Patents by Inventor David W. Schlicher

David W. Schlicher 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: 4065703
    Abstract: A starting control system for synchronous motors having circuits for detecting motor speed, the zero crossings of the current induced in the field windings, and the motor load angle. A circuit responsive to the detected motor speed, zero crossings and load angle triggers the DC excitation of the field at the zero crossings upon reaching a predetermined rotor speed and terminates the DC excitation at predetermined load angles. The pulsed DC excitation provides a torque that pulls the rotor into synchronism within several rotor slip cycles. In one embodiment the pulsed DC excitation is applied on both positive and negative half-cycles of the induced field current waveform.
    Type: Grant
    Filed: November 22, 1976
    Date of Patent: December 27, 1977
    Assignee: Electric Machinery Mfg. Company
    Inventors: David W. Schlicher, Liboslav Fabian