| 摘要 |
<p>A device for transfer of fresh air or air mixed with gases, vapors, smaller particles etc. in one or other direction between a stationary place and a moving place. A stationary elongated box is in communication with the stationary place and has a slot in its longitudinal direction and said slot closeable by a tightening band bearing on contact surfaces at each side of the slot and on the outside of the box. A hollow connection body projects through and is movable along said slot and is in communication with the moving place. Said connection body is provided with slide shoe or shoes in the slot and carries a press roller at each end of the slide shoe or at each slide shoe pressing the band against said contact surfaces and backing rollers lifting the band from engagement with the contact surfaces.</p> |
