| 摘要 |
<p>A fume exhauster apparatus is provided to permit generation of two air currents. The first air current has a cylindrical shape and is concentrically surrounded by the second air current which has a tubular shape. The first generated air current is directed axially toward the fume exhauster apparatus and the second air current is directed circumferentially and axially away from the exhauster. The second air current is generated in an annular air passage. The apparatus further provides for exchange of interior and exterior air if necessary during operation of the fume exhauster as well as means for preserving the integrity of the second air current when the fume exhauster apparatus is used in close proximity to a vertical wall.</p> |
