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引用第10楼franco于2009-05-07 20:39发表的 :
# X& g1 N3 Y+ B g6 x$ D9 u* LThe oscillating member is moved backwards and forwards through an angle of 90° (45° on
3 E3 n+ u& }$ r" heither side of the vertical), the number of flexings being 20 000 and the rate of flexing 60 per
8 w, q. j, Z, |+ kmin. A flexing is one movement, either backwards or forwards. After 10 000 flexings, the . e* {& X) F3 x
sample 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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4 R8 W3 |8 K' H2 }, J z翻译成中文的主要意思就是:" y- F/ h4 |) a: \. Q
. W7 D$ T4 N/ |# t8 u6 x3 @+ i( n; LThe oscillating member is moved backwards and forwards through an angle of 90° (45° on y* y7 k# k( O% A
either side of the vertical), the number of flexings being 20 000 and the rate of flexing 60 per - s% [ }3 u. I: z
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。 m9 ~: S* |% U. x8 X x" |
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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。' Q0 S" z& \" c
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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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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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5 @0 S5 q: B6 L |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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4 [$ i0 g+ Z, o# P1 ^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°。+ C0 v% m1 H9 E Z1 s/ e3 B, L4 X. l
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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:$ R, U6 b4 y- c
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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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