GB1140469A - Self-sharpening saw chain - Google Patents

Abstract

1,140,469. Sawing. McCULLOCH CORP. 29 Dec., 1966 [4 Jan., 1966], No. 58139/66. Heading B5L. A saw chain cutter link comprises a flat link body portion 12, and a cutter element 18 having top 20 and outer side surfaces 22 hardened throughout their length in the direction of cutting, the element inwardly of said surfaces being progressively softer so that, during cutting, abrasion occurs on the leading end of the element in progressive amounts inwardly of the surfaces 20, 22 in accordance with the varied inwardly progressive softness of the element so that the leading end of the element retains an inclined and bevelled surface. The forward end of the body portion 12 has a depth gauge 15 and the cutter element 18, which is integral with or welded to the portion 12, has a cutting edge 18a on its side surface 22 and a cutting edge 18b on its top surface 20. The element 18 is inclined downwardly and rearwardly. The surfaces 20 and 22 may be hardened by a carbonizing or induction hardening process and the body of the element has successively softer layers A, B, ... E until the core 50 is reached. During sawing, the material cut by the link abrades the leading face of the cutter element and wears away the leading face in proportion to its hardness so that the leading edges 18a, 18b retain sharp cutting edges. In another embodiment, the cutter element has the shape of a figure 7.