| 摘要 |
A roller skate intended for jumping includes a two-piece plate of adjustable length for supporting the foot of a skater, a pair of arms pivotally connected to the bottom of the plate, including front arms inclined slightly forwardly and rear arms inclined slightly rearwardly, with rollers on the bottom ends of the arms, and helical springs connecting the back edges of the front arms and the front edges of the rear arms to the bottom center of the plate, so that downward pressure on the skate causes the arms to become more inclined and, when the springs pull the arms together to the less inclined positions, an upward impetus is given to the skater.
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