| 摘要 |
<p>The tool has a dust extraction ducting comprising a transparent sleeve (16) which surrounds the free end of the drill bit (13). A flexible shroud (14) is connected to the drilling tool and carries the transparent sleeve at its front end. The shroud has a compressible portion (20) and carries a tube 18 which can be connected to a flexible hose coupling to a vacuum source. <IMAGE></p> |
