Patents by Inventor Allen R. Obergfell

Allen R. Obergfell 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: 4606455
    Abstract: A collated fastener strip includes an elongated flexible plastic web having a row of projecting tabs along one or both of its elongated edges. Each tab is provided with an open ended slot with an opening intermediate its end in which is frictionally retained the shank of a nail or screw. The opening is of a quadrilateral configuration to provide improved frictional contact with the fastener shank. The location of the opening intermediate the ends of the slot divide the tab into two arms that can be deflected to accommodate fasteners of different sizes while retaining adequate frictional engagement therewith.
    Type: Grant
    Filed: August 17, 1984
    Date of Patent: August 19, 1986
    Assignee: Duo-Fast Corporation
    Inventors: Raimonds Grikis, Allen R. Obergfell
  • Patent number: 4294391
    Abstract: A tool for driving fasteners includes a casing defining a nose portion and a handle portion within which is a reservoir for pressurized fluid. A driver is mounted in the nose portion that is reciprocated by a piston attached thereto and an assembly for returning the piston to a static position after a driving stroke is also included. The return assembly includes a chamber in fluid communication through an inlet with pressurized air and with an outlet that is in communication with a location beneath the return piston. A diaphragm is mounted within the chamber and is biased by pressurized fluid into sealing engagement with the inlet and the outlet. Another metered inlet is also included in the chamber that is in fluid communication with the source of pressurized fluid and controls the sealing action of the diaphragm. The chamber for the return assembly is also in fluid communication with a second chamber within which is mounted a differential area piston.
    Type: Grant
    Filed: October 31, 1979
    Date of Patent: October 13, 1981
    Assignee: Duo-Fast Corporation
    Inventor: Allen R. Obergfell
  • Patent number: 4014488
    Abstract: A fastener feed assembly for a tool such as a power screwdriver having a drive member such as a rotatable bit includes a base fixed to the tool and a nose assembly slidably related to the base. The nose assembly includes a workpiece engaging surface, and when the tool is moved toward the workpiece during a fastener driving operation, the base moves toward the nose assembly. A return spring separates the base and nose assembly when the tool is withdrawn away from the workpiece. A strip of fasteners is fed from a magazine along a feed path through the nose assembly with sequential fasteners located in a drive position. Normally the drive member is spaced from a fastener in the drive position. During movement of the tool toward the workpiece in a driving operation, the drive member moves into engagement with a fastener in the drive position, and then continues to move in order to drive the fastener into the workpiece. A pawl is engageable with the strip in order to advance the strip along the feed path.
    Type: Grant
    Filed: July 10, 1975
    Date of Patent: March 29, 1977
    Assignee: Duo-Fast Corporation
    Inventors: Frank R. Potucek, Allen R. Obergfell
  • Patent number: 3930297
    Abstract: A fastener feed assembly for a tool such as a power screwdriver having a drive member such as a rotatable bit includes a base fixed to the tool and a nose assembly slidably related to the base. The nose assembly includes a workpiece engaging surface, and when the tool is moved toward the workpiece during a fastener driving operation, the base moves toward the nose assembly. A return spring separates the base and nose assembly when the tool is withdrawn away from the workpiece. A strip of fasteners is fed from a magazine along a feed path through the nose assembly with sequential fasteners located in a drive position. Normally the drive member is spaced from a fastener in the drive position. During movement of the tool toward the workpiece in a driving operation, the drive member moves into engagement with a fastener in the drive position, and then continues to move in order to drive the fastener into the workpiece. A pawl is engageable with the strip in order to advance the strip along the feed path.
    Type: Grant
    Filed: November 5, 1973
    Date of Patent: January 6, 1976
    Assignee: Duo-Fast Corporation
    Inventors: Frank R. Potucek, Allen R. Obergfell
  • Patent number: RE29527
    Abstract: A pneumatic fastener driving tool includes a safety arrangement that requires the tool to be placed against a workpiece before a manual trigger valve is operated in order to permit the tool to fire. Once the tool is placed against the workpiece the safety arrangement prevents "touch" firing by moving the tool toward and away from the workpiece. In two embodiments, the safety arrangement includes a piston valve which is fluid operated to close off a control line to the main valve of the tool whenever the trigger is operated before the tool is placed against a workpiece and when an attempt is made to "touch" fire the tool with the trigger held operated. In a third embodiment, metering orifices in a valve actuated by moving the tool against a workpiece prevent repeated "touch" operation of the tool.
    Type: Grant
    Filed: July 17, 1974
    Date of Patent: January 31, 1978
    Assignee: Duo Fast Corporation
    Inventors: Howard B. Ramspeck, Allen R. Obergfell