Patents by Inventor Masashi Miwa

Masashi Miwa 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: 11971540
    Abstract: An optical system (LS) includes lenses (L22,L23) satisfying the following conditional expressions, ndLZ+(0.01425×?dLZ)<2.12, and ?dLZ<35.0, where ndLZ: a refractive index of the lens with reference to d-line, and ?dLZ: Abbe number of the lens with reference to d-line.
    Type: Grant
    Filed: December 15, 2017
    Date of Patent: April 30, 2024
    Assignee: Nikon Corporation
    Inventors: Masashi Yamashita, Tomoki Ito, Hiroshi Yabumoto, Hiroshi Yamamoto, Satoshi Miwa, Keisuke Tsubonoya, Ayumu Makida, Takeru Uehara
  • Publication number: 20240025345
    Abstract: A vehicle step device includes: a step portion that is attached to a side of a vehicle and is deployed from a retracted position to a getting-on/off position when an occupant gets on and off the vehicle; and a drive unit configured to drive the step portion between the retracted position and the getting-on/off position. The drive unit deploys the step portion to a traveling position located outward of the retracted position in a vehicle width direction when a predetermined condition is satisfied in a vehicle traveling state.
    Type: Application
    Filed: July 13, 2023
    Publication date: January 25, 2024
    Applicant: AISIN CORPORATION
    Inventors: Kimihiro SEKINE, Masashi MIWA, Ryota TACHI
  • Publication number: 20230391263
    Abstract: A step apparatus for a vehicle includes: an arm rotatably provided on a base; and a step supported by the arm and movably provided, by rotation of the arm, between a deployed position and a stowed position located at an inner side of a vehicle width direction with respect to the deployed position. The step apparatus for a vehicle is in, by the rotation of the arm, a deployed state in which the step is disposed at the deployed position and the step is to be used or a stowed state in which the step is disposed at the stowed position and stowed under a vehicle body. At least one of the step and the base includes a contact portion to be brought into contact with the other one. The contact portion is provided to contact the other one of the step and the base when the step is disposed at the stowed position.
    Type: Application
    Filed: November 9, 2021
    Publication date: December 7, 2023
    Applicant: AISIN CORPORATION
    Inventors: Masashi MIWA, Atsushi MURAMATSU, Natsuki ITO, Takahisa KOBAYASHI, Norio KATO, Kimihiro KINOSHITA
  • Publication number: 20230391264
    Abstract: A step apparatus for a vehicle includes a base attached to an outer side of a vehicle body, an arm rotatably provided on the base, and a step supported by the arm and movable with respect to the base. The step apparatus for a vehicle is in, by rotation of the arm, a deployed state in which the step is to be used or a stowed state in which the step is stowed under the vehicle body. A first rotation axis of a base end of the arm and a second rotation axis of a tip end of the arm are inclined upward toward an outer side of a vehicle width direction in an attached state in which the step apparatus for a vehicle is attached to the vehicle body.
    Type: Application
    Filed: November 9, 2021
    Publication date: December 7, 2023
    Applicant: AISIN CORPORATION
    Inventors: Masashi MIWA, Atsushi MURAMATSU, Natsuki ITO, Takahisa KOBAYASHI, Norio KATO, Kimihiro KINOSHITA
  • Patent number: 11742119
    Abstract: Provided is a permanent magnet including a rare-earth element R (such as Nd), a transition metal element T (such as Fe), B, Zr, and Cu. The permanent magnet contains a plurality of main phase grains including Nd, T, and B, and grain boundary multiple junctions, the one grain boundary multiple junction is a grain boundary surrounded by three or more of the main phase grains, one of the grain boundary multiple junctions contains a ZrB2 crystal and an R—Cu-rich phase including R and Cu, Fe is contained in the ZrB2 crystal, a total concentration of Nd and Pr in the one grain boundary multiple junction containing both the ZrB2 crystal and the R—Cu-rich phase is higher than a total concentration of Nd and Pr in the main phase grain, a concentration of Cu in the one grain boundary multiple junction containing both the ZrB2 crystal and the R—Cu-rich phase is higher than a concentration of Cu in the main phase grain, and a unit of the concentration of each of Nd, Pr, and Cu is atomic %.
    Type: Grant
    Filed: March 16, 2021
    Date of Patent: August 29, 2023
    Assignee: TDK Corporation
    Inventors: Masashi Miwa, Yoshitomo Tanaka, Koji Miura, Taeko Tsubokura
  • Patent number: 11661769
    Abstract: To provide an emergency release device of a lock system capable of opening a trunk lid using an emergency release lever, the emergency release lever is manipulatable between a first position for placing a pawl in an engagement position and a second position for placing the pawl in a non-engagement position from the inner side of the trunk and is biased toward the first position. An anti-return mechanism prevents the emergency release lever from returning from the second position to the first position when the emergency release lever is manipulated from the first position to the second position.
    Type: Grant
    Filed: January 28, 2019
    Date of Patent: May 30, 2023
    Assignee: AISIN CORPORATION
    Inventor: Masashi Miwa
  • Patent number: 11657934
    Abstract: An R-T-B based permanent magnet, excellent in magnetic properties relatively reducing amount of heavy rare earth element used, wherein R represents rare earth element, T iron group element and B boron, includes main phase grains including R2T14B crystal phase and grain boundaries between main phase grains. Grain boundaries include R—O—C—N concentrated parts where concentrations of R, O, C and N are all higher than in main phase grains. O/R(S)>O/R(C) wherein O/R(S) represents O/R ratio (atomic ratio) in R—O—C—N concentrated parts in a surface of an R-T-B based permanent magnet and O/R(C) represents O/R ratio (atomic ratio) in R—O—C—N concentrated parts in a center of an R-T-B based permanent magnet. A heavy rare earth element RH is in a surface of an R-T-B based permanent magnet as R. R—O—C—N concentrated parts in a surface of an R-T-B based permanent magnet have RH/R ratio (atomic ratio) of 0.2 or less.
    Type: Grant
    Filed: March 28, 2019
    Date of Patent: May 23, 2023
    Assignee: TDK CORPORATION
    Inventors: Yuki Nagamine, Masashi Miwa, Yoshinori Fujikawa
  • Patent number: 11636962
    Abstract: Provided is a permanent magnet including a rare-earth element R, a transition metal element T, B, Zr, and Cu. The permanent magnet contains main phase grains including Nd, T, and B, and grain boundary multiple junctions, the grain boundary multiple junction is a grain boundary surrounded by three or more of the main phase grains, one of the grain boundary multiple junctions contains a ZrB2 crystal and an R—Cu-rich phase, a concentration of B in the grain boundary multiple junction containing both the ZrB2 crystal and the R—Cu-rich phase is from 5 to 20 atomic %, a concentration of Cu in the grain boundary multiple junction containing both the ZrB2 crystal and the R—Cu-rich phase is from 5 to 25 atomic %, and a surface layer part of the main phase grain includes at least one kind of heavy rare-earth element among Tb and Dy.
    Type: Grant
    Filed: March 16, 2021
    Date of Patent: April 25, 2023
    Assignee: TDK Corporation
    Inventors: Masashi Miwa, Koji Miura, Taeko Tsubokura
  • Patent number: 11410804
    Abstract: A permanent magnet 2 includes Nd, Fe, and B, the permanent magnet 2 contains a plurality of main phase grains; and grain boundaries positioned between the main phase grains, the main phase grains include Nd, Fe, and B, at least a portion of the grain boundaries contains an R?—O—C phase, the R?—O—C phase includes a rare earth element R?, O, and C, the concentration of each of R?, O, and C in the R?—O—C phase is higher compared to the main phase grains, the permanent magnet 2 comprises a surface layer portion 21 and a central portion 22, the surface layer portion 21 is positioned on the surface side of the permanent magnet 2, the central portion 22 is positioned on the inner side of the permanent magnet 2, the proportion of the area of the R?—O—C phase occupying in a cross-section of the surface layer portion 21 is S1 %, the proportion of the area of the R?—O—C phase occupying in a cross-section of the central portion 22 is S2%, and S1 is higher than S2.
    Type: Grant
    Filed: March 14, 2020
    Date of Patent: August 9, 2022
    Assignee: TDK Corporation
    Inventor: Masashi Miwa
  • Publication number: 20210407714
    Abstract: To provide an R-T-B based permanent magnet having a high residual magnetic flux density Br at room temperature and a high coercivity HcJ at high temperature. In the R-T-B based permanent magnet, R is a rare earth element, T is an iron group element, and B is boron, and the R-T-B based permanent magnet includes a light rare earth element and a heavy rare earth element as R. The R-T-B based permanent magnet further includes Al, Ga, and Zr. With respect to 100 mass % of the R-T-B based permanent magnet, a total content of R is 28.50 mass % to 30.25 mass % (not including 28.50 mass %), B content is 0.93 mass % to 0.98 mass %, Al content is 0.03 mass % to 0.19 mass %, Ga content is 0.03 mass % to 0.15 mass %, and Zr content is 0.30 mass % to 0.50 mass %.
    Type: Application
    Filed: June 23, 2021
    Publication date: December 30, 2021
    Applicant: TDK CORPORATION
    Inventors: Koji MIURA, Masashi MIWA
  • Patent number: 11152142
    Abstract: An R-T-B based permanent magnet excellent in magnetic properties relatively reduces the amount of a heavy rare earth element used. An R-T-B based permanent magnet, wherein R represents a rare earth element, T an iron group element and B boron, includes main phase grains including an R2T14B crystal phase and grain boundaries formed between main phase grains. Grain boundaries include R—O—C—N concentrated parts where concentrations of R, O, C and N are all higher than those in main phase grains. C/R(S)>C/R(C) is satisfied in which C/R(S) represents a C/R ratio (atomic ratio) in R—O—C—N concentrated parts present in a surface of a R-T-B based permanent magnet and C/R(C) represents a C/R ratio (atomic ratio) in the R—O—C—N concentrated parts present in the center of a R-T-B based permanent magnet, and a heavy rare earth element RH is included in the R-T-B based permanent magnet.
    Type: Grant
    Filed: March 28, 2019
    Date of Patent: October 19, 2021
    Assignee: TDK CORPORATION
    Inventors: Yuki Nagamine, Masashi Miwa, Yoshinori Fujikawa
  • Patent number: 11145444
    Abstract: An R-T-B-based sintered magnet 2 contains a rare earth element R, a transition metal element T, B, Ga, and O, the sintered magnet 2 includes a magnet body 4 and an oxidized layer 6 covering the magnet body 4, the magnet body 4 includes main phase grains 8 containing a crystal of R2T14B and a grain boundary phase 1 positioned between the main phase grains 8 and containing R, the oxidized layer 6 includes a plurality of oxide phases 3A containing R, T, Ga, and O, the oxide phase 3A satisfies the following Formulas (1) and (2) regarding the content (unit: atom %) of each element, and the oxide phase 3A in the oxidized layer 6 covers the grain boundary phase 1 in the magnet body 4. 0.3?[R]/[T]?0.5??(1) 0.2?[O]/([R]+[T]+[Ga]+[O])?0.
    Type: Grant
    Filed: March 26, 2019
    Date of Patent: October 12, 2021
    Assignee: TDK Corporation
    Inventors: Mariko Fujiwara, Masashi Miwa
  • Publication number: 20210313099
    Abstract: Provided is a permanent magnet including a rare-earth element R (such as Nd), a transition metal element T (such as Fe), B, Zr, and Cu. The permanent magnet contains a plurality of main phase grains including Nd, T, and B, and grain boundary multiple junctions, the one grain boundary multiple junction is a grain boundary surrounded by three or more of the main phase grains, one of the grain boundary multiple junctions contains a ZrB2 crystal and an R—Cu-rich phase including R and Cu, a concentration of B in the one grain boundary multiple junction containing both the ZrB2 crystal and the R—Cu-rich phase is from 5 to 20 atomic %, a concentration of Cu in the one grain boundary multiple junction containing both the ZrB2 crystal and the R—Cu-rich phase is from 5 to 25 atomic %, and a surface layer part of the main phase grain includes at least one kind of heavy rare-earth element among Tb and Dy.
    Type: Application
    Filed: March 16, 2021
    Publication date: October 7, 2021
    Applicant: TDK Corporation
    Inventors: Masashi MIWA, Koji MIURA, Taeko TSUBOKURA
  • Publication number: 20210304929
    Abstract: Provided is a permanent magnet including a rare-earth element R (such as Nd), a transition metal element T (such as Fe), B, Zr, and Cu. The permanent magnet contains a plurality of main phase grains including Nd, T, and B, and grain boundary multiple junctions, the one grain boundary multiple junction is a grain boundary surrounded by three or more of the main phase grains, one of the grain boundary multiple junctions contains a ZrB2 crystal and an R—Cu-rich phase including R and Cu, Fe is contained in the ZrB2 crystal, a total concentration of Nd and Pr in the one grain boundary multiple junction containing both the ZrB2 crystal and the R—Cu-rich phase is higher than a total concentration of Nd and Pr in the main phase grain, a concentration of Cu in the one grain boundary multiple junction containing both the ZrB2 crystal and the R—Cu-rich phase is higher than a concentration of Cu in the main phase grain, and a unit of the concentration of each of Nd, Pr, and Cu is atomic %.
    Type: Application
    Filed: March 16, 2021
    Publication date: September 30, 2021
    Applicant: TDK Corporation
    Inventors: Masashi MIWA, Yoshitomo TANAKA, Koji MIURA, Taeko TSUBOKURA
  • Patent number: 10943717
    Abstract: An R-T-B based permanent magnet includes main phase grains composed of R2T14B type compound. R is a rare earth element. T is iron group element(s) essentially including Fe or Fe and Co. B is boron. An average grain size of the main phase grains is 0.8 ?m or more and 2.8 ?m or less. The R-T-B based permanent magnet contains at least C and Zr in addition to R, T, and B. B is contained at 0.75 mass % or more and 0.88 mass % or less. Zr is contained at 0.65 mass % or more and 5.00 mass % or less. A formula (1) of 5.0?[B]+[C]?[Zr]?5.6 is satisfied, where [B] is a B content represented by atom %, [C] is a C content represented by atom %, and [Zr] is a Zr content represented by atom %.
    Type: Grant
    Filed: February 23, 2017
    Date of Patent: March 9, 2021
    Assignee: TDK CORPORATION
    Inventors: Masashi Miwa, Takurou Iwasa
  • Publication number: 20200303102
    Abstract: A permanent magnet 2 includes Nd, Fe, and B, the permanent magnet 2 contains a plurality of main phase grains; and grain boundaries positioned between the main phase grains, the main phase grains include Nd, Fe, and B, at least a portion of the grain boundaries contains an R?—O—C phase, the R?—O—C phase includes a rare earth element R?, O, and C, the concentration of each of R?, O, and C in the R?—O—C phase is higher compared to the main phase grains, the permanent magnet 2 comprises a surface layer portion 21 and a central portion 22, the surface layer portion 21 is positioned on the surface side of the permanent magnet 2, the central portion 22 is positioned on the inner side of the permanent magnet 2, the proportion of the area of the R?—O—C phase occupying in a cross-section of the surface layer portion 21 is S1 %, the proportion of the area of the R?—O—C phase occupying in a cross-section of the central portion 22 is S2%, and S1 is higher than S2.
    Type: Application
    Filed: March 14, 2020
    Publication date: September 24, 2020
    Applicant: TDK Corporation
    Inventor: Masashi MIWA
  • Patent number: 10784028
    Abstract: An R-T-B based permanent magnet includes main phase grains composed of R2T14B type compound. R is a rare earth element. T is iron group element(s) essentially including Fe or Fe and Co. B is boron. An average grain size of the main phase grains is 0.8 ?m to 2.8 ?m. The R-T-B based permanent magnet contains at least C and Ga in addition to R, T, and B. B is contained at 0.71 mass % to 0.86 mass %. C is contained at 0.13 mass % to 0.34 mass %. Ga is contained at 0.40 mass % to 1.80 mass %. A formula (1) of 0.14?[C]/([B]+[C])?0.30 is satisfied, where [B] is a B content represented by atom %, and [C] is a C content represented by atom %.
    Type: Grant
    Filed: February 23, 2017
    Date of Patent: September 22, 2020
    Assignee: TDK CORPORATION
    Inventors: Tamotsu Ishiyama, Masashi Miwa, Takashi Watanabe
  • Patent number: 10748686
    Abstract: An R-T-B based sintered magnet including a plural number of main phase particles having an R2T14B type crystal structure. R is at least one rare earth element essentially including heavy rare earth elements RH, T is at least one transition metal element essentially including Fe or Fe and Co, and B is boron. At least one of the main phase particles is a reverse core-shell main phase particle including a core part and a shell part, in which CRC/CRS>1.0 is satisfied when a total RH concentration (at %) in the core part is defined as CRC and a total RH concentration (at %) in the shell part is defined as CRS. An existence ratio of the reverse core-shell main phase particles is larger in a surface layer part of the magnet than in a central part of the magnet.
    Type: Grant
    Filed: March 29, 2018
    Date of Patent: August 18, 2020
    Assignee: TDK CORPORATION
    Inventors: Yoshinori Fujikawa, Masashi Miwa
  • Patent number: 10748685
    Abstract: An R-T-B based sintered magnet including main phase particles having an R2T14B type crystal structure. R is at least one rare earth element essentially including a heavy rare-earth element RH. T is at least one transition metal element essentially including Fe or Fe and Co. B is boron. At least one of the main phase particles includes low RH crystal phases inside the main phase particle. The low RH crystal phases include the R2T14B type crystal structure, wherein an RH concentration in the low RH crystal phases is relatively lower than the RH concentration in the whole main phase particles. The R-T-B based sintered magnet may satisfy rs?rc?20% when an existence ratio of the main phase particles including the low RH crystal phases in a magnet surface layer part is rs (%) and the same in a magnet central part is rc (%).
    Type: Grant
    Filed: March 29, 2018
    Date of Patent: August 18, 2020
    Assignee: TDK CORPORATION
    Inventors: Yoshinori Fujikawa, Masashi Miwa
  • Patent number: D983716
    Type: Grant
    Filed: May 7, 2021
    Date of Patent: April 18, 2023
    Assignee: AISIN CORPORATION
    Inventors: Masashi Miwa, Takahisa Kobayashi, Norio Kato, Kimihiro Kinoshita