Patents by Inventor Naoto Sonoda

Naoto Sonoda 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: 20170212499
    Abstract: A servo control apparatus includes a sensor unit for detecting a motor speed; an amplifier for driving a motor and feeding back a current; a magnetic pole position detector; a position controller for outputting a speed command; a speed controller for outputting a current command; a current controller for outputting a voltage command; a speed estimator for calculating an estimated speed from the voltage command; a magnetic pole position estimator for calculating an estimated magnetic pole position from the estimated speed; a sensor malfunction detector; a stop position command generator; and a first switch for switching from the position command to the stop position command, a second switch for switching from the magnetic pole position to the estimated magnetic pole position, and a third switch for switching from the detected speed to the estimated speed, when the sensor malfunction detector has detected a malfunction.
    Type: Application
    Filed: April 10, 2017
    Publication date: July 27, 2017
    Applicant: Fanuc Corporation
    Inventors: Kouki Kameta, Naoto Sonoda
  • Patent number: 9709975
    Abstract: A control system of servo motors in a machine tool, comprising a host control device which generates position command values for processing a workpiece, servo control devices which drive servo motors to operate a tool for processing using the position command values, and position detectors which detect positions of the servo motors or a tool position and further a position error computing part computes position error between the position command values and detected positions of the servo motors, a reference angle generating part calculates a reference point on a closed figure and a reference angle which varies monotonously from a current processing point under the condition that any position inside of the closed figure which the position command value forms as the center, and learning control parts use the reference angle and the position error as the basis to perform angle synchronization type learning control to control the servo motors.
    Type: Grant
    Filed: July 24, 2015
    Date of Patent: July 18, 2017
    Assignee: FANUC CORPORATION
    Inventors: Naoto Sonoda, Yukio Toyozawa, Yasusuke Iwashita
  • Publication number: 20170075337
    Abstract: A control device for a machine tool for cutting a rotationally-symmetric workpiece by a tool, includes a machining command making unit for making a machining command for an auxiliary motor based on rotation speeds of the workpiece and the tool, and feed rates of the tool and the workpiece, an oscillation command making unit for making an oscillation command for the auxiliary motor, based on the rotation speeds and the feed rates, so that the oscillation command is asynchronous with the rotation speed of the workpiece around the axis of rotation, and so that the tool intermittently cuts the workpiece, an addition unit for adding the oscillation command to the machining command, and a control unit for controlling the auxiliary motor based on the machining command to which the oscillation command has been added.
    Type: Application
    Filed: September 15, 2016
    Publication date: March 16, 2017
    Applicant: FANUC CORPORATION
    Inventors: Kouki Kameta, Naoto Sonoda
  • Publication number: 20170031349
    Abstract: A servo control system for controlling a plurality of axes of a machine tool, comprises: a plurality of servo control units for controlling the plurality of axes, respectively; a plurality of learning control units that are provided one each in the plurality of servo control units, and each configured to control a cyclic operation highly precisely; a common learning memory for storing correction data which at least a portion of the plurality of learning control units generates; a memory allocation unit for allocating at least a portion of a memory area in the learning memory to the axis that the learning control unit that generated the correction data controls; and a memory amount notifying unit for notifying the memory allocation unit as to the amount of memory that each of the plurality of learning control units of the respective axes requires.
    Type: Application
    Filed: July 26, 2016
    Publication date: February 2, 2017
    Inventors: Kouki KAMETA, Naoto SONODA
  • Publication number: 20170004857
    Abstract: A servo control system according to the present invention includes a servo control device for driving a driven body that operates periodically using a servomotor; and a learning controller for generating correction data based on a location deviation with respect to a uniform command pattern, and storing the correction data in delay memory and correcting the location deviation. The delay memory includes first memory having a short access delay time and second memory having a long access delay time. The servo control device includes a switching unit for assigning one of the first memory and the second memory to the learning controller, depending on a learning period according to the command pattern.
    Type: Application
    Filed: June 28, 2016
    Publication date: January 5, 2017
    Inventors: Kouki KAMETA, Naoto SONODA
  • Patent number: 9523975
    Abstract: A servo controller includes: a first position feedback acquisition unit; a second position feedback acquisition unit; a converter converting the acquired position feedback of the first shaft to a value corresponding to the position feedback of the second shaft based on a synchronous ratio; a synchronous error calculator calculating synchronous error which is difference between the converted position feedback of the first shaft and the position feedback of the second shaft; a positional deviation calculator calculating a positional deviation of the second shaft which is difference between the position command for the second shaft and the position feedback of the second shaft; a filtering processor extracting components in a predetermined frequency range from the difference between the synchronous error and the positional deviation of the second shaft; and, a positional deviation corrector correcting the positional deviation of the second shaft by use of the output from the filtering processor.
    Type: Grant
    Filed: April 7, 2015
    Date of Patent: December 20, 2016
    Assignee: FANUC CORPORATION
    Inventor: Naoto Sonoda
  • Publication number: 20160334760
    Abstract: A servo control apparatus includes a sensor unit for detecting a motor speed; an amplifier for driving a motor and feeding back a current; a magnetic pole position detector; a position controller for outputting a speed command; a speed controller for outputting a current command; a current controller for outputting a voltage command; a speed estimator for calculating an estimated speed from the voltage command; a magnetic pole position estimator for calculating an estimated magnetic pole position from the estimated speed; a sensor malfunction detector; a stop position command generator; and a first switch for switching from the position command to the stop position command, a second switch for switching from the magnetic pole position to the estimated magnetic pole position, and a third switch for switching from the detected speed to the estimated speed, when the sensor malfunction detector has detected a malfunction.
    Type: Application
    Filed: May 4, 2016
    Publication date: November 17, 2016
    Applicant: FANUC CORPORATION
    Inventors: Kouki Kameta, Naoto Sonoda
  • Patent number: 9471055
    Abstract: A servo control device having a position control unit and a speed control unit to control a front end point of a machine of a machine tool, comprising: a position detecting unit for detecting a position of a motor; a first position error calculating unit for calculating a first position error based on a position command to a motor and position feedback from the position detecting unit; a torsion estimating unit for estimating an amount of torsion of the front end point of the machine; a second position error calculating unit for adding the first position error and estimated amount of torsion to calculate a second position error; a coefficient adapting unit for determining a coefficient of feedforward control so as to minimize the second position error; and a higher order feedforward control unit for performing feedforward control by using the determined coefficient and the position command.
    Type: Grant
    Filed: June 2, 2015
    Date of Patent: October 18, 2016
    Assignee: Fanuc Corporation
    Inventor: Naoto Sonoda
  • Publication number: 20160291573
    Abstract: A servo control apparatus for a machine that performs machining by causing a plurality of synchronizing axes to operate cooperatively in synchronized relationship with a reference axis, the servo control apparatus comprising: a position detection unit for detecting at least one of the position of the servo motor and the position of a driven body; a position error calculation unit for calculating an error between the position command and the position detected by the position detection unit; a reference axis position acquisition unit for acquiring the positions of a plurality of reference axes; a reference axis selection unit for selecting one reference axis based on a machining condition of the driven body from among the plurality of reference axes whose positions have been acquired; and a learning control unit for performing learning control using an angle synchronization method, based on the error and the position of the selected reference axis.
    Type: Application
    Filed: March 22, 2016
    Publication date: October 6, 2016
    Applicant: FANUC CORPORATION
    Inventors: Kouki Kameta, Naoto Sonoda
  • Patent number: 9367045
    Abstract: Servo control system includes a first repeat control unit for a first servo motor based on a reference angle and a first position error between a swing command and a position of the first servo motor, a multiplication unit which multiplies the swing command by a ratio according to a tilt angle of an inclined surface of a material to be ground to calculate a swing command after multiplication, and a second repeat control unit for a second servo motor based on a reference angle and second position error between the swing command after multiplication and a position of the second servo motor. The first and the second position error are respectively corrected, and driving of the first and the second servo motors are controlled based on the corrected first and second position error, thereby grinding the inclined surface of the material.
    Type: Grant
    Filed: November 28, 2014
    Date of Patent: June 14, 2016
    Assignee: FANUC CORPORATION
    Inventor: Naoto Sonoda
  • Patent number: 9331618
    Abstract: A magnetic pole position detector includes, a voltage command unit that generates high-frequency voltage command in a dq coordinate system, a three-phase transformation unit that transforms the high-frequency voltage command in the dq coordinate system to high-frequency voltage command in a three-phase coordinate system by using an estimated magnetic pole position, a current detection unit that detects three-phase current fed from a power converter for generating drive power, a dq transformation unit that transforms the detected three-phase current to current in the dq coordinate system by using the estimated magnetic pole position, an estimated magnetic pole position calculation unit that calculates a new estimated magnetic pole position to be used in three-phase dq transformations, and a magnetic pole position confirmation unit that confirms that, when converging on a certain position, the estimated magnetic pole position is the magnetic pole position at the time when the synchronous motor is started.
    Type: Grant
    Filed: November 25, 2013
    Date of Patent: May 3, 2016
    Assignee: Fanuc Corporation
    Inventors: Naoto Sonoda, Yukio Toyozawa
  • Patent number: 9304504
    Abstract: The servo controller of the present invention includes a first axis speed feedback obtaining unit, a second axis speed feedback obtaining unit configured to obtain an amount of speed feedback for a second axis synchronizing with a first axis, a speed conversion unit configured to convert an amount of speed feedback for the first axis by using a conversion coefficient, a speed difference calculating unit configured to calculate a speed difference between the converted amount of speed feedback for the first axis and the amount of speed feedback for the second axis, a torque correction calculating unit configured to calculate a torque correction value by using the speed difference, a second axis torque command correcting unit using the torque correction value, a torque correction value converting unit using the conversion coefficient, and a first axis torque command correcting unit using the converted torque correction value.
    Type: Grant
    Filed: March 19, 2015
    Date of Patent: April 5, 2016
    Assignee: FANUC CORPORATION
    Inventor: Naoto Sonoda
  • Patent number: 9285785
    Abstract: A frequency component extracting unit (15) extracts a frequency component included in a control signal at a first frequency step size. A frequency detection unit (16) detects, from the extracted frequency component, a frequency corresponding to a natural frequency of a target object constituted of a motor (3) and a driven member (4). A frequency step size setting unit (17) sets a second frequency step size smaller than the first frequency step size. A center frequency changing unit (18) increases or decreases a center frequency of a variable bandstop filter (13) at the second frequency step size in order to output a control signal after the variable bandstop filter (13) removes a frequency component corresponding to the natural frequency after the change from the control signal.
    Type: Grant
    Filed: May 8, 2014
    Date of Patent: March 15, 2016
    Assignee: FANUC CORPORATION
    Inventor: Naoto Sonoda
  • Publication number: 20160070097
    Abstract: A processing system comprising a laser beam source which generates a laser beam, a galvano scanner which comprises a mirror for reflecting the laser beam and a servo motor for rotating the mirror and which emits the laser beam to a workpiece, and an operation control device which controls the operation of the servo motor in accordance with a sinusoidal drive command.
    Type: Application
    Filed: August 31, 2015
    Publication date: March 10, 2016
    Applicant: FANUC CORPORATION
    Inventors: Naoto Sonoda, Yukio Toyozawa
  • Patent number: 9257923
    Abstract: A control system includes a current control unit providing, in accordance with the magnetic pole position of a rotor in which permanent magnets are disposed, a first current command to a first excitation phase of a stator winding and providing a second current command to a second excitation phase, a current error calculator calculating a current error which is a difference between a current flowing through the motor during the first period and the first current command or a difference between a current flowing through the motor during the second period and the second current command, and an abnormality detection and diagnosis unit detecting an abnormality based on the speed, the direction of movement and the amount of movement of the motor and the magnitude of the current error.
    Type: Grant
    Filed: March 13, 2014
    Date of Patent: February 9, 2016
    Assignee: FANUC CORPORATION
    Inventor: Naoto Sonoda
  • Publication number: 20160033954
    Abstract: A control system of servo motors in a machine tool, comprising a host control device which generates position command values for processing a workpiece, servo control devices which drive servo motors to operate a tool for processing using the position command values, and position detectors which detect positions of the servo motors or a tool position and further a position error computing part computes position error between the position command values and detected positions of the servo motors, a reference angle generating part calculates a reference point on a closed figure and a reference angle which varies monotonously from a current processing point under the condition that any position inside of the closed figure which the position command value forms as the center, and learning control parts use the reference angle and the position error as the basis to perform angle synchronization type learning control to control the servo motors.
    Type: Application
    Filed: July 24, 2015
    Publication date: February 4, 2016
    Inventors: Naoto Sonoda, Yukio Toyozawa, Yasusuke Iwashita
  • Publication number: 20150355628
    Abstract: A servo control device having a position control unit and a speed control unit to control a front end point of a machine of a machine tool, comprising: a position detecting unit for detecting a position of a motor; a first position error calculating unit for calculating a first position error based on a position command to a motor and position feedback from the position detecting unit; a torsion estimating unit for estimating an amount of torsion of the front end point of the machine; a second position error calculating unit for adding the first position error and estimated amount of torsion to calculate a second position error; a coefficient adapting unit for determining a coefficient of feedforward control so as to minimize the second position error; and a higher order feedforward control unit for performing feedforward control by using the determined coefficient and the position command.
    Type: Application
    Filed: June 2, 2015
    Publication date: December 10, 2015
    Applicant: FANUC CORPORATION
    Inventor: Naoto Sonoda
  • Patent number: 9166512
    Abstract: A motor control device for controlling a motor which drives a control target, includes: a speed feedback control unit which generates a pre-correction torque command for controlling such that an actual speed of the control target follows a speed command which is input; an inverse model calculation unit which calculates a coefficient of an inverse model with a transfer function inversed from a transfer function of the control target by using the speed command and the pre-correction torque command; a torque correction value generating unit which generates a torque correction value by using the speed command and the coefficient of the inverse model; and a torque command generating unit which generates a torque command for the motor which drives the control target by using the pre-correction torque command and torque correction value.
    Type: Grant
    Filed: July 3, 2014
    Date of Patent: October 20, 2015
    Assignee: FANUC CORPORATION
    Inventor: Naoto Sonoda
  • Publication number: 20150286197
    Abstract: A servo controller includes: a first position feedback acquisition unit; a second position feedback acquisition unit; a converter converting the acquired position feedback of the first shaft to a value corresponding to the position feedback of the second shaft based on a synchronous ratio; a synchronous error calculator calculating synchronous error which is difference between the converted position feedback of the first shaft and the position feedback of the second shaft; a positional deviation calculator calculating a positional deviation of the second shaft which is difference between the position command for the second shaft and the position feedback of the second shaft; a filtering processor extracting components in a predetermined frequency range from the difference between the synchronous error and the positional deviation of the second shaft; and, a positional deviation corrector correcting the positional deviation of the second shaft by use of the output from the filtering processor.
    Type: Application
    Filed: April 7, 2015
    Publication date: October 8, 2015
    Inventor: Naoto SONODA
  • Publication number: 20150268658
    Abstract: The servo controller of the present invention includes a first axis speed feedback obtaining unit, a second axis speed feedback obtaining unit configured to obtain an amount of speed feedback for a second axis synchronizing with a first axis, a speed conversion unit configured to convert an amount of speed feedback for the first axis by using a conversion coefficient, a speed difference calculating unit configured to calculate a speed difference between the converted amount of speed feedback for the first axis and the amount of speed feedback for the second axis, a torque correction calculating unit configured to calculate a torque correction value by using the speed difference, a second axis torque command correcting unit using the torque correction value, a torque correction value converting unit using the conversion coefficient, and a first axis torque command correcting unit using the converted torque correction value.
    Type: Application
    Filed: March 19, 2015
    Publication date: September 24, 2015
    Inventor: Naoto Sonoda