Patents by Inventor Viljo Karkkainen

Viljo Karkkainen 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).

  • Disk defibrator
    Patent number: 4219166
    Abstract: Disk defibrator presenting a feed device for supplying the material which one desires to defibrate, such as wood chips, into the throat of the disk defibrator with the aid of a screw conveyor, the steam generated during the defibration process escaping through the feed device in countercurrent to the material flow and further passing to the atmosphere through an exit aperture on the feed device. The feed device includes two feed screws side by side with an intervening space into which the steam freely discharges.
    Type: Grant
    Filed: June 22, 1978
    Date of Patent: August 26, 1980
    Assignee: Enso-Gutzeit Osakeyhtio
    Inventors: Jorma Surakka, Martti Pokkinen, Jorma Makkonen, Erkki Valkama, Viljo Karkkainen, Pekka Rabina, Jouni Matula