| 摘要 |
A shrinkable tubular frame is composed of a plurality of curved tubes having the same length and curvature but different diameter for shrinking in a largest-diameter curved tube one after another so as to be become very short when being shrunk. Each two curved tubes are locked by a fixing unit when being extended out. A winding unit for winding back a rope extended in the frame so as to pull the other curved tubes, except a left one, to shrink in the left largest-diameter tube after being extended out.
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