With Specific Electrical Control Therefor Patents (Class 187/316)
  • Patent number: 5378861
    Abstract: In response to requested flight time, creep in distance, creep out distance and creep speed, a profile for opening or closing an elevator door is provided. The distance over which acceleration and deceleration must occur is the doorway distance less the distance which would be covered at the creep speed. Maximum speed is the acceleration distance over the acceleration time (1/4 of the requested flight time, to allow for jerk to both increase and decrease both acceleration and deceleration). Acceleration is the maximum speed over the acceleration time, and jerk is acceleration over the acceleration time. Actual flight time is calculated, taking into account maximum acceleration and velocity, and periods of constant acceleration and velocity, if any.
    Type: Grant
    Filed: February 16, 1993
    Date of Patent: January 3, 1995
    Assignee: Otis Elevator Company
    Inventors: Michael Barten, Mustapha Toutaoui
  • Patent number: 5373120
    Abstract: A linear motor is used to actuate an elevator door in response to a control signal for counteracting rotational torque caused by a variable-length moment arm about the center of gravity of the door by varying the magnitude of a linear force exerted on the door acting through a fixed-length moment arm about the center of gravity of the door for providing an opposing rotational torque, thereby counteracting the rotational torque caused by the normal force. The first and second rotational torques may be controlled to decrease and increase linearly as the door goes through its motion. In this way, the velocity profile varies in a curve similar to one side of the major axis of an ellipse. The normal force may be provided so as to levitate the door to reduce gravitational forces acting on door rollers. The control may be carried out in an open- or closed-loop fashion.
    Type: Grant
    Filed: March 10, 1993
    Date of Patent: December 13, 1994
    Assignee: Otis Elevator Company
    Inventors: David W. Barrett, Richard E. Peruggi, Louis Bialy, Ernest P. Gagnon