Patents by Inventor Eilif Risberg

Eilif Risberg 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).

  • Electrical resistance heating element
    Patent number: 4501956
    Abstract: Electrical resistance heating element including a number of metal strips arranged in a meander-like pattern. In the resistance metal strips, which are made from a non-expensive base sheet material like lead, there is incorporated at least one fuse which will operate if the heat transfer from a randomly placed area of critical size (a critical area) is substantially blocked. The fuse or fuses are preferably constituted by a lead/tin alloy rolled into intimate contact with the lead base material.
    Type: Grant
    Filed: September 18, 1981
    Date of Patent: February 26, 1985
    Assignee: International Standard Electric Corporation
    Inventors: Hans A. Bergersen, Eilif Risberg