Patents Assigned to Okúma Corporation
  • Publication number: 20220226953
    Abstract: A thermal displacement compensation apparatus includes a temperature measuring unit, a thermal displacement estimating unit, a thermal displacement compensation unit, a displacement measuring unit, a data recording unit, a thermal displacement compensation learning unit, and a displacement measurement timing diagnostic unit. The displacement measuring unit measures a displacement of a machine tool after compensating an axis command value. The thermal displacement compensation learning unit determines a thermal displacement estimation formula based on temperature information and the displacement recorded in the data recording unit. The displacement measurement timing diagnostic unit compares the temperature information at a past displacement measurement recorded in the data recording unit with current temperature information obtained from the temperature measuring unit, and determines whether to measure the displacement by the displacement measuring unit or not at a predetermined diagnosis timing.
    Type: Application
    Filed: December 15, 2021
    Publication date: July 21, 2022
    Applicant: OKUMA CORPORATION
    Inventor: Yuji MIZOGUCHI
  • Patent number: 11378379
    Abstract: A tool cutting edge measuring device that is mounted on a horizontal lathe and multitasking machine includes contact type sensors and an arm. The sensors are configured to measure cutting edge positions of tools in a machining chamber and the arm is movable between an advance position and a retracted position. The arm advances into the machining chamber at the advance position and retracts from the machining chamber at the retracted position. The arm has distal ends provided with two branching units branched into the X-axis direction and the Z-axis direction at the advance position and the sensors are mounted to the respective branching units.
    Type: Grant
    Filed: September 11, 2020
    Date of Patent: July 5, 2022
    Assignee: Okuma Corporation
    Inventor: Shinya Naruse
  • Patent number: 11376695
    Abstract: A work table includes a baseplate, a plurality of levers, a clamp plate, a lock mechanism, and an unlocking mechanism. The plurality of levers are disposed on a concentric circle on the baseplate. Guide bars protrude upward from the plurality of levers. The plurality of levers are each disposed to be movable in a radial direction of the circle. The clamp plate is placed on top surfaces of the levers. The clamp plate has elongated holes in the radial direction through which the guide bars penetrate. The lock mechanism urges the clamp plate downward such that the respective levers are fixed in a manner sandwiched between the baseplate and the clamp plate. The unlocking mechanism releases the fixing of the respective levers by the lock mechanism.
    Type: Grant
    Filed: April 9, 2020
    Date of Patent: July 5, 2022
    Assignee: Okuma Corporation
    Inventor: Koki Matsuura
  • Publication number: 20220184710
    Abstract: A turning process method for processing a step-shaped workpiece includes: feeding a tool in a rotation axis direction and/or a radial direction of a workpiece while rotating the workpiece; using a tool that includes an insert with a main cutting edge having a straight portion and a machine tool having a pivot shaft of the tool in the machine side; processing a peripheral surface of the small diameter portion by turning the pivot shaft so as to have a cutting edge angle of less than 90°, the cutting edge angle having an angle between the straight portion of the main cutting edge and the rotation axis direction; and processing an end surface and a peripheral surface of the large diameter portion by turning the pivot shaft so as to have the cutting edge angle of 90° or more at a front of the large diameter portion.
    Type: Application
    Filed: December 1, 2021
    Publication date: June 16, 2022
    Applicant: OKUMA CORPORATION
    Inventor: Kazunori FUJISE
  • Publication number: 20220184766
    Abstract: A processing abnormality diagnostic device includes an abnormality diagnostic unit that diagnoses whether processing is abnormal using an abnormality threshold by a preset diagnostic model, a success or failure input unit that inputs success or failure of the diagnosis of the abnormality by the abnormality diagnostic unit, a measure determination unit that determines a measure when the diagnosis of the abnormality is input as failure through the success or failure input unit, an abnormality threshold change unit that updates the abnormality threshold, and a learning unit that relearns the diagnostic model using operation information of the machine tool when the diagnosis of the abnormality has failed. The measure determination unit determines which of the abnormality threshold change unit and the learning unit is to be adopted as the measure based on the operation information diagnosed by the diagnostic model when the diagnosis of the abnormality has failed.
    Type: Application
    Filed: December 1, 2021
    Publication date: June 16, 2022
    Applicant: OKUMA CORPORATION
    Inventor: Eisuke SOGABE
  • Publication number: 20220164704
    Abstract: A method for labeling a data set of a supervised learning machine includes: calculating a deviation degree from a reference state A for each corresponding data in cases where a plurality of state estimation targets are in the reference state A and a reference state B; calculating a normalized deviation degree by taking a map of the deviation degree from A for each of the corresponding data with a map set for each of the state estimation targets. The map is allowed to map the deviation degree from A in A on a specified value to be output by the supervised learning machine in A; allowed to map the deviation degree from A in B on a specified value to be output by the supervised learning machine in B.
    Type: Application
    Filed: November 22, 2021
    Publication date: May 26, 2022
    Applicant: OKUMA CORPORATION
    Inventor: Hiraku SUGIURA
  • Patent number: 11338407
    Abstract: An error measurement method for a machine tool measures an error in a machine tool that includes two or more translational axes, a table, and a spindle head. The error measurement method includes installing a masterwork having a plurality of targets on the table and detecting a position of each of the targets using a sensor mounted to the spindle head to acquire a measured value regarding the position of each of the targets and to acquire an error value regarding the position of each of the targets using each of the acquired measured values and a preliminarily acquired calibration value regarding the position of each of the targets. The error measurement method further includes calculating at least one disturbance index value indicative of a degree of disturbance in the measurement for each of the targets, and determining whether the disturbance index value exceeds a preliminarily set threshold.
    Type: Grant
    Filed: October 26, 2020
    Date of Patent: May 24, 2022
    Assignee: Okuma Corporation
    Inventors: Takuya Kojima, Tetsuya Matsushita
  • Patent number: 11268884
    Abstract: An abnormality diagnostic method for a feed axis device that diagnoses an abnormality of the feed axis device including a screw shaft and a nut, the feed axis device being incorporated in mechanical equipment, the abnormality diagnostic method includes controlling an operation of the feed axis device such that the screw shaft operates in a predetermined operating pattern, detecting a physical quantity signal generated from the feed axis device, and performing an abnormality diagnosis for the feed axis device based on the physical quantity signal detected by the detecting in accordance with a predetermined abnormality diagnosis algorithm. The performing includes performing a frequency analysis on the physical quantity signal to extract respective frequencies corresponding to a plurality of operating positions in the operating pattern and performing the abnormality diagnosis based on change of the frequencies corresponding to the respective operating positions.
    Type: Grant
    Filed: October 2, 2020
    Date of Patent: March 8, 2022
    Assignee: Okuma Corporation
    Inventors: Mariko Ito, Takumi Hongo
  • Patent number: 11254007
    Abstract: A machine tool is disclosed which can suppress resonance of an in-machine robot even when vibration occurs during machining of a workpiece. Vibration of the in-machine robot is detected by a vibration sensor of the in-machine robot. When the vibration of the in-machine robot becomes greater than or equal to a threshold during machining of the workpiece, a controller changes a natural frequency of the in-machine robot by exchanging an end effector of the in-machine robot or by changing an orientation of the in-machine robot, to thereby suppress resonance of the in-machine robot.
    Type: Grant
    Filed: October 1, 2019
    Date of Patent: February 22, 2022
    Assignee: OKUMA CORPORATION
    Inventors: Kiyoshi Yoshino, Shoichi Morimura
  • Patent number: 11254010
    Abstract: A machine tool is disclosed which continues monitoring even when there is an obstacle such as swarf or a cutting fluid between a machining portion to be monitored and a visual sensor. A visual sensor is attached to an in-machine robot which is movable in a machine tool. A controller operates the visual sensor while judging influences of the swarf and the cutting fluid, automatically judges an orientation experiencing less influence, and executes monitoring from an optimum direction.
    Type: Grant
    Filed: October 2, 2019
    Date of Patent: February 22, 2022
    Assignee: OKUMA CORPORATION
    Inventor: Hiroyuki Sugiura
  • Patent number: 11247305
    Abstract: A numerical control device for a machine tool controls a machine tool having a main spindle for attaching a tool, a table holding a workpiece and a jig, three translational axes, and one or more rotation axis. The numerical control device includes an axis-dependent deformation error estimation unit, an input unit, a gravitational deformation estimation unit, a correction value calculation unit, and an addition unit. The correction value calculation unit calculates a correction value of the translational axes and/or the rotation axis with respect to an error of a position and/or a posture of the tool with respect to the workpiece, based on an estimated value of an axis-dependent deformation error, an estimated value of a gravitational deformation error, and command values. The addition unit adds the correction values to the command values.
    Type: Grant
    Filed: August 27, 2018
    Date of Patent: February 15, 2022
    Assignee: Okuma Corporation
    Inventors: Takuya Kojima, Tetsuya Matsushita
  • Patent number: 11243221
    Abstract: A monitoring device of a main spindle rotation speed in a machine tool displays a variation state of the rotation speed by a rotation speed variation unit using a display unit in the machine tool. The monitoring device includes a variation value setting unit, a drawing unit, a first display unit, and a settable range calculating unit. The settable range calculating unit is configured to calculate a settable range of a variation amplitude and a variation cycle based on a calculation formula. The calculation formula includes the variation cycle, a difference between a first rotation speed and a second rotation speed at mutually different timings among the rotation speeds varied relative to a reference rotation speed, an inertia of a rotating body, a rated output of a motor that drives a main spindle, and a usage proportion to the rated output of the motor.
    Type: Grant
    Filed: October 2, 2020
    Date of Patent: February 8, 2022
    Assignee: Okuma Corporation
    Inventors: Shunsuke Fujimaki, Akihide Hamaguchi
  • Patent number: 11243062
    Abstract: A position measurement method includes, acquiring a sensing position of a distal end of a reference tool, measuring and acquiring a position of a machined surface, The method further includes measuring a position of a reference block disposed on a side of the tool sensor and calculating a relative position of the reference block to the sensing position from the sensing position and the position of the reference block, mounting the position measurement sensor to the main spindle and measuring a position of the reference block, calculating a length direction correction value of the position measurement sensor from the position of the reference block measured in the mounting of the position measurement sensor and the relative position, and measuring the object by the position measurement sensor and correcting a measurement position of the object.
    Type: Grant
    Filed: October 22, 2020
    Date of Patent: February 8, 2022
    Assignee: Okuma Corporation
    Inventor: Reiji Kanbe
  • Patent number: 11243676
    Abstract: A numerical control system for a machine tool includes a display screen, a storage unit, and a control unit. The control unit executes a step of displaying, on the display screen, a designation screen that selects and designates one or more pieces of auxiliary information and auxiliary functions corresponding to each of basic work screens prepared for each work process using the machine tool, and associating with the basic work screen and storing in the storage unit one or more pieces of auxiliary information and auxiliary functions selected and designated by a user through the designation screen, and a step of simultaneously displaying, on the display screen, one basic work screen designated by the user among the basic work screens, and one or more virtual buttons that select one or more pieces of auxiliary information and one or more auxiliary functions, associated with the user-designated basic work screen.
    Type: Grant
    Filed: October 22, 2015
    Date of Patent: February 8, 2022
    Assignee: OKUMA CORPORATION
    Inventors: Kazunori Fujitsuka, Tadanobu Imai, Yasushi Fukaya
  • Publication number: 20220011100
    Abstract: An accuracy diagnostic device that diagnoses an influence on an accuracy of a machine tool due to a thermal deformation includes a temperature change rate calculation unit, an accuracy influence degree calculation unit, and an accuracy stabilization time period calculation unit. The temperature change rate calculation unit calculates a rate of a temperature change in a predetermined portion of the machine tool as a temperature change rate. The accuracy influence degree calculation unit calculates an influence degree on the machine tool accuracy due to the thermal deformation as an accuracy influence degree, based on the temperature change rate. The accuracy stabilization time period calculation unit calculates a time period until the machine tool accuracy is stabilized as an accuracy stabilization time period, based on the temperature change rate.
    Type: Application
    Filed: June 7, 2021
    Publication date: January 13, 2022
    Applicant: OKUMA CORPORATION
    Inventor: Yuji MIZOGUCHI
  • Publication number: 20210404800
    Abstract: An accuracy diagnostic device for a machine tool diagnoses an accuracy of the machine tool. The machine tool includes a change amount detection unit that measures a change amount. The change amount changes due to an installation environment and an operational motion. The accuracy diagnostic device includes a change-amount-reference-value recording unit that records a reference value of the change amount. The accuracy diagnostic device obtains the change amount measured by the change amount detection unit. The accuracy diagnostic device diagnoses a change of the accuracy of the machine tool based on a first change index derived from a magnitude of a change of the change amount per a predetermined period and a second change index derived from the current change amount and the reference value.
    Type: Application
    Filed: June 7, 2021
    Publication date: December 30, 2021
    Applicant: OKUMA CORPORATION
    Inventor: Yuji MIZOGUCHI
  • Patent number: 11195081
    Abstract: A diagnostic device diagnoses a state of a test object. The diagnostic device includes a physical model base diagnosis unit, a mathematical model base diagnosis unit, a model update necessity determination unit, and an update notification unit. The physical model base diagnosis unit is configured to perform the diagnosis using a feature quantity. The mathematical model base diagnosis unit is configured to perform the diagnosis using a machine learning model. The model update necessity determination unit is configured such that if diagnostic results by the physical model base diagnosis unit and the mathematical model base diagnosis unit differ, the model update necessity determination unit determines that at least one of a physical model or a mathematical model is necessary to be updated. The update notification unit is configured such that if the model update necessity determination unit determines that the update is necessary, the update notification unit notifies it.
    Type: Grant
    Filed: December 20, 2017
    Date of Patent: December 7, 2021
    Assignee: Okuma Corporation
    Inventors: Hiroshi Ueno, Tomoharu Ando, Takashi Norihisa, Takumi Hongo
  • Patent number: 11190122
    Abstract: A torque ripple and a position error caused by an offset error of the current sensor affects an electrical angle frequency of a motor. In an apparatus of the present disclosure, a computation device executes a power spectrum computing process when a three-phase alternating current motor is at a constant speed, and a value obtained by subtracting a position command value from a position detected by a position detector is fast Fourier transformed, to compute a power spectrum of a position error signal at the electrical angle frequency. Then, the computation device executes an offset correction computing process, to evaluate the power spectrum and to update an offset correction amount. By repeatedly executing these processes when the three-phase alternating current motor is driven at a constant speed, the torque ripple and position error caused by the offset error are reduced.
    Type: Grant
    Filed: June 19, 2019
    Date of Patent: November 30, 2021
    Assignee: OKUMA CORPORATION
    Inventors: Masayuki Ando, Satoshi Eguchi
  • Patent number: 11169512
    Abstract: An operation monitoring device includes an analytical data obtaining unit for obtaining analytical data that contain history information of a machine; a non-operation reason analysis unit for analyzing the state of the machine by classifying the state of the machine for every predetermined time as either of an operating state and a plurality of kinds of non-operating states, based on the analytical data, the operating state being a state in which the machine is operating, and the non-operating states being classified based on a reason for non-operation; a storage unit for storing an analysis result storage database that stores the result of analysis; a display unit for presenting to a user the result of the analysis; and a correction unit for correcting the result of the analysis according to an instruction from the user.
    Type: Grant
    Filed: May 22, 2018
    Date of Patent: November 9, 2021
    Assignee: OKUMA CORPORATION
    Inventor: Shinji Uemura
  • Patent number: 11169005
    Abstract: A sensor substrate includes a multi-layered substrate and a plurality of coils formed on the substrate, an upper-side coil includes a first sub coil including a plurality of conductor patterns connected in series with each other in the substrate, and a second sub coil including a plurality of conductor patterns connected in series with each other in the substrate, and in any of the even number of layers, the conductor pattern belonging to the first sub coil and the conductor pattern belonging to the second sub coil are aligned alternately in a planar direction, and one end of the first sub coil is connected to one terminal of a short land, while one end of the second sub coil is connected to the other terminal of the short land separated from the one terminal in the planar direction.
    Type: Grant
    Filed: July 10, 2019
    Date of Patent: November 9, 2021
    Assignee: OKUMA CORPORATION
    Inventor: Yasukazu Hayashi