Patents by Inventor Derek Firth

Derek Firth 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: 6059199
    Abstract: A road transportable concrete railroad long-line tie molding system is described in which a rigid horizontal metal stressing frame is assembled from transportable sub-frame segments. The sub-frame segments are releasably connected in axially aligned end-to-end relation, and include parallel longitudinal reaction members. In a preferred form, the sub-frame segments are convertible from inoperative transport conditions to extended operative conditions. Footings are provided along the stressing frame length to engage the sub-frame segments to releasably mount the sub-frame segments in axial alignment and stabilize the reaction members against lateral deflection during compressive loading. A plurality of conventional gang tie molds having upwardly open elongated mold cavities are releasably received in end-to-end alignment along the framework. A reinforcing wire anchor is provided on the sub-frame at the dead end of the framework and a tensioner is located at the live end of the framework.
    Type: Grant
    Filed: January 30, 1998
    Date of Patent: May 9, 2000
    Assignee: CXT, Incorporated
    Inventors: Anders L. U. Eriksson, Derek Firth, Rick W. Petersen, John G. White
  • Patent number: 5766648
    Abstract: A road transportable concrete railroad long-line tie molding system is described in which a rigid horizontal metal stressing frame is assembled from transportable sub-frame segments. The sub-frame segments are releasably connected in axially aligned end-to-end relation, and include parallel longitudinal reaction members. In a preferred form, the sub-frame segments are convertible from inoperative transport conditions to extended operative conditions. Footings are provided along the stressing frame length to engage the sub-frame segments to releasably mount the sub-frame segments in axial alignment and stabilize the reaction members against lateral deflection during compressive loading. A plurality of conventional gang tie molds having upwardly open elongated mold cavities are releasably received in end-to-end alignment along the framework. A reinforcing wire anchor is provided on the sub-frame at the dead end of the framework and a tensioner is located at the live end of the framework.
    Type: Grant
    Filed: October 21, 1996
    Date of Patent: June 16, 1998
    Assignee: CXT Incorporated
    Inventors: Anders L. U. Eriksson, Derek Firth, Rick W. Petersen, John G. White
  • Patent number: 5018300
    Abstract: Disclosed is a hanging basket liner for lining wire and other types of hanging baskets designed to hold live, growing plants and flowers or artificial plants or flowers. The liner is of a construction which incorporates a covering of sphagnum moss on its outer surface, so that it has a natural appearance. The flexible material from which the inner liner is made is adaptable, by cutting and trimming, to fit various sizes and shapes of hanging baskets. The liner, which has a diameter in the range from 17 inches to 48 inches and a thickness in the range from 1/4 to 1/2 inch, has a inner lining with sponge like properties which retains moisture, reduces the drying out of the growing medium and is durable, long lasting and reuseable. The liner has a number of vanes emanating from its center so that side slits, through which trailing plants can grow, are created as the liner conforms to the shape of the hanging basket.
    Type: Grant
    Filed: October 23, 1989
    Date of Patent: May 28, 1991
    Inventors: Martin T. Chiu, Derek A. Firth