Patents by Inventor Harry J. Ledgerwood

Harry J. Ledgerwood 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: 5649713
    Abstract: An elastomeric gasket comprises an annular body having an outer surface with a flanged edge, a sealing bead, and a semi-circular locking bead to facilitate insertion, and an inner surface comprising multiple, flexible angularly inwardly-extending lips that are self-sealing under pressure.
    Type: Grant
    Filed: September 14, 1995
    Date of Patent: July 22, 1997
    Assignee: Tyler Pipe Company, a div. of Ransom Industries, Inc.
    Inventor: Harry J. Ledgerwood
  • Patent number: 4580710
    Abstract: A stock feeder for repetitively feeding uniform segments of a continuous web of stock material from a roll to a production machine. The feeder comprises a frame, a pair of hold clamps located on the front portion of the frame, and a movable feed block which carries a pair of feed clamps that grips and pulls the stock material to a position which is held by the hold clamps. To obviate the necessity to reposition the clamps when changing the width of stock material, the frame includes first and second pairs of laterally adjustable stock roller guides located, respectively, on its front and rear portions.
    Type: Grant
    Filed: November 5, 1984
    Date of Patent: April 8, 1986
    Assignee: Plessey Incorporated
    Inventor: Harry J. Ledgerwood
  • Patent number: 4538839
    Abstract: A pipe joint coupling for joining cast iron hubless drain and vent pipes. The joint is encircled by an annular elastic gasket fitting over each end of the adjacent pipe sections. The elastic gasket is surrounded by a shield with a diamond pattern of projections and depressions. The shield is tightened by bands to compress the gasket against the pipes and to secure the adjacent ends of the pipes together. A tight seal is formed between the gasket and the pipe ends which is maintained under high pressure fluid passing through the pipes. The gasket is prevented from extruding from the shield by the gripping of the projections of the diamond pattern of the shield on the gasket. An improved seal between the pipes being joined is formed with increased resistant to the displacement of the gasket.
    Type: Grant
    Filed: July 6, 1984
    Date of Patent: September 3, 1985
    Assignee: Plessey Incorporated
    Inventor: Harry J. Ledgerwood
  • Patent number: 4513899
    Abstract: A stock feeder for repetitively feeding uniform segments of a continuous web of stock material from a roll to a production machine. The feeder comprises a frame, a pair of hold clamps located on the front portion of the frame, and a movable feed block which carries a pair of feed clamps that grips and pulls the stock material to a position which is held by the hold clamps. To obviate the necessity to reposition the clamps when changing the width of stock material, the frame includes first and second pairs of laterally adjustable stock roller guides located, respectively, on its front and rear portions.
    Type: Grant
    Filed: August 10, 1982
    Date of Patent: April 30, 1985
    Assignee: Plessey Incorporated
    Inventor: Harry J. Ledgerwood
  • Patent number: 4493447
    Abstract: A high speed article feeding apparatus for successively feeding articles in sheet or strip form to a work station for the performance thereon of a shaping or forming operation. A reciprocable shuttle includes a pneumatic feed clamp for clamping the work during a feed stroke and a pneumatic hold clamp for holding the work at the work station. The shuttle is operated by a pneumatic cylinder. A pneumatic circuit includes two interconnected pneumatic values to control the operation and sequencing of the elements of the feeder for fast operation without misfeeds.
    Type: Grant
    Filed: May 11, 1983
    Date of Patent: January 15, 1985
    Assignee: Plessey Incorporated
    Inventor: Harry J. Ledgerwood