| 摘要 |
<p>PCT No. PCT/GB95/03041 Sec. 371 Date Aug. 8, 1997 Sec. 102(e) Date Aug. 8, 1997 PCT Filed Dec. 27, 1995 PCT Pub. No. WO96/19937 PCT Pub. Date Jul. 4, 1996The invention provides a shroud (10; 40) for use in apparatus incorporating a cyclonic dust separation divice for separating dirt and dust from an airflow, the shroud (10; 40) having a perforated portion (14; 44) having a multiplicity of perforations (30; 46) for allowing the airflow to pass therethrough. According to the invention, the upstream edge of each perforation (30) meets the upstream surface (28) of the shroud (10) at a sharply defined angle. The invention improves the performance of the dust separation apparatus in conjunction with which the shroud (10; 40) is utilized.</p> |
