发明名称 |
Extension trestle ladder |
摘要 |
A device for automatically locking the fly assembly of an extension trestle ladder in an extended or lowered adjustment position. The fly assembly is supported to prevent downward movement by a displaceable member which abuts a rung on the fly assembly along a portion of the length of the rung, which member is spring biased for automatic return to locking position.
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申请公布号 |
US4240522(A) |
申请公布日期 |
1980.12.23 |
申请号 |
US19780968210 |
申请日期 |
1978.12.11 |
申请人 |
R D WERNER CO INC |
发明人 |
SHAWKEY, DONALD L;SPEAR, KENNETH J |
分类号 |
E06C7/06;E06C1/12;E06C1/18;E06C1/22;E06C1/39;(IPC1-7):E04G1/30 |
主分类号 |
E06C7/06 |
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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