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楼主 |
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 :* y# {; R: r8 l5 @4 B5 m# K
The oscillating member is moved backwards and forwards through an angle of 90° (45° on
2 N& ?2 r- f7 w4 m- v% K3 j! ]) q' eeither side of the vertical), the number of flexings being 20 000 and the rate of flexing 60 per
4 G# h3 U8 ]& z# |0 y6 {min. A flexing is one movement, either backwards or forwards. After 10 000 flexings, the / \5 j5 w, D9 \" W; W) `
sample is turned through 90° about the centre line of the cord guard.
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9 A: L0 @& C0 u7 f8 G; v; U2 O7 \- s....... 是的,这段话写的确实很明白,但是我估计你还是理解错了。4 \- q2 ~: t9 z7 x! Q
9 J2 H+ ?$ e9 T' {6 R- b翻译成中文的主要意思就是:
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The oscillating member is moved backwards and forwards through an angle of 90° (45° on , @$ x& t4 i+ v$ U1 W7 F2 v
either side of the vertical), the number of flexings being 20 000 and the rate of flexing 60 per 3 T5 m9 c m+ y, f0 n
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。; G J! w# b) E8 }% ~) c' ]
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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。% v7 s) Z. H8 N% j' ^
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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°。
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8 B9 _$ {1 R( V6 Z7 u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。0 r, z8 d1 q* X2 y" _
1 G; x) \: {8 s* x0 P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。2 B0 X6 [. Y% D C. F
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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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& n9 M' z5 m7 O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:: G6 ^7 G' V4 M6 Y- ~' `
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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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