摘要 |
A method and an apparatus for picking up a fabric workpiece by applying vacuum provides two vacuum sensors; one for a sample fabric and the other for a fabric workpiece to be picked up. Where the apparatus has picked up incorrect number of sheets, the two vacuum sensors will output different voltages and the values are converted from analog to digital and input to a comparator. Thus, in such a case, the comparator outputs particular signals to stop the picking-up action of the apparatus.
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