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. 10, 1990
Filed:
May. 31, 1988
David N Bogue, Tacoma, WA (US);
Charles F Horn, Puyallup, WA (US);
Steven L Washburn, Federal Way, WA (US);
Stanley L Floyd, Enumclaw, WA (US);
Weyerhaeuser Company, Tacoma, WA (US);
Abstract
The invention is a method of assisting lumber grading using an electro-optical scanning system. A first critical determination is determination of pith position of the log from which the lumber was cut, relative to the scanned faces. This then indicates knot orientation. With knot orientation known, knot size and position data also determined by the scanning system can be used to accurately estimate cross sectional area of the knots. From this point a tentative lumber grade can readily be assigned. Pith position is indicated by a number of factors including wane, knot counts on each of the faces and the presence or absences of spiky faces. A preferred form the scanner is one which measures localized wood fiber angles relative to three orthogonal axes. These fiber angle measurements reveal grain slope disturbances on the lumber which are indicative of many types of defects including knots. The system has been used for grading lumber at speeds as high as 350 m/min. with considerable accuracy.