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引用第10楼franco于2009-05-07 20:39发表的 :
' n2 Q: \5 D3 L jThe oscillating member is moved backwards and forwards through an angle of 90° (45° on ( X& u) j- i/ n9 k& ?8 |& b2 ]& S
either side of the vertical), the number of flexings being 20 000 and the rate of flexing 60 per
1 q0 \9 F3 v7 ^/ `min. A flexing is one movement, either backwards or forwards. After 10 000 flexings, the
* ?: `: E- ^+ v) i4 xsample is turned through 90° about the centre line of the cord guard.
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# Q' e# k3 d+ N' d8 d2 W- i....... 是的,这段话写的确实很明白,但是我估计你还是理解错了。$ H3 o, a3 s4 Q' M
* s# A7 g0 C- s% A! V7 z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
j/ D! j2 q, ?. jeither side of the vertical), the number of flexings being 20 000 and the rate of flexing 60 per 7 }/ Q5 H* |; ]3 G0 i$ e, c
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。' U% Y9 Y! M1 l* E: @ W" l% _! y- H
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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。
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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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% Z! n) W% Z/ ?8 M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。6 H7 h8 a6 h4 u
1 l9 i, F5 p0 S3 }3 J0 q5 m. @% w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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5 I- l( h" g/ W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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+ A. j. C2 I0 C: S% i b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:* ` P. j8 m' I# R; ?
, z# i) |" _9 f: V9 F# @8 FA 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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