Patents by Inventor Frede Hilmar Drostholm

Frede Hilmar Drostholm 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: 4082597
    Abstract: Method and apparatus for making resin tubes or pipes, the apparatus comprising a supporting structure having a cylindrical surface and a carrier strip mounted thereon and fed in a plurality of adjacent helical turns to provide a moving cylindrical surface on which the resin articles are formed. Friction reducing means is associated with the interface between the cylindrical supporting surface and the inner surface of the helical turns of the carrier strip. Provision is also made for forming articles by extruding resin material onto the moving cylindrical surface provided by the helical turns of the carrier strip.
    Type: Grant
    Filed: February 11, 1976
    Date of Patent: April 4, 1978
    Inventor: Frede Hilmar Drostholm
  • Patent number: 4081302
    Abstract: There is disclosed a method and apparatus for making tubular fiber reinforced thermosetting resin elements having a thermoplastic lining. The technique involves application of a thermoplastic lining layer to an axially moving mandrel surface, application of at least one layer of fiber reinforced thermosetting resin material superimposed upon the lining layer, providing for bonding of thermosetting and thermoplastic layers to each other, and heating the thermosetting resin to effect solidification during axial advancement of the superimposed layers with the moving mandrel surface. Provision is also made for applying a thermoplastic jacket layer superimposed upon the thermosetting layer.
    Type: Grant
    Filed: June 21, 1976
    Date of Patent: March 28, 1978
    Assignee: Frede Hilmar Drostholm
    Inventors: Frede Hilmar Drostholm, Leonard S. Meyer
  • Patent number: 4050865
    Abstract: A brick press is disclosed having a turntable carrying a plurality of molds angularly spaced from each other and having equipment associated therewith establishing a plurality of series of operating stations, each series including at least a precompression station, a compression station and an ejection station. The molds carried by the turntable are provided with replaceable liners. A material handling and feed system is also disclosed, providing for preparation of particulate or granular materials to be charged into the molds.
    Type: Grant
    Filed: September 9, 1976
    Date of Patent: September 27, 1977
    Assignee: Frede Hilmar Drostholm
    Inventors: Frede Hilmar Drostholm, Harry Jensen, Per Willadsen
  • Patent number: 4035128
    Abstract: A brick press is disclosed having a turntable carrying a plurality of molds angularly spaced from each other and having equipment associated therewith establishing a plurality of series of operating stations, each series including at least a precompression station, a compression station and an ejection station. A material handling and feed system is also disclosed, providing for preparation of particulate or granular materials to be charged into the molds.
    Type: Grant
    Filed: September 30, 1974
    Date of Patent: July 12, 1977
    Assignee: Frede Hilmar Drostholm
    Inventors: Frede Hilmar Drostholm, Harry Jensen, Per Willadsen
  • Patent number: 4022669
    Abstract: Equipment is provided having a distillation tank with a heater and a vapor offtake, with a condenser receiving the offtake vapor and delivering liquid condensate. A control system provides safety features including pressure and temperature responsive devices operative to shut off the heater and further including means for shut off of the heater when the tank is being filled. Still further provision is made for shutting off the heater under the influence of a float valve associated with the condensate discharge line and operative to shut off the heater under the influence of rise in level of condensate in the receiving vessel.
    Type: Grant
    Filed: June 24, 1975
    Date of Patent: May 10, 1977
    Assignee: Frede Hilmar Drostholm
    Inventors: Frede Hilmar Drostholm, Kaj Ditlev Frederik Petersen, Ulf Raabo
  • Patent number: 4011354
    Abstract: There is disclosed a method and apparatus for making tubular fiber reinforced thermosetting resin elements having a thermoplastic lining. The technique involves application of a thermoplastic lining layer to an axially moving mandrel surface, application of at least one layer of fiber reinforced thermosetting resin material superimposed upon the lining layer, providing for bonding of thermosetting and thermoplastic layers to each other, and heating the thermosetting resin to effect solidification during axial advancement of the superimposed layers with the moving mandrel surface. Provision is also made for applying a thermoplastic jacket layer superimposed upon the thermosetting layer.
    Type: Grant
    Filed: March 22, 1972
    Date of Patent: March 8, 1977
    Assignee: Frede Hilmar Drostholm
    Inventors: Frede Hilmar Drostholm, Leonard S. Meyer
  • Patent number: 3979250
    Abstract: Method and apparatus for making resin tubes or pipes, the apparatus comprising a supporting structure having a cylindrical surface and a carrier strip mounted thereon and fed in a plurality of adjacent helical turns to provide a moving cylindrical surface on which the resin articles are formed. Friction reducing means is associated with the interface between the cylindrical supporting surface and the inner surface of the helical turns of the carrier strip. Provision is also made for forming articles by extruding resin material onto the moving cylindrical surface provided by the helical turns of the carrier strip.
    Type: Grant
    Filed: August 16, 1971
    Date of Patent: September 7, 1976
    Inventor: Frede Hilmar Drostholm
  • Patent number: 3943224
    Abstract: Method and apparatus for making resin tubes or pipes, the apparatus comprising a supporting structure having a cylindrical surface and a carrier strip mounted thereon and fed in a plurality of adjacent helical turns to provide a moving cylindrical surface on which the resin articles are formed. Friction reducing means is associated with the interface between the cylindrical supporting surface and the inner surface of the helical turns of the carrier strip. Provision is also made for forming articles by extruding resin material onto the moving cylindrical surface provided by the helical turns of the carrier strip.
    Type: Grant
    Filed: November 24, 1972
    Date of Patent: March 9, 1976
    Inventor: Frede Hilmar Drostholm