ROTATION ANGLE DETECTION DEVICE

• Main Authors: YANAI OSAMU, SHIINO KOTARO
• Format: Patent
• Language: English; Japanese
• Published: 10.05.2018
• Subjects: ARRANGEMENTS FOR MEASURING TWO OR MORE VARIABLES NOT COVEREDIN A SINGLE OTHER SUBCLASS; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER; DYNAMO-ELECTRIC MACHINES; ELECTRICITY; GENERATION; MEASURING; MEASURING NOT SPECIALLY ADAPTED FOR A SPECIFIC VARIABLE; MEASURING OR TESTING NOT OTHERWISE PROVIDED FOR; PHYSICS; TARIFF METERING APPARATUS; TESTING

PROBLEM TO BE SOLVED: To provide a rotation angle detection device that allows for suppression of reduction in detection accuracy thereof.SOLUTION: A rotation angle sensor 5 (a rotation angle detection device) for detecting a rotation angle of a motor shaft 20 (a rotor) is provide that comprises: the motor shaft 20 that rotates around a rotation axis line O; a magnet holder 8 that is provided on one end side of the rotation axis line O in the motor shaft 20, is formed of a magnetic material and a resin material, and has a magnet accommodation part 80 extending in a direction of the rotation axis line O and being a cylindrical part; a magnet 7 that is provided inside the magnet accommodation part 80, and is provided in such a manner that an N pole and S pole are juxtaposed in a circumferential direction of the rotation axis line O; and an MR element 50 (a magnet sensor) that is provided so as to oppose the magnet 7, and detects a change in a magnitude or a change in a direction of a magnetic field of the magnet 7 caused by rotation of the motor shaft 20 to thereby detect the rotation angle of the motor shaft 20. The magnet holder 8 is formed in such a way that the resin material encloses at least a part of the magnetic material.SELECTED DRAWING: Figure 2 【課題】 検出精度の低下を抑制できる回転角検出装置を提供すること。【解決手段】 モータシャフト20（回転体）の回転角を検出する回転角センサ５（回転角検出装置）であって、回転軸線Oを中心に回転するモータシャフト20と、モータシャフト20において回転軸線Oの一端側に設けられ、磁性材料と樹脂材料で形成され、回転軸線Oの方向に延びる筒状部であるマグネット収容部80を有するマグネットホルダ８と、マグネット収容部80内に設けられ、回転軸線Oの周方向においてN極とS極が並ぶように設けられたマグネット７と、マグネット７と対向するように設けられ、モータシャフト20の回転に伴うマグネット７の磁界の大きさの変化または方向の変化を検出することによりモータシャフト20の回転角を検出するMR素子50（磁気センサ）と、を備え、マグネットホルダ８は、樹脂材料が磁性材料の少なくとも一部を包囲するように形成される。【選択図】 図２