摘要 |
<p>The invention relates to a tool holder on a drill transmission for tubular drilling tools having at least two different diameters, wherein the holder is equipped with a hollow-cylindrical recess and with at least one radially oriented locking bolt which is installed in the wall of the hollow-cylindrical recess and which engages in a corresponding opening in the drilling tool, wherein there is at least one further hollow-cylindrical recess which is complementary to one of the different drilling tools.</p> |