PERMANENT MAGNET USED FOR MEASUREMENT OF DISPLACEMENT, DISPLACEMENT AMOUNT SENSOR UNIT, AND MANUFACTURING METHOD THEREFOR

Title:

PERMANENT MAGNET USED FOR MEASUREMENT OF DISPLACEMENT, DISPLACEMENT AMOUNT SENSOR UNIT, AND MANUFACTURING METHOD THEREFOR

Document Type and Number:

Japanese Patent JP2007093569

Kind Code:

A

Abstract:

To attain high accuracy for a displacement amount sensor unit, by eliminating error in the displacement amount sensor due to magnetization and machining part.

A rotation angle sensor unit comprises a rotor which forms a magnetic field in the circumferential direction in the magnetic flux density distribution, a magnetic sensor which detects the magnetic flux, or the magnetic field or the magnetic flux density generated by the rotor. The rotor is constituted of a plurality of anisotropic magnet pieces, for adjacent magnet piece, the orientation directions are different mutually. Variation in the magnetic pole pitch can be decreased, when the rotor is formed and its magnetization procedure is performed, even if there are variations in the position of the magnetization winding.

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Inventors:

MITA MASAHIRO
MASUZAWA MASAHIRO
AIMUTA KYOHEI
ABE TAISUKE

Application Number:

JP2005311924A

Publication Date:

April 12, 2007

Filing Date:

October 26, 2005

Export Citation:

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Assignee:

HITACHI METALS LTD

International Classes:

G01D5/245; H01F7/02; H01F41/02

Domestic Patent References:

JP2003217929A

2003-07-31

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