| 摘要 |
<p>PCT No. PCT/GB95/02002 Sec. 371 Date Feb. 24, 1997 Sec. 102(e) Date Feb. 24, 1997 PCT Filed Aug. 23, 1995 PCT Pub. No. WO96/06313 PCT Pub. Date Feb. 29, 1996A jet fan arrangement for ventilating tunnels and the like in which the axis of the fan is positioned at an angle to the supporting surface so as to blow air away from the supporting surface. When the flow of air through the fan is reversed, the angle of inclination of the axis of the fan is automatically changed so that the direction of flow of air remains away from the supporting surface.</p> |
