| 摘要 |
PURPOSE:To constitute a titled detector so that its detecting output is scarcely varied even if a distance between a sample consisting of a magnetic material and a magnetic core is varied, by forming it with two magnetic cores having opposed two faces, two windings wound round them and an inductance detecting circuit. CONSTITUTION:Channel shaped magnetic cores 11, 12 having the same size and shape have opposed two faces S1 and S2, and S3 and S4 to each other at a distance y0. A winding 21 and 22 are connected in series, and are connected to a terminal 210 and 220. An inductance detecting circuit 600 for supplying an AC current to the winding 21 and 22, and detecting the sum L of inductance of these windings 21, 22 is connected to the terminal 210 and 220. If both the magnetic cores 11, 12 are energized, magnetic flux density in air-gaps 110, 120 is equalized, comparing with the case when only the magnetic core 11 is energized. Accordingly, by this equalization, even if a distance (y) between a bank note 5 printed in ink containing a very small quantity of magnetic material is varied, the inductance L is scarecely varied, and also a detecting output of the detecting circuit 600 is scarcely varied. |
