Patents by Inventor Kimmo Ritvanen

Kimmo Ritvanen 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).

  • Fire closure shutter
    Patent number: 5425673
    Abstract: A fire shutter comprises a plurality of substantially planar fire plate elements each having first and second opposite edges and supported so that they are adjacent to each other and turnable about respective parallel axes from a flow-through open position, in which gas-flow passages are formed between the plate elements, to a closed position, in which the first edge of one plate element of each pair of adjacent plate elements is close to the second edge of the other plate element of the pair and the fire plate elements together form a closed barrier.
    Type: Grant
    Filed: August 11, 1993
    Date of Patent: June 20, 1995
    Assignee: Kvaerner Masa-Yards OY
    Inventors: Timo Mahlanen, Kimmo Ritvanen, Arvo Rasanen, Outi Siivonen