SAWING OF LUMBER FROM LOGS OR CANT

摘要

1519986 Sawing wood ACME TIMBER INDUSTRIES Ltd 24 July 1975 [30 July 1974 20 Dec 1974] 31018/75 Heading B5L In a method of sawing an elongate workpiece, particularly a bent or curved timber workpiece, the workpiece is orientated as it is presented to the saw or saws in dependence upon the configuration of one longitudinal side thereof so as to saw the workpiece longitudinally parallel to the said configuration. The yield of useful lengths of timber from a log is thereby improved. In one embodiment, Fig. 6, sensing means comprising a roller 25 arranged in contact with the edge 9 of the log 1 to be sawn co-operate with micro-switch or other electrical means 26 to control via regulator 28 the fluid pressure applied by line 29 to a ram (not shown) which actuates an orientating roller 6, the latter acting on the edge of the log to orientate it so that the saw cuts 12 are made parallel to the edge 9. Subsequent drying of the timber eliminates undesirable curvature of the sawn boards. In another embodiment, Fig. 1, in which the curved workpiece is fed by rolls 3 to reciprocating frame saws 2, being supported by rollers 16, a single orientating roller 6 mounted on an arm 7 and urged by fluid pressure ram 8 towards a pre-set stop 11 makes contact with the concave edge 9 of the workpiece in order to position the workpiece suitable as it passes through the saws for the saw cuts 12 to be made parallel to the edge 9. In this embodiment a counter pressure roller 13 may be employed, the roller 13 making contact with the opposite edge 14 of the workpiece at substantially lower pressure than roller 6. The workpiece 1 may be positioned initially by one or other of two fluted drive rollers 4a, 4b which can be brought selectively into contact with the underside of the workpiece. Alternatively sensing means acting on the edge of the workpiece may control the use of rollers 4a, 4b to provide the necessary orientation during sawing.