Patents by Inventor Tadashi Okita

Tadashi Okita 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: 10090789
    Abstract: To provide a motor control device capable of causing a motor to rotate in any rotation direction, even when leaving the connection state of the motor of a machine tool as standard.
    Type: Grant
    Filed: July 24, 2017
    Date of Patent: October 2, 2018
    Assignee: FANUC CORPORATION
    Inventors: Tadashi Okita, Yuuki Morita, Daisuke Tajima
  • Publication number: 20180259930
    Abstract: An object is to provide the numerical control device of a machine tool which can achieve both a reduction in heat generation and stability in heavy cutting. A numerical control device includes a command transmission portion which transmits a speed command value and a magnetic flux command value to the spindle control portion of a machine tool and a storage portion which stores magnetic flux amounts corresponding to tools that may be used in the machine tool. The numerical control device also includes a tool detection portion which detects a tool selected in the machine tool and a magnetic flux amount setting portion which commands the command transmission portion to read, from the storage portion, a magnetic flux amount corresponding to the tool detected by the tool detection portion and to output the magnetic flux amount to the spindle control portion of the machine tool.
    Type: Application
    Filed: March 7, 2018
    Publication date: September 13, 2018
    Applicant: FANUC CORPORATION
    Inventors: Kouki OIKAWA, Yuuki MORITA, Tadashi OKITA
  • Patent number: 10065255
    Abstract: A controller for controlling a synchronized operation of spindle and feed axes. A spindle-axis control section includes an initial-motion control section for making a spindle axis perform an accelerated rotation at maximum capacity from a process start position; a maximum-acceleration detecting section for detecting a maximum acceleration of the spindle axis; a residual rotation-amount detecting section for detecting a residual rotation amount of the spindle axis; a current-speed detecting section for detecting a current speed of the spindle axis; a positioning-motion control section for making the spindle axis perform a decelerated rotation so as to reach the target thread depth after the accelerated rotation; and an overshoot detecting section for detecting an overshoot of the spindle axis during the decelerated rotation.
    Type: Grant
    Filed: July 22, 2016
    Date of Patent: September 4, 2018
    Assignee: FANUC CORPORATION
    Inventors: Yuuki Morita, Tadashi Okita, Daisuke Tajima
  • Publication number: 20180239328
    Abstract: A numerical controller for controlling a machine tool including a spindle motor formed of an induction motor includes: a storage unit that stores a maximum acceleration at which the spindle motor can operate when a magnetic flux amount of the spindle motor reaches its maximum; a magnetic flux amount acquisition unit that acquires a present magnetic flux amount of the spindle motor; and an acceleration change unit that changes an acceleration of a position command based on a maximum acceleration of the spindle motor stored in the storage unit according to a magnetic flux amount at the start of movement of the spindle motor acquired by the magnetic flux amount acquisition unit when the spindle motor is operated by position control using a position command.
    Type: Application
    Filed: February 13, 2018
    Publication date: August 23, 2018
    Inventors: Kouki OIKAWA, Yuuki MORITA, Tadashi OKITA
  • Publication number: 20180239339
    Abstract: To reliably collect measured data without requiring a large-capacity storage device. A data collection device which is connected with a plurality of machine tools via a network includes: a priority calculation means for calculating a degree of relative priority for each of the plurality of machines tools, based on information related to a state of each of the machine tools; and a measured data collection means for deciding, in a case of receiving a collection request of measured data for the machine tool, which machine tool among the machine tools corresponding to the collection request to set as a collection target of the measured data based on the degree of relative priority, and for collecting the measured data from the machine tool decided as the collection target via the network.
    Type: Application
    Filed: January 31, 2018
    Publication date: August 23, 2018
    Inventors: Keitarou INAGAKI, Junichi TEZUKA, Tadashi OKITA
  • Patent number: 10048672
    Abstract: To provide a motor control device that prevents from becoming excessive correction, upon adding a backlash correction amount to a position command for a motor.
    Type: Grant
    Filed: September 29, 2017
    Date of Patent: August 14, 2018
    Assignee: FANUC CORPORATION
    Inventors: Shoutarou Hashimoto, Tadashi Okita, Yuuki Morita
  • Publication number: 20180224827
    Abstract: To provide a monitoring device, a machine tool, and a monitoring system capable of collecting data efficiently required for examining an alarm. A monitoring device is connected to multiple machine tools through a network. The monitoring device comprises: a monitoring unit that monitors the occurrence of an alarm in the machine tools; an acquisition unit that acquires a set of measurement target data items responsive to an alarm from a database on the occurrence of the alarm; and a collection unit that sets the set of measurement target data items in the multiple machine tools, and collects data measured by following the setting.
    Type: Application
    Filed: February 2, 2018
    Publication date: August 9, 2018
    Inventors: Kazuyuki SUGIYAMA, Junichi TEZUKA, Tadashi OKITA
  • Publication number: 20180210417
    Abstract: A controller controlling a synchronized operation of spindle and feed axes. The controller is configured to make a spindle axis perform an accelerated rotation at maximum capacity from a starting position aiming at a maximum rotation speed; detect a maximum acceleration of the spindle axis; detect a residual rotation amount of the spindle axis; detect a current speed of the spindle axis; and execute a position control for making the spindle axis perform a decelerated rotation so as to reach a target position, after the accelerated rotation at maximum capacity. The controller is further configured to make the spindle axis perform the decelerated rotation at a positioning deceleration higher than a deceleration corresponding to the maximum acceleration and equal to or lower than a maximum deceleration capable of compensating for a mechanical loss in a drive source during the decelerated rotation of the spindle axis.
    Type: Application
    Filed: January 24, 2018
    Publication date: July 26, 2018
    Inventors: Tadashi OKITA, Yuuki MORITA, Daisuke TAJIMA
  • Patent number: 10012974
    Abstract: A motor control system which makes a tool motor and a workpiece motor rotate in synchronization in a machine tool equipped with a tool motor, a workpiece motor, and a tool shaft movement motor which drives a linear shaft to change an intershaft distance between the tool shaft and the workpiece shaft, wherein when the power outage detector detects a power outage of the power supply during synchronous rotation of the tool motor and the workpiece motor, the operation of the forced deceleration circuit for causing forced deceleration of either one of the tool motor and workpiece motor is made to be delayed by a predetermined time and during that time the tool shaft movement motor is used to drive the linear shaft and separate the tool and workpiece as a retraction operation to thereby prevent damage to the tool and the workpiece at the time of a power outage.
    Type: Grant
    Filed: June 9, 2015
    Date of Patent: July 3, 2018
    Assignee: FANUC CORPORATION
    Inventors: Shoutarou Hashimoto, Tadashi Okita
  • Patent number: 10005165
    Abstract: A controller for controlling a synchronized operation of spindle and feed axes. A spindle-axis control section includes an initial-motion control section for making a spindle axis perform an accelerated rotation at maximum capacity from a process start position; a maximum-acceleration detecting section for detecting a maximum acceleration of the spindle axis; a residual rotation-amount detecting section for detecting a residual rotation amount of the spindle axis; a current-speed detecting section for detecting a current speed of the spindle axis; a decelerating-motion control section for making the spindle axis perform a decelerated rotation at a gradually increasing deceleration so as to reach an intermediate rotation speed after the accelerated rotation; and a positioning-motion control section for making the spindle axis perform a decelerated rotation at maximum capacity so as to reach the target thread depth after reaching the intermediate rotation speed.
    Type: Grant
    Filed: June 3, 2016
    Date of Patent: June 26, 2018
    Assignee: FANUC CORPORATION
    Inventors: Yuuki Morita, Daisuke Tajima, Tadashi Okita
  • Publication number: 20180136630
    Abstract: A controller controlling a synchronized operation of spindle and feed axes. A positioning-motion control section of a spindle-axis control section calculates a first velocity command making a spindle axis perform a decelerated rotation at a variable deceleration lower than a maximum deceleration during an acceleration-varying time just after the spindle axis reaches an intermediate speed or just before the spindle axis reaches a target position, and making the spindle axis perform the decelerated rotation at the maximum deceleration during a time except for the acceleration-varying time; calculates a second velocity command making the spindle axis perform a decelerated rotation at a constant deceleration lower than the maximum deceleration after the spindle axis reaches the intermediate speed; and chooses either one, achieving a lower speed, of the first and second velocity command during a period when the spindle axis operates from the intermediate speed to reach the target position.
    Type: Application
    Filed: November 15, 2017
    Publication date: May 17, 2018
    Inventors: Daisuke TAJIMA, Yuuki MORITA, Tadashi OKITA
  • Publication number: 20180117724
    Abstract: A controller of a machine tool capable of suppressing heat generation and realizing a stable cutting operation during deep cutting is provided. A numerical controller for controlling a machine tool including a spindle motor formed of an induction motor and a feed axis driving motor includes: a magnetic flux amount acquisition means that acquires a present magnetic flux amount of the spindle motor; and a speed change means that changes a speed of the feed axis driving motor on the basis of the magnetic flux amount.
    Type: Application
    Filed: October 25, 2017
    Publication date: May 3, 2018
    Applicant: FANUC CORPORATION
    Inventors: Yuuki MORITA, Tadashi OKITA
  • Patent number: 9958857
    Abstract: To provide a motor control device, motor control method, and non-transitory computer readable medium recording a motor control program, which add a backlash correction amount to a position command for a motor at the appropriate timing. Included are a first position detection part that detects a first position which is a position of a movable part; a second position detection part that detects a second position which is a position of a driven part; a positional error calculation part that calculates positional error, which is deviation between a converted first position detected value and a second position detected value; and a backlash correction part that adds a backlash correction amount when the absolute value for the variation of the positional error since reversal of a position command was detected exceeds the predetermined reference value.
    Type: Grant
    Filed: April 10, 2017
    Date of Patent: May 1, 2018
    Assignee: FANUC CORPORATION
    Inventors: Shoutarou Hashimoto, Tadashi Okita, Yuuki Morita
  • Publication number: 20180095446
    Abstract: To provide a motor control device that prevents from becoming excessive correction, upon adding a backlash correction amount to a position command for a motor.
    Type: Application
    Filed: September 29, 2017
    Publication date: April 5, 2018
    Inventors: Shoutarou HASHIMOTO, Tadashi OKITA, Yuuki MORITA
  • Patent number: 9910426
    Abstract: A controller for controlling a synchronized operation of spindle and feed axes. A spindle-axis control section includes a section for making a spindle axis perform an accelerated rotation at maximum capacity from a process start position; sections for respectively detecting a maximum acceleration, a residual rotation amount and a current speed of the spindle axis; a section for making the spindle axis perform a decelerated rotation at maximum capacity to reach a target thread depth after the accelerated rotation; and a section for executing a torque-limiting during the accelerated rotation of the spindle axis, in such a manner that a torque command lower than a maximum torque command is given to the spindle axis at a start of acceleration, and thereafter the torque command is gradually increased so that the maximum torque command is given to the spindle axis when a predetermined time has elapsed.
    Type: Grant
    Filed: March 29, 2016
    Date of Patent: March 6, 2018
    Assignee: FANUC CORPORATION
    Inventors: Yuuki Morita, Tadashi Okita
  • Publication number: 20180045583
    Abstract: To provide a motor control device that specifies a type of temperature sensor by a simple technique, even in a case of the type of temperature sensor installed to a motor being unclear.
    Type: Application
    Filed: August 1, 2017
    Publication date: February 15, 2018
    Applicant: FANUC CORPORATION
    Inventors: Yuuki MORITA, Tadashi OKITA
  • Patent number: 9887660
    Abstract: A motor control device of the present invention is a control device for a motor for driving a feed shaft of a machine tool, and includes: a power outage detector for detecting a power outage of a power source for supplying power to drive the motor; a forcible decelerator for forcibly decelerating the motor in response to a torque command when a power outage is detected; a DC link voltage monitor for monitoring a DC link voltage applied to an amplifier for driving the motor; a determination unit for determining whether the value of the DC link voltage is greater than a first threshold, or whether the change ratio of the DC link voltage is greater than a second threshold; and, a torque command limiter for limiting the torque command to a predetermined torque command limiting value, in accordance with the result of determination at the determination unit.
    Type: Grant
    Filed: July 20, 2015
    Date of Patent: February 6, 2018
    Assignee: FANUC CORPORATION
    Inventors: Shoutarou Hashimoto, Tadashi Okita
  • Publication number: 20180034391
    Abstract: To provide a motor control device capable of causing a motor to rotate in any rotation direction, even when leaving the connection state of the motor of a machine tool as standard.
    Type: Application
    Filed: July 24, 2017
    Publication date: February 1, 2018
    Applicant: FANUC CORPORATION
    Inventors: Tadashi OKITA, Yuuki MORITA, Daisuke TAJIMA
  • Publication number: 20170344029
    Abstract: Included are a first position detection part that detects a first position which is the position of a movable part; a second position detection part that detects a second position which is the position of a driven part; a positional error calculation part that calculates positional error, which is deviation between a converted first position detection value and a second position detection value; and a positional error variation calculation part that calculates an absolute value for variation of positional error since reversal of a position command was detected, in which addition of a backlash correction amount is started if the absolute value for the variation of the positional error exceeds a first reference value, and addition of a backlash acceleration amount is started if the absolute value of variation of the positional error exceeds a second reference value.
    Type: Application
    Filed: May 23, 2017
    Publication date: November 30, 2017
    Inventors: Shoutarou HASHIMOTO, Tadashi OKITA, Yuuki MORITA
  • Patent number: 9812947
    Abstract: A motor control device includes a converter that converts AC power into DC power, a smoothing capacitor provided in a DC link, an inverter that converts the DC power in the DC link into AC power for a motor, a capacitor capacity measurement unit that measures a capacity of the smoothing capacitor, a data record unit that records a plurality of pieces of data composed of a measurement value of the capacity of the smoothing capacitor and a date or both a date and time when the measurement has been performed, a deterioration characteristic calculation unit that calculates a deterioration characteristic line indicating a change of the capacity of the smoothing capacitor with respect to elapsed time, on the basis of the recorded data, and a life prediction unit that predicts a period when a life of the smoothing capacitor ends, on the basis of the deterioration characteristic line.
    Type: Grant
    Filed: March 23, 2016
    Date of Patent: November 7, 2017
    Assignee: FANUC CORPORATION
    Inventors: Kenta Yamamoto, Tadashi Okita