Patents by Inventor Ronny Kristensson

Ronny Kristensson 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).

  • Method and apparatus for forming ribs with sideward projections in a plastic pipe, and a plastic pipe
    Patent number: 5589127
    Abstract: The invention relates to a method and an apparatus for forming ribs with sideward projections in a plastic pipe. The projections are formed by means of elongated rolls (10) each moving around the pipe and rotating about its central axis, the rolls being in an inclined position and at an oblique angle with respect to the central axis of the pipe.
    Type: Grant
    Filed: February 15, 1994
    Date of Patent: December 31, 1996
    Assignee: Uponor Innovation AB
    Inventors: Jyri Jarvenkyla, Dieter Scharwachter, .ANG.ke Johansson, Ronny Kristensson