| 摘要 |
<p>PROBLEM TO BE SOLVED: To minimize adhesion of powder to a detection part of a detection means, minimize the cleaning work of the detection part, easily install a dustproof mechanism even in an existing device, to simplify a structure and minimize the adhesion of powder even if the detection means is used for a high-speed counting device. SOLUTION: This dustproof mechanism 10 of a detection means 1 for performing detection work by setting a detection position 9 at a predetermined position of a detection optical path S formed by a detection part 2 and by passing a detected object 7 through the detection position 9. In this case, a potential measuring means 10a for detecting the polarity charged in the detected object 7 and a potential supplying means 10b for applying a potential having the same polarity as the detected polarity of the detected object 7 to the detection part 2 are provided.</p> |
