The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Apr. 30, 1985
Filed:
Jan. 28, 1983
Sakari Heikkila, Espoo, FI;
Martti Tiuri, Espoo, FI;
A.Ahlstrom Osakeyhtio, Noormarkku, FI;
Abstract
A method and an apparatus for detection of flaws in lumber is provided, in which the lumber is subjected to microwave radiation of equal intensity in turns simultaneously from two microwave radiation means in phase opposition and from an intermediate microwave radiation means and between the turns from none of said microwave radiation means. The microwave radiation transmitted through the lumber is measured and the level of the measured signals in pulse form is adjusted in such a way that the mean value of the pulse train equals a reference value. The level of the pulse train when no radiation is transmitted is adjusted to zero and the level of the pulses when said two microwave radiation means in phase opposition radiate is used as a measure of the size of the flaw in the lumber.