公开(公告)号：US20190128699A1

公开(公告)日：2019-05-02

申请号：US16123513

申请日：2018-09-06

Applicant: TDK CORPORATION

Inventor： Keisuke UCHIDA ,  Tsuyoshi UMEHARA ,  Toshihide SUTO ,  Hiraku HIRABAYASHI

IPC: G01D5/16

Abstract: A position detection device includes a first magnetic field generation unit for generating a first magnetic field, a second magnetic field generation unit for generating a second magnetic field, and a magnetic sensor. The position of the second magnetic field generation unit relative to the first magnetic field generation unit is variable. The magnetic sensor detects the direction of a target magnetic field at a detection position in a reference plane. The target magnetic field is a composite magnetic field of first and second magnetic field components which are respective components of the first and second magnetic fields parallel to the reference plane. The magnetic sensor includes a magnetoresistive element including a free layer and a magnetization pinned layer. In the reference plane, two directions orthogonal to the magnetization direction of the magnetization pinned layer are each different from both of directions of the first and second magnetic field components.

公开(公告)号：US20180356473A1

公开(公告)日：2018-12-13

申请号：US15992411

申请日：2018-05-30

Applicant: TDK Corporation

Inventor： Yohei HIROTA ,  Hayato MIYASHITA ,  Tsuyoshi UMEHARA ,  Hiraku HIRABAYASHI

IPC: G01R33/09

CPC classification number: G01R33/093 ,  G01R33/096 ,  G01R33/098

Abstract: A pair of bias magnets applies a bias magnetic field to the magneto-resistive effect element, the bias magnetic field having a component in a direction such that the component cancels the external magnetic field that is applied to the magneto-resistive effect element and a component that is perpendicular to the external magnetic field. The bias magnet has an elongate cross section in a plane that is parallel both to the external magnetic field and to the bias magnetic field. In a projection plane that is parallel to the cross section and onto which the bias magnets and the magneto-resistive effect element are projected, the bias magnet includes an element facing side that is opposite to the magneto-resistive effect element and that extends in a longitudinal direction. The bias magnet is magnetized in a direction that is perpendicular to the longitudinal direction. The element facing side is longer than other sides.