Patents by Inventor Martin Graham Wiseman

Martin Graham Wiseman 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).

  • Stall detection in stepper motors
    Patent number: 6667595
    Abstract: A stall detection method and system for a stepper motor ascertains a stalled condition according to current rise time of the windings. The motor is determined to be in a normal running condition when current rise time of opposed windings is substantially constant, including monotonic increases and monotonic decreases, in cycles of the rotor. The motor is determined to be in a stalled condition when the current rise time of opposed windings has a relative short-long pattern.
    Type: Grant
    Filed: February 19, 2002
    Date of Patent: December 23, 2003
    Assignee: Dresser, Inc.
    Inventor: Martin Graham Wiseman
  • Stall detection in stepper motors
    Publication number: 20030155883
    Abstract: A stall detection method and system for a stepper motor ascertains a stalled condition according to current rise time of the windings. The motor is determined to be in a normal running condition when current rise time of opposed windings is substantially constant, including monotonic increases and monotonic decreases, in cycles of the rotor. The motor is determined to be in a stalled condition when the current rise time of opposed windings has a relative short-long pattern.
    Type: Application
    Filed: February 19, 2002
    Publication date: August 21, 2003
    Applicant: Dresser, Inc.
    Inventor: Martin Graham Wiseman