Patents by Inventor James C. Hamrick

James C. Hamrick 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: 7621505
    Abstract: A carrier for pulling line through conduit, the carrier or line runner being an inflatable plastic sleeve that is closed at one end with gusset openings at the other end through which a line may pass and be tied to itself so that when the line runner is placed in a conduit with its closed end in the direction of travel, the application of lower pressure at the closed end will cause the sleeve to inflate and be propelled in the direction of the lower pressure pulling the line with it.
    Type: Grant
    Filed: February 28, 2007
    Date of Patent: November 24, 2009
    Inventor: James C. Hamrick
  • Publication number: 20090056079
    Abstract: A rope pull bar for pulling rope through conduit, said pull bar having a V-shaped notch or slot on an edge in the center of the bar with a perpendicular post on the bar extending outwardly adjacent the bottom of the V so that a rope may be looped around the post and the rope section from the upper run of the loop is positioned in the V-slot whereby when pulled in the direction opposite the point of the V, the upper run of rope will clamp the loose end of the lower run against the bar and provide a secure hold on the rope for further pulling.
    Type: Application
    Filed: September 5, 2007
    Publication date: March 5, 2009
    Inventor: James C. Hamrick
  • Publication number: 20080203368
    Abstract: A carrier for pulling line through conduit, the carrier or line runner being an inflatable plastic sleeve that is closed at one end with gusset openings at the other end through which a line may pass and be tied to itself so that when the line runner is placed in a conduit with its closed end in the direction of travel, the application of lower pressure at the closed end will cause the sleeve to inflate and be propelled in the direction of the lower pressure pulling the line with it.
    Type: Application
    Filed: February 28, 2007
    Publication date: August 28, 2008
    Inventor: James C. Hamrick
  • Patent number: 5259418
    Abstract: A heat reshapeable rigid conduit and method for forming an elbow or offset having any desired bend radius therefrom. The rigid conduit is formed of a flexible metal tubing with a layer of heat softenable plastic preferably covering the exterior surface thereof. The conduit may be heated using conventional electric heaters on the job site, then shaped into the desired bend radius to form an elbow or offset. The plastic layer provides rigidity to the elbow or offset upon cooling. The flexible metal tubing has interlocking overlapping joined edges that permit flexing of the tubing when the plastic layer is heat softened. The flexible metal tubing resists the sawing action of a pulling line during the installation of an electrical conductor in the conduit. The plastic outer layer permits quick and inexpensive coupling between adjacent conduit sections.
    Type: Grant
    Filed: March 18, 1991
    Date of Patent: November 9, 1993
    Inventor: James C. Hamrick
  • Patent number: 4596381
    Abstract: Pull lines are utilized for installing electric wires in electrical conduit between junction boxes by attaching a pull line to the near end of a hollow-core line carrier having its forward end closed by a collapsible bag-like member of highly flexible plastic film or fabric. The bag-like member has a cross-section greater than that of the conduit and is inflatable through the trailing end of the line carrier so to maintain a yieldable continuous contact with the conduit interior wall about the line carrier as the carrier is moved through the conduit in response to a pressure differential created at one end of the conduit. In one form, the line carrier is a tubular sleeve of rigid or shape retaining material to which the pull line to be installed is attached; and, in a second form, it is a roll of the line itself which is disposed within the open end of the bag-like member. In a modification of the first form, the bag-like member is collapsed for storage within the sleeve.
    Type: Grant
    Filed: May 19, 1980
    Date of Patent: June 24, 1986
    Assignee: Thomas Industries, Inc.
    Inventor: James C. Hamrick
  • Patent number: 4202531
    Abstract: Utility lines or cables are installed in underground conduit using imperforate flexible tubing having a circumference no less than that of the conduit interior. One end of the tubing is everted and fixed within the conduit near end. Air blown into said near end is directed against a displaceable pocket between the fixed everted end and entering portion of the tubing so that the tubing lines the conduit interior wall, taking its shape and strength therefrom, as it is advanced through the conduit to the far end thereof. In one embodiment, the tubing when half way through is severed outside the conduit near end and a pull line attached thereto is drawn with the tubing the rest of the way through the conduit to its far end; and the tubing is twisted on the pull line to form a tow of higher tensile strength.
    Type: Grant
    Filed: October 2, 1978
    Date of Patent: May 13, 1980
    Assignee: Thomas Industries of Tennessee Inc.
    Inventor: James C. Hamrick