Patents by Inventor Hirozumi Eki

Hirozumi Eki 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: 9914473
    Abstract: Provided is an electric power steering system that achieves a more appropriate steering feel. An ECU of the electric power steering system calculates a basic assist component and a target pinion angle based on at least steering torque. The ECU calculates a correction component for the basic assist component through feedback control in which an actual pinion angle is caused to match the target pinion angle. The ECU calculates an assist command value by adding the correction component to the basic assist component. The ECU corrects a hysteresis controlled variable and a viscosity component according to the rate of change (gradient) in a spring component with respect to a change in absolute value of the target pinion angle. Specifically, the ECU multiplies the hysteresis controlled variable and the viscosity component by gains that have a larger value as the rate of change in spring component increases.
    Type: Grant
    Filed: January 28, 2016
    Date of Patent: March 13, 2018
    Assignee: JTEKT CORPORATION
    Inventors: Terutaka Tamaizumi, Hirozumi Eki, Masayuki Kita
  • Patent number: 9718492
    Abstract: An end determination unit determines that a steering apparatus is in an end touching state when an angle deviation, which is a difference between an actual turning angle and a target turning angle, exceeds a threshold. This angle deviation exceeds the threshold before a large axial force is generated in a steering shaft. Accordingly, is it possible to determine that the steering apparatus is in the end touching state more quickly.
    Type: Grant
    Filed: February 10, 2014
    Date of Patent: August 1, 2017
    Assignee: JTEKT CORPORATION
    Inventors: Terutaka Tamaizumi, Hirozumi Eki, Masayuki Kita, Isao Namikawa
  • Patent number: 9573616
    Abstract: A control device in an electric power steering device calculates a first assist component based on steering torque and a vehicle speed. The control device also calculates a compensation component associated with an reverse input and calculates a steered angle command value based on an addition value of the compensation component and basic drive torque that is an addition value of the steering torque and the first assist component, produces a second assist component by performing steered angle feedback control that causes the steered angle of a vehicle to follow the steered angle command value. The control device controls drive of a motor based on an assist command value that is an addition value of the first assist component and the second assist component.
    Type: Grant
    Filed: February 27, 2015
    Date of Patent: February 21, 2017
    Assignee: JTEKT CORPORATION
    Inventors: Terutaka Tamaizumi, Hirozumi Eki, Masayuki Kita, Isao Namikawa, Akihiko Nishimura, Jun Hasegawa
  • Publication number: 20160229446
    Abstract: Provided is an electric power steering system that achieves a more appropriate steering feel. An ECU of the electric power steering system calculates a basic assist component and a target pinion angle based on at least steering torque. The ECU calculates a correction component for the basic assist component through feedback control in which an actual pinion angle is caused to match the target pinion angle. The ECU calculates an assist command value by adding the correction component to the basic assist component. The ECU corrects a hysteresis controlled variable and a viscosity component according to the rate of change (gradient) in a spring component with respect to a change in absolute value of the target pinion angle. Specifically, the ECU multiplies the hysteresis controlled variable and the viscosity component by gains that have a larger value as the rate of change in spring component increases.
    Type: Application
    Filed: January 28, 2016
    Publication date: August 11, 2016
    Applicant: JTEKT CORPORATION
    Inventors: Terutaka TAMAIZUMI, Hirozumi EKI, Masayuki KITA
  • Patent number: 9327760
    Abstract: There is provided an electric power steering system that makes it possible to improve the driver's steering feel, and that includes a controller that controls driving of a motor. The controller computes a first assist component based on a steering torque. The controller computes a torque command value based on a basic drive torque that is the sum of the steering torque and the first assist component, and computes an assist compensation component through feedback control based on the torque command value. The controller computes a steered angle command value based on a value obtained by adding the assist compensation component to the basic drive torque, and computes a second assist component through feedback control based on the steered angle command value. The controller controls driving of the motor based on an assist command value that is the sum of the first assist component and the second assist component.
    Type: Grant
    Filed: May 7, 2014
    Date of Patent: May 3, 2016
    Assignee: JTEKT CORPORATION
    Inventors: Terutaka Tamaizumi, Hirozumi Eki, Masayuki Kita, Isao Namikawa, Jun Hasegawa, Akihiko Nishimura
  • Patent number: 9296415
    Abstract: When only one of sensor signals generated by the plural systems and output from a torque sensor is normal, a control variable restriction processing part performs an assist restricting process for setting an upper limit value and a lower limit value of a basic assist control variable in accordance with at least one of the lateral acceleration, the steering angle, the steering speed, or the yaw rate.
    Type: Grant
    Filed: June 12, 2012
    Date of Patent: March 29, 2016
    Assignee: JTEKT CORPORATION
    Inventors: Hidenori Itamoto, Hirozumi Eki, Gempei Nakasone
  • Patent number: 9290200
    Abstract: In the vehicle power steering system, a first assist torque component is computed based on a steering torque and a vehicle speed. A target steered angle is computed based on the first assist torque component and the steering torque, and a second assist torque component is set based on the target steered angle and an actual steered angle. Then, the vehicle power steering system assists a steering operation by applying an assist torque Tas corresponding to the first assist torque component and the second assist torque component. Further, an ideal steered angle at which a vehicle is able to keep travelling in a lane is set based on image information on the lane captured by a camera, and a correction value is computed based on the deviation between the ideal steered angle and the actual steered angle. Then, the target steered angle is corrected by the correction value.
    Type: Grant
    Filed: August 8, 2014
    Date of Patent: March 22, 2016
    Assignee: JTEKT CORPORATION
    Inventors: Terutaka Tamaizumi, Hirozumi Eki, Masayuki Kita, Isao Namikawa
  • Patent number: 9272730
    Abstract: In an electric power steering system, a vehicle reactive force model computes a correction spring reactive torque in such a manner that an elasticity component included in a steering reactive force is increased with an increase in a lateral acceleration. As the lateral acceleration increases, an increase in a basic drive torque is suppressed by a larger amount. By an amount by which the magnitude of the basic drive torque is suppressed, a target pinion angle computed by a target pinion angle computing unit decreases and a correction component for a basic assist component is decreased. A steering assist force is decreased, and a steering reactive force is increased with a decrease in the steering assist force. Thus, it is possible to obtain an appropriate steering reactive force based on the magnitude of the lateral acceleration.
    Type: Grant
    Filed: August 19, 2014
    Date of Patent: March 1, 2016
    Assignee: JTEKT CORPORATION
    Inventors: Terutaka Tamaizumi, Masayuki Kita, Isao Namikawa, Hirozumi Eki
  • Publication number: 20150251691
    Abstract: A control device in an electric power steering device calculates a first assist component based on steering torque and a vehicle speed. The control device also calculates a compensation component associated with an reverse input and calculates a steered angle command value based on an addition value of the compensation component and basic drive torque that is an addition value of the steering torque and the first assist component, produces a second assist component by performing steered angle feedback control that causes the steered angle of a vehicle to follow the steered angle command value. The control device controls drive of a motor based on an assist command value that is an addition value of the first assist component and the second assist component.
    Type: Application
    Filed: February 27, 2015
    Publication date: September 10, 2015
    Inventors: Terutaka TAMAIZUMI, Hirozumi EKI, Masayuki KITA, Isao NAMIKAWA, Akihiko NISHIMURA, Jun HASEGAWA
  • Patent number: 9051004
    Abstract: A controller of an electric power steering system includes: a basic assist component computing unit (60) that computes a first assist component (Ta1*) based on a steering torque (Th); a steered angle command value computing unit (61) that computes a steered angle command value (?t*) based on the sum of the steering torque (Th) and the first assist component (Ta1*); and a steered angle feedback controller (62) that computes a second assist component (Ta2*) through feedback control on an actual steered angle (?t). The controller further includes: a correction component computing unit (65) that computes a correction component (Tc*) based on a steering angle (?s); and an assist command value computing unit (50) that computes an assist command value (Ta*) by subtracting the correction component (Tc*) from the sum of the first assist component (Ta1*) and the second assist component (Ta2*).
    Type: Grant
    Filed: August 19, 2014
    Date of Patent: June 9, 2015
    Assignee: JTEKT CORPORATION
    Inventors: Terutaka Tamaizumi, Masayuki Kita, Isao Namikawa, Hirozumi Eki
  • Patent number: 9045157
    Abstract: A zero point change model executes banked road correspondence control when a vehicle travels on a banked road. By this control, a target turning angle when the total torque is zero can be changed from a neutral turning angle to a lower side of an inclined road surface. Thus, a steering angle of a steering wheel according to a banked road can be realized even if the driver does not apply steering torque during traveling on a banked road. Accordingly, the driver can obtain a suitable steering feeling when traveling on a banked road while achieving the target turning angle according to the total torque.
    Type: Grant
    Filed: February 10, 2014
    Date of Patent: June 2, 2015
    Assignee: JTEKT CORPORATION
    Inventors: Terutaka Tamaizumi, Hirozumi Eki, Masayuki Kita, Isao Namikawa
  • Patent number: 8989966
    Abstract: An ECU controls the operation of an EPS actuator in order to periodically apply instantaneous motor torque to a steering system when assist continuation control is executed using a sensor signal (residual sensor signal) that is output by a sensor element in which an abnormality has not been detected, regardless of the application of an assist force. The ECU also detects an abnormality in the residual sensor signal based on whether the application of instantaneous motor torque is reflected in the residual sensor signal, which is the basis of the assist continuation control.
    Type: Grant
    Filed: February 10, 2012
    Date of Patent: March 24, 2015
    Assignee: JTEKT Corporation
    Inventors: Hidenori Itamoto, Akira Ito, Hirozumi Eki, Gempei Nakasone
  • Patent number: 8981690
    Abstract: An electric power steering system includes short-circuit determination means for determining whether a short-circuit between an energization failure phase and one of the two phases other than the energization failure phase has occurred while assist force is being generated using the two phases other than the energization failure phase as energization phases. When the short-circuit determination means determines that the short-circuit has occurred, generation of the assist force is stopped.
    Type: Grant
    Filed: September 4, 2012
    Date of Patent: March 17, 2015
    Assignee: JTEKT Corporation
    Inventors: Hidenori Itamoto, Hirozumi Eki, Gempei Nakasone
  • Patent number: 8977437
    Abstract: A target pinion angle computation unit computes a target pinion angle on the basis of a basic assist component and a steering torque, and computes the target pinion angle so as to rapidly increase a steering reaction force when it is determined based on the target pinion angle that a rack shaft of a rack-and-pinion mechanism reaches a position near a limit of a movable range of the rack shaft. In an EPS, a correction component for the basic assist component, which is necessary to increase the steering reaction force rapidly, is computed through execution of PID control for causing an actual pinion angle to coincide with the target pinion angle. Because the correction component is added to the basic assist component, the steering reaction force is increased rapidly when the rack shaft reaches the position near the limit of the movable range.
    Type: Grant
    Filed: September 11, 2013
    Date of Patent: March 10, 2015
    Assignee: JTEKT Corporation
    Inventors: Terutaka Tamaizumi, Hirozumi Eki, Masayuki Kita, Isao Namikawa
  • Publication number: 20150057889
    Abstract: In the vehicle power steering system, a first assist torque component is computed based on a steering torque and a vehicle speed. A target steered angle is computed based on the first assist torque component and the steering torque, and a second assist torque component is set based on the target steered angle and an actual steered angle. Then, the vehicle power steering system assists a steering operation by applying an assist torque Tas corresponding to the first assist torque component and the second assist torque component. Further, an ideal steered angle at which a vehicle is able to keep travelling in a lane is set based on image information on the lane captured by a camera, and a correction value is computed based on the deviation between the ideal steered angle and the actual steered angle. Then, the target steered angle is corrected by the correction value.
    Type: Application
    Filed: August 8, 2014
    Publication date: February 26, 2015
    Inventors: Terutaka TAMAIZUMI, Hirozumi EKI, Masayuki KITA, Isao NAMIKAWA
  • Publication number: 20150057890
    Abstract: In an electric power steering system, a vehicle reactive force model computes a correction spring reactive torque in such a manner that an elasticity component included in a steering reactive force is increased with an increase in a lateral acceleration. As the lateral acceleration increases, an increase in a basic drive torque is suppressed by a larger amount. By an amount by which the magnitude of the basic drive torque is suppressed, a target pinion angle computed by a target pinion angle computing unit decreases and a correction component for a basic assist component is decreased. A steering assist force is decreased, and a steering reactive force is increased with a decrease in the steering assist force. Thus, it is possible to obtain an appropriate steering reactive force based on the magnitude of the lateral acceleration.
    Type: Application
    Filed: August 19, 2014
    Publication date: February 26, 2015
    Inventors: Terutaka TAMAIZUMI, Masayuki KITA, Isao NAMIKAWA, Hirozumi EKI
  • Publication number: 20150057892
    Abstract: A controller of an electric power steering system includes: a basic assist component computing unit (60) that computes a first assist component (Ta1*) based on a steering torque (Th); a steered angle command value computing unit (61) that computes a steered angle command value (?t*) based on the sum of the steering torque (Th) and the first assist component (Ta1*); and a steered angle feedback controller (62) that computes a second assist component (Ta2*) through feedback control on an actual steered angle (?t). The controller further includes: a correction component computing unit (65) that computes a correction component (Tc*) based on a steering angle (?s); and an assist command value computing unit (50) that computes an assist command value (Ta*) by subtracting the correction component (Tc*) from the sum of the first assist component (Ta1*) and the second assist component (Ta2*).
    Type: Application
    Filed: August 19, 2014
    Publication date: February 26, 2015
    Inventors: Terutaka TAMAIZUMI, Masayuki KITA, Isao NAMIKAWA, Hirozumi EKI
  • Patent number: 8897965
    Abstract: An assisting command value calculating unit calculates a first assisting factor on the basis of the value of a torque differential control volume added to a basic assist control volume based on a steering torque value, while increasing or decreasing, on the basis of an assisting gradient, the torque differential control volume based on a torque differential value. The pinion angle F/B control unit calculates a pinion angle command value, capable of being converted to a steering angle of the steering wheel, on the basis of the steering torque and the first assisting factor, and executes rotational angle feedback control. The assisting command value calculating unit calculates an assisting command value on the basis of the value of a second assisting factor, calculated by the pinion angle F/B control unit, added to the first assisting factor.
    Type: Grant
    Filed: March 28, 2012
    Date of Patent: November 25, 2014
    Assignee: JTEKT Corporation
    Inventors: Terutaka Tamaizumi, Hirozumi Eki, Masayuki Kita, Isao Namikawa
  • Publication number: 20140343794
    Abstract: There is provided an electric power steering system that makes it possible to improve the driver's steering feel, and that includes a controller that controls driving of a motor. The controller computes a first assist component based on a steering torque. The controller computes a torque command value based on a basic drive torque that is the sum of the steering torque and the first assist component, and computes an assist compensation component through feedback control based on the torque command value. The controller computes a steered angle command value based on a value obtained by adding the assist compensation component to the basic drive torque, and computes a second assist component through feedback control based on the steered angle command value. The controller controls driving of the motor based on an assist command value that is the sum of the first assist component and the second assist component.
    Type: Application
    Filed: May 7, 2014
    Publication date: November 20, 2014
    Applicant: JTEKT CORPORATION
    Inventors: Terutaka TAMAIZUMI, Hirozumi EKI, Masayuki KITA, Isao NAMIKAWA, Jun HASEGAWA, Akihiko NISHIMURA
  • Publication number: 20140238769
    Abstract: A zero point change model executes banked road correspondence control when a vehicle travels on a banked road. By this control, a target turning angle when the total torque is zero can be changed from a neutral turning angle to a lower side of an inclined road surface. Thus, a steering angle of a steering wheel according to a banked road can be realized even if the driver does not apply steering torque during traveling on a banked road. Accordingly, the driver can obtain a suitable steering feeling when traveling on a banked road while achieving the target turning angle according to the total torque.
    Type: Application
    Filed: February 10, 2014
    Publication date: August 28, 2014
    Applicant: Jtekt Corporation
    Inventors: Terutaka TAMAIZUMI, Hirozumi EKI, Masayuki KITA, Isao NAMIKAWA