Patents by Inventor Lawrence L. Grover

Lawrence L. Grover 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).

  • Motor speed control circuit
    Patent number: 4011491
    Abstract: A speed-controlling circuit for controlling the rotational speed of a D.C. electric motor in which the electric current is supplied to the D.C. motor through a switching circuit which is periodically open for a predetermined fixed time interval. The switching circuit is controlled by electrical pulses having a repetition rate which varies in dependence upon the rotational speed of the motor, whereby to periodically interrupt the supply of current to the motor.
    Type: Grant
    Filed: March 21, 1975
    Date of Patent: March 8, 1977
    Assignee: Heath Company
    Inventors: Lawrence L. Grover, David L. Plangger