Patents by Inventor Per Holtstrand

Per Holtstrand 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).

  • Pipe having a socket and an apparatus for making same
    Publication number: 20050112229
    Abstract: A method and an apparatus for making a pipe, and a pipe, wherein the pipe is made from a plastic feedstock pipe by expanding it against a mould. In the first step, that portion of the plastic feedstock pipe (4) which is to have a greater diameter than the rest of the pipe is partly expanded. Only after this is the entire plastic feedstock pipe (4) expanded against the mould (1).
    Type: Application
    Filed: December 29, 2004
    Publication date: May 26, 2005
    Inventor: Per Holtstrand
  • Method of making a pipe having a socket
    Patent number: 6861026
    Abstract: A method and an apparatus for making a pipe, and a pipe, wherein the pipe is made from a plastic feedstock pipe by expanding it against a mould. In the first step, that portion of the plastic feedstock pipe (4) which is to have a greater diameter than the rest of the pipe is partly expanded. Only after this is the entire plastic feedstock pipe (4) expanded against the mould (1).
    Type: Grant
    Filed: July 22, 2002
    Date of Patent: March 1, 2005
    Assignee: Uponor Innovation AB
    Inventor: Per Holtstrand
  • Method and apparatus for making a pipe having a socket, and a pipe having a socket
    Publication number: 20030030182
    Abstract: A method and an apparatus for making a pipe, and a pipe, wherein the pipe is made from a plastic feedstock pipe by expanding it against a mould. In the first step, that portion of the plastic feedstock pipe (4) which is to have a greater diameter than the rest of the pipe is partly expanded. Only after this is the entire plastic feedstock pipe (4) expanded against the mould (1).
    Type: Application
    Filed: July 22, 2002
    Publication date: February 13, 2003
    Inventor: Per Holtstrand