Patents by Inventor Leif Ringstrom

Leif Ringstrom 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).

  • Method and apparatus for detecting bark and for determining the degree of barking on wood and chips
    Patent number: 5274244
    Abstract: The present invention relates to a method and to an apparatus for detecting the presence of bark and for determining the barking degree of wood or chips. Accordingly, the apparatus includes a light source (12) which directs a concentrated light beam (14) onto the measurement object (16), for instance a log which is moved continuously in a transport chute (20). The shape and/or size of the light image obtained on the log (16) at the point (18) on which the light beam (14) impinges on the log is detected with the aid of a camera (10), preferably a CCD-camera. The shape and/or size of the light image is mutually different for wood and bark. The detection values obtained by the CCD-camera (10) are evaluated in a processing means.
    Type: Grant
    Filed: May 18, 1992
    Date of Patent: December 28, 1993
    Assignee: STFI
    Inventors: Lennart Johansson, Leif Ringstrom