Log conditioning before mechanical debarking

摘要

High powered lasers are used to score the bark on logs before they are mechanically debarked. Typical of the lasers employed are multi-kilowatt CO2 industrial lasers. A high powered laser beam is brought to a focus just above the surface of the bark on the log. A jet of compressed air is blown coaxially with the beam and facilitates the beam's formation of a narrow slot in the surface of the bark. Logs are advanced and rotated by a plurality of parallel augers extending across the base of a trough. The lasers are positioned in a gap beneath and in between sets of augers. The beam's focus may be adjustable with respect to the bark's surface. The motion of the log with respect to a laser head produces a spiral cut along the surface of the log which slices the long fibers in the bark,