| 摘要 |
The door is made from horizontal louvres, or slats, jointed to enable it to be wound onto the polygonal cross-section drum (1) on the top of the cabin roof. The widths of the slate increases for each group of slats comprising one layer on the drum to allow even winding. The edges of the slats are guided in tracks inside the cabin and a counterweight system (8) balances the door. The counterweights are loosely threaded on a support cable and are in increasing diameters towards the top. The weights are caught by flanges in the sides of the ballast weight tube to reduce the counterweight progressively as the door is wound onto the drum. ADVANTAGE - Can be retrofitted to avoid use of doors. Compact, does not encroach on room in cabin. |
