| 摘要 |
PURPOSE:To effectively reduce the inherent vibration noise of a wt. detector, by a simple constitution such that the cut-off frequency of a switched capacitor filter is changed corresponding to the wt. of an article to be measured. CONSTITUTION:When a at. detector 1 is in a non-load state, the cut-off frequency of a switched capacitor filter 3 is set so as to be almost coincide with the inherent vibration frequency of the detector 1 at that time and, when an article to be measured is placed, the inherent vibration frequency of the detector 1 reduces corresponding to the wt. thereof. A microcomputer 7 allows the cut-off frequency of the filter 3 to change through a D/A converter 9 and V/F converters 81, 82 on the basis of a measured wt. inputted successively according to a predetermined conversion table or an operation formula so as to follow the change in frequency. As a result, the high noise component of a signal level can be effectively attenuated without lowering a weighing speed.
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