POSITION DETECTOR

摘要

PROBLEM TO BE SOLVED: To provide a position detector that has a small variation of signal output with respect to displacement of magnetic flux density detection means.SOLUTION: A position detector includes: a Hall IC 60 that is provided in a mold portion 9 so as to be relatively movable with respect to a rotor 12 in an opening 101 between a first magnetic flux transmitting portion 20 and a second magnetic flux transmitting portion 30 and that outputs a signal corresponding to density of a magnetic flux through which the Hall IC 60 passes; a first magnetism collecting portion 70 that is provided on a first magnetic flux transmitting portion 20 side of the Hall IC 60; and a second magnetism collecting portion 80 that is provided on a second magnetic flux transmitting portion 30 side of the Hall IC 60 so that the Hall IC 60 is interposed between the second magnetism collecting portion 80 and the first magnetism collecting portion 70. In the position detector, magnetic reluctance of a first magnetic path M1 serving as a magnetic path between the first magnetism collecting portion 70 and the first magnetic flux transmitting portion 20, and magnetic reluctance of second magnetic path M2 serving as a magnetic path between the second magnetism collecting portion 80 and the second magnetic flux transmitting portion 30, are set so that the Hall IC 60 is relatively movable with respect to the rotor 12 at a position in a radial direction of a first virtual arc C1 in the opening 101 at which magnetic flux density becomes minimum.