| 摘要 |
The invention relates to a diamond hollow drill (1), the hollow boring head (3) thereof comprising a diamond layer. According to the invention, said boring head (3) is embodied in the form of a boring crown (4) provided with outer recesses e.g. in the form of grooves in the region of the diamond layer, and segments (5) which radially and outwardly protrude in relation to the adjoining boring head element. A countersunk ring (6) which can optionally be applied to the boring head (3) comprises a shell-type opening, the form of which is essentially adapted to the contours of the boring crown (4), comprising recesses for the segments (5) of the boring crown (1). The interaction between the segments (5) determining the outer diameter of the bore hole and the countersunk ring sections protruding in a smaller diametrical region prevents the formation of burrs at the transition between boring and milling. |
