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:
Sep. 29, 1998
Filed:
Mar. 29, 1996
Timothy M Remmers, Winsted, CT (US);
Randall K Roberts, Amston, CT (US);
Rajesh Rajamani, East Hartford, CT (US);
Roy S Colby, Tariffville, CT (US);
Otis Elevator Company, Farmington, CT (US);
Abstract
The invention provides an elevator system for controlling movement of an elevator car with respect to guide rails in an elevator hoistway, having a force-estimation or position-scheduled current command controller and a magnet driver circuit without the need for a flux sensor. The force-estimation or position-scheduled current command controller responds to a force command signal, and further responds to a sensed gap signal, for providing a force-estimation or position-scheduled current command controller signal as a current command to the magnet driver circuit. The magnet driver circuit responds to the force-estimation or position-scheduled current command controller signal, for providing a magnet driver circuit signal to control said horizontal movement of the elevator car with respect to the guide rail in the elevator hoistway, whereby the horizontal movement of the elevator car is controlled without sensing magnetic flux. Other applications include any system that uses an electromagnet to produce an attractive or repulsive force across a large air gap, such as magnetic levitation trains or shuttles, and magnetic bearings.