| 摘要 |
An access tower has two mutually spaced side parts extending from a base part to the top part; and inclined cross parts each extending from one side part to the other. The cross parts are arranged one above another and inclined in opposite senses. The cross parts are rigid and are connected to the side parts. The lower one of two successive oppositely inclined cross parts has its upper end connected to an articulation node to which the lower end of the upper one of said two successive oppositely inclined cross parts is connected. A section of the side part opposite said articulation node, which section extends between the upper end of said upper cross part and the lower end of said lower cross part, is collapsible so that said upper cross part together with the portion of the tower above it can be lowered into a position in which said upper cross part extends substantially parallel to said lower cross part. A releasable locking device is provided to prevent collapse of said collapsible section.
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