Patents by Inventor Tomoya Sakaguchi

Tomoya Sakaguchi 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: 10669480
    Abstract: A phosphorescent phosphor having a high afterglow luminance is provided. The phosphorescent phosphor comprises, as a matrix, a compound represented by MAl2O4, the metal element represented by M comprising Sr, Mg and Ba, and the phosphorescent phosphor containing, Eu as an activator, and Dy as a co-activator, wherein the content of Eu, in terms of molar ratio, is 0.001?Eu/(M+Eu+Dy)?0.05; the content of Dy, in terms of molar ratio, is 0.004?Dy/(M+Eu+Dy)?0.06; the content of Mg, in terms of molar ratio, is 0.02?Mg/(M+Eu+Dy)?0.1; the content of Ba, in terms of molar ratio, is 0.03?Ba/(M+Eu+Dy)?0.15; and the phosphorescent phosphor contains at least one alkali metal element of the group consisting of Li, Na, K and rubidium (Rb). Mg and Ba as well as the alkali metal element(s) contained in the phosphorescent phosphor provide an excellent phosphorescent phosphor having a high afterglow luminance.
    Type: Grant
    Filed: March 9, 2015
    Date of Patent: June 2, 2020
    Assignee: NEMOTO & CO., LTD.
    Inventors: Masashi Kato, Tomoya Sakaguchi
  • Patent number: 10519935
    Abstract: A condition monitoring system for a wind turbine includes: each sensor to sense a condition of equipment; a monitor device configured to generate a diagnosis parameter based on a detection result of each sensor; a data server configured to diagnose a failure of the equipment based on the diagnosis parameter; and a rotation angle sensor for sensing the nacelle's rotation speed. The data server is configured to correct the diagnosis parameter based on a sensed result of the rotation angle sensor, and diagnose whether the equipment has a failure by comparing the corrected diagnosis parameter with a predetermined threshold value.
    Type: Grant
    Filed: May 29, 2015
    Date of Patent: December 31, 2019
    Assignee: NTN CORPORATION
    Inventors: Tomoya Sakaguchi, Kouma Katou
  • Patent number: 10408267
    Abstract: A tapered roller bearing (31a) has a plurality of retainer segments (11a, 11d) each having a pocket to house a tapered roller (34a), and arranged so as to be continuously lined with each other in a circumferential direction between an outer ring (32a) and an inner ring (33a). The retainer segment (11a, 11d) is formed of a resin containing a filler material to lower a thermal linear expansion coefficient. In addition, a clearance (39a) is provided between the first retainer segment (11a) and the last retainer segment (11d) after the plurality of retainer segments (11a, 11d) have been arranged in the circumferential direction without providing any clearance. Here a circumferential range (R) of the clearance (39a) is larger than 0.075% of a circumference of a circle passing through a center of the retainer segment (11a, 11d) and smaller than 0.12% thereof at room temperature.
    Type: Grant
    Filed: September 22, 2017
    Date of Patent: September 10, 2019
    Assignee: NTN CORPORATION
    Inventors: Tatsuya Omoto, Eiichi Nakamizo, Tomoya Sakaguchi
  • Patent number: 10337958
    Abstract: A vibration analysis method includes the steps of: inputting damage data of a rolling bearing; calculating, by a dynamics analysis program, a history of an exciting force occurring to the rolling bearing due to damage when a rotational shaft of the rolling bearing is rotated; calculating, by a mode analysis program, a vibration characteristics model of the bearing device; and calculating a vibration waveform at a predetermined position on the bearing device by applying to the vibration characteristics model the history of the exciting force calculated in the step of calculating a history of an exciting force.
    Type: Grant
    Filed: December 19, 2013
    Date of Patent: July 2, 2019
    Assignee: NTN CORPORATION
    Inventors: Tomoya Sakaguchi, Hideyuki Tsutsui
  • Patent number: 10190576
    Abstract: A roller bearing comprises an outer ring, an inner ring, a plurality of rollers arranged between said outer ring and said inner ring; and a plurality of retainer segments having a plurality of column parts extending in a direction along a shaft so as to form a pocket for holding said roller. A connection part extends in a circumferential direction so as to connect the plurality of column parts, and continuously lined with each other in the circumferential direction between said outer ring and said inner ring, in which a corner of a circumferential end face is chamfered. Also provided is a spacer arranged between the circumferentially arranged first retainer segment and last retainer segment, wherein a chamfered part is provided at a corner of a circumferential spacer end face of the space. The roller bearing can be used in a main shaft support structure of a wind-power generator.
    Type: Grant
    Filed: July 6, 2017
    Date of Patent: January 29, 2019
    Assignee: NTN CORPORATION
    Inventors: Tatsuya Omoto, Shoichi Hioki, Mitsuo Sasabe, Eiichi Nakamizo, Tomoya Sakaguchi
  • Patent number: 10100815
    Abstract: Frequency analysis units are configured to perform a frequency analysis of vibrations detected by vibration sensors, respectively. A natural frequency detection unit is configured to detect a natural frequency of a wind turbine in accordance with a direction of a nacelle, based on results of the frequency analysis. A change ratio calculation unit calculates a decrease ratio in the natural frequency detected by the natural frequency detection unit. An abnormality detection unit determines that an abnormality is present in the wind turbine if the decrease ratio in the natural frequency calculated by the change ratio calculation unit exceeds a threshold value.
    Type: Grant
    Filed: September 3, 2014
    Date of Patent: October 16, 2018
    Assignee: NTN CORPORATION
    Inventor: Tomoya Sakaguchi
  • Patent number: 10047726
    Abstract: A condition monitoring system for a wind turbine comprises: a sensor which senses a condition of a yaw bearing; a monitor device which generates a diagnosis parameter based on a detection result of the sensor; a sensor which senses a rotating angular velocity of a nacelle and that of a main shaft; and a data server which diagnoses a failure of the yaw bearing based on the diagnosis parameter. The data server diagnoses whether the yaw bearing has a failure, based on a variation of the diagnosis parameter from an initial value thereof when the nacelle has a rotating angular velocity within a non-zero, first prescribed range and the main shaft has a rotating angular velocity within a second prescribed range.
    Type: Grant
    Filed: July 9, 2015
    Date of Patent: August 14, 2018
    Assignee: NTN Corporation
    Inventor: Tomoya Sakaguchi
  • Publication number: 20180010639
    Abstract: A tapered roller bearing (31a) has a plurality of retainer segments (11a, 11d) each having a pocket to house a tapered roller (34a), and arranged so as to be continuously lined with each other in a circumferential direction between an outer ring (32a) and an inner ring (33a). The retainer segment (11a, 11d) is formed of a resin containing a filler material to lower a thermal linear expansion coefficient. In addition, a clearance (39a) is provided between the first retainer segment (11a) and the last retainer segment (11d) after the plurality of retainer segments (11a, 11d) have been arranged in the circumferential direction without providing any clearance. Here a circumferential range (R) of the clearance (39a) is larger than 0.075% of a circumference of a circle passing through a center of the retainer segment (11a, 11d) and smaller than 0.12% thereof at room temperature.
    Type: Application
    Filed: September 22, 2017
    Publication date: January 11, 2018
    Inventors: Tatsuya OMOTO, Eiichi NAKAMIZO, Tomoya SAKAGUCHI
  • Patent number: 9810263
    Abstract: A tapered roller bearing (31a) has a plurality of retainer segments (11a, 11d) each having a pocket to house a tapered roller (34a), and arranged so as to be continuously lined with each other in a circumferential direction between an outer ring (32a) and an inner ring (33a). The retainer segment (11a, 11d) is formed of a resin containing a filler material to lower a thermal linear expansion coefficient. In addition, a clearance (39a) is provided between the first retainer segment (11a) and the last retainer segment (11d) after the plurality of retainer segments (11a, 11d) have been arranged in the circumferential direction without providing any clearance. Here a circumferential range (R) of the clearance (39a) is larger than 0.075% of a circumference of a circle passing through a center of the retainer segment (11a, 11d) and smaller than 0.12% thereof at room temperature.
    Type: Grant
    Filed: May 16, 2014
    Date of Patent: November 7, 2017
    Assignee: NTN CORPORATION
    Inventors: Tatsuya Omoto, Eiichi Nakamizo, Tomoya Sakaguchi
  • Publication number: 20170306929
    Abstract: A roller bearing comprises an outer ring, an inner ring, a plurality of rollers arranged between said outer ring and said inner ring; and a plurality of retainer segments having a plurality of column parts extending in a direction along a shaft so as to form a pocket for holding said roller. A connection part extends in a circumferential direction so as to connect the plurality of column parts, and continuously lined with each other in the circumferential direction between said outer ring and said inner ring, in which a corner of a circumferential end face is chamfered. Also provided is a spacer arranged between the circumferentially arranged first retainer segment and last retainer segment, wherein a chamfered part is provided at a corner of a circumferential spacer end face of the space. The roller bearing can be used in a main shaft support structure of a wind-power generator.
    Type: Application
    Filed: July 6, 2017
    Publication date: October 26, 2017
    Inventors: Tatsuya OMOTO, Shoichi HIOKI, Mitsuo SASABE, Eiichi NAKAMIZO, Tomoya SAKAGUCHI
  • Publication number: 20170260968
    Abstract: A displacement sensor detects a displacement of a main shaft, thereby detecting a relative displacement between an inner race and an outer race of a bearing. A data processor carries out an abnormality diagnosis for the bearing based on a detected value of the displacement sensor. The data processor carries out an abnormality diagnosis based on a difference between the detected value of the displacement sensor under a first axial load condition for the bearing and the detected value of the displacement sensor under a second axial load condition different from the first axial load condition. Thereby, an abnormality diagnosing apparatus for a rolling bearing is provided, by which a highly accurate abnoiiiiality diagnosis can be implemented even if installation states of a displacement sensor and an object to be measured are changed due to maintenance or repair.
    Type: Application
    Filed: August 25, 2015
    Publication date: September 14, 2017
    Inventors: Hideyuki TSUTSUI, Tomoya SAKAGUCHI
  • Publication number: 20170234304
    Abstract: A condition monitoring system for a wind turbine comprises: a sensor which senses a condition of a yaw bearing; a monitor device which generates a diagnosis parameter based on a detection result of the sensor; a sensor which senses a rotating angular velocity of a nacelle and that of a main shaft; and a data server which diagnoses a failure of the yaw bearing based on the diagnosis parameter. The data server diagnoses whether the yaw bearing has a failure, based on a variation of the diagnosis parameter from an initial value thereof when the nacelle has a rotating angular velocity within a non-zero, first prescribed range and the main shaft has a rotating angular velocity within a second prescribed range.
    Type: Application
    Filed: July 9, 2015
    Publication date: August 17, 2017
    Inventor: Tomoya SAKAGUCHI
  • Patent number: 9732734
    Abstract: A roller bearing comprises an outer ring, an inner ring, a plurality of rollers arranged between the outer ring and the inner ring, and a plurality of retainer segments having a plurality of column parts extending in a direction along a shaft so as to form a pocket for holding the roller, and connection parts and extending in a circumferential direction to connect the plurality of column parts, and continuously lined with each other in the circumferential direction between the outer ring and the inner ring. The column part is positioned at an circumferential end of the retainer segment. Here, a circumferential outer side end face of the column part positioned at the end is flat, and a circumferential inner side end face of the column part positioned at said end is provided with a recess recessed in the circumferential direction to reduce the thickness of the column part.
    Type: Grant
    Filed: November 5, 2014
    Date of Patent: August 15, 2017
    Assignee: NTN CORPORATION
    Inventors: Tatsuya Omoto, Shoichi Hioki, Mitsuo Sasabe, Eiichi Nakamizo, Tomoya Sakaguchi
  • Patent number: 9664231
    Abstract: A tapered roller bearing (31a) has a plurality of retainer segments (11a, 11d) each having a pocket to house a tapered roller (34a), and arranged so as to be continuously lined with each other in a circumferential direction between an outer ring (32a) and an inner ring (33a). The retainer segment (11a, 11d) is formed of a resin containing a filler material to lower a thermal linear expansion coefficient. In addition, a clearance (39a) is provided between the first retainer segment (11a) and the last retainer segment (11d) after the plurality of retainer segments (11a, 11d) have been arranged in the circumferential direction without providing any clearance. Here a circumferential range (R) of the clearance (39a) is larger than 0.075% of a circumference of a circle passing through a center of the retainer segment (11a, 11d) and smaller than 0.12% thereof at room temperature.
    Type: Grant
    Filed: April 22, 2015
    Date of Patent: May 30, 2017
    Assignee: NTN CORPORATION
    Inventors: Tatsuya Omoto, Eiichi Nakamizo, Tomoya Sakaguchi
  • Publication number: 20170130700
    Abstract: A condition monitoring system for a wind turbine includes: each sensor to sense a condition of equipment; a monitor device configured to generate a diagnosis parameter based on a detection result of each sensor; a data server configured to diagnose a failure of the equipment based on the diagnosis parameter; and a rotation angle sensor for sensing the nacelle's rotation speed. The data server is configured to correct the diagnosis parameter based on a sensed result of the rotation angle sensor, and diagnose whether the equipment has a failure by comparing the corrected diagnosis parameter with a predetermined threshold value.
    Type: Application
    Filed: May 29, 2015
    Publication date: May 11, 2017
    Inventors: Tomoya SAKAGUCHI, Kouma KATOU
  • Publication number: 20160319190
    Abstract: A phosphorescent phosphor having a high afterglow luminance is provided. The phosphorescent phosphor comprises, as a matrix, a compound represented by MAl2O4, the metal element represented by M comprising Sr, Mg and Ba, and the phosphorescent phosphor containing, Eu as an activator, and Dy as a co-activator, wherein the content of Eu, in terms of molar ratio, is 0.001?Eu/(M+Eu+Dy)?0.05; the content of Dy, in terms of molar ratio, is 0.004?Dy/(M+Eu+Dy)?0.06; the content of Mg, in terms of molar ratio, is 0.02?Mg/(M+Eu+Dy)?0.1; the content of Ba, in terms of molar ratio, is 0.03?Ba/(M+Eu+Dy)?0.15; and the phosphorescent phosphor contains at least one alkali metal element of the group consisting of Li, Na, K and rubidium (Rb). Mg and Ba as well as the alkali metal element(s) contained in the phosphorescent phosphor provide an excellent phosphorescent phosphor having a high afterglow luminance.
    Type: Application
    Filed: March 9, 2015
    Publication date: November 3, 2016
    Applicant: NEMOTO LUMI-MATERIALS COMPANY LIMITED
    Inventors: Masashi KATO, Tomoya SAKAGUCHI
  • Patent number: 9423290
    Abstract: An effective value operation unit calculates an effective value of a vibration waveform of a bearing, the vibration waveform being measured by using a vibration sensor. An envelope processing unit performs envelope processing on the vibration waveform measured by using the vibration sensor, thereby generating an envelope waveform of the vibration waveform. An effective value operation unit calculates an effective value of an AC component of the envelope waveform generated by the envelope processing unit. A diagnostic unit diagnoses an abnormality of the bearing based on the effective value of the vibration waveform calculated by the effective value operation unit and the effective value of the AC component of the envelope waveform calculated by the effective value operation unit.
    Type: Grant
    Filed: December 24, 2010
    Date of Patent: August 23, 2016
    Assignee: NTN CORPORATION
    Inventors: Tomoya Sakaguchi, Nobuyuki Ninoyu, Junichi Hirata, Yasuhiko Sakakibara
  • Publication number: 20160215764
    Abstract: Frequency analysis units are configured to perform a frequency analysis of vibrations detected by vibration sensors, respectively. A natural frequency detection unit is configured to detect a natural frequency of a wind turbine in accordance with a direction of a nacelle, based on results of the frequency analysis. A change ratio calculation unit calculates a decrease ratio in the natural frequency detected by the natural frequency detection unit. An abnormality detection unit determines that an abnormality is present in the wind turbine if the decrease ratio in the natural frequency calculated by the change ratio calculation unit exceeds a threshold value.
    Type: Application
    Filed: September 3, 2014
    Publication date: July 28, 2016
    Inventor: Tomoya SAKAGUCHI
  • Publication number: 20160187226
    Abstract: A vibration analysis method includes the steps of: inputting data about damage of a rolling bearing; calculating, by a dynamics analysis program, a history of a displacement between inner and outer rings occurring to the rolling bearing due to the damage when a rotational shaft of the rolling bearing rotates; calculating a vibration characteristics model of the bearing device by a mode analysis program; and calculating a vibration waveform at a predetermined position on the bearing device by applying, to the vibration characteristics model, a history of an exciting force obtained by multiplying the displacement between the inner and outer rings calculated in the step of calculating a history, by a bearing spring constant.
    Type: Application
    Filed: July 1, 2014
    Publication date: June 30, 2016
    Inventors: Hideyuki TSUTSUI, Tomoya SAKAGUCHI
  • Patent number: 9335317
    Abstract: A status monitoring system for accurately determining the contaminant water concentration in a lubricant oil used in a rolling device includes a contaminant water concentration monitoring device configured to monitor the contaminant water concentration in the lubricant oil. The contaminant water concentration monitoring device includes an electrostatic capacitance detector and an oil temperature measuring instrument, which are configured to detect the electrostatic capacitance and the oil temperature of the lubricant oil, respectively, and a water concentration calculation section configured to calculate the contaminant water concentration from the detected electrostatic capacitance and oil temperature in accordance with a predetermined rule.
    Type: Grant
    Filed: February 24, 2012
    Date of Patent: May 10, 2016
    Assignee: NTN CORPORATION
    Inventors: Yukio Matsubara, Noriaki Miwa, Takakazu Kitagawa, Tomoya Sakaguchi, Masayuki Kawakita, Hisamitsu Maeda