<論文>インサイジング刃物の圧入力(第1報) : オイスター型刃物によるインサイジング

Abstract

Incising force was investigated with a small oyster type knife edge, using eight wood species including a few impermeable ones which must be incised. Influence of incised surfaces (tangential or radial), incising angles to fiber axis and incision depths on incising force was discussed here and following results were obtained. (1) With the increase in incising angles up to 90°, incising force per width unit of the knife edge (mm) tended to increase in both tangential and radial surfaces. (2) Incising force increased linearly with incision depths in using an oyster type knife edge (Fig. 3). which was quite different from the behaviour in incising force changes obtained by a double edged chisel. (3) The incising force changes, especially in the tangential surfaces, were characterized by the width of late wood of each wood species, and classified into four types according to wave patterns (e.g. calms, ripples, wavelets and surges) of figures showing the relation between incising force and incision depths. (4) Correlation between incising force in both tangential and radial surfaces and specific gravity of wood seemingly existed. However, as to Beimatsu and Karamatsu with high specific gravity, the decrease in incising stresses was accompanied with the occurrence of cracks in the woods when larger incising angles to fiber axis were employed in the tangential surface. The result suggested that any correlation between incising force and specific gravity could not be perceived with those timber species at larger incising angles (above 60°). (5) In the case of radial surface incision, slopes of the regression equations as shown in Fig. 2 were indicative of a good correlation with specific gravity of wood.