Patents by Inventor Ken Kitahara

Ken Kitahara 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: 20240136871
    Abstract: A rotor used for a motor includes a rotor core, and a plurality of permanent magnets embedded in a corresponding plurality of embedding holes in the rotor core configured to include flux barriers at both ends of the plurality of embedding holes in the rotor core and to include a plurality of magnetic poles. The rotor core includes a plurality of grooves on an outer peripheral surface, the plurality of grooves, with the two paired grooves, are away from an axis that becomes the q-axis when the motor is operated, and are arranged symmetrically about the axis, and the rotor core has such a cross-section that a first angle between two lines passing through the two grooves and the center of the rotor core is smaller than a second angle between the axis-side end face of the two flux barriers adjacent to each other across the axis.
    Type: Application
    Filed: February 15, 2022
    Publication date: April 25, 2024
    Applicants: TOYOTA JIDOSHA KABUSHIKI KAISHA, AISIN CORPORTION
    Inventors: Ken JOZAKI, Toshinori OKOCHI, Yoshizumi KITAHARA, Takahiro ODAGI, Masayuki IKEMOTO
  • Patent number: 11939695
    Abstract: A quartz glass crucible 1 having a cylindrical side wall portion 10a, a bottom portion 10b, and a corner portion 10c includes a transparent layer 11 as an innermost layer made of quartz glass, a semi-molten layer 13 as an outermost layer made of raw material silica powder solidified in a semi-molten state, and a bubble layer 12 made of quartz glass interposed therebetween. An infrared transmissivity of the corner portion 10c in a state where the semi-molten layer 13 is removed is 25 to 51%, the infrared transmissivity of the corner portion 10c in the state where the semi-molten layer 13 is removed is lower than an infrared transmissivity of the side wall portion 10a, and the infrared transmissivity of the side wall portion 10a in the state where the semi-molten layer 13 is removed is lower than an infrared transmissivity of the bottom portion 10b.
    Type: Grant
    Filed: December 16, 2019
    Date of Patent: March 26, 2024
    Assignee: SUMCO CORPORATION
    Inventors: Ken Kitahara, Masanori Fukui, Hiroshi Kishi, Tomokazu Katano, Eriko Kitahara
  • Patent number: 11535546
    Abstract: A silica glass crucible includes a cylindrical side wall portion, a curved bottom portion, and a corner portion that is provided between the side wall portion and the bottom portion and has a higher curvature than a curvature of the bottom portion, in which a first region provided from a crucible inner surface to a middle in a thickness direction, a second region that is provided outside the first region in the thickness direction and has a different strain distribution from the first region, and a third region that is provided outside the second region in the thickness direction and up to the crucible outer surface and has a different strain distribution from the second region, are provided, and internal residual stresses of the first region and the third region are compressive stresses, whereas an internal residual stress of the second region includes a tensile stress.
    Type: Grant
    Filed: November 2, 2018
    Date of Patent: December 27, 2022
    Assignee: SUMCO CORPORATION
    Inventors: Ken Kitahara, Masaru Sato, Takuma Yoshioka
  • Publication number: 20220090290
    Abstract: A quartz glass crucible 1 having a cylindrical side wall portion 10a, a bottom portion 10b, and a corner portion 10c connecting the side wall portion 10a and the bottom portion 10b to each other includes a transparent layer 11 made of quartz glass, and a bubble layer 12 made of quartz glass and formed outside the transparent layer 11. A ratio of an infrared transmittance of the corner portion 10c at a maximum thickness position of the corner portion 10c to an infrared transmittance of the side wall portion 10a is 0.3 or more and 0.99 or less, and an absolute value of a rate of change in infrared transmittance in a height direction along a wall surface of the crucible from a center of the bottom portion 10b toward an upper end of the side wall portion 10a is 3%/cm or less.
    Type: Application
    Filed: December 16, 2019
    Publication date: March 24, 2022
    Inventors: Takeshi FUJITA, Ken KITAHARA, Tomokazu KATANO, Eriko KITAHARA
  • Publication number: 20220090291
    Abstract: A quartz glass crucible 1 having a cylindrical side wall portion 10a, a bottom portion 10b, and a corner portion 10c includes a transparent layer 11 as an innermost layer made of quartz glass, a semi-molten layer 13 as an outermost layer made of raw material silica powder solidified in a semi-molten state, and a bubble layer 12 made of quartz glass interposed therebetween. An infrared transmissivity of the corner portion 10c in a state where the semi-molten layer 13 is removed is 25 to 51%, the infrared transmissivity of the corner portion 10c in the state where the semi-molten layer 13 is removed is lower than an infrared transmissivity of the side wall portion 10a, and the infrared transmissivity of the side wall portion 10a in the state where the semi-molten layer 13 is removed is lower than an infrared transmissivity of the bottom portion 10b.
    Type: Application
    Filed: December 16, 2019
    Publication date: March 24, 2022
    Inventors: Ken KITAHARA, Masanori FUKUI, Hiroshi KISHI, Tomokazu KATANO, Eriko KITAHARA
  • Publication number: 20200392032
    Abstract: A silica glass crucible includes a cylindrical side wall portion, a curved bottom portion, and a corner portion that is provided between the side wall portion and the bottom portion and has a higher curvature than a curvature of the bottom portion, in which a first region provided from a crucible inner surface to a middle in a thickness direction, a second region that is provided outside the first region in the thickness direction and has a different strain distribution from the first region, and a third region that is provided outside the second region in the thickness direction and up to the crucible outer surface and has a different strain distribution from the second region, are provided, and internal residual stresses of the first region and the third region are compressive stresses, whereas an internal residual stress of the second region includes a tensile stress.
    Type: Application
    Filed: November 2, 2018
    Publication date: December 17, 2020
    Inventors: Ken KITAHARA, Masaru SATO, Takuma YOSHIOKA
  • Patent number: 10243329
    Abstract: A tunable external resonator laser is mode-hop-free for broadband and has a laser chip which emits light; a lens which collimates the light emitted from the laser chip, a diffraction grating which diffracts the light collimated by the lens, a support body to which the diffraction grating is fixed, and a movable mirror which reflects the light diffracted by the diffraction grating, wherein the diffraction grating is arranged a prescribed distance apart from a Littman-type tunable external resonator laser arrangement in which the movable mirror rotates on a pivot which is the intersection point of the surface of said movable mirror and the surface of the diffraction grating.
    Type: Grant
    Filed: September 19, 2013
    Date of Patent: March 26, 2019
    Assignee: NATIONAL UNIVERSITY CORPORATION CHIBA UNIVERSITY
    Inventors: Kiyofumi Muro, Yuji Wakabayashi, Tomohisa Endo, Ken Kitahara
  • Patent number: 10024784
    Abstract: A vitreous silica crucible used to pull up silicon single crystal includes: a cylindrical straight body portion, a corner portion formed at a lower end of the straight body portion, and a bottom portion connected with the straight body portion via the corner portion, wherein the vitreous silica crucible further comprises: an opaque outer layer enclosing bubbles therein; and a transparent inner layer from which bubbles are removed, wherein the residual distortion's distribution obtained by measuring the silica glass's inner surface in a non-destructed state has an optical path difference which is 130 nm or less, which residual distortion's distribution is measured using a distortion-measuring apparatus which converts a linearly polarized light into circularly polarized light and then irradiates the crucible's wall.
    Type: Grant
    Filed: October 13, 2017
    Date of Patent: July 17, 2018
    Assignee: SUMCO CORPORATION
    Inventors: Toshiaki Sudo, Tadahiro Sato, Ken Kitahara, Eriko Kitahara
  • Patent number: 9964478
    Abstract: A destructive inspection method of a vitreous silica crucible for pulling a silicon single crystal evaluates a crack state of an inner surface of the vitreous silica crucible supported by a graphite susceptor when a load is instantaneously applied to at least one point on the inner surface via an automatic center punch while pushing the tip portion of the automatic center punch against the inner surface. The destructive inspection method can inspect the vitreous silica crucible under conditions as close to the actual conditions of use as possible.
    Type: Grant
    Filed: September 24, 2015
    Date of Patent: May 8, 2018
    Assignee: SUMCO CORPORATION
    Inventors: Ken Kitahara, Tadahiro Sato, Toshiaki Sudo, Eriko Kitahara, Takashi Watanabe
  • Patent number: 9932692
    Abstract: A vitreous silica crucible includes: a substantially cylindrical straight body portion having an opening on a top end and extending in a vertical direction; a curved bottom portion; and a corner portion connecting the straight body portion with the bottom portion and a curvature of which is greater than that of the bottom portion, wherein an inner surface of the crucible has a concavo-convex structure in which groove-shaped valleys are interposed between ridges, and an average interval of the ridges is 5-100 ?m.
    Type: Grant
    Filed: June 30, 2013
    Date of Patent: April 3, 2018
    Assignee: SUMCO CORPORATION
    Inventors: Toshiaki Sudo, Tadahiro Sato, Ken Kitahara, Eriko Kitahara
  • Publication number: 20180045639
    Abstract: A vitreous silica crucible used to pull up silicon single crystal includes: a cylindrical straight body portion, a corner portion formed at a lower end of the straight body portion, and a bottom portion connected with the straight body portion via the corner portion, wherein the vitreous silica crucible further comprises: an opaque outer layer enclosing bubbles therein; and a transparent inner layer from which bubbles are removed, wherein the residual distortion's distribution obtained by measuring the silica glass's inner surface in a non-destructed state has an optical path difference which is 130 nm or less, which residual distortion's distribution is measured using a distortion-measuring apparatus which converts a linearly polarized light into circularly polarized light and then irradiates the crucible's wall.
    Type: Application
    Filed: October 13, 2017
    Publication date: February 15, 2018
    Inventors: Toshiaki SUDO, Tadahiro SATO, Ken KITAHARA, Eriko KITAHARA
  • Patent number: 9863061
    Abstract: In an embodiment, a vitreous silica crucible 1 includes a cylindrical straight body portion 10a, a corner portion 10c formed at lower end of the straight body portion 10a, and a bottom portion 10b connected with the straight body portion 10a via the corner portion 10c. Moreover, the vitreous silica crucible 1 includes a bubble-containing opaque layer 11 constituting an outer layer, and a bubble-free transparent layer 12 constituting an inner layer. A boundary surface, between the opaque layer 11 and the transparent layer 12 in at least the straight body portion 10a, forms a periodic wave surface in a vertical direction. The vitreous silica crucible can suppress deformation under high temperature.
    Type: Grant
    Filed: December 25, 2014
    Date of Patent: January 9, 2018
    Assignee: SUMCO CORPORATION
    Inventors: Toshiaki Sudo, Tadahiro Sato, Ken Kitahara, Eriko Kitahara
  • Patent number: 9863059
    Abstract: A method for pulling silicon single crystal includes a process of placing a molded body between a susceptor's inner surface and a crucible's outer surface. The molded body is formed based on three-dimensional data of the inner surface shape of the susceptor which can hold the vitreous silica crucible and three-dimensional data of the crucible so as to make the susceptor's central axis and the crucible's central axis substantially aligned when it is placed between the susceptor's inner surface and the crucible's outer surface.
    Type: Grant
    Filed: June 29, 2013
    Date of Patent: January 9, 2018
    Assignee: SUMCO CORPORATION
    Inventors: Toshiaki Sudo, Tadahiro Sato, Ken Kitahara, Eriko Kitahara
  • Patent number: 9816917
    Abstract: In an embodiment, a distortion-measuring apparatus for measuring a distortion distribution of an entire vitreous silica crucible in a non-destructive way includes: a light source 11; a first polarizer 12 and a first quarter-wave plate 13 disposed between the light source 11 and an outer surface of a vitreous silica crucible wall; a camera 14 disposed inside of a vitreous silica crucible 1; a camera control mechanism 15 configured to control a photographing direction of the camera 14; a second polarizer 16 and a second quarter-wave plate 17 disposed between the camera 14 and an inner surface of the vitreous silica crucible wall. An optical axis of the second quarter-wave plate 17 inclines 90 degrees with respect to the first quarter-wave plate 13.
    Type: Grant
    Filed: December 25, 2014
    Date of Patent: November 14, 2017
    Assignee: SUMCO CORPORATION
    Inventors: Toshiaki Sudo, Tadahiro Sato, Ken Kitahara, Eriko Kitahara
  • Patent number: 9809902
    Abstract: The present invention provides a method for evaluating a vitreous silica crucible which can measure a three-dimensional shape of the inner surface of the crucible in a non-destructive manner.
    Type: Grant
    Filed: October 31, 2012
    Date of Patent: November 7, 2017
    Assignee: SUMCO CORPORATION
    Inventors: Toshiaki Sudo, Tadahiro Sato, Ken Kitahara, Eriko Kitahara, Makiko Kodama
  • Patent number: 9810526
    Abstract: A method for measuring a three-dimensional shape of an inner surface of a vitreous silica crucible which enables the measurement of the three-dimensional shape of the inner surface of the crucible without contaminating the inner surface of the crucible, is provided. According to the present invention, a method for measuring a three-dimensional shape of a vitreous silica crucible, including a fogging step to form a fog onto an inner surface of the vitreous silica crucible, a three-dimensional shape measuring step to measure a three-dimensional shape of the inner surface, by measuring a reflected light from the inner surface irradiated with light, is provided.
    Type: Grant
    Filed: October 31, 2012
    Date of Patent: November 7, 2017
    Assignee: SUMCO CORPORATION
    Inventors: Toshiaki Sudo, Tadahiro Sato, Ken Kitahara
  • Publication number: 20170292901
    Abstract: A destructive inspection method of a vitreous silica crucible for pulling a silicon single crystal evaluates a crack state of an inner surface of the vitreous silica crucible supported by a graphite susceptor when a load is instantaneously applied to at least one point on the inner surface via an automatic center punch while pushing the tip portion of the automatic center punch against the inner surface. The destructive inspection method can inspect the vitreous silica crucible under conditions as close to the actual conditions of use as possible.
    Type: Application
    Filed: September 24, 2015
    Publication date: October 12, 2017
    Inventors: Ken KITAHARA, Tadahiro SATO, Toshiaki SUDO, Eriko KITAHARA, Takashi WATANABE
  • Publication number: 20170292204
    Abstract: Spatial coordinates of multiple points on an inner surface of a vitreous silica crucible are measured prior to filling raw material in the vitreous silica crucible, and a three-dimensional shape of the inner surface of the vitreous silica crucible using a combination of polygons having vertex coordinates constituted by the respective measured points is specified (S11); a predictive value of an initial liquid surface level of the silicon melt in the vitreous silica crucible is preset (S12); a volume of the silicon melt satisfying the predictive value of the initial liquid surface level is obtained based on the three-dimensional shape of the inner surface of the vitreous silica crucible (S13); a weight of the silicon melt having the volume is obtained (S14); raw material having the weight is filled in the vitreous silica crucible (S15); a dipping control of the seed crystal is performed based on the predictive value of the initial liquid surface level (S17).
    Type: Application
    Filed: September 24, 2015
    Publication date: October 12, 2017
    Inventors: Tadahiro SATO, Eriko KITAHARA, Toshiaki SUDO, Ken KITAHARA
  • Patent number: 9758901
    Abstract: The present invention provides a vitreous silica crucible which inhibits a deformation even when used under a high temperature condition for a long time, and a method for manufacturing the same. The vitreous silica crucible comprises: a substantially cylindrical straight body portion having an opening on the top end and extending in a vertical direction, a curved bottom portion, and a corner portion connecting the straight body portion with the bottom portion and a curvature of which is greater than that of the bottom portion, wherein, the vitreous silica crucible comprises a transparent layer on the inside and a bubble layer on the outside thereof, a compressive stress layer in which compressive stress remains in the inner surface side of the transparent layer, and a tensile stress layer in which tensile stress remains and is adjacent to the compressive stress layer at a gradual rate of change of stress.
    Type: Grant
    Filed: May 31, 2013
    Date of Patent: September 12, 2017
    Assignee: SUMCO CORPORATION
    Inventors: Toshiaki Sudo, Ken Kitahara, Akihiro Aiba, Kazushi Ousyuya, Fumie Yoshida, Makiko Hinooka, Eriko Kitahara, Tadahiro Sato
  • Patent number: 9758900
    Abstract: Buckling of a vitreous silica crucible 12 or inward fall of a sidewall 15 is effectively suppressed. The vitreous silica crucible 12 includes the cylindrical sidewall 15 having an upward-opening rim, a mortar-shaped bottom 16 including a curve, and a round portion 17 connecting the sidewall 15 and the bottom 16. In the vitreous silica crucible 12 the per-unit area thermal resistance in the thickness direction of the sidewall 15 is higher than that of the round portion 17.
    Type: Grant
    Filed: October 31, 2012
    Date of Patent: September 12, 2017
    Assignee: SUMCO CORPORATION
    Inventors: Toshiaki Sudo, Tadahiro Sato, Ken Kitahara, Takuma Yoshioka, Hiroshi Kishi