发明名称 |
Adjustable springs for trampolines and the like |
摘要 |
The typical helical springs used to support the bed within the frame of a trampoline or the like are modified to incorporate adjustable hooks threadedly anchored within the springs at one end so that their overall length, and thus the tension on the bed, can be varied and overstretching accommodated. Two principal versions are disclosed, the more preferred one including an additional inner spring biasing the adjustable hook to a retracted position.
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申请公布号 |
US4162063(A) |
申请公布日期 |
1979.07.24 |
申请号 |
US19760649508 |
申请日期 |
1976.01.15 |
申请人 |
NISSEN CORP |
发明人 |
KELLY, HARLAN J;NISSEN, GEORGE P |
分类号 |
A63B5/11;(IPC1-7):A63B5/18;F16F1/12 |
主分类号 |
A63B5/11 |
代理机构 |
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代理人 |
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主权项 |
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地址 |
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