Drilling and turning-out tool

The drilling and turning-out tool has a housing (3), provided at the front end of a holder shank (2), and a slide (4) displaceable in the housing (3) radially relative to the holder-shank axis (A) by means of a threaded spindle (5). The latter bears against the inner face (7a) of a cover plate (7) closing off the housing (3) at the front and has a cylindrical locating pin (9) projecting forwards through a recess (8) of the cover plate (7) and serving for receiving a tool shank. A tool shank (10a) surrounds the locating pin (9) by means of a locating bore (11) and bears with an annular face surrounding the locating bore (11) against the end face (7b) of the plane-parallel cover plate (7). The tool shank (10a) has, in the region of the locating bore (11), two diametrically opposed, radially extending internal threads (13, 14), each with a clamping screw (15, 16) provided with a conical extension (15a) or with a conical depression (16a). Radially displaceable in a transverse bore (17) of the locating pin (9) is a clamping bolt (18) which has at each of its two ends respectively a conical depression (19a) and a conical extension (19b) co-operating with the conical extensions (15a) and depressions (16a) of the clamping screws (15, 16). The distance (a1) between the axis (A1) of the internal threads (13, 14) and the annular face (12) is somewhat greater than the distance (a2) between the axis (A2) of the transverse bore (17) and the end face (7b), so ... Original abstract incomplete.