| 摘要 |
<p>PROBLEM TO BE SOLVED: To prevent the malfunction of a metal detector and detect the most minute metal piece by detecting presence or absence of a mixed metal by a metal detector after electrically neutralizing with ions of an ion generator the static electricity which an inspected body is charged with. SOLUTION: A metal detector 12 is disposed in a carrying path of a carrying belt 11 that carries a specimen 10, and a discharge type ion generator 20 is disposed on an upstream side of the metal detector 12. The discharge type ion generator 20 is connected to a high-voltage generator 21, an air passing between high-voltage positive and negative electrodes 22 and 23 is ionized, and this ion blows the specimen 10 and electrically neutralizes static electricity. An ion generation state is sensed by an ion sensing sensor 24, and an optimal ion generation is made possible by feeding back the result to positive and negative electrodes 22 and 23 via the high-voltage generator 21. Consequently, static electricity generated by mutual friction of the specimen 10 or friction between a carrying belt 11 and a roller 13 is neutralized by ion and erased.</p> |
