Patents Assigned to Alps Green Devices Co. Ltd.
  • Publication number: 20110221434
    Abstract: A current sensor includes a magnetic detecting element, a bridge circuit including a plurality of resistance elements, and a feedback coil placed adjacent to the magnetic detecting element and generating a cancelling magnetic field for cancelling the induced magnetic field based on the output from the bridge circuit. The wiring patterns forming the bridge circuit are routed so as not to intersect with each other when seen in a plan view. Only the resistance elements constituting each series circuit of the bridge circuit are connected to each other by the wiring pattern in an enclosed area which encloses each resistance element constituting the bridge circuit, and the wiring pattern branched from the wiring pattern is connected to the terminal which is installed in a quantity of only one, outside the enclosed area.
    Type: Application
    Filed: February 28, 2011
    Publication date: September 15, 2011
    Applicant: ALPS GREEN DEVICES CO., LTD.
    Inventors: Yoshihiro NISHIYAMA, Masamichi SAITO, Akira TAKAHASHI, Yosuke IDE, Hidekazu KOBAYASHI, Masahiro IIZUKA
  • Publication number: 20110221436
    Abstract: A current sensor including a magnetic detecting bridge circuit which is constituted of four magneto-resistance effect elements with a resistance value varied by application of an induced magnetic field from a current to be measured, and which has an output between two magneto-resistance effect elements. The four magneto-resistance effect elements have the same resistance change rate, and include a self-pinned type ferromagnetic fixed layer which is formed by anti-ferromagnetically coupling a first ferromagnetic film and a second ferromagnetic film via an antiparallel coupling film therebetween, a nonmagnetic intermediate layer, and a soft magnetic free layer. Magnetization directions of the ferromagnetic fixed layers of the two magneto-resistance effect elements providing the output are different from each other by 180°. The magnetic detecting bridge circuit has wiring symmetrical to a power supply point.
    Type: Application
    Filed: March 1, 2011
    Publication date: September 15, 2011
    Applicant: ALPS GREEN DEVICES CO., LTD.
    Inventors: Kenji ICHINOHE, Masamichi SAITO, Akira TAKAHASHI, Yosuke IDE
  • Publication number: 20110204889
    Abstract: A current sensor includes a magnetic equilibrium sensor including a magnetic sensor element with characteristics changed by an inductive magnetic field from a measurement target current and a feedback coil provided in the vicinity of the magnetic sensor element and generating a canceling magnetic field canceling the inductive magnetic field, a shunt resistor connected to a current line through which the measurement target current flows, and a switching unit switching between shunt resistor detection of sensing and outputting a voltage difference of the shunt resistor, and magnetic equilibrium detection of sensing and outputting a current flowing in the feedback coil in an equilibrium state where current flows in the feedback coil according to the inductive magnetic field and the inductive magnetic field and the canceling magnetic field cancel each other.
    Type: Application
    Filed: February 10, 2011
    Publication date: August 25, 2011
    Applicant: ALPS GREEN DEVICES CO., LTD.
    Inventor: Masatoshi NOMURA
  • Publication number: 20110202295
    Abstract: A current measuring device includes a conductor in which detection target current flows, at least two magnetic sensors that detect change of magnetic field generated when the detection target current flows in the conductor, and a calculation unit that calculates magnitude of the detection target current from an output of the magnetic sensor. At least two magnetic sensors are provided at different distances from the conductor, and the calculation unit acquires distances between the magnetic sensors and the conductor to calculate magnitude of the detection target current using the distances.
    Type: Application
    Filed: February 3, 2011
    Publication date: August 18, 2011
    Applicant: ALPS GREEN DEVICES CO., LTD.
    Inventors: Manabu TAMURA, Masatoshi NOMURA, Masaru KOISHI
  • Publication number: 20110199079
    Abstract: A current sensor includes a magnetic detection element having a resistance value changed by applying inductive magnetic field from measurement target current, a magnetic core provided in the vicinity of the magnetic detection element, and a coil generating magnetic field attenuating the inductive magnetic field. A constant level current in a predetermined range of output voltage of the magnetic detection element flows in the coil, and the measurement target current is detected on the basis of the output voltage of the magnetic detection element.
    Type: Application
    Filed: February 3, 2011
    Publication date: August 18, 2011
    Applicant: ALPS GREEN DEVICES CO., LTD.
    Inventors: Manabu TAMURA, Masaru KOISHI, Masatoshi NOMURA, Hiroyuki HEBIGUCHI
  • Publication number: 20110156798
    Abstract: Magnetoresistive effect elements R1 to R4 are a TMR element or CPP-GMR element. A multilayer film forming the magnetoresistive effect elements is formed to have a width dimension T1 and a length dimension L1 perpendicular to the width dimension T1. The length dimension L1 is longer than the width dimension T1. The width dimension of magnetic field generators of the coil is T2. The multilayer film 31 is positioned within the width dimension T3 of 60% in total of 30% each to the width dimension T2 of the magnetic field generators 3 and 4 of the coil in the direction towards both sides from the center of the width dimension T2 when seen in a plan view.
    Type: Application
    Filed: March 9, 2011
    Publication date: June 30, 2011
    Applicant: ALPS GREEN DEVICES CO., LTD.
    Inventors: Yosuke IDE, Masamichi SAITO, Akira TAKAHASHI, Masahiro IIZUKA, Yoshihiro NISHIYAMA, Hidekazu KOBAYASHI
  • Publication number: 20110080165
    Abstract: A magnetic balance type current sensor measures a measured current which flows in a feedback coil when electrical conduction is provided by a voltage difference according to an induction magnetic field from the measured current and an equilibrium state is reached in which the induction magnetic field and a cancel magnetic field cancel each other. Sensor elements in a pair are arranged at positions with magnetic field from the measured current. The magnetization direction of the pinned magnetic layer in the magnetoresistive effect element of one sensor element is aligned in a forward direction with respect to the magnetic field formed by the measured current. The magnetization direction of the pinned magnetic layer in the magnetoresistive effect element of the other sensor element is aligned in a reverse direction with respect to the magnetic field formed by the measured current.
    Type: Application
    Filed: September 27, 2010
    Publication date: April 7, 2011
    Applicant: ALPS GREEN DEVICES CO., LTD.
    Inventors: Masamichi SAITO, Akira TAKAHASHI, Masahiro IIZUKA, Tatsuya KOGURE, Yosuke IDE, Yoshihiro NISHIYAMA, Kenji ICHINOHE, Naoki SAKATSUME, Tsuyoshi NOJIMA, Shigenobu MIYAJIMA, Hidekazu KOBAYASHI