| 摘要 |
An improved retractable roller mechanism 20 and method for statically supporting an item 42 upon a support surface 40 in an inoperative state and supporting the item 42 to roll along the support surface 40 in an operative state. The retractable roller mechanism 20 includes a housing 22, a roller frame 24 that is slideably engaged with the housing 22, a spring 30, and a roller 28. The roller frame 24 has reciprocative movement relative to the housing 22, such that the frame 24 has an inoperative position state where the frame 24 is retracted allowing the housing 22 to rest on and statically contact the support surface 40 and an operative position state where the frame 24 is extended such that the housing 22 is not in contact with the support surface 40 allowing the item 42 to roll along the support surface 40.
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