| 摘要 |
PURPOSE:To detect ferromagnetic component in sheets or the like without making contact with the sheet, through determining the mean value of outputs from a plurality of magneto-electric conversion elements. CONSTITUTION:Pairs of magnetic reluctance elements (31,32), (33,34)...(3m,3n) are arranged in the direction of scanning of a sheet or the like. These magnetic reluctance elements are biased by a uniform magnetic field produced by a permanents are biased by a uniform magnetic field produced by a permanent magnet or an electromagnet. The outputs from these elements are delivered to a mean value computation circuit 37 which produces a signal corresponding to the mean level of these outputs. According to this arrangement, it is possible to inspect at a high speed the sheet or the like member containing ferromagnetic component to be inspected without requiring direct contact with the latter. |
