| 摘要 |
PROBLEM TO BE SOLVED: To miniaturize a sensor while a shield member for preventing a detection of a rotation angle from being affected by an effect of an external magnetic field is configured so as not to affect an output characteristic of the noncontact rotation angle detecting sensor. SOLUTION: The noncontact rotation angle detecting sensor comprises: a ring-like permanent magnet 20 integrally rotated with a to-be-detected object; a ring-like magnetic field collecting yoke 30 for surrounding an outer circumference of the permanent magnet 20 through a regular gap; and a hall element 40 disposed in a gap X formed by dividing the magnetic field collecting yoke 30 into two pieces along a diameter line. The first and second lateral magnetic shields 50c, 50d surround an outer circumference of the magnetic field collecting yoke 30 through a regular gap. The upper magnetic shield 50a is disposed above an upper face of the magnetic field collecting yoke 30 through a regular gap. The lower magnetic shield 50b is disposed below a lower face of the magnetic field collecting yoke 30 through a regular gap. The first and second lateral magnetic shields 50c, 50d, the upper magnetic shield 50a and the lower magnetic shield 50b are separated from each other. A magnetic flux is prevented from entering into the shields. The effect of the external magnetic field does not affect the magnetic field collecting yoke 30. COPYRIGHT: (C)2009,JPO&INPIT
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