Patents by Inventor Wallace R. Birtch

Wallace R. Birtch 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).

  • Hydroformed tubular member and method of hydroforming tubular members
    Patent number: 6216509
    Abstract: Tubular members for use in vehicle frames are easily and economically produced using a hydroforming process in which a high pressure fluid is presented to the interior of a tubular member, thus causing the tube to expand to meet the interior walls of a forming die. Tubular members can be formed having significant variations in their circumference, diameter along their lengths, or gage along their lengths by using a stamped blank having a predetermined shape which is formed into a preformed tube which roughly mirrors the shape of the desired finished tubular member.
    Type: Grant
    Filed: August 25, 1998
    Date of Patent: April 17, 2001
    Assignee: R.J. Tower Corporation
    Inventors: Steven R. Lotspaih, Wallace R. Birtch