Patents by Inventor Atsuo Sakai

Atsuo Sakai 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: 11228273
    Abstract: A controller for a motor includes a first processing circuit and a second processing circuit configured to communicate with each other. The first processing circuit is configured to execute a first operation amount calculation process, an operation process, and an output process. The first operation amount calculation process is a process of calculating a first operation amount. The output process is a process of outputting the first operation amount to the second processing circuit. The second processing circuit is configured to execute a second operation amount calculation process, a first use operation process, a second use operation process, and an elimination process.
    Type: Grant
    Filed: March 2, 2020
    Date of Patent: January 18, 2022
    Assignees: JTEKT CORPORATION, TOYOTA JIDOSHA KABUSHIKI KAISHA
    Inventors: Takahiro Toko, Atsuo Sakai, Ryo Irie
  • Patent number: 11095247
    Abstract: A controller for a motor includes a first processing circuit and a second processing circuit. The first processing circuit is configured to execute a first operation amount calculation process, an operation process, and an output process. The first operation amount calculation process is a process of calculating a first operation amount. The operation process is a process of operating a first drive circuit. The second processing circuit is configured to execute a second operation amount calculation process, a first use operation process, a second use operation process, and an initial value setting process. The second operation amount calculation process is a process of calculating a second operation amount. The initial value setting process is a process of setting an initial value of an integral element depending on a value of an integral element of the first operation amount calculation process.
    Type: Grant
    Filed: February 26, 2020
    Date of Patent: August 17, 2021
    Assignee: DENSO CORPORATION
    Inventors: Takahiro Toko, Atsuo Sakai, Ryo Irie, Yoshihide Kuroda
  • Publication number: 20200295698
    Abstract: A controller for a motor includes a first processing circuit and a second processing circuit. The first processing circuit is configured to execute a first operation amount calculation process, an operation process, and an output process. The first operation amount calculation process is a process of calculating a first operation amount. The operation process is a process of operating a first drive circuit. The second processing circuit is configured to execute a second operation amount calculation process, a first use operation process, a second use operation process, and an initial value setting process. The second operation amount calculation process is a process of calculating a second operation amount. The initial value setting process is a process of setting an initial value of an integral element depending on a value of an integral element of the first operation amount calculation process.
    Type: Application
    Filed: February 26, 2020
    Publication date: September 17, 2020
    Applicants: JTEKT CORPORATION, DENSO CORPORATION
    Inventors: Takahiro TOKO, Atsuo SAKAI, Ryo IRIE, Yoshihide KURODA
  • Publication number: 20200295699
    Abstract: A controller for a motor includes a first processing circuit and a second processing circuit configured to communicate with each other. The first processing circuit is configured to execute a first operation amount calculation process, an operation process, and an output process. The first operation amount calculation process is a process of calculating a first operation amount. The output process is a process of outputting the first operation amount to the second processing circuit. The second processing circuit is configured to execute a second operation amount calculation process, a first use operation process, a second use operation process, and an elimination process.
    Type: Application
    Filed: March 2, 2020
    Publication date: September 17, 2020
    Applicants: JTEKT CORPORATION, TOYOTA JIDOSHA KABUSHIKI KAISHA
    Inventors: Takahiro TOKO, Atsuo SAKAI, Ryo IRIE
  • Patent number: 10266198
    Abstract: There is provided a motor control device capable of preventing occurrence of a difference in command value between control systems and reducing torque ripples and noise and vibration of a motor, unlike in a case where a motor is controlled by control systems that are independent from each other. In a motor control device, at least one of parameters for a first control system is shared by both of the systems, and a first control calculation circuit and a second control calculation circuit calculate the assist command values based on the parameter. Thus, motor drive circuits of the control systems drive motor coils based on the assist command values. Namely, when the steering torques and the vehicle speeds for the control systems are all normal, assist control circuits of the control systems calculate the assist command values based on the steering torque and the vehicle speed.
    Type: Grant
    Filed: August 4, 2017
    Date of Patent: April 23, 2019
    Assignee: JTEKT CORPORATION
    Inventors: Yuji Fujita, Hiroshi Kawamura, Atsuo Sakai
  • Patent number: 9988078
    Abstract: A steering control apparatus is provided which allows mitigation of an adverse effect of a technique for fixing a regulation member to a vehicle body on a phenomenon resulting from execution of steering operation control on steered wheels. An axial-force acquisition processing circuit calculates a rack axial force based on currents iu, iv, and iw flowing through a steering operation motor. A correction processing circuit corrects a target steered angle based on the rack axial force to obtain a target steered angle. A steered angle control processing circuit calculates a torque command value as the amount of operation for adjusting a steered angle to the target steered angle through feedback control. An operation signal generation processing circuit controllably adjusts a torque of a steering operation motor to the torque command value.
    Type: Grant
    Filed: October 7, 2016
    Date of Patent: June 5, 2018
    Assignee: JTEKT CORPORATION
    Inventor: Atsuo Sakai
  • Publication number: 20180043928
    Abstract: There is provided a motor control device capable of preventing occurrence of a difference in command value between control systems and reducing torque ripples and noise and vibration of a motor, unlike in a case where a motor is controlled by control systems that are independent from each other. In a motor control device, at least one of parameters for a first control system is shared by both of the systems, and a first control calculation circuit and a second control calculation circuit calculate the assist command values based on the parameter. Thus, motor drive circuits of the control systems drive motor coils based on the assist command values. Namely, when the steering torques and the vehicle speeds for the control systems are all normal, assist control circuits of the control systems calculate the assist command values based on the steering torque and the vehicle speed.
    Type: Application
    Filed: August 4, 2017
    Publication date: February 15, 2018
    Applicant: JTEKT CORPORATION
    Inventors: Yuji FUJITA, Hiroshi KAWAMURA, Atsuo SAKAI
  • Publication number: 20180037254
    Abstract: A vehicle steering system includes a clutch provided on a power transmission path extending from a steering wheel to steered wheels, a reactive-force motor connected to a first portion of the power transmission path, which is closer to the steering wheel than the clutch is, a steering motor including a first motor coil and a second motor coil, and connected to a second portion of the power transmission path, which is closer to the steered wheels than the clutch is, a driving circuit configured to supply electric power to the reactive-force motor, a first driving circuit configured to supply electric power to the first motor coil, and a second driving circuit configured to supply electric power to the second motor coil.
    Type: Application
    Filed: July 27, 2017
    Publication date: February 8, 2018
    Applicant: JTEKT CORPORATION
    Inventors: Keisuke IZUTANI, Masahiko SAKAMAKI, Hiroaki KAJI, Tomonari YAMAKAWA, Atsuo SAKAI, Tomoyasu KADA
  • Publication number: 20170106900
    Abstract: A steering control apparatus is provided which allows mitigation of an adverse effect of a technique for fixing a regulation member to a vehicle body on a phenomenon resulting from execution of steering operation control on steered wheels. An axial-force acquisition processing circuit calculates a rack axial force based on currents iu, iv, and iw flowing through a steering operation motor. A correction processing circuit corrects a target steered angle based on the rack axial force to obtain a target steered angle. A steered angle control processing circuit calculates a torque command value as the amount of operation for adjusting a steered angle to the target steered angle through feedback control. An operation signal generation processing circuit controllably adjusts a torque of a steering operation motor to the torque command value.
    Type: Application
    Filed: October 7, 2016
    Publication date: April 20, 2017
    Applicant: JTEKT CORPORATION
    Inventor: Atsuo SAKAI
  • Patent number: 9043089
    Abstract: There is provided an actuator control apparatus configured such that even when an electronic device that generates an electric signal to be used to control an actuator is provided in the form of a duplexed system, an increase in the number of communication paths between the electronic device and a controller is suppressed. A torque sensor and a rotation angle sensor are each provided in the form of a duplexed system. Two sets of a torque sensor and a rotation angle sensor are connected to a microcomputer via a SPI communication line. The torque sensors and the rotation angle sensors are connected to the microcomputer via CS communication lines, respectively. By selecting a communication target via a corresponding one of the CS communication lines, the microcomputer is able to receive multiple kinds of electric signals via each one of the SPI communication lines.
    Type: Grant
    Filed: May 29, 2014
    Date of Patent: May 26, 2015
    Assignee: JTEKT CORPORATION
    Inventors: Kazuya Sakai, Tsutomu Matsumoto, Atsuo Sakai, Kenichi Kozuka, Takehide Adachi
  • Publication number: 20140358375
    Abstract: There is provided an actuator control apparatus configured such that even when an electronic device that generates an electric signal to be used to control an actuator is provided in the form of a duplexed system, an increase in the number of communication paths between the electronic device and a controller is suppressed. A torque sensor and a rotation angle sensor are each provided in the form of a duplexed system. Two sets of a torque sensor and a rotation angle sensor are connected to a microcomputer via a SPI communication line. The torque sensors and the rotation angle sensors are connected to the microcomputer via CS communication lines, respectively. By selecting a communication target via a corresponding one of the CS communication lines, the microcomputer is able to receive multiple kinds of electric signals via each one of the SPI communication lines.
    Type: Application
    Filed: May 29, 2014
    Publication date: December 4, 2014
    Applicant: JTEKT CORPORATION
    Inventors: Kazuya SAKAI, Tsutomu MATSUMOTO, Atsuo SAKAI, Kenichi KOZUKA, Takehide ADACHI
  • Patent number: 8890459
    Abstract: A motor control device with which both high-accuracy current detection and improvement in voltage utilization factor are achieved is provided. When an ON time of any one of low potential side switching elements corresponding to respective phases in a driving circuit is shorter than a detection time of a current value, a microcomputer estimates a phase current value of a current undetectable phase based on current values of two phases other than the current undetectable phase corresponding to the said FET. Then, at the time of current detection using the blind correction, during current detection for two phases, other than the current undetectable phase, based on which the blind correction is performed, motor control signals for maintaining switching states of a switching arm corresponding to the current undetectable phase are output.
    Type: Grant
    Filed: March 10, 2010
    Date of Patent: November 18, 2014
    Assignee: JTEKT Corporation
    Inventors: Atsuo Sakai, Tsutomu Matsumoto, Kazushi Suzuki
  • Patent number: 8294407
    Abstract: A motor controller and an electric power steering system including the motor controller are provided. The motor controller has a microcomputer. When the on time of one of the lower potential-side FETs corresponding to the respective phases in a drive circuit becomes shorter than the detection time for detecting the phase current value, the microcomputer estimates the phase current value of the electric current undetectable phase based on the phase current values of the two phases other than the electric current undetectable phase corresponding to the relevant FET (blind estimation). When electric current detection is performed in the blind estimation, motor control signals are output, by which the switching state of the switching arm of the electric current undetectable phase is maintained and the power loss caused by the switching operation of the FETs in the two phases other than the electric current undetectable phase is compensated for.
    Type: Grant
    Filed: July 1, 2010
    Date of Patent: October 23, 2012
    Assignee: JTEKT Corporation
    Inventors: Satoru Mikamo, Atsuo Sakai
  • Patent number: 8217600
    Abstract: A motor control device is configured in such a manner that a current detection circuit and an exciting circuit for a motor resolver share one grounding wire. A microcomputer that serves as a current detector sets a phase of an exciting current in such a manner that values of an excitation noise superimposed on an output voltage of the current detection circuit at respective timings (L1, H1, L2, H2, . . . ), at which the output voltage is acquired in one current detection process, are equal to each other. An electric power steering system is provided with the motor control device.
    Type: Grant
    Filed: September 7, 2010
    Date of Patent: July 10, 2012
    Assignee: JTEKT Corporation
    Inventor: Atsuo Sakai
  • Publication number: 20120118662
    Abstract: A motor control device with which both high-accuracy current detection and improvement in voltage utilization factor are achieved is provided. When an ON time of any one of low potential side switching elements corresponding to respective phases in a driving circuit is shorter than a detection time of a current value, a microcomputer estimates a phase current value of a current undetectable phase based on current values of two phases other than the current undetectable phase corresponding to the said FET. Then, at the time of current detection using the blind correction, during current detection for two phases, other than the current undetectable phase, based on which the blind correction is performed, motor control signals for maintaining switching states of a switching arm corresponding to the current undetectable phase are output.
    Type: Application
    Filed: March 10, 2010
    Publication date: May 17, 2012
    Applicant: JTEKT CORPORATION
    Inventors: Atsuo Sakai, Tsutomu Matsumoto, Kazushi Suzuki
  • Publication number: 20110205672
    Abstract: A microcomputer detects and determines whether a problem exists in a power supply breaker of an ECU functioning as a motor controller. Specifically, the microcomputer determines whether there is a malfunction caused by a short circuit in a first FET based on the output voltage and output voltage that are detected in a first FET and a second FET, respectively, when the switching states of the first and second FETs are both off. Afterwards, the microcomputer determines whether there is a malfunction caused by a break in the first FET based on the output voltages of the first and second FETs that are detected when only the first FET is switched on. If the microcomputer determines that the first FET is free from any malfunction, the microcomputer determines whether there is a malfunction caused by a short circuit or a break in the second FET by comparing the output voltage of the first FET and a charge voltage of a smoothing capacitor that are detected afterwards.
    Type: Application
    Filed: September 14, 2009
    Publication date: August 25, 2011
    Applicant: JTEKT CORPORATION
    Inventor: Atsuo Sakai
  • Patent number: 7969107
    Abstract: A microcomputer compares a low voltage LV and a middle voltage MV to a predetermined voltage Vth set at a value in the vicinity of the grounded voltage (0 V) on the basis of detected phase voltages Vu, Vv and Vw, and thus, detects a break in a power supply line.
    Type: Grant
    Filed: October 5, 2007
    Date of Patent: June 28, 2011
    Assignee: JTEKT Corporation
    Inventor: Atsuo Sakai
  • Patent number: 7913805
    Abstract: A rotational angle sensor used in an electric power steering apparatus detects a rotational angle of a motor shaft at a portion on a steering system side, as a motor rotational angle (?m). A MPU sets a base correction amount (???m) based on a q-axis actual current value (Iq). The MPU sets a rotational angle correction amount (??m) used to correct the motor rotational angle (?m) by decreasing the base correction amount (???m) as a rotational angular speed (?) increases and by increasing the base correction amount (???m) as a torque differential value (dT/dt) increases.
    Type: Grant
    Filed: January 15, 2010
    Date of Patent: March 29, 2011
    Assignee: JTEKT Corporation
    Inventors: Akihiro Tomita, Atsuo Sakai, Satoru Mikamo
  • Publication number: 20110062905
    Abstract: A motor control device is configured in such a manner that a current detection circuit and an exciting circuit for a motor resolver share one grounding wire. A microcomputer that serves as a current detector sets a phase of an exciting current in such a manner that values of an excitation noise superimposed on an output voltage of the current detection circuit at respective timings (L1, H1, L2, H2, . . . ), at which the output voltage is acquired in one current detection process, are equal to each other. An electric power steering system is provided with the motor control device.
    Type: Application
    Filed: September 7, 2010
    Publication date: March 17, 2011
    Applicant: JTEKT CORPORATION
    Inventor: Atsuo SAKAI
  • Publication number: 20110005855
    Abstract: A motor controller and an electric power steering system including the motor controller are provided. The motor controller has a microcomputer. When the on time of one of the lower potential-side FETs corresponding to the respective phases in a drive circuit becomes shorter than the detection time for detecting the phase current value, the microcomputer estimates the phase current value of the electric current undetectable phase based on the phase current values of the two phases other than the electric current undetectable phase corresponding to the relevant FET (blind estimation). When electric current detection is performed in the blind estimation, motor control signals are output, by which the switching state of the switching arm of the electric current undetectable phase is maintained and the power loss caused by the switching operation of the FETs in the two phases other than the electric current undetectable phase is compensated for.
    Type: Application
    Filed: July 1, 2010
    Publication date: January 13, 2011
    Applicant: JTEKT CORPORATION
    Inventors: Satoru MIKAMO, Atsuo Sakai