| 摘要 |
The invention relates to a drill for producing undercuts (36) in non-continuous, cylindrical pilot bores (17), having a drill shaft (12) which corresponds approximately in diameter to the diameter (17) of the pilot bore (17) and at whose tip (11) is at least one side cutter (15) which protrudes radially over its circumference is provided and which can be supported on the bottom (19) of the pilot bore (17) via an oblique face (13) which brings about radial advance of the side cutter (15) when the said drill shaft (12) is acted on axially. For the sake of simplification, the drill is constructed in such a way that the tip (11) of the drill shaft (12) is provided with the oblique face (13) and thus can be supported directly on the bottom (19) of the pilot bore (17) or on a pressure element (14) which is loose from the drill shaft (12) in the pilot bore (17), and that the outer circumference (16) of the drill shaft (12) which lies opposite the side cutter (15) is flattened to a degree which permits the said shaft (12) to be inserted into the pilot bore (17). <IMAGE>
|
