Patents by Inventor John L. Harkins

John L. Harkins 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: 5389753
    Abstract: A feed control switch is provided for controlling the supply of feed to a hopper without the need to contact the feed. The control switch includes first member having a switch contact surface and a second member slidably moveable relative to the first member, the second member having a suspender from which the hopper is suspended. A spring biasing arrangement pulls the first and second members together at a predetermined spring bias strength and switch, adjacent to the switch contact surface and at the second member, is provided which is in the off position when the switch is at an extended position and is in the on position when depressed by the contact surface. When the weight of feed in the hopper exceeds the predetermined spring bias strength, the second member pulls away from the first member causing the switch to move away from and disengage the switch contact surface so that the switch moves to the extended and off position thereby signally the cut off of feed to the hopper.
    Type: Grant
    Filed: August 3, 1993
    Date of Patent: February 14, 1995
    Inventor: John L. Harkins