Patents by Inventor John A. Campbell

John A. Campbell 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: 5452839
    Abstract: An electric stud gun positioning apparatus is attachable to a collar of a stud gun and has making parts for aligning and orienting the stud relative to a part on which the stud is to be welded.
    Type: Grant
    Filed: June 20, 1994
    Date of Patent: September 26, 1995
    Assignee: Solar Turbines Incorporated
    Inventors: John J. Kapusnik, John A. Campbell, Richard B. Griffin
  • Patent number: 4969537
    Abstract: A muffler assembly includes an inner outlet tube having a tubular portion, a frusto-conical portion and a flange portion having an expanded orifice facing the outlet of an inlet tube. Both the outlet tube and inlet tube extend within a chamber defined in an outer housing. The chamber is divided into two or more subchambers by a baffle which extends between the outlet tube and the housing. One or more holes in the baffle improve the sound attenuation characteristics of the muffler. The invention also comprehends a novel blank used in forming the outlet tube, and three alternative methods which may be used to form the outlet tube.
    Type: Grant
    Filed: November 10, 1988
    Date of Patent: November 13, 1990
    Assignee: Donaldson Company, Inc.
    Inventors: Wayne M. Wagner, John A. Campbell, William L. Burchett, John S. Wiese, John R. Hiemstra, Timothy A. Bethke
  • Patent number: 4113289
    Abstract: An improved exhaust conduit lap joint construction is disclosed, wherein the outer tube includes an end portion having therein a plurality of captured take-up slots and a plurality of relief slots which extend through the end of the tube. An inner tube extends telescopically into the outer tube end portion so as to cover the slots from the inside. Clamping means, including means encircling the outer tube and covering the captured take-up slots, hold the two tubes together, whereby a leak proof lap joint is formed.
    Type: Grant
    Filed: March 3, 1977
    Date of Patent: September 12, 1978
    Assignee: Donaldson Company, Inc.
    Inventors: Wayne M. Wagner, John A. Campbell
  • Patent number: 3997017
    Abstract: A vehicle such as a motor grader includes a hydrostatic auxiliary front wheel drive system which utilizes implement system pressurized fluid flow to drive a pair of fixed displacement hydraulic motors, such motors being drivingly connected to cause rotation of the front wheels. A pilot operated series-parallel valve in combination with a flow divider allows the motors to be driven in series or in parallel. A directional control valve is selectively responsive to operator control, and clutch actuation is accomplished automatically by directing a controlled portion of system fluid to such clutches to overcome the normal spring bias thereof.
    Type: Grant
    Filed: January 14, 1974
    Date of Patent: December 14, 1976
    Assignee: Caterpillar Tractor Co.
    Inventors: John A. Campbell, Joseph E. Dezelan, Cullen P. Hart
  • Patent number: 3953194
    Abstract: There is disclosed a process for reclaiming cemented metal carbide material by first subjecting the metal carbide material to catastrophic oxidation to produce a mixture of metal oxide and the oxide of the cement, reducing the metal oxide either mixed with the cement oxide or after being separated from it, and finally carburizing the reduced metal.
    Type: Grant
    Filed: June 20, 1975
    Date of Patent: April 27, 1976
    Assignee: Allegheny Ludlum Industries, Inc.
    Inventors: Albert G. Hartline, III, John A. Campbell, Theodore T. Magel
  • Patent number: D340638
    Type: Grant
    Filed: March 16, 1992
    Date of Patent: October 26, 1993
    Inventor: John A. Campbell