| 摘要 |
A self-erecting collapsible and foldable articulated tubular beam having a pair of thin-walled resiliently flexible tubes joined end to end by spring loaded hinges in a manner such that the beam may be flattened and then folded to locate the flattened tubes in side by side relation, and the beam, when released, springs back to its normal expanded configuration under the action of elastic strain energy and hinge spring energy stored in the flattened and folded beam.
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