Patents Examined by Gregory A. Moore
  • Patent number: 5862887
    Abstract: An elevator car door system for opening and closing elevator car doors in an elevator car includes a high performance linear induction motor having a pair of movable motor primaries, each attached to a door hanger for each door, and a stationary motor secondary attached to a header bracket which is secured to the elevator car. Each motor primary includes a primary winding and a backiron spaced apart by a plurality of spacers that establish a magnetic gap therebetween. The motor secondary fits between the primary winding and the backiron as the moving motor primaries travel across the motor secondary, generating thrust.
    Type: Grant
    Filed: November 7, 1996
    Date of Patent: January 26, 1999
    Assignee: Otis Elevator Company
    Inventors: Bruce P. Swaybill, William L. King, Thomas M. Kowalczyk, Richard E. Kulak, Michael J. Tracey, K. Narasimha Reddy, James A. Rivera