| 摘要 |
<p>In the wall of a sealed zone is a chamber formed by a tubular casing. Each end of the casing is provided with a frame, which supports a hinged door. Each of the two doors can be opened or closed by a jack, whereas a second jack (I) is used to lock each door. The two second jacks (I) are each operated by a hand lever linked to a control box mounted in the frame at each end of the casing. The two control boxes each contain meshing pinions and an air valve; and are connected together by a link rod. The link rod and control boxes ensure that one door can only be opened when the other door is closed and locked. The air valves are used to ensure that no contaminated air can enter the chamber when the latter is being swept by clean air. Simple and reliable, and with a lower cost than similar conventional air lock chambers.</p> |
