| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a magnetic substance detecting device wherein, even if the distance between a care and a magnetic substance changes, fluctuation of detection signal is less and the detection signal proportional to the amount of magnetic substance is obtained, and identification of place is possible, being stable in temperature change. SOLUTION: Relating to a J-like cores 2 and 5, open ends 2a and 5a, and, 2b and 5b, their lengths being different, are assigned to face each other with a specified gap. Coils 3 and 6 wound around longer open ends 2a and 5a, respectively, are connected in series to form a coil 100. Coils 4 and 7 wound around shorter open ends 2b and 5b, respectively, are connected in series to form a coil 200. The detection signal from the coils 100 and 200 is introduced into a signal processing circuit, and impedance change in magnetic substance on a sheet 8 is detected.</p> |
