| 摘要 |
The rostrum (1) consists of a series of lengthwise modules (2,3,4), each comprising a frame (5,6,7) with a platform (8,9,10), capable of being deployed or retracted by a drive. The drive comprises a drum (19) mounted on one of the modules (2) and able to roll and unroll two cables (24,26) simultaneously, each cable having one end fixed to the drum. The other ends of the two cables are connected to anchoring points (30,37) on the walls (34,41) in front of and behind the rostrum. In a variant of the design the drum can be fixed to one wall and have a single cable passing round a pulley attached to the other wall and returning to the drum.
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