摘要 |
A measuring method and a measuring apparatus for accurately measuring an initial imbalance deviating from a predetermined imbalance, when the predetermined imbalance is to be left in a body of rotation. Data relating to the predetermined imbalance is stored in a memory 22 as a dummy value information. The vibration of a crank shaft 1 as the body of rotation is detected by vibration sensors 6L. 6R so as to obtain analogue vibration signals WDL, WDR. The rotational angle position of the crank shaft 1 is detected by a photo sensor 8 and, in response to this rotational angle position, the above described dummy value information is converted to analogue dummy signals DLX, DLY, DRX and DRY by multi D/A converters 12L, 12R, 13L and 13R and these signals are removed from the analogue vibration signals so as to obtain analogue initial imbalance signals WL, WR, which are converted by D/A converter so as to obtain the digital initial imbalance value.
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