Patents by Inventor Axel M. Heden, deceased

Axel M. Heden, deceased 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).

  • Grille for loudspeaker cabinet
    Patent number: 4227590
    Abstract: For use with a cabinet containing at least one loudspeaker, a grille is provided which is comprised of elongated frame members connected by corner brackets. A rigid superstructure, comprising corner ridge members and one or more central ridge members joined by ridge joint members, is attached to the frame at the corner brackets, and a covering material is disposed over the superstructure and frame. Any size grille can be constructed using the same corner brackets and ridge joint members.
    Type: Grant
    Filed: March 7, 1978
    Date of Patent: October 14, 1980
    Assignee: Superscope, Inc.
    Inventors: John R. Ballantyne, Axel M. Heden, deceased