Patents by Inventor Frederick T. Richards

Frederick T. Richards 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).

  • Permanent magnet motor control system
    Patent number: 4288726
    Abstract: A plurality of permanent magnet DC motors are grouped into two banks. One side of each motor in one bank is connected to a first common supply conductor while one side of each motor in the other bank is connected to a second common supply conductor. Independently operable switches are provided for connecting the other sides of respective ones of the motors in the first and second banks to a third common supply conductor. Three additional power switches are provided for reversibly connecting a source of potential across either bank of motors. By proper switch selection one or more motors in either of the banks may be operated in a selected direction of rotation.
    Type: Grant
    Filed: March 31, 1980
    Date of Patent: September 8, 1981
    Assignee: General Motors Corporation
    Inventors: Alfonso Vazquez-Cuervo, Frederick T. Richards, Daniel V. Bafunno, George Papacostas