Patents by Inventor James P. Krul

James P. Krul 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).

  • Control system for electromagnetic lock
    Patent number: 6611414
    Abstract: An electromagnetic door lock has an electromagnet and an armature for bonding thereto. One of the electromagnet and the armature is adapted for mounting to a door and the other of the electromagnet and the armature is adapted for mounting to a door frame. A lock controller pulses current to the electromagnet. The pulses have a predetermined width and a predetermined spacing between pulses.
    Type: Grant
    Filed: August 30, 1996
    Date of Patent: August 26, 2003
    Assignee: Harrow Products, Inc.
    Inventors: Gary E. Lavelle, James P. Krul