HAMMER DRILL FOR PERFORMING ROTARY DRILLING OR PERCUSSIVE DRILLING

摘要

A hammer drill for performing percussive drilling or rotary drilling includes a housing and a tool holder mounted on and axially displaceable relative to the housing, the tool holder contains a retainer sleeve having locking members for securing the shank of a tool in the holder. When the hammer drill is used only for rotary drilling, the retainer sleeve is displaced into contacting engagement with the housing for centering the tool holder. The tool holder includes stops for securing the locking members against axial displacement during rotary drilling. One stop is movable relative to the retainer sleeve and can be locked in position. Another stop forms part of the retainer sleeve. The stops combine with the closed ends of recesses in the tool shank for holding the locking members against axial displacement.