| 摘要 |
<p>A trepanning tool especially adapted for generating a hole in a composite of at least two materials with different moduli of elasticity including a generally cylindrical side wall with a plurality of spaced cutting teeth (24, 54). These teeth include at least one outwardly-directed cutting tooth with front surface (34,64) leading in the direction of rotation, a semi-cylindrical outer surface (32, 62) and an end surface, wherein these surfaces intersect an outer cutting end point (44, 56). The front surface intersects the end surface at an acute angle and forms an outer end cutting edge (38, 68); the front surface intersects the outer surface at an angle not exceeding 90 degrees and forms an outer circumference cutting edge (42,70); the end surface intersects the outer surface at an acute angle and forms an outer trailing edge (48). The tool further includes at least one inwardly-directed cutting tooth (54) with a front surface (64) leading in the direction of rotation, a semi-cylindrical inner surface (68) concentrically disposed about the tool axis, and an end surface, wherein these surfaces intersect at an inner cutting end point (56). The front surface intersects the end surface at an acute angle and forms an inner end cutting edge (68); the front surface intersects the inner surface at an angle not exceeding 90 degrees and forms an inner circumference cutting edge (70); the end surface intersects the inner surface at an acute angle and forms an inner trailing edge (58).</p> |
