| 摘要 |
<p>The present invention relates to a drill for chip removing machining, the drill comprising a front tip (13) having at least one cutting edge (1) as well as a chip flute (7) being countersunk in an envelope surface and extending rearwardly from the cutting edge (1), said flute being generally defined by a cross-section-wise concavely vaulted surface (17) located between longitudinal borders, a first one of which extends from the area of a peripheral end of the cutting edge (1) Characteristic of the drill is that the chip flute (7) is deeper in the area of the first border than in the area of the other border inasmuch as a curve defining the cross-sectional shape of the flute surface (17) has a radius of curvature, which is smallest in the vicinity of the first border and interceases towards the other border, and that the flute surface, in front, transforms into a planar surface (10), which in turn transforms into said cutting edge (1).</p> |
