Patents by Inventor Birte Christensen

Birte Christensen 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).

  • Mandrel for winding spherical containers
    Patent number: 3951349
    Abstract: A mandrel for use in the production of containers wherein a filament or strip shaped material is wound on to the mandrel, the mandrel consisting of a bladder core wholly or partially enclosed within a flexible jacket and having stiffening members inserted between the bladder core and the jacket. Said members are detachably or pivotally connected to a coupling member for mounting the mandrel on a shaft.
    Type: Grant
    Filed: January 3, 1973
    Date of Patent: April 20, 1976
    Inventors: Birte Christensen, Borge Christensen, Helge Hovad, Karl Erik Hovad