Drill bit for production of cylindrical undercut boreholes, has tappet guided adjustably in case, where axial movement of tappet is coupled with radial movement of cutting element, and cutting element and tappet integrated as rod

摘要

The bit (1) has a tubular case (2) and a cutting element (6) radially and adjustably guided opposite to the case. A tappet (7) is guided axially and adjustably in the case, where axial movement of the tappet is coupled with radial movement of the cutting element. The cutting element and the tappet are integrated as a drill rod (3). The drill rod is bent as arc-shaped or sharp-edged and the case exhibits a deflecting device (22). The case has a stopper element (16) for attachment at borehole mouth (19). A stopper (10) acts between the rod and case to limit axial relocatability of the rod.