Patents by Inventor Isao NAMIKAWA

Isao NAMIKAWA 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: 11400970
    Abstract: A steering system includes a mechanism configured to turn a steer wheel of a vehicle, a motor configured to generate driving force that is applied to the mechanism, and a controller configured to control the motor according to a steering status. The controller includes a limiting control circuit configured to limit a current that is supplied to the motor to a limiting value, a determining circuit configured to determine whether the steer wheel is in contact with an obstacle by using at least a comparison between a value of the current that is supplied to the motor and a threshold, and a threshold computing circuit configured to compute the threshold that is used by the determining circuit, the threshold computing circuit being configured to compute a value less than the limiting value according to the limiting value as the threshold.
    Type: Grant
    Filed: February 19, 2020
    Date of Patent: August 2, 2022
    Assignees: JTEKT CORPORATION, TOYOTA JIDOSHA KABUSHIKI KAISHA
    Inventors: Isao Namikawa, Koji Anraku, Yusuke Kakimoto, Yoshio Kudo
  • Publication number: 20220227412
    Abstract: In a steering system including a steering operation mechanism, a second actuator, a steering angle sensor, a steering torque sensor, and a steering operation control device and a control method for the steering system, only a drive assist target steered angle (first target steered angle) is reflected in a final target steered angle when a torque sensor value (actual steering torque) detected by the steering torque sensor is equal to or less than an intervention threshold. When the magnitude of the torque sensor value is more than the intervention threshold, the rate of reflection (distribution ratio) of a driver target steered angle (second target steered angle) in the final target steered angle is raised as the torque sensor value is increased, and the rate of reflection of the driver target steered angle in the final target steered angle is lowered as the magnitude of the torque sensor value is decreased.
    Type: Application
    Filed: November 30, 2021
    Publication date: July 21, 2022
    Applicants: TOYOTA JIDOSHA KABUSHIKI KAISHA, JTEKT Corporation
    Inventors: Kosuke Akatsuka, Yoshio Kudo, Rio Suda, Isao Namikawa, Takashi Kodera
  • Publication number: 20220185367
    Abstract: A steering control device includes a first calculator configured to calculate a first axial force, a second calculator, and a third calculator configured to calculate a third axial force. The third calculator is configured to, when a specific situation occurs in which a current of a turning motor has to be limited, decrease a reflection degree of the first axial force in the third axial force and increase a reflection degree of the second axial force in the third axial force.
    Type: Application
    Filed: December 9, 2021
    Publication date: June 16, 2022
    Applicants: JTEKT CORPORATION, TOYOTA JIDOSHA KABUSHIKI KAISHA
    Inventors: Isao NAMIKAWA, Satoshi MATSUDA, Tomoyuki IIDA, Masaharu YAMASHITA, Kenji SHIBATA
  • Publication number: 20220153346
    Abstract: An abnormality detection device includes a processing circuit configured to perform an abnormality detecting process. The abnormality detecting process includes a first state quantity acquiring process, a second state quantity acquiring process, a difference calculating process of calculating a difference between a first state quantity and a second state quantity, and a determination process of comparing an absolute value of the difference with a difference threshold value. The abnormality detecting process is a process of detecting an abnormality of a turning unit when the absolute value of the difference is greater than the difference threshold value, and the processing circuit is configured not to perform the determination process when an absolute value of an actual current value is greater than a current threshold value.
    Type: Application
    Filed: November 15, 2021
    Publication date: May 19, 2022
    Applicant: JTEKT CORPORATION
    Inventors: Koji ANRAKU, Isao NAMIKAWA, Takuji YOSHIDA
  • Publication number: 20220153343
    Abstract: A steer-by-wire steering system for a vehicle, including: an operating device including a steering operating member, a counterforce applying mechanism configured to apply, to the steering operating member, an operation counterforce by a counterforce motor, and an operating controller configured to control the operation counterforce; a steering device including a steering actuator configured to steer a wheel by a steering motor and a steering controller configured to control an amount of steering of the wheel by the steering actuator; and a communication line communicably connecting the operating controller and the steering controller, wherein the steering controller is configured to: determine a status code based on a status of the steering device; and transmit the status code to the operating controller via the communication line; and wherein the operating controller is configured to change a magnitude of the operation counterforce in accordance with the status code received by the operating controller.
    Type: Application
    Filed: November 4, 2021
    Publication date: May 19, 2022
    Applicants: Toyota Jidosha Kabushiki Kaisha, JTEKT CORPORATION
    Inventors: Tomoyuki IIDA, Masaharu Yamashita, Kenji Shibata, Yuji Fujita, Takashi Kodera, Isao Namikawa, Satoshi Matsuda
  • Patent number: 11325642
    Abstract: A steering apparatus includes: a mechanism that turns a turning wheel; a first motor that generates a driving force that is given to the mechanism; and a control device. The control device includes: a first computation circuit that computes a first limiting value to which an electric current to be supplied to the first motor is limited in a particular situation; a determination circuit that determines whether the turning wheel is in touch with an obstacle; a second computation circuit that computes a second limiting value to which the electric current to be supplied to the first motor is limited when the determination circuit determines that the turning wheel is in touch with the obstacle; and a third computation circuit that computes the threshold to be used by the determination circuit, based on a smaller limiting value of the first limiting value and the second limiting value.
    Type: Grant
    Filed: March 20, 2020
    Date of Patent: May 10, 2022
    Assignee: JTEKT CORPORATION
    Inventors: Isao Namikawa, Koji Anraku, Yusuke Kakimoto
  • Patent number: 11292510
    Abstract: A steering control device includes an electronic control unit. The electronic control unit controls operation of a steering-side motor so as to apply a steering reaction force that resists a steering operation input to the steering wheel. The electronic control unit computes an obstruction strike reaction force for regulating a steering operation that steers a steered wheel toward an obstruction. The electronic control unit generates determination information indicating that the steered wheel is struck by an obstruction. The determination information includes first determination information indicating that the left side of the steered wheel is struck by an obstruction, and second determination information indicating that the right side of the steered wheel is struck by an obstruction. The electronic control unit sets a direction in which the obstruction strike reaction force is applied based on the generated determination information.
    Type: Grant
    Filed: February 13, 2020
    Date of Patent: April 5, 2022
    Assignees: JTKEKT CORPORATION, TOYOTA JIDOSHA KABUSHIKI KAISHA
    Inventors: Koji Anraku, Isao Namikawa, Yusuke Kakimoto, Yoshio Kudo
  • Publication number: 20220089217
    Abstract: A steering control device includes a control unit configured to control at least an operation of a steering-side motor. The control unit is configured to calculate a target reaction torque; calculate a difference axial force that is used to limit steering for turning the turning wheels in a predetermined direction, the difference axial force being reflected in the target reaction torque; and set a reference angle to one of a steering angle and a turning angle, set a converted angle to an angle obtained by converting another of the steering angle and the turning angle according to a steering angle ratio, and calculate the difference axial force based on a difference between the reference angle and the converted angle.
    Type: Application
    Filed: September 22, 2021
    Publication date: March 24, 2022
    Applicants: JTEKT CORPORATION, TOYOTA JIDOSHA KABUSHIKI KAISHA
    Inventors: Isao NAMIKAWA, Satoshi MATSUDA, Tomoyuki IIDA, Yoshio KUDO, Masaharu YAMASHITA, Kenji SHIBATA
  • Publication number: 20220081027
    Abstract: A steering system to steer wheels by a movement of a steering shaft, including: the steering shaft; an electric motor; a converter configured to convert a rotational motion of the motor into the movement of the steering shaft; a motor rotation angle obtainer configured to obtain a motor rotation angle from a zero point position; a movement-amount-related-amount obtainer configured to obtain a movement-amount-related amount that is a movement amount of the steering shaft from a neutral position or a physical amount in a one-to-one correspondence with the movement amount; and a controller including a malfunction detector configured to detect a presence or absence of a malfunction of the converter in a mode that differs depending on a temperature state of the steering system, based on the motor rotation angle from the zero point position obtained by the motor rotation angle obtainer and the movement-amount-related amount obtained by the movement-amount-related-amount obtainer.
    Type: Application
    Filed: September 8, 2021
    Publication date: March 17, 2022
    Applicants: Toyota Jidosha Kabushiki Kaisha, Jtekt Corporation
    Inventors: Takuji Yoshida, Masahide Nitano, Isao Namikawa, Koji Anraku
  • Publication number: 20210323599
    Abstract: The steering control system of a steer-by-wire vehicle includes a turning angle calculation unit for calculating a target turning angle based on a steering angle of a steering wheel, and a reaction torque calculation unit for calculating a target reaction torque based on a state of the vehicle. When an alert request is issued, the reaction torque calculation unit calculates a basic reaction torque based on the steering angle, calculates an alert reaction torque for notifying a vehicle state, and calculates the target reaction torque obtained by summing the basic reaction torque and the alert reaction torque. In a process of calculating the target turning angle from the steering angle, the turning angle calculation unit calculates the target turning angle by excluding a steering angle or a turning angle corresponding to the alert reaction torque.
    Type: Application
    Filed: April 1, 2021
    Publication date: October 21, 2021
    Applicants: TOYOTA JIDOSHA KABUSHIKI KAISHA, JTEKT Corporation
    Inventors: Tetsuya MORINO, Yoshio KUDO, Isao NAMIKAWA, Takashi KODERA
  • Publication number: 20210309290
    Abstract: A steering control device includes control circuitry configured to perform synchronization control.
    Type: Application
    Filed: March 31, 2021
    Publication date: October 7, 2021
    Applicant: JTEKT CORPORATION
    Inventors: Yoshiyuki UCHINO, Yusuke KAKIMOTO, Koji ANRAKU, Isao NAMIKAWA, Kenji SHIBATA, Takafumi SATO
  • Publication number: 20210269086
    Abstract: A steering control apparatus is configured to control a steering system having a structure in which a power transmission path between a steering mechanism and a steering operation mechanism including a motor configured to generate a motor torque is separated. The steering control apparatus includes a controller configured to control driving of the motor. The controller detects an abnormality of the steering operation mechanism when a value indicating a variation in the motor torque is a value indicating a state in which a steering operation shaft is presumed to be immovable though the motor torque is applied.
    Type: Application
    Filed: February 22, 2021
    Publication date: September 2, 2021
    Applicant: JTEKT CORPORATION
    Inventors: Koji ANRAKU, Isao NAMIKAWA, Takuji YOSHIDA, Masahide NITANO
  • Publication number: 20200361517
    Abstract: A control device is configured to control a reaction motor based on a command value that is computed depending on a steering state. The control device includes a first computation circuit configured to compute a first shaft force, a second computation circuit configured to compute a second shaft force, and a third computation circuit configured to set a limit value that limits a variation range of the first shaft. The third computation circuit is configured to compute a final shaft force using the set limit value, through execution of a limiting process by which the first shaft force is limited, the final shaft force being reflected in the command value.
    Type: Application
    Filed: April 28, 2020
    Publication date: November 19, 2020
    Applicant: JTEKT CORPORATION
    Inventors: Isao NAMIKAWA, Koji ANRAKU
  • Publication number: 20200307681
    Abstract: A steering control device includes a processor. The processor is configured to calculate an axial force component corresponding to an axial force acting on a steered shaft that operates so as to steer a steered wheel. The processor is also configured to calculate a restriction reaction force, when a vehicle comes into a condition in which steering of the steered wheel in one direction is restricted. The processor is also configured to calculate target reaction torque based on a reaction force component obtained by adding the axial force component and the restriction reaction force. The processor is also configured to perform, in the calculation of the axial force component, a guard process that restrains the reaction force component from becoming too large.
    Type: Application
    Filed: March 26, 2020
    Publication date: October 1, 2020
    Applicant: JTEKT CORPORATION
    Inventors: Yusuke KAKIMOTO, Isao NAMIKAWA, Koji ANRAKU
  • Publication number: 20200307686
    Abstract: A steering apparatus includes: a mechanism that turns a turning wheel; a first motor that generates a driving force that is given to the mechanism; and a control device. The control device includes: a first computation circuit that computes a first limiting value to which an electric current to be supplied to the first motor is limited in a particular situation; a determination circuit that determines whether the turning wheel is in touch with an obstacle; a second computation circuit that computes a second limiting value to which the electric current to be supplied to the first motor is limited when the determination circuit determines that the turning wheel is in touch with the obstacle; and a third computation circuit that computes the threshold to be used by the determination circuit, based on a smaller limiting value of the first limiting value and the second limiting value.
    Type: Application
    Filed: March 20, 2020
    Publication date: October 1, 2020
    Applicant: JTEKT CORPORATION
    Inventors: Isao NAMIKAWA, Koji ANRAKU, Yusuke KAKIMOTO
  • Publication number: 20200307680
    Abstract: A steering control device includes a processor. The processor is configured to calculate an axial force component and a restriction reaction force. The processor is also configured to calculate target reaction torque based on a reaction force component obtained by adding the axial force component and the restriction reaction force. The processor is also configured to limit an absolute value of the reaction force component to a limit value or less, the limit value being such a value that the reaction force component does not become too large.
    Type: Application
    Filed: March 26, 2020
    Publication date: October 1, 2020
    Applicant: JTEKT CORPORATION
    Inventors: Yusuke KAKIMOTO, Isao NAMIKAWA, Koji ANRAKU
  • Publication number: 20200298908
    Abstract: A steering device includes: a mechanism configured to turn turning wheels of a vehicle; a motor configured to generate drive force that is applied to the mechanism; and a controller configured to control the motor in accordance with a steering state. The controller includes a determination circuit configured to determine whether or not one of the turning wheels is in contact with an obstacle based on at least a value of electric current that is supplied to the motor and a vehicle speed. The controller is configured to, when one of the turning wheels is in contact with the obstacle, notify a driver that one of the turning wheels is in contact with the obstacle.
    Type: Application
    Filed: March 17, 2020
    Publication date: September 24, 2020
    Applicants: JTEKT CORPORATION, TOYOTA JIDOSHA KABUSHIKI KAISHA
    Inventors: Isao NAMIKAWA, Koji ANRAKU, Yusuke KAKIMOTO, Yoshio KUDO
  • Publication number: 20200298901
    Abstract: In a controller for a steering device, the steering device includes a structure where motive power transmission between a steering unit and a turning unit is separated. The controller includes a control circuit configured to control operation of a steering-side motor that is provided in the steering unit to give steering reaction force that is force against the steering input into the steering unit. In a case where turning of the turning wheels to one direction is restricted, the control circuit is configured to calculate restriction reaction force for restricting steering that is to turn the turning wheels to the one direction. The control circuit is configured to calculate the restriction reaction force based on information on the steering unit.
    Type: Application
    Filed: March 17, 2020
    Publication date: September 24, 2020
    Applicants: JTEKT CORPORATION, TOYOTA JIDOSHA KABUSHIKI KAISHA
    Inventors: Koji ANRAKU, Isao NAMIKAWA, Yusuke KAKIMOTO, Yoshio KUDO, Tetsuya MORINO
  • Publication number: 20200283059
    Abstract: A steering control device for a steering system includes an electronic control unit configured to: calculate target torque that is a target value of the motor torque; control operation of the motor; calculate a vehicle speed basic axial force based on a detected vehicle speed; calculate another state quantity basic axial force based on a state quantity other than the detected vehicle speed; calculate a distributed axial force by adding the vehicle speed basic axial force and the other state quantity basic axial force at individually set distribution ratios; calculate the target torque based on the distributed axial force; and reduce the distribution ratio of the vehicle speed basic axial force when the detected vehicle speed is abnormal as compared to when the detected vehicle speed is normal.
    Type: Application
    Filed: February 26, 2020
    Publication date: September 10, 2020
    Applicants: JTEKT CORPORATION, TOYOTA JIDOSHA KABUSHIKI KAISHA
    Inventors: Takashi KODERA, Isao NAMIKAWA, Yusuke KAKIMOTO, Yoshio KUDO
  • Publication number: 20200269903
    Abstract: A steering control device includes an electronic control unit. The electronic control unit controls operation of a steering-side motor so as to apply a steering reaction force that resists a steering operation input to the steering wheel. The electronic control unit computes an obstruction strike reaction force for regulating a steering operation that steers a steered wheel toward an obstruction. The electronic control unit generates determination information indicating that the steered wheel is struck by an obstruction. The determination information includes first determination information indicating that the left side of the steered wheel is struck by an obstruction, and second determination information indicating that the right side of the steered wheel is struck by an obstruction. The electronic control unit sets a direction in which the obstruction strike reaction force is applied based on the generated determination information.
    Type: Application
    Filed: February 13, 2020
    Publication date: August 27, 2020
    Applicants: JTEKT CORPORATION, TOYOTA JIDOSHA KABUSHIKI KAISHA
    Inventors: Koji ANRAKU, Isao NAMIKAWA, Yusuke KAKIMOTO, Yoshio KUDO