Patents by Inventor Anders Andtbacka

Anders Andtbacka 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).

  • Preparation of an end of a thermoplastics tube manufactured by spirally winding a hollow profile
    Patent number: 6666945
    Abstract: A method for preparing an end of a thermoplastics tube (1) is provided, wherein the tube is manufactured by spirally winding and welding together of a hollow profile (1a) having a substantially rectangular cross section. The method includes the following steps: cutting the end of the tube by a planar transversal section; extruding a second hollow profile (2) having a rectangular cross section and an outer shape essentially similar to Fat of the hollow profile (1a) from which the tube (1) is manufactured; spirally winding the extruded second hollow profile (2) around a drum having a diameter corresponding to inner diameter of the tube (1); cutting a loop (2a) from the second hollow profile (2) in a length corresponding to circumference of the tube end; joining the ends of the loop (2a) to each other, whereby a ring (2b) is formed having the same inner and outer diameters as the spirally wound tube (1); placing the ring (2b) against the cut tube end; and welding the ring (2b) to the tube end.
    Type: Grant
    Filed: October 9, 2001
    Date of Patent: December 23, 2003
    Assignee: Oy KWH Pipe Ab
    Inventors: Anders Andtbacka, Gunnar Blomqvist, Stefan Slotte
  • Method for joining spiral wound pipes
    Patent number: 6322653
    Abstract: A method for joining thermoplastic pipes made by spiral winding a hollow profile with mainly rectangular cross section.
    Type: Grant
    Filed: June 30, 1999
    Date of Patent: November 27, 2001
    Assignee: Oy Kwh Pipe Ab
    Inventors: Gunnar Blomqvist, Stefan Slotte, Anders Andtbacka