| 摘要 |
A percussive blow assisted rotary drill, has an axially extending shank (1) with a leading end face (3) and an axially extending outside surface (2) with helically extending drilled material removal grooves in the outside surface. A hard metal main cutting plate (6) and hard metal auxiliary cutting plates (11) are seated in an axially extending leading end region of the shank and are arranged in an X-shaped pattern. The main cutting plate and auxiliary cutting plates project axially outwardly from the leading end face (3) and radially outwardly from the outside surface (2). The auxiliary cutting plates project axially and/or radially outwardly beyond the main cutting plate and, relative to the rotational direction (R) of the drill, the auxiliary cutting plates and the main cutting plate lagging the auxiliary cutting plates form an acute angle. The main drilled material removal grooves are located upstream, relative to the rotational direction, of the auxiliary cutting plates.
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