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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 :" E+ v3 U6 O1 u9 `, Z9 z Y
The oscillating member is moved backwards and forwards through an angle of 90° (45° on
) s: t6 d# i, l% D8 H+ p. I, S. ]either side of the vertical), the number of flexings being 20 000 and the rate of flexing 60 per - Z/ y7 B( y2 B4 V
min. A flexing is one movement, either backwards or forwards. After 10 000 flexings, the
8 e8 L3 @0 v( O1 \* `9 C: Isample is turned through 90° about the centre line of the cord guard.
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....... 是的,这段话写的确实很明白,但是我估计你还是理解错了。
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9 \! A; [6 F0 \$ c- q# c翻译成中文的主要意思就是:. r8 |! h3 D/ s% _
7 ?6 h( S* L+ a `* ]The oscillating member is moved backwards and forwards through an angle of 90° (45° on 6 f* W3 F; S0 a# H0 y
either side of the vertical), the number of flexings being 20 000 and the rate of flexing 60 per % O: R: i) [2 c# c8 c/ T7 E# Y
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。
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: b+ K/ h+ K% J* u. v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。! @' a3 o( k h: f
+ g% r; h( O ?5 _% |7 b8 Y! e; f, wAfter 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°。2 w$ V' `% d3 _5 i: `2 P6 l
8 t- ?4 k0 h e& q# G% w9 X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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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。
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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°。
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& s+ N' v3 |5 ^/ k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:# k9 g: f$ J% k* Z4 y5 S
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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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