To make the voltage of an output signal which occurs owing to external a.c. magnetic fields approximately zero.
A correcting coil 317 is wound in a direction opposite to that of the winding of a detecting coil 313 which detects changes in the amount of magnetic flux due to the rotation of a pulser ring 311. The correcting coil 317 is arranged at a location in the vicinity of the detecting coil 313 where the amount of passing magnetic flax hardly changes even if the pulsar ring 311 is rotated so that the axis of the correcting coil 317 may be in parallel with the axis of the detecting coil 313. The correcting coil 317 and the detecting coil 313 are connected in series. The number of the winding of the correcting coil 317 is equated with the number of the winding of the detecting coil 313, and the same level of voltages opposite in voltage polarity are generated in the coils 313 and 317 by external a.c. magnetic fields so as to cancel out each other. It is preferable to arrange an auxiliary yoke 319 on the side of the inner diameter of the correcting coil 317.
| JPH09505177 | [Title of Invention] Magnetic Field Detection Device |
| WO/2015/162414 | GENERATING TIMING SIGNALS |
| JP3552371 | Waveform shaping circuit |
NAKANO TOMOHIKO
HIRAIWA YUJI
| JPS58163347A | 1983-09-28 | |||
| JPS6313500A | 1988-01-20 |
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