Patents by Inventor Robert E. Wintringham

Robert E. Wintringham 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).

  • Magnetic captive key switch lock
    Patent number: 3941954
    Abstract: A cylinder and plug type lock mechanism drivingly connects an authorized key to the actuator of a switch device and captivates the key when turning the switch on. A magnetic latch activated in the captive position of the key, prevents return of the key to its release position. A magnetic release element is positioned on the key against the lock mechanism to disengage the magnetic latch.
    Type: Grant
    Filed: September 10, 1974
    Date of Patent: March 2, 1976
    Inventor: Robert E. Wintringham