| 摘要 |
<p>A drilling dust extraction arrangement 11 includes a shroud 12 adapted to be attached to a drill alignment device to be in use interposed between the alignment device and a work piece to be drilled. The arrangement may include a shroud 12 having a workpiece-contacting face 15 having an outer rim 16, a drilling chamber 17, air inlet channels 18 connecting the drilling chamber to the outer rim and a suction outlet 19 from the drilling chamber. The air inlet channels may be directed tangentially to the drilling chamber and tapered from the rim to swirl and accelerate the airflow.</p> |
