摘要 |
In a two-part drilling tool for the percussive or rotary percussive drilling of holes in soil material or rock material, comprising a drill head (1) and an adapter part (7), which is fixed in an interior of the drill head (1) by way of interacting, complementary threads (11, 14) and is intended for providing the coupling to a drill string, wherein an end face (3) of the drill head (1) that is remote from a borehole interior rests on a complementarily formed stop surface or supporting surface of the adapter part (7), the end face (3) of the drill head (1) that is remote from the borehole interior and the stop surface or supporting surface of the adapter part (7) that interacts with said end face have complementarily formed tapering surfaces (4, 6) with end teeth (5, 8) and a lead angle (α1) of the tapering surfaces (4, 6) smaller than a lead angle (α2) of an internal thread of the drill head (1) or of an external thread interacting therewith of the adapter part (7) or of the drill string. |