Patents by Inventor Paul R. Crawford

Paul R. Crawford 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: 7568444
    Abstract: A folding kayak includes fore and aft subassemblies which are joined together and are covered by a water-impermeable skin to provide a watercraft with the favorable attributes both hard shell and skin on frame kayaks, with none of the disadvantages. In addition, one or more hydraulic adjustment mechanisms provide the kayak with characteristics of a plurality of different rigid body kayaks, with different operational characteristics, suitable for open-ocean or closed-water environments as desired. Ribs which are part of the kayak assembly have a relatively flat profile, making the kayak perform more favorably in adverse water conditions, and also giving the kayak some resilience and flexibility when encountering obstructions in the water. In one aspect, the kayak subassemblies may be joined, at least in part, by corrugated splines. By rotating these corrugated splines within elongate tubes that form part of the respective subassemblies, it is possible to remove crystalline, corrosive, and other build-up.
    Type: Grant
    Filed: August 6, 2007
    Date of Patent: August 4, 2009
    Assignee: Trak Kayaks (Barbados) Ltd.
    Inventors: Gordon E. Espeseth, Gord B. Heisler, Bryon J. Heisler, Paul R. Crawford
  • Patent number: 5720670
    Abstract: A golf practice platform is provided having a practice surface which can be tilted to simulate up hill, down hill and side hill shots by the action of a pair of screw drives and a pair of double acting hydraulic cylinders acting about a universal joint. A golf practice mat is also provided for use on the tilting platform or on other golf practise surfaces. The mat provides a means for varying the exposed height of the bristles to simulate grass conditions such as tee box, fairway and rough.
    Type: Grant
    Filed: July 26, 1996
    Date of Patent: February 24, 1998
    Assignee: Griffin Intellectual Property Development Corporation
    Inventors: Bruce J. Oxley, Gary A. Stegmeier, Paul R. Crawford
  • Patent number: 4280553
    Abstract: There is disclosed a process for storing energy by use of the heat of fusion of hydrated salts which are within a bulk container having heat exchange means. The process prevents stratification and supercooling from occurring during the heat releasing cycles by internally circulating the molten salt within the container and also by preventing the temperature of the salt from rising above that at which complete melting of the salt crystals within the container occurs.
    Type: Grant
    Filed: March 16, 1979
    Date of Patent: July 28, 1981
    Assignee: Allied Chemical Corporation
    Inventors: Samuel L. Bean, James W. Swaine, Jr., Paul R. Crawford