Patents by Inventor Carlton E. Graf

Carlton E. Graf 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).

  • Controlled rectifier motor drive system including d.c. fault detection and commutation means
    Patent number: 4016468
    Abstract: A motor control system of the type employing phase controlled rectifiers for controlling the power supplied from a polyphase alternating current source to a direct current motor includes circuitry to detect the existence of a rectifier which is conducting at an improper time and to provide appropriate corrective action to terminate such improper conduction.
    Type: Grant
    Filed: March 18, 1975
    Date of Patent: April 5, 1977
    Assignee: General Electric Company
    Inventor: Carlton E. Graf
  • Motor control circuit including motor current limiting means
    Patent number: 3955130
    Abstract: A motor control circuit of the type in which the effective power supplied to the motor is controlled to govern motor operation includes a fast acting current limit circuit responsive to the motor current and operative to limit the power supplied to the motor to thus prevent excessive motor current. The current limit circuit compares a signal indicative of the motor current with a reference signal having a value which varies with respect to time and which is reset in response to prescribed control circuit conditions.
    Type: Grant
    Filed: December 20, 1974
    Date of Patent: May 4, 1976
    Assignee: General Electric Company
    Inventor: Carlton E. Graf