The principle of magnetic sensors

The path of the magnetic field lines passing through the N pole of the permanent magnet rotor a stator and a rotor air gap between a rotor lobe and stator lobe air gap between the magnetic head a head-S a permanent magnet magnetic pole plates. When the signal rotor rotates, the air gap of the magnetic circuit will be changed periodically, through the magnetic circuit and the magnetic flux along Engine Water Temperature Sensor coil changes periodically. According to the principle of electromagnetic induction, inductive sensing coil will produce alternating electromotive force. Since the rotor lobe air gap between the magnetic head magnetic circuit and directly affect the output voltage level of the sensing coil, so the use of the rotor lobes and the air gap between the magnetic head can not be arbitrarily changed. Gap are subject to change, it must be adjusted according to regulations, the air gap is generally designed in the range of 0.2 ~ 0.4mm.