Patents by Inventor Ulf Bergstrom

Ulf Bergstrom 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).

  • Building element having spaced longitudinal members with each member having a different moisture content
    Patent number: 4617776
    Abstract: The present invention concerns a prefabricated composite and relatively strong, but light-weight building element which in a simple embodiment consists of two substantially parallel elements (1, 2) spaced apart a given distance and interconnected by intermediate spacer and interconnecting means (3). The invention is characterized in that said prefabricated building element, in order to compensate for expected climatic differences at opposite sides of a building structure, or to compensate for expected loads in the position of use of said prefabricated building element, during or immediately after assembly and interconnection of the parts of said building element has at one of the long sides of said building element a camber (curvature) produced by the different moisture ratios of the two longitudinal elements.
    Type: Grant
    Filed: December 17, 1982
    Date of Patent: October 21, 1986
    Assignee: Armerad Betong Vagforbattringar AB
    Inventor: Ulf Bergstrom