Patents by Inventor David McKenzie Hill

David McKenzie Hill 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: 6582634
    Abstract: A method of converting a plastics material into a yarn, in which the plastics material includes one or more polymers selected from the group consisting of nylon, polyesters, polyethylene, polyvinyl chloride, polyphenylene sulphide, polystyrene. The method includes heating the material to melt it, pumping the melted material through an extruder to form an extruded filament, and cooling the extruded filament. The cooled filament is passed through a first draw roller assembly while elevating the temperature of the filament. The filament is then heated in a heating zone as it exits the first draw roller assembly and, thereafter, the filament is passed through a second draw roller assembly operating at a different linear speed to the first draw roller assembly. The filament is spooled after exiting the second draw roller assembly.
    Type: Grant
    Filed: May 22, 2001
    Date of Patent: June 24, 2003
    Assignee: Peri-Dent Limited
    Inventors: Ian Roberts, David McKenzie Hill
  • Publication number: 20010041262
    Abstract: A method of converting a plastics material into a yarn in which the plastics material comprises one or more polymers selected from the group consisting of nylon, polyesters, polyethylene, polyvinyl chloride, polyphenylene sulphide, polystyrene. The method comprises heating the material to melt it, pumping the melted material through an extruder to form an extruded filament, and cooling the extruded filament. The cooled filament is passed through a first draw roller assembly while elevating the temperature of the filament. The filament is then heated in a heating zone as it exits the first draw roller assembly and, thereafter, the filament is passed through a second draw roller assembly operating at a different linear speed to the first draw roller assembly. The filament is spooled after exiting the second draw roller assembly.
    Type: Application
    Filed: May 22, 2001
    Publication date: November 15, 2001
    Inventors: Ian Roberts, David McKenzie Hill