Rock drill cylindrical cover

摘要

The cover base (2) connects to the under edge of the cover (6) and extends inwards, having a circular aperture in its centre. The bucket base (1) has excavating tools on its lower face (3a). In the closed state of the rotary drill bucket is tightly closed. The cover (6) with the base fixed to it is vertically movably located relative to the rotary drill bucket base. The tools (3a) on the rotary drill bucket are so arranged, that on drilling the excavated material is conveyed radially/spirally outwards. The other tools (3b) on the cover base (2) are so arranged that on drilling the excavated material is conveyed radially/spirally inwards.