Patents by Inventor Hiroko Ikeda

Hiroko Ikeda 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).

  • Publication number: 20240136874
    Abstract: A rotating electrical machine includes a stator and a rotor, the rotor includes a rotor core and a plurality of magnetic poles, the plurality of magnetic poles includes a plurality of magnet poles formed by permanent magnets, and a plurality of dummy poles, the magnet poles and the dummy poles are alternately disposed in both an axial direction and a circumferential direction, non-magnetic holes are provided between the magnet poles and the dummy poles that are adjacent in the axial direction, and when a length of each magnet pole in the axial direction is tm, a length of each dummy pole in the axial direction is tc, a length of each non-magnetic hole in the axial direction is ta, and a length of the rotor core in the axial direction is lc, the rotating electrical machine satisfies tm>tc and lc<(2×tm)+ta.
    Type: Application
    Filed: February 26, 2021
    Publication date: April 25, 2024
    Applicant: Mitsubishi Electric Corporation
    Inventors: Hidenori SASAKI, Kenta MOTOYOSHI, Yu HIROTANI, Hiroko IKEDA, Shohei FUJIKURA
  • Patent number: 11959197
    Abstract: A first aspect of the present invention is carbon fiber wherein the surface of a monofilament has a center line average roughness Ra of 6.0 nm or more and 13 nm or less, and the monofilament has a long diameter/short diameter ratio of 1.11 or more and 1.245 or less. A second aspect of the present invention is carbon fiber precursor acrylic fiber wherein the surface of a monofilament has a center line average roughness Ra of 18 nm or more and 27 nm or less, and the monofilament has a long diameter/short diameter ratio of 1.11 or more and 1.245 or less. The carbon fiber according to the first aspect is obtained by stabilizing and carbonizing under specific conditions the carbon fiber precursor acrylic fiber according to the second aspect.
    Type: Grant
    Filed: August 15, 2019
    Date of Patent: April 16, 2024
    Assignee: Mitsubishi Chemical Corporation
    Inventors: Naomasa Matsuyama, Yuutarou Nakamura, Norifumi Hirota, Hiroko Matsumura, Katsuhiko Ikeda, Kouki Wakabayashi, Tadashi Ootani, Akihiro Itou, Kenji Hirano, Akito Hatayama, Kenji Kaneta, Atsushi Nakajima
  • Patent number: 11901772
    Abstract: A rotor core of a rotating electrical machine has interpole bridges each disposed on an outer circumferential side with respect to a permanent magnet in a non-magnetic portion between the poles, and interpole diameter bridges each surrounded by two permanent magnets and an interpole bridge. The outer circumferential surface of each interpole bridge is formed by a first flat surface. Thus, a path of a magnetic flux passing through a magnetic gap is lengthened, so that a q-axis inductance is reduced. In addition, a width in a radial direction of each interpole bridge and a width in a circumferential direction of each interpole diameter bridge are constant, and each interpole bridge and each interpole diameter bridge are disposed so as to be perpendicular to each other to form a T shape. Thus, the concentration of stress during press-fitting of the permanent magnet into a magnet hole can be reduced.
    Type: Grant
    Filed: November 27, 2018
    Date of Patent: February 13, 2024
    Assignee: Mitsubishi Electric Corporation
    Inventors: Kodai Okazaki, Kenta Motoyoshi, Yuji Takizawa, Hiroko Ikeda, Hidenori Sasaki, Yu Hirotani, Satoru Akutsu, Masafumi Okazaki, Natsumi Sugi
  • Patent number: 11828591
    Abstract: Even using the redundant system resolver in which the magnetic interference between systems occurs, to provide an angle detection apparatus which can reduces the influence of the magnetic interference and can calculate the rotational angle with good accuracy, without performing synchronous control between systems in real time. An angle detection apparatus is provided with a resolver which has the first system windings and the second system windings in which magnetic interference occurs between systems; a first system removal processing unit that performs a second cycle component removal processing which removes component of the second cycle of the second system, to detection values of the first system winding output signals; and a first system angle calculation unit that calculates a first angle of rotor, based on the detection values of the first system winding output signals after the second cycle component removal processing.
    Type: Grant
    Filed: January 25, 2019
    Date of Patent: November 28, 2023
    Assignee: Mitsubishi Electric Corporation
    Inventors: Tatsuya Mori, Toshihiro Matsunaga, Hiroko Ikeda, Seiji Sawada, Kenta Kubo, Kenji Ikeda
  • Publication number: 20230378832
    Abstract: In an electric rotating machine according to this application, a maximum height of a permanent magnet in a rotor and a flange-part root radial thickness of the tooth portion in the stator can be set properly, so that it is possible to eliminate unbalanced magnetic saturation at flange parts of the heads of the tooth portions. This makes it possible to reduce an unbalance between torque ripples that are generated respectively by an upper-side rotor block and a lower-side rotor block when an electric power steering apparatus is driven under static steering conditions, to thereby achieve an electric rotating machine with a suppressed torque ripple. With the use of this electric rotating machine, since the torque-ripple unbalance is reduced, it is possible to achieve an electric power steering apparatus with a suppressed torque ripple.
    Type: Application
    Filed: October 27, 2020
    Publication date: November 23, 2023
    Applicant: MITSUBISHI ELECTRIC CORPORATION
    Inventors: Yu HIROTANI, Kenta MOTOYOSHI, Hiroko IKEDA, Shohei FUJIKURA
  • Publication number: 20230318488
    Abstract: If a current detection resistance (8) is connected between a lower-arm switching element (SN) and a negative-electrode-side input terminal of an inverter (6), a conduction resistance (Rp) between an output terminal and a positive-electrode-side input terminal of the inverter (6) is set to be higher than a conduction resistance (Rn) obtained by excluding the current detection resistance from a conduction resistance between the output terminal and the negative-electrode-side input terminal of the inverter (6). If the current detection resistance (8) is connected between an upper-arm switching element (SP) and the positive-electrode-side input terminal, the conduction resistance (Rn) between the output terminal and the negative-electrode-side input terminal of the inverter (6) is set to be higher than a conduction resistance (Rp) obtained by excluding the current detection resistance from the conduction resistance between the output terminal and the positive-electrode-side input terminal of the inverter (6).
    Type: Application
    Filed: July 22, 2020
    Publication date: October 5, 2023
    Applicant: Mitsubishi Electric Corporation
    Inventors: Tatsuya MORI, Hiroko IKEDA, Kenta KUBO, Yu HIROTANI
  • Patent number: 11750134
    Abstract: To provide an AC rotary machine apparatus which can determine the operation stop of the control circuit of the other system with good accuracy. An AC rotary machine apparatus, including: a resolver is provided with a first system excitation winding, first system two output windings, a second system excitation winding, and second system two output windings, in which a magnetic interference occurs between a first system and a second system; a first system control circuit that applies AC voltage with a first period to the first system excitation winding; and a second system control circuit that applies AC voltage with a second period to the second system excitation winding, wherein the first system control circuit determines whether the operation of the second system control circuit stops, based on the components of the second period extracted from the first system output signals.
    Type: Grant
    Filed: September 26, 2019
    Date of Patent: September 5, 2023
    Assignee: Mitsubishi Electric Corporation
    Inventors: Tatsuya Mori, Hiroko Ikeda, Toshihiro Matsunaga, Kenji Ikeda, Kenta Kubo
  • Patent number: 11736049
    Abstract: To provide a motor controller which can suppress occurrence of a torque difference between systems, even if a DC voltage difference occurs between systems, in the case where each system is provided with a DC power source. A motor controller is provided with a first controller that controls so that the first q-axis current detection value approaches the second q-axis current detection value or the second q-axis current command value obtained from the second controller, when determining that the first DC voltage is higher than the second DC voltage; and a second controller that controls so that the second q-axis current detection value approaches the first q-axis current detection value or the first q-axis current command value obtained from the first controller, when determining that the second DC voltage is higher than the first DC voltage.
    Type: Grant
    Filed: November 27, 2019
    Date of Patent: August 22, 2023
    Assignee: Mitsubishi Electric Corporation
    Inventors: Jun Kitagawa, Tatsuya Mori, Hiroko Ikeda, Haruna Koyama, Kenta Kubo
  • Publication number: 20230249742
    Abstract: To provide a controller for a rotary electric machine and an electric power steering apparatus which can suppress the error increase of the rotational angle due to the high frequency noise component included in the current detection value, while reducing the AC component error included in the sensor detection value of rotational angle, at high rotational speed. A controller for a rotary electric machine estimates an estimation actual angle deviation; calculates a detection angle deviation; calculates a control angle deviation by dividing internally between the estimation actual angle deviation and the detection angle deviation; calculates a rotational angle for control by performing feedback control so that the control angle deviation approaches 0; and makes the ratio of the estimation actual angle deviation higher than the ratio of the detection angle deviation, when the rotational speed is higher than a speed threshold value.
    Type: Application
    Filed: October 5, 2020
    Publication date: August 10, 2023
    Applicant: Mitsubishi Electric Corporation
    Inventors: Tatsuya MORI, Hiroko IKEDA, Kenta KUBO
  • Publication number: 20230208225
    Abstract: A rotating electric machine includes a stator and a rotor. The rotor includes a rotor core and a plurality of permanent magnets. The rotor core includes a plurality of core portions. The rotor core includes an annular portion and a plurality of coupling portions. Each of the plurality of coupling portions couples the annular portion and a first core portion of each of the plurality of core portions to each other. Each of the plurality of coupling portions has at least one coupling path. A sum of a width of a portion having the smallest width in at least one coupling path is smaller than a length of a joining boundary between the annular portion and each of the plurality of coupling portions.
    Type: Application
    Filed: August 20, 2020
    Publication date: June 29, 2023
    Applicant: Mitsubishi Electric Corporation
    Inventors: Hidenori SASAKI, Kenta MOTOYOSHI, Shohei FUJIKURA, Hiroko IKEDA, Koji KAWAMURA
  • Publication number: 20230194313
    Abstract: To provide an angle detection apparatus which can reduce the error of the angle which is caused by the eccentricity, by performing the reduction processing about smallest possible number of frequency bands and the lowest possible order of frequency band. An angle detection apparatus performs a first-order component reduction processing which reduces a first-order component which is a component of one rotation period in a mechanical angle of the rotor, to each of the first system two output signals; and calculates a first angle (?1) of the rotor, based on the first system two output signals to which the first-order component reduction processing was performed.
    Type: Application
    Filed: February 6, 2020
    Publication date: June 22, 2023
    Applicant: Mitsubishi Electric Corporation
    Inventors: Tatsuya MORI, Hiroko IKEDA, Toshihiro MATSUNAGA, Kenji IKEDA, Kenta KUBO
  • Publication number: 20230155528
    Abstract: In an electric motor control device which controls rotation of an AC electric motor having two sets of three-phase windings and provided with a resolver having two systems by calculating voltage command values on dq axes, dq conversion of currents of first three-phase windings is performed using a first angle calculated from output of the first system of the resolver, and dq conversion of currents of second three-phase windings is performed using a second angle calculated from output of the second system of the resolver. With both d-axis current command values set at the same value, respective voltage command values on dq axes are calculated and respectively converted into voltage command values for voltage application to the first three-phase windings, using the first angle, and converted into voltage command values for voltage application to the second three-phase windings, using the second angle.
    Type: Application
    Filed: May 19, 2020
    Publication date: May 18, 2023
    Applicant: Mitsubishi Electric Corporation
    Inventors: Masahiko ORII, Tatsuya MORI, Hiroko IKEDA, Toshihiro MATSUNAGA, Kenji IKEDA, Kenta KUBO
  • Publication number: 20230125647
    Abstract: A resolver body including a rotor having Nx (Nx is a natural number) salient poles, a stator facing the rotor and having Ns (Ns is an integer equal to or larger than 3) teeth arranged in a circumferential direction, and an excitation winding and two phases of output windings wound on each tooth; and an excitation circuit configured to apply voltage to the excitation winding. The excitation winding and the two phases of output windings wound on each of Nsm (Nsm is an integer equal to or larger than 2) teeth among the Ns teeth are set to be of a main system. The excitation winding and the two phases of output windings wound on each of Ns-Nsm teeth are set to be of a sub-system. The number Nsm of the teeth corresponding to the main system is larger than the number Ns-Nsm of the teeth corresponding to the sub-system.
    Type: Application
    Filed: April 9, 2020
    Publication date: April 27, 2023
    Applicant: Mitsubishi Electric Corporation
    Inventors: Hiroko IKEDA, Shohei FUJIKURA, Tatsuya MORI, Kenji IKEDA, Kenta KUBO, Toshihiro MATSUNAGA
  • Publication number: 20230112554
    Abstract: To provide an abnormality detection apparatus for resolver which can determine the abnormality of at least the first system, even if the period of the excitation AC voltage of the first system and the period of the excitation AC voltage of the second system are different periods, and the magnetic interference between systems occurs. An abnormality detection apparatus for resolver applies an AC voltage of a first period to a first system excitation winding; applies an AC voltage of a second period different from the first period to a second system excitation winding; calculates DC values of first system two output signals by performing a DC extraction processing; and determines abnormality of first system based on whether or not the DC values of first system two output signals are within a normal range.
    Type: Application
    Filed: February 26, 2020
    Publication date: April 13, 2023
    Applicant: Mitsubishi Electric Corporation
    Inventors: Tatsuya MORI, Hiroko IKEDA, Toshihiro MATSUNAGA, Kenji IKEDA, Kenta KUBO
  • Publication number: 20230078128
    Abstract: To solve a problem that the accuracy of angle detection deteriorates owing to noise voltage generated by eccentricity or variation in shape among rotors according to the number of magnetic poles of a rotor core of a multiple-system rotation sensor, the number S of magnetic poles of a stator core is, with the number R of the magnetic poles of the rotor core and the number N (N is a natural number equal to or larger than 2) of systems for stator windings, in a relationship of S=nRN (n is a natural number), system windings of each system are wound so as to be divided for every R magnetic poles among the S magnetic poles of the stator core, and a winding arrangement of the system windings of each system is made so as to achieve R-times rotational symmetry about a rotor rotation axis.
    Type: Application
    Filed: April 9, 2020
    Publication date: March 16, 2023
    Applicant: Mitsubishi Electric Corporation
    Inventors: Shohei FUJIKURA, Hiroko IKEDA, Tatsuya MORI, Kenji IKEDA, Kenta KUBO, Toshihiro MATSUNAGA
  • Publication number: 20230055461
    Abstract: To provide an abnormality detection apparatus for resolver which can determine the abnormality of at least the first system, even if the period of the excitation AC voltage of the first system and the period of the excitation AC voltage of the second system are different periods, and the magnetic interference between systems occurs. An abnormality detection apparatus for resolver applies an AC voltage of a first period to a first system excitation winding; applies an AC voltage of a second period different from the first period to a second system excitation winding; calculates a first system square sum which is a sum of square values of the detection values of output signals of first system two output windings after the second period component reduction processing: and determines abnormality of first system based on whether or not the first system square sum is within a normal range of first system.
    Type: Application
    Filed: February 26, 2020
    Publication date: February 23, 2023
    Applicant: Mitsubishi Electric Corporation
    Inventors: Tatsuya MORI, Hiroko IKEDA, Toshihiro MATSUNAGA, Kenji IKEDA, Kenta KUBO
  • Publication number: 20230013379
    Abstract: Provided is a resolver capable of increasing an accuracy of a detected angle of the resolver. The resolver includes: a stator; and a rotor, wherein the rotor includes a plurality of salient poles; wherein the stator includes: a stator core having a plurality of teeth, and a plurality of winding groups each of which is provided on each of the plurality of teeth, wherein the winding groups are divided into two systems, wherein the numbers of turns of the excitation windings are distributed in a form of a sine wave of Ne-th spatial order, wherein each of the numbers of turns of a first output windings and the numbers of turns of a second output windings are distributed in a form of a sine wave of |Ne±Nx|-th spatial order, and wherein the following expressions are satisfied, Nout1=N1 cos{|Ne±Nx|(i?1)/Ns×2?+?}, Nout2=N1 cos{|Ne±Nx|(i?1)/Ns×2?+?}, and 90(deg)<|???|<140(deg).
    Type: Application
    Filed: January 17, 2020
    Publication date: January 19, 2023
    Applicant: Mitsubishi Electric Corporation
    Inventors: Hiroko IKEDA, Tatsuya MORI, Toshihiro MATSUNAGA, Kenji IKEDA, Kenta KUBO
  • Publication number: 20220393627
    Abstract: To provide a motor controller which can suppress occurrence of a torque difference between systems, even if a DC voltage difference occurs between systems, in the case where each system is provided with a DC power source. A motor controller is provided with a first controller that controls so that the first q-axis current detection value approaches the second q-axis current detection value or the second q-axis current command value obtained from the second controller, when determining that the first DC voltage is higher than the second DC voltage; and a second controller that controls so that the second q-axis current detection value approaches the first q-axis current detection value or the first q-axis current command value obtained from the first controller, when determining that the second DC voltage is higher than the first DC voltage.
    Type: Application
    Filed: November 27, 2019
    Publication date: December 8, 2022
    Applicant: Mitsubishi Electric Corporation
    Inventors: Jun KITAGAWA, Tatsuya MORI, Hiroko IKEDA, Haruna KOYAMA, Kenta KUBO
  • Patent number: 11512977
    Abstract: A redundant resolver is configured of a stator and a rotor that form a pair, wherein the rotor is a rotor with a shaft angle multiplier of Nx having Nx (Nx is a natural number) salient poles, the stator is such that n teeth T1 to Tn, where n is a natural number, are disposed sequentially in a circumferential direction, configuring M systems by being divided into M in the circumferential direction, and having an angle of 360/M degrees when angles of the teeth configuring one system are totaled, a one-phase excitation winding and a two-phase output winding are wound around each of the teeth T1 to Tn, excitation signals of the same frequency are applied by differing excitation circuits to the respective excitation windings, an output order per system is Nout (Nout is a natural number), and an abnormality is detected based on output signals of the M systems.
    Type: Grant
    Filed: December 21, 2017
    Date of Patent: November 29, 2022
    Assignee: Mitsubishi Electric Cornoration
    Inventors: Hiroko Ikeda, Yuji Takizawa, Kazumasa Ito, Shinichi Yamaguchi, Toshihiro Matsunaga, Yosuke Sugino
  • Publication number: 20220376641
    Abstract: To provide an AC rotary machine apparatus which can determine the operation stop of the control circuit of the other system with good accuracy. An AC rotary machine apparatus, including: a resolver is provided with a first system excitation winding, first system two output windings, a second system excitation winding, and second system two output windings, in which a magnetic interference occurs between a first system and a second system; a first system control circuit that applies AC voltage with a first period to the first system excitation winding; and a second system control circuit that applies AC voltage with a second period to the second system excitation winding, wherein the first system control circuit determines whether the operation of the second system control circuit stops, based on the components of the second period extracted from the first system output signals.
    Type: Application
    Filed: September 26, 2019
    Publication date: November 24, 2022
    Applicant: Mitsubishi Electric Corporation
    Inventors: Tatsuya MORI, Hiroko IKEDA, Toshihiro MATSUNAGA, Kenji IKEDA, Kenta KUBO