Patents by Inventor Stuart D. Loudon

Stuart D. Loudon 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).

  • Induction motor start-stall detection apparatus and method
    Patent number: 4547720
    Abstract: A stall detection method for electric induction motors and apparatus utilized the stator current and voltage phase difference as proportional to percentage synchronous motor speed, and detects a stall condition from this speed as a parameter of motor movement. The invention includes differentiating the phase difference to obtain motor acceleration as a parameter potentially indicative on its own, or in conjunction with phase difference, of a motor stall condition.
    Type: Grant
    Filed: October 11, 1983
    Date of Patent: October 15, 1985
    Assignee: Newelec Pretoria Ltd.
    Inventor: Stuart D. Loudon