Patents by Inventor Hideki Sawada

Hideki Sawada 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: 10778113
    Abstract: An intelligent power module includes at least one power semiconductor module including a semiconductor device, and a sealing body sealing an outer periphery of the semiconductor device, a driving circuit part mounted on the sealing body and configured to drive the power semiconductor module, and a cooling part on which the sealing body is mounted, and configured to cool the power semiconductor module.
    Type: Grant
    Filed: April 15, 2019
    Date of Patent: September 15, 2020
    Assignee: ROHM CO., LTD.
    Inventor: Hideki Sawada
  • Publication number: 20200269905
    Abstract: An electric power steering system is provided that is capable of performing assist control in which a change in a steering feel is reduced. The electric power steering system includes a current command value calculating unit configured to output a current command value Iref1 in accordance with steering torque and a vehicle speed on the basis of an assist map. The current command value calculating unit includes a vibration component reducing section configured to reduce a vibration component resulting from vibrations for warning that have been transmitted to a steering wheel and included in the steering torque.
    Type: Application
    Filed: June 7, 2019
    Publication date: August 27, 2020
    Applicant: NSK LTD.
    Inventors: Takayoshi SUGAWARA, Takuya MASUKO, Tomoki FUKUDA, Hideki SAWADA
  • Publication number: 20200254631
    Abstract: An abnormal condition determination system includes a detection device which detects rotation of each rotation shaft of a robot and an abnormal condition determination device which detects an encoder abnormal condition based on an absolute signal and an incremental signal from the detection device. The abnormal condition determination device calculates an absolute angle of the rotation shaft based on an amount of variation in angle of rotation of the rotation shaft indicated by an incremental signal from an incremental encoder. The abnormal condition determination device determines the detection device as abnormal when a difference between the absolute angle of the rotation shaft calculated based on the incremental signal and the absolute angle of the rotation shaft indicated by the absolute signal from an absolute encoder is out of an allowable range.
    Type: Application
    Filed: November 12, 2015
    Publication date: August 13, 2020
    Inventors: Hideki Sawada, Toshiyuki Sato, Tatsuo Onoyama, Ryoichi Okura, Mugen Kawazu
  • Publication number: 20200180682
    Abstract: A vector-control type motor control unit that calculates dq-axes control assist command values, calculates dq-axes current command values from the dq-axes control assist command values, converts the dq-axes current command values into 3-phase duty command values, and drives and controls a 3-phase brushless motor by an inverter of a PWM control, wherein a dead time compensation of the inverter is performed by calculating 3-phase dead time reference compensation values based on a motor rotational angle which is phase-corrected by using the dq-axes current command values, calculating dead time compensation values by processing the 3-phase dead time reference compensation values by a gain and a sign, and adding the dead time compensation values to dq-axes voltage command values or 3-phase voltage command values.
    Type: Application
    Filed: June 12, 2018
    Publication date: June 11, 2020
    Applicant: NSK Ltd.
    Inventors: Hiroaki TAKASE, Ryo MINAKI, Hideki SAWADA, Takayoshi SUGAWARA
  • Patent number: 10676127
    Abstract: An electric power steering apparatus of a vector control system that compensates a dead time of an inverter without tuning operation, improves a distortion of a current waveform and a responsibility of a current control, and suppresses a steering sound, a vibration and a ripple.
    Type: Grant
    Filed: July 20, 2017
    Date of Patent: June 9, 2020
    Assignee: NSK LTD.
    Inventors: Hiroaki Takase, Ryo Minaki, Hideki Sawada, Takayoshi Sugawara
  • Patent number: 10668941
    Abstract: An electric power steering apparatus compensates a dead time of an inverter without tuning operation, improves distortion of a current waveform and responsibility of a current control, and suppresses sound, vibration and ripple. The apparatus calculates dq-axes steering-assist command values based on at least a steering torque, calculates dq-axes current command values from the dq-axes steering-assist command values, converts the dq-axes current command values into 3-phase duty command values, driving-controls a 3-phase brushless motor by an inverter of a PWM control, and applies an assist torque to a steering system of a vehicle. Dead time reference compensation values are calculated based on a motor rotational angle. Dead time compensation of the inverter adds dead time compensation values in which the dead time reference compensation values are processed by using a gain, a sign and the like, to dq-axes voltage command values or to 3-phase voltage command values.
    Type: Grant
    Filed: July 14, 2017
    Date of Patent: June 2, 2020
    Assignee: NSK LTD.
    Inventors: Hiroaki Takase, Ryo Minaki, Hideki Sawada, Takayoshi Sugawara
  • Publication number: 20200130730
    Abstract: [Problem] An object of the present invention is to provide a vector control type motor control unit that compensates a dead time of an inverter without a tuning operation, improves a distortion of a current waveform and responsibility of the current control, and suppresses sound, vibration and a torque ripple.
    Type: Application
    Filed: June 12, 2018
    Publication date: April 30, 2020
    Applicant: NSK LTD.
    Inventors: Hiroaki TAKASE, Ryo MINAKI, Hideki SAWADA, Takayoshi SUGAWARA
  • Patent number: 10597071
    Abstract: An electric power steering apparatus of vector control system that calculates steering assist command values of dq axes based on at least a steering torque, calculates dq-axes current command values from the steering assist command values, converts the dq-axes current command values into 3-phase duty command values, driving-controls a 3-phase brushless motor by an inverter of a PWM control, and applies an assist torque to a steering system of a vehicle, wherein the electric power steering apparatus has plural dead time compensating functions of which efficiencies to respectively perform a dead time compensation of the inverter are different each other, and performs the dead time compensation by switching from one of the plural dead time compensating functions to an another dead time compensating function with a predetermined condition.
    Type: Grant
    Filed: August 16, 2017
    Date of Patent: March 24, 2020
    Assignee: NSK LTD.
    Inventors: Hiroaki Takase, Ryo Minaki, Hideki Sawada, Takayoshi Sugawara
  • Patent number: 10549772
    Abstract: A vector control type electric power steering apparatus that compensates a dead time of an inverter, a motor back-EMF and an interference voltage by means of a mutual inductance between motor windings, improves a distortion of a current waveform and a responsibility of a current control, and suppresses a noisy sound, vibration and a ripple. The apparatus driving-controls a three-phase brushless motor which applies an assist torque to a steering mechanism of a vehicle by using a current command value calculated based on at least a steering torque, and vector-controls the three-phase brushless motor by using dq-axis command values that are converted from the current command value via an inverter, including: a 3-phase disturbance observer to compensate respective phase disturbance voltages, which include a dead time of the inverter, for 3-phase voltage command values.
    Type: Grant
    Filed: July 14, 2017
    Date of Patent: February 4, 2020
    Assignee: NSK LTD.
    Inventors: Ryo Minaki, Hiroaki Takase, Hideki Sawada, Takayoshi Sugawara
  • Patent number: 10530245
    Abstract: [Problem] An object of the present invention is to provide an electric power steering apparatus of a vector control system that compensates a dead time of an inverter, a motor back-EMF and an interference voltage due to a mutual inductance between motor windings, improves a distortion of a current waveform and a responsibility of a current control, and suppresses a noise, vibration and a ripple.
    Type: Grant
    Filed: July 18, 2017
    Date of Patent: January 7, 2020
    Assignee: NSK LTD.
    Inventors: Ryo Minaki, Hiroaki Takase, Hideki Sawada, Takayoshi Sugawara
  • Publication number: 20190382048
    Abstract: An electric power steering apparatus that drives and controls a motor which applies an assist orque to a steering system of a vehicle and has a function switching between an assist mode and an automatic mode, including a torsion bar torsional angle calculating section to calculate a torsion bar torsional angle based on a torque information, an output-side column shaft relative angle generating section to output an output-side relative angle from an electrical angle signal of the motor, an actual handle angle calculating section to calculate an actual handle angle based on the torsion bar torsional angle and the output-side relative angle, a resonance filter to obtain an estimated handle angle in a hands-off state from the output-side relative angle, and a hands-on/off judging section to judge a hands-on state when a time that a deviation angle between the actual handle angle and the estimated handle angle is equal to or more than a predetermined angle is continued for the predetermined time or more.
    Type: Application
    Filed: February 19, 2018
    Publication date: December 19, 2019
    Applicant: NSK LTD.
    Inventors: Hideki SAWADA, Yukie FUJIWARA, Ryo MINAKI, Takayoshi SUGAWARA
  • Publication number: 20190375449
    Abstract: An electric power steering apparatus of a vector control system that drives and controls a motor by an inverter and applies an assist torque to a steering system of a vehicle, including the first compensation function to perform a dead time (DT) compensation based on respective phase motor terminal voltages and respective phase duty command values, the second compensation function to perform a DT compensation based on steering assist command values, the third compensation function to perform the DT compensation based on dq-axis current command values, and a temperature detecting section to detect temperature of ECU, wherein the correction of the DT compensation is performed based on the temperature, wherein switches of the compensation functions are performed by using a conditional branch due to software and a gradual-changing switch, wherein the dq-axis DT compensation values after the conditional branch and the gradual-changing switch are performed are calculated, and wherein the dq-axis voltage command val
    Type: Application
    Filed: February 13, 2018
    Publication date: December 12, 2019
    Applicant: NSK LTD.
    Inventors: Hiroaki TAKASE, Ryo MINAKI, Hideki SAWADA, Takayoshi SUGAWARA
  • Patent number: 10494016
    Abstract: An electric power steering apparatus that ideally compensates dead time of the inverter without the tuning operation, improves distortion of the current waveform and the responsibility of the current control, and suppresses sound, vibration, the ripple that the low speed steering maneuver is effective.
    Type: Grant
    Filed: July 20, 2017
    Date of Patent: December 3, 2019
    Assignee: NSK LTD.
    Inventors: Hiroaki Takase, Ryo Minaki, Hideki Sawada, Takayoshi Sugawara
  • Patent number: 10494017
    Abstract: An electric power steering apparatus of a vector control system converts calculated dq-axes current command values into 3-phase duty command values, driving-controls a 3-phase brushless motor by an inverter of a PWM control, and applies an assist torque to a steering system of a vehicle, wherein compensation signs of 3-phase current model command values in which the dq-axes current command values are converted into a 3-phase current command value model are estimated, wherein a dead time compensation amount is calculated based on an inverter-applying voltage, and wherein dead time compensation is performed by adding dead time compensation values that are 2-phase values converted from 3-phase values in which the compensation signs are multiplied with the dead time compensation amount, to dq-axes voltage command values, or by adding 3-phase dead time compensation values to 3-phase voltage command values.
    Type: Grant
    Filed: July 7, 2017
    Date of Patent: December 3, 2019
    Assignee: NSK LTD.
    Inventors: Hiroaki Takase, Ryo Minaki, Hideki Sawada, Takayoshi Sugawara
  • Publication number: 20190344824
    Abstract: An electric power steering apparatus of vector control system that calculates steering assist command values of dq axes based on at least a steering torque, calculates dq-axes current command values from the steering assist command values, converts the dq-axes current command values into 3-phase duty command values, driving-controls a 3-phase brushless motor by an inverter of a PWM control, and applies an assist torque to a steering system of a vehicle, wherein the electric power steering apparatus has plural dead time compensating functions of which efficiencies to respectively perform a dead time compensation of the inverter are different each other, and performs the dead time compensation by switching from one of the plural dead time compensating functions to an another dead time compensating function with a predetermined condition.
    Type: Application
    Filed: August 16, 2017
    Publication date: November 14, 2019
    Applicant: NSK Ltd.
    Inventors: Hiroaki TAKASE, Ryo MINAKI, Hideki SAWADA, Takayoshi SUGAWARA
  • Publication number: 20190337553
    Abstract: A vector control type electric power steering apparatus that compensates a dead time of an inverter, a motor back-EMF and an interference voltage by means of a mutual inductance between motor windings, improves a distortion of a current waveform and a responsibility of a current control, and suppresses a noisy sound, vibration and a ripple. The apparatus driving-controls a three-phase brushless motor which applies an assist torque to a steering mechanism of a vehicle by using a current command value calculated based on at least a steering torque, and vector-controls the three-phase brushless motor by using dq-axis command values that are converted from the current command value via an inverter, including: a 3-phase disturbance observer to compensate respective phase disturbance voltages, which include a dead time of the inverter, for 3-phase voltage command values.
    Type: Application
    Filed: July 14, 2017
    Publication date: November 7, 2019
    Applicant: NSK LTD.
    Inventors: Ryo MINAKI, Hiroaki TAKASE, Hideki SAWADA, Takayoshi SUGAWARA
  • Publication number: 20190329817
    Abstract: An electric power steering apparatus that ideally compensates dead time of the inverter without the tuning operation, improves distortion of the current waveform and the responsibility of the current control, and suppresses sound, vibration, the ripple that the low speed steering maneuver is effective.
    Type: Application
    Filed: July 20, 2017
    Publication date: October 31, 2019
    Applicant: NSK LTD.
    Inventors: Hiroaki TAKASE, Ryo MINAKI, Hideki SAWADA, Takayoshi SUGAWARA
  • Publication number: 20190322309
    Abstract: An electric power steering apparatus of a vector control system that compensates a dead time of an inverter without tuning operation, improves a distortion of a current waveform and a responsibility of a current control, and suppresses a sound, a vibration and a ripple.
    Type: Application
    Filed: July 14, 2017
    Publication date: October 24, 2019
    Applicant: NSK Ltd.
    Inventors: Hiroaki TAKASE, Ryo MINAKI, Hideki SAWADA, Takayoshi SUGAWARA
  • Patent number: D864132
    Type: Grant
    Filed: July 3, 2017
    Date of Patent: October 22, 2019
    Assignee: ROHM CO., LTD.
    Inventor: Hideki Sawada
  • Patent number: D875058
    Type: Grant
    Filed: August 29, 2019
    Date of Patent: February 11, 2020
    Assignee: ROHM CO., LTD.
    Inventor: Hideki Sawada