Patents by Inventor Hiroshi Sumasu

Hiroshi Sumasu 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).

  • Publication number: 20180241302
    Abstract: When supply of electric power to an inverter using a normally-ON switching element is abnormally stopped, a flow of a current to the switching element of the inverter is reduced. An inverter circuit includes an inverter having at least one arm including two normally-ON switching elements connected in series between two lines to which a voltage of a power supply is applied, a smoothing capacitor connected between the two lines at a position between the power supply and the inverter, and a normally-OFF relay connected into the first line out of the two lines at a position between the smoothing capacitor and the inverter.
    Type: Application
    Filed: February 8, 2018
    Publication date: August 23, 2018
    Applicant: JTEKT CORPORATION
    Inventors: Koichiro MATSUHISA, Hiroshi SUMASU
  • Patent number: 9991839
    Abstract: A maximum spectrum peak reduction unit sets a PWM count generated by a PWM duty ratio calculation unit for a specific current control period as PWM counts for respective PWM periods within the current control period, and changes the set PWM counts for the respective PWM periods within the current control period so that a frequency component having a frequency obtained by dividing a carrier frequency in half or less is included in a PWM signal waveform within the current control period without changing a total value of the PWM counts for the respective PWM periods.
    Type: Grant
    Filed: September 6, 2017
    Date of Patent: June 5, 2018
    Assignee: JTEKT CORPORATION
    Inventor: Hiroshi Sumasu
  • Publication number: 20180091080
    Abstract: A microcomputer includes a current command value setting unit configured to set a two-phase current command value in a two-phase rotating coordinate system for each of PWM cycles in a current control cycle, and an open-loop control unit configured to calculate a two-phase voltage command value for each of the PWM cycles, according to a motor voltage equation, based on the two-phase current command value for each of the PWM cycles that is set by the current command value setting unit and a rotation speed of an electric motor. The two-phase voltage command value is a command value of voltage that is to be applied to the electric motor.
    Type: Application
    Filed: September 13, 2017
    Publication date: March 29, 2018
    Applicant: JTEKT CORPORATION
    Inventor: Hiroshi SUMASU
  • Publication number: 20180083564
    Abstract: A maximum spectrum peak reduction unit sets a PWM count generated by a PWM duty ratio calculation unit for a specific current control period as PWM counts for respective PWM periods within the current control period, and changes the set PWM counts for the respective PWM periods within the current control period so that a frequency component having a frequency obtained by dividing a carrier frequency in half or less is included in a PWM signal waveform within the current control period without changing a total value of the PWM counts for the respective PWM periods.
    Type: Application
    Filed: September 6, 2017
    Publication date: March 22, 2018
    Applicant: JTEKT CORPORATION
    Inventor: Hiroshi SUMASU
  • Patent number: 9726725
    Abstract: A power circuit abnormality detection method for a power circuit detects whether an abnormality in a power source relay exists. The power circuit includes a pre-charge circuit opening and closing a connection between a direct current power source and a smoothing condenser by bypassing the power source relay to pre-charge the smoothing condenser, and a discharge circuit connected in parallel to the smoothing condenser to discharge electric charges stored in the smoothing condenser via a discharge resistance when a discharge switch is closed. The power circuit abnormality detection method includes a step of detecting whether the open contact abnormality in the power source relay exists based on whether a charge voltage of the smoothing condenser is reduced when a predetermined period of time has elapsed since both the discharge circuit and the power source relay are closed after the pre-charge circuit is opened.
    Type: Grant
    Filed: July 29, 2014
    Date of Patent: August 8, 2017
    Assignee: JTEKT CORPORATION
    Inventors: Mayuko Wakida, Yuta Iwai, Hiroshi Sumasu, Kohji Kimura
  • Publication number: 20150035539
    Abstract: A power circuit abnormality detection method for a power circuit detects whether an abnormality in a power source relay exists. The power circuit includes a pre-charge circuit opening and closing a connection between a direct current power source and a smoothing condenser by bypassing the power source relay to pre-charge the smoothing condenser, and a discharge circuit connected in parallel to the smoothing condenser to discharge electric charges stored in the smoothing condenser via a discharge resistance when a discharge switch is closed. The power circuit abnormality detection method includes a step of detecting whether the open contact abnormality in the power source relay exists based on whether a charge voltage of the smoothing condenser is reduced when a predetermined period of time has elapsed since both the discharge circuit and the power source relay are closed after the pre-charge circuit is opened.
    Type: Application
    Filed: July 29, 2014
    Publication date: February 5, 2015
    Applicant: JTEKT CORPORATION
    Inventors: Mayuko Wakida, Yuta Iwai, Hiroshi Sumasu, Kohji Kimura
  • Patent number: 8736208
    Abstract: When one of six FETs has short-circuit faulted, a controllable region identification unit stops driving of an electric motor, and then performs processes for determining whether a short-circuit fault has occurred, and when a short-circuit fault has occurred, for identifying the position of the FET that has short-circuit faulted based on phase voltages (induced voltages) VU, VV, and VW of phases. When the position of the FET that has short-circuit faulted is identified, the controllable region identification unit performs a controllable region identification process. In detail, the controllable region identification unit identifies a “possible region,” an “indeterminate region,” and a “impossible region” based on phase voltages VU, VV, and VW of the phases.
    Type: Grant
    Filed: March 25, 2011
    Date of Patent: May 27, 2014
    Assignee: Jtekt Corporation
    Inventors: Shigekazu Okumura, Fumihiko Satou, Hiroshi Sumasu
  • Patent number: 8541965
    Abstract: A command current setting portion has a target value corrector that calculates d-axis and q-axis current command values idc, iqc that are to be supplied to an open-loop controller, based on d-axis and q-axis current target values id*, iq*. When d-axis and q-axis voltage target value vd*, vq* calculated from the d-axis and q-axis current target values id*, iq* by the motor circuit equations exceed a voltage limit, this target value corrector 26 corrects the d-axis and q-axis current target values id*, iq* by the field weakening control such that d-axis and q-axis voltages vd, vq and d-axis and q-axis currents id, iq satisfy ?(vd2+vq2)?Vlim and ?(id2+iq2)?Ilim respectively. The d-axis and q-axis current command values idc, iqc are obtained by this correction.
    Type: Grant
    Filed: March 30, 2009
    Date of Patent: September 24, 2013
    Assignee: JTEKT Corporation
    Inventors: Takeshi Ueda, Yuji Kariatsumari, Shigeki Nagase, Noboru Niguchi, Hiroshi Sumasu
  • Patent number: 8415565
    Abstract: A multilayer circuit substrate includes: a laminated circuit portion in which conductive layers and resin insulating layers are alternately laminated; and a metal substrate portion, wherein the laminated circuit portion is fixed to the metal substrate portion so that at least part of a lower surface of the laminated circuit portion is in contact with at least part of an upper surface of the metal substrate portion. An electronic component is mounted on the metal substrate portion.
    Type: Grant
    Filed: September 10, 2009
    Date of Patent: April 9, 2013
    Assignee: JTEKT Corporation
    Inventors: Shigeki Nagase, Motoo Nakai, Kouya Yoshida, Hiroshi Sumasu, Nobuhiro Uchida
  • Patent number: 8368343
    Abstract: A motor control device of the present invention includes: target electric current value setting units (15 and 16) that set target electric current values that should be supplied to a motor (1), basic voltage value computing units (511, 521, 51a, and 52a) that compute basic voltage values for driving the motor, a rotation angle speed computing unit (23) that computes a rotation angle speed of the motor, correction value computing units (50, 512, 515, 516, 522, 525, and 526) that compute correction values for correcting the basic voltage values based on motor electric current values and a rotation angle speed of the motor, correcting units (513 and 523) that obtain voltage command values by correcting the basic voltage values by the correction values computed by the correction value computing units, and a driving unit (13) that drives the motor by using voltage command values.
    Type: Grant
    Filed: February 18, 2009
    Date of Patent: February 5, 2013
    Assignee: JTEKT Corporation
    Inventors: Shigeki Nagase, Takeshi Ueda, Yuji Kariatsumari, Hiroshi Sumasu
  • Patent number: 8364349
    Abstract: An angle calculator determines an angle of a rotor. An angular speed calculator determines an angular speed of the rotor. A command current calculator determines a command current defined on a dq-axis. An open loop controller determines a command voltage defined on the dq-axis in accordance with a circuit equation of a motor, based on the command current and the angular speed. A dq-axis/three-phase converter converts the command voltage into a three-phase command voltage. A resistance calculator and a ?-value calculator respectively determines circuit resistance including armature winding resistance and a number of armature winding linkages which are included in the circuit equation of the motor, based on temperature of the motor detected by a temperature sensor and with reference to a table or the like which is stored in advance.
    Type: Grant
    Filed: January 6, 2009
    Date of Patent: January 29, 2013
    Assignee: JTEKT Corporation
    Inventors: Takeshi Ueda, Shigeki Nagase, Hiroshi Sumasu
  • Publication number: 20120326644
    Abstract: When one of six FETs has short-circuit faulted, a controllable region identification unit stops driving of an electric motor, and then performs processes for determining whether a short-circuit fault has occurred, and when a short-circuit fault has occurred, for identifying the position of the FET that has short-circuit faulted based on phase voltages (induced voltages) VU, VV, and VW of phases. When the position of the FET that has short-circuit faulted is identified, the controllable region identification unit performs a controllable region identification process. In detail, the controllable region identification unit identifies a “possible region,” an “indeterminate region,” and a “impossible region” based on phase voltages VU, VV, and VW of the phases.
    Type: Application
    Filed: March 25, 2011
    Publication date: December 27, 2012
    Applicant: JTEKT CORPORATION
    Inventors: Shigekazu Okumura, Fumihiko Satou, Hiroshi Sumasu
  • Patent number: 8288658
    Abstract: A multilayer circuit board in which wirings are arranged so that the inductance thereof is reduced. A ground wiring and a power source wiring which are provided in a multilayer circuit board are arranged so that most of the wirings are superposed vertically along a direction of a longer side of the circuit board, and since currents flow in an opposite direction to each other in the portions which are superposed, magnetic fields generated by the currents so flowing are canceled by each other. Similarly, a W-phase wiring, a V-phase wiring and a W-phase wiring are also arranged so that the wirings are partially superposed along their longer side direction vertically, and magnetic fields generated by currents flowing in the portions which are superposed vertically are canceled by one another. By this, the inductance of the wirings can be reduced by increasing a mutual inductance between these wirings.
    Type: Grant
    Filed: February 5, 2009
    Date of Patent: October 16, 2012
    Assignee: JTEKT Corporation
    Inventors: Nobuhiro Uchida, Motoo Nakai, Hiroshi Sumasu
  • Patent number: 7889978
    Abstract: An angle computing section determines an angle of a rotor, and an angular velocity computing section determines angular velocity of the rotor. A command current computing section determines, from a steering torque and vehicle velocity, command currents and taken along d-q axes. An open loop control section determines, from command currents and angular velocity, command voltages taken along the d-q axes in accordance with motor circuit equations. A d-q axis/three-phase conversion section converts the command voltages into command voltages of three phases. A ? computing section determines the number of armature winding flux linkages included in a motor circuit equation from a q-axis command voltage, the current value detected by a current sensor, and the angular velocity. Circuit resistance including armature winding resistance R included in the motor circuit equation may also be determined by means of the same configuration.
    Type: Grant
    Filed: January 31, 2008
    Date of Patent: February 15, 2011
    Assignee: JTEKT Corporation
    Inventors: Takeshi Ueda, Shigeki Nagase, Hiroshi Sumasu
  • Publication number: 20110025238
    Abstract: A command current setting portion has a target value corrector that calculates d-axis and q-axis current command values idc, iqc that are to be supplied to an open-loop controller, based on d-axis and q-axis current target values id*, iq*. When d-axis and q-axis voltage target value vd*, vq* calculated from the d-axis and q-axis current target values id*, iq* by the motor circuit equations exceed a voltage limit, this target value corrector 26 corrects the d-axis and q-axis current target values id*, iq* by the field weakening control such that d-axis and q-axis voltages vd, vq and d-axis and q-axis currents id, iq satisfy ?(vd2+vq2)?Vlim and ?(id2+iq2)?Ilim respectively. The d-axis and q-axis current command values idc, iqc are obtained by this correction.
    Type: Application
    Filed: March 30, 2009
    Publication date: February 3, 2011
    Applicant: JTEKT CORPORATION
    Inventors: Takeshi Ueda, Yuji Kariatsumari, Shigeki Nagase, Noboru Niguchi, Hiroshi Sumasu
  • Publication number: 20110018487
    Abstract: A motor control device of the present invention includes: target electric current value setting units (15 and 16) that set target electric current values that should be supplied to a motor (1), basic voltage value computing units (511, 521, 51a, and 52a) that compute basic voltage values for driving the motor, a rotation angle speed computing unit (23) that computes a rotation angle speed of the motor, correction value computing units (50, 512, 515, 516, 522, 525, and 526) that compute correction values for correcting the basic voltage values based on motor electric current values and a rotation angle speed of the motor, correcting units (513 and 523) that obtain voltage command values by correcting the basic voltage values by the correction values computed by the correction value computing units, and a driving unit (13) that drives the motor by using voltage command values.
    Type: Application
    Filed: February 18, 2009
    Publication date: January 27, 2011
    Applicant: JTEKT Corporation
    Inventors: Shigeki Nagase, Takeshi Ueda, Yuji Kariatsumari, Hiroshi Sumasu
  • Publication number: 20110011633
    Abstract: A multilayer circuit board in which wirings are arranged so that the inductance thereof is reduced. A ground wiring and a power source wiring which are provided in a multilayer circuit board are arranged so that most of the wirings are superposed vertically along a direction of a longer side of the circuit board, and since currents flow in an opposite direction to each other in the portions which are superposed, magnetic fields generated by the currents so flowing are canceled by each other. Similarly, a W-phase wiring, a V-phase wiring and a W-phase wiring are also arranged so that the wirings are partially superposed along their longer side direction vertically, and magnetic fields generated by currents flowing in the portions which are superposed vertically are canceled by one another. By this, the inductance of the wirings can be reduced by increasing a mutual inductance between these wirings.
    Type: Application
    Filed: February 5, 2009
    Publication date: January 20, 2011
    Applicant: JTEKT CORPORATION
    Inventors: Nobuhiro Uchida, Motoo Nakai, Hiroshi Sumasu
  • Publication number: 20100280714
    Abstract: An angle calculator determines an angle of a rotor. An angular speed calculator determines an angular speed of the rotor. A command current calculator determines a command current defined on a dq-axis. An open loop controller determines a command voltage defined on the dq-axis in accordance with a circuit equation of a motor, based on the command current and the angular speed. A dq-axis/three-phase converter converts the command voltage into a three-phase command voltage. A resistance calculator and a ?-value calculator respectively determines circuit resistance including armature winding resistance and a number of armature winding linkages which are included in the circuit equation of the motor, based on temperature of the motor detected by a temperature sensor and with reference to a table or the like which is stored in advance.
    Type: Application
    Filed: January 6, 2009
    Publication date: November 4, 2010
    Applicant: JTEKT CORPORATION
    Inventors: Takeshi Ueda, Shigeki Nagase, Hiroshi Sumasu
  • Patent number: 7737648
    Abstract: A motor controller stores values corresponding to predetermined equivalent resistance which corresponds to power loss generated by switching on and off switching elements. Voltage command values are determined by adding voltage drop values determined from values corresponding to the equivalent resistance and values of current flowing in the switching elements to target applied voltage values corresponding to current command values which correspond to target output of a motor. The switching elements arranged in a power supply line to the motor are switched on and off by control signals generated according to the voltage command values.
    Type: Grant
    Filed: February 1, 2008
    Date of Patent: June 15, 2010
    Assignee: JTEKT Corporation
    Inventors: Shigeki Nagase, Hiroshi Sumasu, Takeshi Ueda
  • Publication number: 20100065307
    Abstract: A multilayer circuit substrate includes: a laminated circuit portion in which conductive layers and resin insulating layers are alternately laminated; and a metal substrate portion, wherein the laminated circuit portion is fixed to the metal substrate portion so that at least part of a lower surface of the laminated circuit portion is in contact with at least part of an upper surface of the metal substrate portion. An electronic component is mounted on the metal substrate portion.
    Type: Application
    Filed: September 10, 2009
    Publication date: March 18, 2010
    Applicant: JTEKT CORPORATION
    Inventors: Shigeki Nagase, Motoo Nakai, Kouya Yoshida, Hiroshi Sumasu, Nobuhiro Uchida