Patents by Inventor E. James Perkins

E. James Perkins 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).

  • Hydraulic lock for resistance welders
    Patent number: 4812612
    Abstract: A hydraulic system for use in a resistance welding machine with a stationary electrode and a variable electrode to provide adjustment of the stationary electrode to ensure proper positioning to maintain weld quality. The hydraulic system comprising an actuated piston attached to the stationary electrode, a motive piston to control the flow of hydraulic fluid in the hydraulic system, a hydraulic locking device to lock the stationary electrode in a stationary position to resist forces during the welding operation and a pneumatic control system to operate the hydraulic system.
    Type: Grant
    Filed: January 11, 1988
    Date of Patent: March 14, 1989
    Assignee: Chrysler Motors Corporation
    Inventor: E. James Perkins