Patents by Inventor Robert G. Steffen

Robert G. Steffen 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: 4309140
    Abstract: A threaded bolt has two elongated shank parts, the adjoining part ends having mating, stepped shapes. The shank parts when held and rotated in unison can be threaded in a piece such as a nut, but when not so held will frictionally bind in the threads of the piece. A keyway is provided through the shank parts to receive a key for rotating the parts in unison, preventing relative rotational movement therebetween, so that the nut and shank parts may be freely threadingly rotated in the aforesaid piece.
    Type: Grant
    Filed: October 3, 1979
    Date of Patent: January 5, 1982
    Assignee: LeVone A. Blough
    Inventors: Robert G. Steffen, David L. Gregory, LeVone A. Blough
  • Patent number: 4261093
    Abstract: A tool and method for cutting the housing of a lock assembly for gaining legitimate entry into a locked enclosure, the housing including an annular flange portion and receiving a lock mechanism having a lock trunnion. The trunnion is provided with a key-receiving slot and the lock mechanism is otherwise conventional.The tool includes a blade for cutting the flange off said housing. An elongated pilot key element is provided with a journal mounted for rotation relative to said blade about the axis of rotation of the latter. The key element is disposed radially within the rotational path of the blade and is adapted to be received by the slot within the trunnion to serve as a locator for the blade. By reason of the journal connection between the key element and the blade, the key element serves as a rotational guide for the blade which causes the latter to follow a given circular path in cutting the aforesaid flange from the housing when the key element is inserted in the trunnion slot.
    Type: Grant
    Filed: February 26, 1979
    Date of Patent: April 14, 1981
    Assignee: David L. Gregory
    Inventors: Robert G. Steffen, David L. Gregory