Studies on Quantification of Sensuous Sharpness and Mechanical Shapness of Wood Cutting Tools. XVII.Effects of the Length on the Rake Face of the Knife between the Knife Edge and the Chip-Breaker Edge upon Variation of Cutting Force in Oblique Cutting of Wood Parallel to the Grain with the Knife Equipped with a Chip Breaker

摘要

The purpose of this report is to clarify the effects of the inclination angle (i(K)) of the knife, the distance (ℓ(k)) on the knife rake-face from the knife edge to the chipbreaker edge, and the grain angle (φ) of the workpiece upon the variations of the components and the resultant of the cutting force in the oblique cutting of wood parallel to the grain with the knife equipped with a chip breaker. Air-dried specimens of Douglas fir (Pseudotsuga menziesii) were used in this study, and were cut by feeding a knife equipped with a chip breaker, which was set on the same experimental apparatus equipped with a three-dimensional elastic-ring dynamometer as used in the previous reports4)～7). The lateral (Fx), main (Fr), and thrust (Fz) components of the cutting force acting on the knife equipped with the chip breaker were measured. Using the measured components mensioned above, the resultant (R) was calculated. Based on these results, effects of the cutting conditions (i(k) and ℓ(k)) and the workpiece condition (φ) upon the variations of the components and the resultant of the cutting force were clarified (Figs. 11～14). Characteristics of the oblique wood-cutting with a chip breaker are discussed, comparing its cutting with the oblique wood-cutting without a chip breaker and the orthogonal wood-cutting.