Patents by Inventor Clifton E. Groombridge

Clifton E. Groombridge 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).

  • Apparatus and method for controlling the rotary airlocks in a coal processing system by reversing the motor current rotating the air lock
    Patent number: 5575085
    Abstract: An improvement to a coal processing system where hard materials found in the coal may cause jamming of either inflow or outflow rotary airlocks, each driven by a reversible motor. The instantaneous current used by the motor is continually monitored and compared to a predetermined value. If an overcurrent condition occurs, indicating a jamming of the airlock, a controller means starts a "soft" reverse rotation of the motor thereby clearing the jamming. Three patterns of the motor reversal are provided.
    Type: Grant
    Filed: July 17, 1995
    Date of Patent: November 19, 1996
    Assignee: Western Syncoal Company
    Inventor: Clifton E. Groombridge