value, which is supplied to the circuit responsible for bridge changeover control in the said power electronics stage.