| 摘要 |
933,770. Cutting-tools and tool-holders. K. HERTEL. Nov. 30, 1959 [April 30, 1959], No. 40547/59. Class 83 (3). [Also in Group XXV] A bit 16, Fig. 4, for a cutting tool has square, parallel, end surfaces 23, 23a twisted relatively about the axis of a screwed fixing hole 19. The sides have triangular areas 28 ground off to remove the corners, and the bit is supported in a recess 15 in the holder, the surfaces 24, 26 of which are undercut. The bit is fixed by a screw 21, Fig. 7, and has eight cutting edges which can be positioned for use. In another arrangement, the bit 51, Figs. 10, 11, is in two separate parts 41, 41a of truncated-pyramid forms which are fixed together by a rivet 58a to form a bit similar to that of Fig. 4. The rivet has a screwed fixing hole 68 and projections 49a to prevent relative turning of the parts. The sides of each part may have clip-leading steps 42a, Fig. 13. In yet another arrangement, the bit 70, Fig. 16, is secured in a recess in a holder 69 by a bifurcated strip 79 slidable in an arcuate channel 83 in the holder to engage under a head 80 on a pin 74 passed through the bit, and clamped by a screw 82. |
