Patents by Inventor Hirofumi Okumura

Hirofumi Okumura has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 9915710
    Abstract: A magnetic sensor is provided in which in a case where magnetization amounts of the first ferromagnetic layer and the second ferromagnetic layer in the first magnetic sensor element are respectively set to be Mst11 and Mst12 and magnetization amounts of the first ferromagnetic layer and the second ferromagnetic layer in the second magnetic sensor element are respectively set to be Mst21 and Mst22, in a case of Mst11>Mst12, a relationship of Mst21>Mst22 is satisfied, and in a case of Mst11<Mst12, a relationship of Mst21<Mst22 is satisfied.
    Type: Grant
    Filed: April 1, 2016
    Date of Patent: March 13, 2018
    Assignee: ALPS ELECTRIC CO., LTD.
    Inventors: Fumihito Koike, Hirofumi Okumura, Eiji Shinohara, Kazuhiro Shigeta, Taku Saito
  • Publication number: 20160341802
    Abstract: A magnetic sensor includes: a first magnetic detection element group and a second magnetic detection element group each of which including a plurality of self-pinned magnetoresistive effect elements; and a first control unit and a second control unit configured to respectively process detection signals detected from a magnetic field by the magnetoresistive effect elements of the first magnetic detection element group and the second magnetic detection element group, in which pinned magnetization directions of at least two magnetoresistive effect elements in the first magnetic detection element group and the second magnetic detection element group are different from each other, and the plurality of magnetoresistive effect elements of the first magnetic detection element group and the plurality of magnetoresistive effect elements of the second magnetic detection element group are arranged so that the magnetization directions thereof are symmetrical.
    Type: Application
    Filed: May 2, 2016
    Publication date: November 24, 2016
    Inventors: Fumihito KOIKE, Ichiro TOKUNAGA, Hirofumi OKUMURA, Yukiko YASUDA
  • Publication number: 20160313411
    Abstract: A magnetic sensor is provided in which in a case where magnetization amounts of the first ferromagnetic layer and the second ferromagnetic layer in the first magnetic sensor element are respectively set to be Mst11 and Mst12 and magnetization amounts of the first ferromagnetic layer and the second ferromagnetic layer in the second magnetic sensor element are respectively set to be Mst21 and Mst22, in a case of Mst11>Mst12, a relationship of Mst21>Mst22 is satisfied, and in a case of Mst11<Mst12, a relationship of Mst21<Mst22 is satisfied.
    Type: Application
    Filed: April 1, 2016
    Publication date: October 27, 2016
    Inventors: Fumihito KOIKE, Hirofumi OKUMURA, Eiji SHINOHARA, Kazuhiro SHIGETA, Taku SAITO
  • Publication number: 20120191406
    Abstract: In an angular speed detection apparatus according to the present embodiment, in a positive counter, a first counter value P is obtained by adding 3 when an average angular speed “ASMAV (deg/s)” calculated at each “time” is higher than or equal to, for example, 3000 (deg/s) and subtracting 1 when the average angular speed is lower than 3000. In a negative counter, a second counter value M is obtained by adding 3 when the average angular speed “ASMAV (deg/s)” is lower than or equal to ?3000 (deg/s) and subtracting 1 when the average angular speed is higher than ?3000. When the first counter value or the second counter value has exceeded a predetermined error threshold (for example, 20), it is determined that an error has occurred.
    Type: Application
    Filed: January 24, 2012
    Publication date: July 26, 2012
    Applicant: Alps Electric Co., Ltd.
    Inventors: Hirofumi OKUMURA, Tsukasa MIZUSAWA
  • Patent number: 7521924
    Abstract: An object of the present invention is to provide a member position detecting apparatus having a high degree of freedom for design and layout of a seat rail, capable of suppressing accumulation of dust and eliminating influence of an external magnetic field. A member position detecting apparatus 1 has a function of detecting whether a metallic seat rail (a moving member) 3 guided by a metallic stationary rail 2 has reached a front end position (a predetermined position) P on the stationary rail 2. The openings of the stationary rail 2 and the seat rail 3 face each other and the end portions thereof are folded and engaged with each other. The stationary rail 2 is disposed on the floor of a vehicle, and a planar magnet 5 is provided at a front end portion thereof. The seat rail 3 is fixed on a lower portion of the vehicle seat, and a magnetic sensor 7 is provided to face the magnet 5 at the front end portion of the seat rail.
    Type: Grant
    Filed: April 19, 2004
    Date of Patent: April 21, 2009
    Assignee: Alps Electric Co., Ltd.
    Inventors: Hirofumi Okumura, Ichiro Tokunaga
  • Patent number: 7064537
    Abstract: First and second GMR devices formed in a first block and fifth and sixth GMR devices formed in a third block are disposed in a symmetrical manner as to a point of origin. The first and fifth GMR devices, and the second and sixth GMR devices are disposed in a symmetrical manner as to the point of origin, and accordingly the intensity and direction of an external magnetic field applied from a rotating magnet is the equal between the first and fifth GMR devices, and also equal between the second and sixth GMR devices. Thus, combining the first, fifth, second, and sixth GMR devices to form a Wheatstone bridge circuit enables detection precision of rotation angles to be improved.
    Type: Grant
    Filed: September 26, 2003
    Date of Patent: June 20, 2006
    Assignee: Alps Electric Co., Ltd.
    Inventors: Yoshihiro Sudo, Hirofumi Okumura
  • Patent number: 7045998
    Abstract: A steering output part is fixed with a worm wheel for power assist. By a spur gear formed on the worm wheel, an input gear of a detecting unit is rotated with a speed increase. Within the detecting unit, provided is a speed-reducing mechanism for speed-reducing the rotation of the detecting shaft. By this speed reduction, a detection rotating member provided in a case rotates at an angle of 1:1 to the rotation of the steering output part, a rotation angle of which is detected by a detecting element.
    Type: Grant
    Filed: April 24, 2003
    Date of Patent: May 16, 2006
    Assignees: ALPS Electric Co., Ltd, NSK Ltd., NSK Steering Systems Co., Ltd
    Inventor: Hirofumi Okumura
  • Patent number: 6900713
    Abstract: A magnetic switch using magnetoresistive elements having respective free layers whose magnetization directions are varied by an external magnetic field. The magnetic switch also has a first magnet and a second magnet that produce respective magnetic fields that serve as the external magnetic field and are different from each other in strength and opposite to each other in direction, and a magnetic shield member whose relative position with respect to the first magnet and the second magnet varies. The magnetic shield member moves between a first position with which both of the magnetic fields of the first magnet and the second magnet act on the magnetoresistive elements to magnetize their free layers in a first direction and a second position with which only one of the magnetic fields of the first magnet and the second magnet acts on the magnetoresistive elements to magnetize their free layers in a second direction that is opposite to the first direction.
    Type: Grant
    Filed: August 9, 2002
    Date of Patent: May 31, 2005
    Assignee: Alps Electric Co., Ltd.
    Inventors: Masao Kasashima, Ichiro Tokunaga, Hirofumi Okumura, Seiji Kikuchi
  • Patent number: 6809513
    Abstract: A rotary position sensor includes a cylindrical housing having a partition wall which divides the interior of the housing into a first storing space and a second storing space. The first storing space stores a rotating mechanism and is closed with a first cover in such a manner that a shaft portion of a rotating member projects outside, and the second storing space stores an electrical circuit component and is closed with a second cover. A magnet included in the rotating mechanism is disposed at a position close to the partition wall, and a giant magnetoresistive element included in the electrical circuit component is disposed in a recess formed in the partition wall. Thus, the rotating mechanism and the electrical circuit component are completely separated from each other by the partition wall, so that a complex sealing process is not necessary and the detection accuracy can be increased.
    Type: Grant
    Filed: March 7, 2003
    Date of Patent: October 26, 2004
    Assignee: Alps Electric Co., Ltd.
    Inventors: Kyuichiro Terui, Hirofumi Okumura
  • Publication number: 20040196029
    Abstract: An object of the present invention is to provide a member position detecting apparatus having a high degree of freedom for design and layout of a seat rail, capable of suppressing accumulation of dust and eliminating influence of an external magnetic field. A member position detecting apparatus 1 has a function of detecting whether a metallic seat rail (a moving member) 3 guided by a metallic stationary rail 2 has reached a front end position (a predetermined position) P on the stationary rail 2. The openings of the stationary rail 2 and the seat rail 3 face each other and the end portions thereof are folded and engaged with each other. The stationary rail 2 is disposed on the floor of a vehicle, and a planar magnet 5 is provided at a front end portion thereof. The seat rail 3 is fixed on a lower portion of the vehicle seat, and a magnetic sensor 7 is provided to face the magnet 5 at the front end portion of the seat rail.
    Type: Application
    Filed: April 19, 2004
    Publication date: October 7, 2004
    Applicant: ALPS ELECTRIC CO., LTD.
    Inventors: Hirofumi Okumura, Ichiro Tokunaga
  • Patent number: 6784774
    Abstract: A magnetic switch hardly affected by an external magnetic field even if a cheap magnet is used and capable of performing magnetic detection for a long period of time is provided. A first magnetic path L1 and a second magnetic path L2 in which a stationary rail 13 and a movable rail 14 lead magnetic fluxes are formed in a non-shielding state where magnetism shielding 18 is not interposed in a gap G between a magnet M and a Hall element H to secure the number of magnetic fluxes that pass through the Hall element H. Therefore, it is not necessary to use a costly rare earth magnet having a large number of generated magnetic fluxes. In n shielding state where the magnetism shielding 18 is interposed in the gap G, the first magnetic path L1 is shielded. As a result, the number of magnetic fluxes that pass through the Hall element H is almost zero.
    Type: Grant
    Filed: February 18, 2004
    Date of Patent: August 31, 2004
    Assignee: ALPS Electric Co., Ltd.
    Inventor: Hirofumi Okumura
  • Publication number: 20040164826
    Abstract: A magnetic switch hardly affected by an external magnetic field even if a cheap magnet is used and capable of performing magnetic detection for a long period of time is provided. A first magnetic path L1 and a second magnetic path L2 in which a stationary rail 13 and a movable rail 14 lead magnetic fluxes are formed in a non-shielding state where magnetism shielding means 18 is not interposed in a gap G between a magnet M and a Hall element H to secure the number of magnetic fluxes that pass through the Hall element H. Therefore, it is not necessary to use a costly rare earth magnet having a large number of generated magnetic fluxes. In n shielding state where the magnetism shielding means 18 is interposed in the gap G, the first magnetic path L1 is shielded. As a result, the number of magnetic fluxes that pass through the Hall element H is almost zero.
    Type: Application
    Filed: February 18, 2004
    Publication date: August 26, 2004
    Applicant: ALPS ELECTRIC CO., LTD.
    Inventor: Hirofumi Okumura
  • Patent number: 6720762
    Abstract: A rotation-angle detecting device includes a rotor, a first output mechanism for outputting a first detection signal in response to the rotation of the rotor, and a second output mechanism for outputting a second detection signal in response to the rotation of the rotor. The first output mechanism includes a first output gear meshed with a first transmission gear of the rotor and having an axis in parallel with the axis of the rotor, and a first output section for outputting the first detection signal in response to the rotation of the first output gear. The second output mechanism includes a second output gear meshed with a second transmission gear of the rotor and having an axis in parallel with the axis of the rotor, and a second output section for outputting the second detection signal in response to the rotation of the second output gear.
    Type: Grant
    Filed: February 27, 2003
    Date of Patent: April 13, 2004
    Assignee: Alps Electric Co., Ltd.
    Inventor: Hirofumi Okumura
  • Publication number: 20040066186
    Abstract: First and second GMR devices formed in a first block and fifth and sixth GMR devices formed in a third block are disposed in a symmetrical manner as to a point of origin. The first and fifth GMR devices, and the second and sixth GMR devices are disposed in a symmetrical manner as to the point of origin, and accordingly the intensity and direction of an external magnetic field applied from a rotating magnet is the equal between the first and fifth GMR devices, and also equal between the second and sixth GMR devices. Thus, combining the first, fifth, second, and sixth GMR devices to form a Wheatstone bridge circuit enables detection precision of rotation angles to be improved.
    Type: Application
    Filed: September 26, 2003
    Publication date: April 8, 2004
    Applicant: ALPS ELECTRIC CO., LTD.
    Inventors: Yoshihiro Sudo, Hirofumi Okumura
  • Patent number: 6687647
    Abstract: The absolute angle of the rotation angle is detected on the basis of a first detection signal including sawtooth continuous pulses and a second detection signal that rises stepwise. The second detection signal includes a plurality of flat portions and a plurality of gradually rising portions that link the flat portions, corresponding to the pulses of the first detection signal. Each gradually rising portion corresponds to the sharply falling portion of the first detection signal. When the value of the second detection signal is included in a flat portion, the absolute angle is found based on the first and second detection signals, and, when the value of the second detection signal is included in a gradually rising portion, the absolute angle is found based on the first detection signal in conjunction with the second detection signal corresponding to a flat portion preceding or following the gradually rising region.
    Type: Grant
    Filed: February 27, 2003
    Date of Patent: February 3, 2004
    Assignee: Alps Electric Co., Ltd.
    Inventor: Hirofumi Okumura
  • Publication number: 20030227369
    Abstract: A rotary sensor with a prolonged service life ensures stable electrical conduction between an intermediate terminal and an electrode even if the components making up the rotary sensor repeatedly expand and contract due to high and low temperatures. In the rotary sensor, an output detection member is constructed of an insulating board having an electrode on its surface, a retaining portion being formed on the insulating board. The intermediate terminal is made of a metal material, and has a pair of mounting portions provided on both ends thereof and a first contact portion and a second contact portion provided between the pair of mounting portions. The intermediate terminal is secured to the retaining portion of the insulating board by the pair of mounting portions such that it sandwiches the insulating board lengthwise. The first contact portion is in resilient contact with the internal pin and the second contact portion is in resilient contact with the electrode.
    Type: Application
    Filed: May 19, 2003
    Publication date: December 11, 2003
    Applicant: ALPS ELECTRIC CO., LTD.
    Inventors: Kyuichiro Terui, Hirofumi Okumura, Moritoshi Nakamura
  • Publication number: 20030214284
    Abstract: A steering output part is fixed with a worm wheel for power assist. By a spur gear formed on the worm wheel, an input gear of a detecting unit is rotated with a speed increase. Within the detecting unit, provided is a speed-reducing mechanism for speed-reducing the rotation of the detecting shaft. By this speed reduction, a detection rotating member provided in a case rotates at an angle of 1:1 to the rotation of the steering output part, a rotation angle of which is detected by a detecting element.
    Type: Application
    Filed: April 24, 2003
    Publication date: November 20, 2003
    Applicant: ALPS ELECTRIC CO., LTD.
    Inventor: Hirofumi Okumura
  • Publication number: 20030173954
    Abstract: A rotary position sensor includes a cylindrical housing having a partition wall which divides the interior of the housing into a first storing space and a second storing space. The first storing space stores a rotating mechanism and is closed with a first cover in such a manner that a shaft portion of a rotating member projects outside, and the second storing space stores an electrical circuit component and is closed with a second cover. A magnet included in the rotating mechanism is disposed at a position close to the partition wall, and a giant magnetoresistive element included in the electrical circuit component is disposed in a recess formed in the partition wall. Thus, the rotating mechanism and the electrical circuit component are completely separated from each other by the partition wall, so that a complex sealing process is not necessary and the detection accuracy can be increased.
    Type: Application
    Filed: March 7, 2003
    Publication date: September 18, 2003
    Applicant: ALPS ELECTRIC CO., LTD.
    Inventors: Kyuichiro Terui, Hirofumi Okumura
  • Publication number: 20030169034
    Abstract: A rotation-angle detecting device includes a rotor, a first output mechanism for outputting a first detection signal in response to the rotation of the rotor, and a second output mechanism for outputting a second detection signal in response to the rotation of the rotor. The first output mechanism includes a first output gear meshed with a first transmission gear of the rotor and having an axis in parallel with the axis of the rotor, and a first output section for outputting the first detection signal in response to the rotation of the first output gear. The second output mechanism includes a second output gear meshed with a second transmission gear of the rotor and having an axis in parallel with the axis of the rotor, and a second output section for outputting the second detection signal in response to the rotation of the second output gear.
    Type: Application
    Filed: February 27, 2003
    Publication date: September 11, 2003
    Applicant: ALPS ELECTRIC CO., LTD.
    Inventor: Hirofumi Okumura
  • Publication number: 20030167858
    Abstract: A rotary sensor comprising a rotor having a shaft portion, a casing supporting the rotor, an angle detecting member operated by the rotor, and a cover member for closing an open end portion of the casing, the shaft portion of the rotor being formed from a synthetic resin material, the cover member being formed from a metallic material, one of the shaft portion and the cover member being provided with a projection, the other of the shaft portion and the cover member being provided with a recess, and the projection being arranged in the recess.
    Type: Application
    Filed: March 3, 2003
    Publication date: September 11, 2003
    Applicant: ALPS ELECTRIC CO., LTD.
    Inventors: Kyuichiro Terui, Hirofumi Okumura, Moritoshi Nakamura