| 摘要 |
<p>1534462 Drill dust suppressor G EDWARDS D MORGAN E G HOWELLS and G H GOODHAND 5 Aug 1977 33012/77 Heading B3C [Also in Divisions B4 and F4] A dust suppressor for an air flushed rotarypercussive rock drill comprises a cowl 16 blanked off at one end by a plate 17 formed with an aperture for a drilling rod 12 and open at its other end to enclose the entry of a hole drilled by the drill, a vent pipe 18 projecting laterally from the side of the cowl and spray means for injecting a liquid spray into the vent pipe so that the spray is directed away from the cowl, the spray means comprising a liquid pipe 20 disposed co-axially within a compressed gas pipe 21 whose outlet end projects beyond that of the liquid pipe.</p> |
