| 摘要 |
A child's swing operated by a spring motor. The swing includes a frame, upstanding legs supporting the frame and a swing seat suspended from the frame. The spring motor includes a coiled spring having one end secured to a ratchet wheel and the other end secured to the frame. A pair of pawls alternately engage the ratchet wheel, thereby controlling the release of the tension on the spring. The power of the spring in turn drives the seat in a reciprocating pivotal movement. The spring is formed from spring steel, and has a square cross-section. By utilizing the square cross-section, a spring of increased diameter can be used without the coils of the spring skewing. The increased diameter of the main coiled spring permits the swing to operate for at least twice as long as the prior art automatic swings which were powered by coiled springs.
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