Patents by Inventor Takafumi Hara

Takafumi Hara 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: 11427726
    Abstract: According to one embodiment, an ink which can be decolored upon heating is provided. Colored images can be formed with the ink by various methods, such as ink jetting or the like, then later the images can be decolored with heat. An ink according to an embodiment contains a color developable compound, a color developing agent that causes the color developable compound to develop a color, a nonaqueous solvent, and a decoloring agent that is insoluble in the nonaqueous solvent and decolors the color developable compound upon heating.
    Type: Grant
    Filed: August 20, 2019
    Date of Patent: August 30, 2022
    Assignee: TOSHIBA TEC KABUSHIKI KAISHA
    Inventors: Maiko Miyoshi, Tsuyoshi Itou, Takafumi Hara
  • Publication number: 20220247328
    Abstract: An inverter control device 200 includes a current control unit 210 that outputs a voltage commands (Vd*, Vq*), a modulation wave control unit 220 that generates a modulation wave based on the voltage commands (Vd*, Vq*), a pulse generation unit 230 that generates a PWM pulse for controlling an inverter 100 using a modulation wave and a carrier wave of a predetermined frequency, and a pulse shift unit 250 that corrects the phase of the PWM pulse such that the PWM pulse is output in a phase corresponding to a harmonic of a predetermined order of the modulation wave in the near-zero-cross region including the zero-cross point at which the modulation wave changes across 0.
    Type: Application
    Filed: July 31, 2020
    Publication date: August 4, 2022
    Inventors: Toshiyuki AJIMA, Takafumi HARA, Akihiro ASHIDA, Hirokazu MATSUI
  • Patent number: 11325641
    Abstract: An object of the present invention is to provide an electric power steering apparatus capable of improving reliability of a drive device for a three-phase synchronous motor without increasing a cost of the drive device. A control device for controlling an electric power steering apparatus according to the present invention is a control device for controlling an electric power steering apparatus using a three-phase synchronous motor as a force assisting in a steering operation, includes: a rotational position estimation unit that estimates a position of a rotor of the three-phase synchronous motor on the basis of a neutral point potential or a virtual neutral point potential of the three-phase synchronous motor; and a command signal computing unit that computes a command signal to the three-phase synchronous motor on the basis of the position of the rotor estimated by the rotational position estimation unit.
    Type: Grant
    Filed: June 13, 2016
    Date of Patent: May 10, 2022
    Assignee: Hitachi Astemo, Ltd.
    Inventors: Takafumi Hara, Toshiyuki Ajima, Mitsuo Sasaki, Yoshitaka Iwaji, Shigehisa Aoyagi, Takumi Hisazumi
  • Patent number: 11290036
    Abstract: An applied voltage decision unit 510 performs in parallel, a process of determining three-phase AC commands V1u* to V1w* of a voltage applied to a motor by an inverter based on a position, of a rotor of a motor, detected by a position sensor with an output A, and a process of determining three-phase AC commands V2u* to V2w* of the voltage applied to the motor by the inverter based on a neutral point voltage VN of the motor. A PWM modulator 507 alternately outputs a PWM signal according to the three-phase AC commands V1u* to V1w* and a PWM signal according to the three-phase AC commands V2u* to V2w* to the inverter. A control device determines whether or not the position sensor with the output A has failed by comparing the position, of the rotor, detected by the position sensor with the output A with a position, of the rotor, estimated from a neutral point voltage VN of the motor.
    Type: Grant
    Filed: January 17, 2019
    Date of Patent: March 29, 2022
    Assignee: Hitachi Astemo, Ltd.
    Inventors: Shigehisa Aoyagi, Takafumi Hara, Yoshitaka Sugiyama, Masaki Kashima
  • Publication number: 20220050394
    Abstract: According to one embodiment, a colorable material capable of achieving a high image density during coloration is provided. A colorable material according to an embodiment contains: colorable particles including porous particles as a color developing agent composed of an inorganic oxide and a color developable agent carried on the porous particles; and a thermoplastic resin coating the colorable particles.
    Type: Application
    Filed: May 11, 2021
    Publication date: February 17, 2022
    Applicant: TOSHIBA TEC KABUSHIKI KAISHA
    Inventors: Maiko MIYOSHI, Tsuyoshi ITOU, Takafumi HARA
  • Publication number: 20220050397
    Abstract: A method for producing a capsule toner includes preparing core particles; preparing a shell fine particle dispersion liquid having a surface tension of 50 mN/m or more, as measured at 25° C., by dissolving a polyester resin in an organic solvent, thereafter performing neutralization with a neutralizer, and thereafter forming the polyester resin into fine particles; adjusting the surface tension of the shell fine particle dispersion liquid to less than 50 mN/m, as measured at 25° C., by adding a substance that does not include a surfactant to the shell fine particle dispersion liquid; and adhering the shell fine particle dispersion liquid to the surfaces of the core particles. The substance dissolves in or mixes with water and (i) has a vapor pressure equal to or greater than the vapor pressure of water or (ii) has a vapor pressure less than the vapor pressure of water and can be azeotropic with water.
    Type: Application
    Filed: August 17, 2020
    Publication date: February 17, 2022
    Applicant: TOSHIBA TEC KABUSHIKI KAISHA
    Inventors: Takafumi HARA, Satoshi ARAKI
  • Publication number: 20220049067
    Abstract: According to one embodiment, a high-definition and decolorable image is formed. A method for producing a colorable material according to an embodiment includes supplying a first solution containing a color developable agent and a first solvent to a color developing agent in the form of a powder which is insoluble in the first solvent so that a first mixture of the first solution and the color developing agent maintains the powder state, and removing the first solvent from the first mixture, thereby obtaining a powder of colorable particles containing the color developable agent and the color developing agent.
    Type: Application
    Filed: May 10, 2021
    Publication date: February 17, 2022
    Applicant: TOSHIBA TEC KABUSHIKI KAISHA
    Inventors: Tsuyoshi ITOU, Maiko MIYOSHI, Takafumi HARA
  • Publication number: 20220029573
    Abstract: In Steps S54 to S55, when a change rate ??* of a torque command value to a motor 10 is equal to or greater than a predetermined value, a frequency switching speed ?fc of a carrier frequency fc is set based on the number of rotations N of the motor 10 so that a response frequency ?fc of a frequency switching speed ?fc of the carrier frequency fc becomes faster than a response frequency ?ACR of a current control unit 70. In Steps S54 and S56, when the change rate ??* of the torque command value to the motor 10 is less than a predetermined value, the frequency switching speed ?fc of the carrier frequency fc is set based on a torque command value ?* to the motor 10 and the number of rotations N of the motor 10 regardless of the response frequency ?ACR of the current control unit 70.
    Type: Application
    Filed: November 14, 2019
    Publication date: January 27, 2022
    Applicant: HITACHI ASTEMO, LTD.
    Inventors: Midori TAKAOKA, Takafumi HARA, Shigehisa AOYAGI, Hirokazu MATSUI, Shigeyuki NONOMURA
  • Patent number: 11228271
    Abstract: Provides are a control device for a three-phase synchronous motor in which a position detection accuracy of a rotor can be improved when one three-phase synchronous motor is driven by a plurality of inverters, and an electric power steering device using the same. A control device for a three-phase synchronous motor includes: a three-phase synchronous motor including a first three-phase winding and a second three-phase winding; a first inverter connected to the first three-phase winding; a second inverter connected to the second three-phase winding; a first control device that controls the first inverter on the basis of a rotor position of the three-phase synchronous motor; and a second control device that controls the second inverter on the basis of the rotor position of the three-phase synchronous motor. The first control device estimates the rotor position on a basis of a neutral point potential of the first three-phase winding and a neutral point potential of the second three-phase winding.
    Type: Grant
    Filed: July 13, 2018
    Date of Patent: January 18, 2022
    Assignee: Hitachi Astemo, Ltd.
    Inventors: Takafumi Hara, Shigehisa Aoyagi, Toshiyuki Ajima, Hiroyuki Ota, Yoshitaka Sugiyama
  • Patent number: 11222150
    Abstract: The invention is directed to modeling of heat and vibration for structures. Therefore, with a traditional model division for each component, one-to-one correspondence between the models and the components is not necessarily realized. There has been a problem in that it is difficult to divide the models. To solve the above problem, a simulation program according to the present invention includes a first model for calculating a first vehicle characteristics parameter, a second model for calculating a second vehicle characteristics parameter to transfer energy without converting the energy, and an interface model for performing conversion calculation of the first vehicle characteristics parameter and the second vehicle characteristics parameter.
    Type: Grant
    Filed: January 19, 2017
    Date of Patent: January 11, 2022
    Assignee: Hitachi Astemo, Ltd.
    Inventors: Taizou Miyazaki, Masaru Yamasaki, Takafumi Hara, Katsuhiro Hoshino, Kazuto Oyama, Takeshi Yoshida
  • Patent number: 11215510
    Abstract: In a thermal infrared detector having trench structures, at least one sensor element is provided between the trench structures, an etching hole through which the sensor element is hollowed out and thereby thermally insulated is provided in a substrate rear surface or on the periphery of a pixel area, and an opening portion is provided below the pixel area.
    Type: Grant
    Filed: November 8, 2016
    Date of Patent: January 4, 2022
    Assignee: Mitsubishi Electric Corporation
    Inventors: Satoi Kobayashi, Takaki Sugino, Takafumi Hara, Yuji Kawano
  • Publication number: 20210384859
    Abstract: A random value integration unit 175 outputs a random value output from a random value generation unit 174 in a diffusion width Rand output from a diffusion width generation unit 173 by a product of an output of the random value generation unit 174 and an output of the diffusion width generation unit 173. A triangular wave signal generation unit 176 generates a triangular wave signal corresponding to a second carrier frequency fc2 which is obtained by adding the random value output from the random value integration unit 175 to a first carrier frequency fc1 which is an output of a carrier frequency setting unit 171. That is, a frequency obtained by increasing the diffusion width of the first carrier frequency fc1 is used as the second carrier frequency fc2, and the second carrier frequency is used as the carrier frequency.
    Type: Application
    Filed: September 12, 2019
    Publication date: December 9, 2021
    Applicant: HITACHI ASTEMO, LTD.
    Inventors: Takafumi HARA, Midori TAKAOKA, Toshiyuki AJIMA, Hirokazu MATSUI, Akihiro ASHIDA
  • Patent number: 11082640
    Abstract: An infrared camera includes a lens unit including a lens and a lens barrel, a heater that is provided at the lens unit and heats the lens, an infrared image sensor that captures an image using infrared light focused by the lens, a chassis that is fixed to an external surface side of the lens barrel while being thermally insulated from the lens unit and contains the infrared image sensor, and a light-blocking member that is located between the lens barrel and the infrared image sensor inside the chassis as viewed in a direction of an optical axis of the lens and blocks infrared light radiated toward the infrared image sensor and coming without passing through the lens, thus reducing the influence of infrared light coming without passing through the lens on capturing of an image.
    Type: Grant
    Filed: April 4, 2017
    Date of Patent: August 3, 2021
    Assignee: Mitsubishi Electric Corporation
    Inventors: Hideo Nagata, Hiroshi Sakanoue, Takafumi Hara
  • Patent number: 11009808
    Abstract: According to one embodiment, there is provided a toner cartridge used in an image forming apparatus including a processor which forms a toner pattern image on a photoconductive member, transfers the toner pattern image on a medium, and changes an image forming condition based on a detection result obtained by optically detecting the toner pattern image transferred onto the medium, the toner cartridge including: a toner accommodating container accommodating a toner, and a memory. The memory stores reference data which is determined according to toner characteristics in the toner accommodating container, and is used for applying a reference value for an optical detection result of a toner pattern formed by the toner on the medium.
    Type: Grant
    Filed: September 17, 2020
    Date of Patent: May 18, 2021
    Assignee: TOSHIBA TEC KABUSHIKI KAISHA
    Inventors: Tsuyoshi Itou, Kazuhisa Takeda, Masahiro Ikuta, Takafumi Hara, Hiromichi Mitamura, Shigeru Fujiwara, Hisanobu Ajima
  • Patent number: 10962894
    Abstract: A decolorizable toner allows for easy distinguishing between a sheet which can be reused and a sheet which is hardly able to be reused from each other. The decolorizable toner includes a color developable compound, a color developing agent, a decolorizing agent, a magnetic material, and a binder resin. The color developable compound is a precursor compound of a dye. The color developing agent is an electron accepting compound which donates a proton to the color developable compound. The decolorizing agent is a compound which inhibits a coloring reaction between the color developable compound and the color developing agent.
    Type: Grant
    Filed: January 23, 2020
    Date of Patent: March 30, 2021
    Assignee: TOSHIBA TEC KABUSHIKI KAISHA
    Inventors: Tsuyoshi Itou, Takafumi Hara
  • Patent number: 10962895
    Abstract: A decolorizable toner allows for easy distinguishing between a sheet which can be reused and a sheet which is hardly able to be reused from each other. The decolorizable toner includes a color developable compound, a color developing agent, a decolorizing agent, a magnetic material, and a binder resin. The color developable compound is a precursor compound of a dye. The color developing agent is an electron accepting compound which donates a proton to the color developable compound. The decolorizing agent is a compound which inhibits a coloring reaction between the color developable compound and the color developing agent.
    Type: Grant
    Filed: January 23, 2020
    Date of Patent: March 30, 2021
    Assignee: TOSHIBA TEC KABUSHIKI KAISHA
    Inventors: Tsuyoshi Itou, Takafumi Hara
  • Publication number: 20210091700
    Abstract: Provides are a control device for a three-phase synchronous motor in which a position detection accuracy of a rotor can be improved when one three-phase synchronous motor is driven by a plurality of inverters, and an electric power steering device using the same. A control device for a three-phase synchronous motor includes: a three-phase synchronous motor including a first three-phase winding and a second three-phase winding; a first inverter connected to the first three-phase winding; a second inverter connected to the second three-phase winding; a first control device that controls the first inverter on the basis of a rotor position of the three-phase synchronous motor; and a second control device that controls the second inverter on the basis of the rotor position of the three-phase synchronous motor. The first control device estimates the rotor position on a basis of a neutral point potential of the first three-phase winding and a neutral point potential of the second three-phase winding.
    Type: Application
    Filed: July 13, 2018
    Publication date: March 25, 2021
    Inventors: Takafumi HARA, Shigehisa AOYAGI, Toshiyuki AJIMA, Hiroyuki OTA, Yoshitaka SUGIYAMA
  • Publication number: 20210044243
    Abstract: An object of the present invention is to provide a motor control device that can suppress electromagnetic noises including a switching noise and to an electric vehicle system using the motor control device. A motor control device includes: a power converter that is controlled by a pulse width modulation signal; a motor that is driven by the power converter; and a controller that generates the pulse width modulation signal, based on a carrier signal. When switching between a first carrier frequency (fc1) of the carrier signal and a second carrier frequency (fc2) of the carrier signal, the controller varies proportions of the first carrier frequency and the second carrier frequency in accordance with a number of rotations of the motor, the second carrier frequency being higher than the first carrier frequency.
    Type: Application
    Filed: January 24, 2019
    Publication date: February 11, 2021
    Inventors: Takafumi HARA, Toshiyuki AJIMA, Akihiro ASHIDA
  • Publication number: 20210003939
    Abstract: According to one embodiment, there is provided a toner cartridge used in an image forming apparatus including a processor which forms a toner pattern image on a photoconductive member, transfers the toner pattern image on a medium, and changes an image forming condition based on a detection result obtained by optically detecting the toner pattern image transferred onto the medium, the toner cartridge including: a toner accommodating container accommodating a toner, and a memory. The memory stores reference data which is determined according to toner characteristics in the toner accommodating container, and is used for applying a reference value for an optical detection result of a toner pattern formed by the toner on the medium.
    Type: Application
    Filed: September 17, 2020
    Publication date: January 7, 2021
    Inventors: Tsuyoshi Itou, Kazuhisa Takeda, Masahiro Ikuta, Takafumi Hara, Hiromichi Mitamura, Shigeru Fujiwara, Hisanobu Ajima
  • Publication number: 20200412284
    Abstract: An applied voltage decision unit 510 performs in parallel, a process of determining three-phase AC commands V1u* to V1w* of a voltage applied to a motor by an inverter based on a position, of a rotor of a motor, detected by a position sensor with an output A, and a process of determining three-phase AC commands V2u* to V2w* of the voltage applied to the motor by the inverter based on a neutral point voltage VN of the motor. A PWM modulator 507 alternately outputs a PWM signal according to the three-phase AC commands V1u* to V1w* and a PWM signal according to the three-phase AC commands V2u* to V2w* to the inverter. A control device determines whether or not the position sensor with the output A has failed by comparing the position, of the rotor, detected by the position sensor with the output A with a position, of the rotor, estimated from a neutral point voltage VN of the motor.
    Type: Application
    Filed: January 17, 2019
    Publication date: December 31, 2020
    Inventors: Shigehisa AOYAGI, Takafumi HARA, Yoshitaka SUGIYAMA, Masaki KASHIMA