| 摘要 |
PROBLEM TO BE SOLVED: To provide a magnetic sensor device capable of determining whether a magnetic pattern affixed to a medium is a hard material or a soft material.SOLUTION: A magnetic sensor device 20 has a sensor part 1 for detecting a magnetic pattern M of a medium 3 conveyed along a conveyance surface 2. The sensor part 1 includes: a permanent magnet 5 for applying a bias magnetic field 4; a downstream side yoke 6 arranged on the downstream side of the permanent magnet 5; a first magnetism-sensitive element 11 arranged at a first position A facing the downstream side yoke 6 in an orthogonal direction Z orthogonal to the conveyance surface 2 but not facing the permanent magnet 5; and a second magnetism-sensitive element 12 arranged at a second position B facing the permanent magnet 5 in the orthogonal direction Z. The first magnetism-sensitive element 11 detects a change only of a bias magnetic field 4 due to remnant magnetic flux density of the magnetic pattern M (hard material), and for this reason, it can be determined whether the magnetic pattern M provided for the medium 3 is a hard material or a soft material.SELECTED DRAWING: Figure 1 |
