Hand-guided core drilling machine for drilling centering borehole in metallic workpiece, has crown drill bit that is driven with first gear element, and pilot drill bit which is driven with second gear element of gear box

摘要

The hand-guided core drilling machine (10) has a motor (18) that is coupled with a drilling spindle (38) through a gear box (19). A tool receiver (20) is arranged at the drilling spindle for receiving a crown drill bit (22). A centering retainer (27) is provided for retaining a pilot drill bit (23) coaxially with the crown drill bit. The gear box is provided with a first gear element having a first gear ratio and a second gear element having a second gear ratio. The crown drill bit is driven with the first gear element and the pilot drill bit is driven with the second gear element.