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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 :
6 ]* m# h- j$ u" l- w0 hThe oscillating member is moved backwards and forwards through an angle of 90° (45° on
1 \' I( }& l7 y0 Heither side of the vertical), the number of flexings being 20 000 and the rate of flexing 60 per
8 ?, W: Z$ ?% a) |2 \4 C$ bmin. A flexing is one movement, either backwards or forwards. After 10 000 flexings, the 0 H2 v& F% r/ A( u, i- C
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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* p4 H) y* [, |翻译成中文的主要意思就是:& P% |' ]4 k' T% G; M; v( Y
; |3 J4 X* [, O/ z6 I- d! i! i( VThe oscillating member is moved backwards and forwards through an angle of 90° (45° on
+ \% D) I# z' C4 @& G/ Xeither side of the vertical), the number of flexings being 20 000 and the rate of flexing 60 per h$ i4 W* ], o4 Y+ S( z+ ^ b8 w- 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。
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& y, J* b2 }6 P. j: {) j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。
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+ V" c% Z# {5 k* d3 GAfter 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。) ^; ~/ Z2 B9 F5 L* u: H
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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。! `; {1 ~$ Z. N$ L1 z4 x7 j
/ y' r6 b! H! S5 X6 J, 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°。
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) k/ R3 R9 z1 W* \/ 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:8 m( P8 ] {4 k4 |: L
/ W0 R- N. ?: dA 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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