holzmeissel and its manufacture method

摘要

1429297 Making wood chisels; brazing; jointing JACOBS MFG CO Ltd 10 Aug 1973 [5 Sept 1972] 41155/72 Headings B3A B3R and B3V [Also in Division B4] A wood chisel is made by heat treating, grinding and polishing a blank cut from a hot rolled or drawn metal bar to form a blade 10 and integral shank portion 12, securing the shank portion 12 to a bolster 14 formed from a cheaper metal and fitting a handle 18 to a tang 16 which is integral with the bolster 14. The blade 10 of high quality steel is formed with a shank 12 having a rectangular section or a cylindrical section formed by turning. The shank 12 is releasably retained by a locking screw 24 in a recess 20 of the bolster 14 which is formed of mild steel. Alternatively, the shank 12 is permanently secured to the bolster 14 by force fitting or by brazing, adhesive or plastics material which may be introduced through a hole (32) (Fig. 7, not shown). If the shank 12 is rectangular, the recess 20 of the bolster 14 may be cylindrical and the voids filled with the metal brazing, adhesive or plastics. In another embodiment (Fig. 8, not shown) the bolster 14 is slotted and fitted with a sleeve (28) to form a collet. A portion of the blade 10 is received in a slot 30 in the collet to prevent the blade 10 from turning. The tang 16 of the bolster 14 has a knurled portion 22 and is force fitted into a wooden or plastics handle 18.