GB946985A - Improved cutter unit for wood chippers - Google Patents

Abstract

946,985. Woodworking cutters. ALWOOD A.G. Dec. 15, 1961 [Dec. 16, 1960], No. 45122/61. A rotary or reciprocable wood chipping cutter has multi-edge blades 6, Fig. 1, releasably clamped along a groove 3 in a holder 1 so that they can be removed when an edge becomes dull or damaged and replaced with another edge in cutting position. The blades 6 may have the form of truncated pyramids as shown in Figs. 1 and 2 or may be of spool form 18 as shown in Fig. 7 and comprise two blades 6 welded together at the truncated portion or be formed as an integral unit. The blades may be made wholly of nitrided steel or hard alloy or may have hard tips. In Fig. 1, a clamping bar 11 secured by bolts 16 bears on a rib 10 and has surfaces 12, 13 pressing the blades against the face 5 of the groove 3 and into the V-shaped bottom of the groove. Spacing blocks 17, Fig. 2, are provided between the blades. In Fig. 7, clamps 21 of U-shape embrace the spool-type blades 18 and have hooks 22 engaging a shaft 23 extending across the holder. Spaced cams on the shaft engages the walls of a bore 24 and by rotating the shaft by means of worm gearing the clamps draw the blades against surfaces 20, 20a. In Fig. 14, the blades 41 are each pulled down against the inclined surface 40 of a sleeve 38 by a countersunk-head bolt and are held against rotation by a rod 49 passing across all the blades and bearing on a shoulder 48. The bolts are moved down by a laterally-movable member having an inclined surface engaging an inclined surface at the bottom of the holder or by flexible hoses 57 which can be expanded by oil forced in by an oil cylinder. Scribing knives may be welded to the spacer members.