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发表于 2009-5-8 15:06
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引用第10楼franco于2009-05-07 20:39发表的 :
- ^$ F& \3 M/ M$ tThe oscillating member is moved backwards and forwards through an angle of 90° (45° on * m" t1 U8 {9 X* T8 c% k4 b+ Q
either side of the vertical), the number of flexings being 20 000 and the rate of flexing 60 per / o2 v. Y& e5 [/ n s) A; @
min. A flexing is one movement, either backwards or forwards. After 10 000 flexings, the
0 V% s& Q; T% o# D3 n2 t8 Asample is turned through 90° about the centre line of the cord guard. ' { e- O! Y8 i1 X; _+ J* m
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.......
3 ~; K1 n9 Q. J) U+ C( L翻译成中文的主要意思就是：6 d7 c6 b* s4 r- F8 K6 Y
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The oscillating member is moved backwards and forwards through an angle of 90° (45° on : D& M/ a1 V* T; \! q4 D
either side of the vertical), the number of flexings being 20 000 and the rate of flexing 60 per 1 V$ v, W( u) X# ^2 x$ O
min. - 摇摆装置能够在90°的范围内前后摆动（其中这个90°指的是沿垂直位置两边各45°），以每分钟60次的频率摇摆20000次。 ?4 G; h$ y: U a1 g; B
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这句话讨论的是仪器的摆动机构要满足的特性，就是要能在90°的范围内前后摆动，如果只能在45°的范围内摆动的话，这个设备就是不符合要求的。这句话并没有涉及到一个摆动周期如何定义啊。, b C' ~7 S% d6 H
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After 10 000 flexings, the sample is turned through 90° about the centre line of the cord guard. - 10000次摆动之后，将样品沿着电线防护套的中心线转动90°。( B, o! Z. H* s" f
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这句话说的是总共20000次的摆动样品应该在两个位置分两次完成而已，同样没有涉及到摆动周期的解释和说明。
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! q. K! T! J+ j; u1 u& A B最重要的一句话应该是：A flexing is one movement, either backwards or forwards. - 一次摇摆就是一次移动，无论是向后还是向前的。& h! {, R! {2 }# [3 c
* _/ q6 ]3 \% B" A" Z: @这句话虽然容易引起歧义，但是仔细考虑一下也不是很难理解。可以看出，1个摆动周期就是单次的向前或者向后的移动。摇摆机构是在总共90°范围内摆动，那不管是向前还是向后的摆动角度都是45°了。由此可以得出1个摇摆周期就是45°而不是我们通常认为的90°。$ H) |2 `8 V4 d3 o
# n$ G" [2 f9 Y摘抄UL 745-1标准中的相关章节如下，关于这个问题解释的非常清楚，供大家参考参考：
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A flexing is one movement, either backwards or forwards. That is, from vertical to 45° in one direction is the first flex, from there back to vertical is the second flex, from vertical to the opposite 45° is the third flex, from there back to vertical is the fourth flex, continuing until 10000 flexes have occurred. |
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发表于 2009-5-7 20:39
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