Patents by Inventor Donald G. McPherson

Donald G. McPherson has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 4751984
    Abstract: Elevator velocity profile generation is based upon combining an open loop, least time profile for acceleration with a precision closed loop, phase plane control for deceleration. The deceleration phase-plane velocity profile is generated as a modified mirror image of the acceleration profile, and transition from open loop control is within ride quality constraints. Adaptive control permits operating a drive unit closer to its limits without danger of overloading under worst case conditions, which account for a small percentage of the time. Thus, smaller drive units can be used in a given application with minimal impact on performance.
    Type: Grant
    Filed: May 3, 1985
    Date of Patent: June 21, 1988
    Assignee: Otis Elevator Company
    Inventors: Walter L. Williams, Donald G. McPherson, Arnold Mendelsohn
  • Patent number: 4674605
    Abstract: An empty elevator car is caused to lift a predetermined calibration weight(s) located above the normal car excursion. The car load sensor signals before and after lifting the calibration weight together with the known values for the empty car weight and the calibration weight are used to recalibrate the load versus signal function.
    Type: Grant
    Filed: April 18, 1986
    Date of Patent: June 23, 1987
    Assignee: Otis Elevator Company
    Inventor: Donald G. McPherson