Patents Assigned to Okuma Corporation
  • Patent number: 10908581
    Abstract: A numerical control apparatus includes: a curvature radius calculating portion which calculates a first radius ra which is a radius of a passage arc C passing through three points of a start point Ps, an object point Pt, and an end point Pe as a curvature radius R at the object point Pt; a point sequence evaluating portion which calculates a chord error E to the passage arc C and compares the calculated chord error E and a previously defined permissible error; and a curvature radius correcting portion which calculates a second radius which is a radius of an arc in which a chord error with a front line segment and a rear line segment is the permissible error or less when the calculated chord error E exceeds the permissible error and corrects a curvature radius at the object point Pt to the second radius.
    Type: Grant
    Filed: September 3, 2019
    Date of Patent: February 2, 2021
    Assignee: OKUMA CORPORATION
    Inventor: Katsuya Hioki
  • Patent number: 10906147
    Abstract: A machine tool includes a base, a table, a main spindle, and a trunnion unit. The table is installed on the base. A tool is mounted to the main spindle. The main spindle is caused to approach a workpiece on the table along an up-down direction. The trunnion unit is configured to rotatably hold the table on which the workpiece is placed using a rotation axis along a front-rear direction as a center. The trunnion unit is disposed movable in a right-left direction.
    Type: Grant
    Filed: September 12, 2017
    Date of Patent: February 2, 2021
    Assignee: Okuma Corporation
    Inventor: Koji Tsuchida
  • Publication number: 20210019958
    Abstract: A relearning necessity determination method is provided for determining a necessity of relearning of a learned diagnostic model in a machine tool including a machining abnormality diagnosing unit. The machining abnormality diagnosing unit determines normal or abnormality of machining using the diagnostic model generated through machine learning. The method includes storing a cumulative cutting time or a cumulative cutting distance of a tool mounted to the machine tool as a tool usage, storing the tool usage when the machining abnormality diagnosing unit diagnoses the machining as machining abnormality, and determining the necessity of the relearning of the diagnostic model based on a frequency distribution of the tool usage stored in the storing of the tool usage.
    Type: Application
    Filed: July 13, 2020
    Publication date: January 21, 2021
    Applicant: OKUMA CORPORATION
    Inventor: Hiroshi UENO
  • Patent number: 10889012
    Abstract: A machine tool which removal-machines a workpiece by a tool includes an in-machine robot provided in a machining chamber, and a cleaning mechanism that cleans the in-machine robot by removing an adhering substance adhering to the in-machine robot. When the in-machine robot is cleaned, the in-machine robot moves relative to the cleaning mechanism and positions in proximity to the cleaning mechanism.
    Type: Grant
    Filed: August 3, 2017
    Date of Patent: January 12, 2021
    Assignee: OKUMA CORPORATION
    Inventor: Shoichi Morimura
  • Patent number: 10882151
    Abstract: An automatic pallet changer 2 includes: a pallet housing unit 11 having a plurality of pallet placement portions; and a pallet transfer unit 12 configured to transfer a pallet P that is at a required pallet placement portion and has an un-machined workpiece W attached thereto to a standby station S2 and configured to transfer a pallet P that is at the standby station S2 and has a machined workpiece W attached thereto to a required pallet placement portion. The pallet housing unit 11 includes: main housing portions 13a to 13f that have a plurality of rows of pallet placement portions, each having a plurality of stages, and are disposed to face the machine tool body 1; and three rows of secondary housing portions 14 that have one stage of pallet placement portions and are disposed above the machine tool body 1.
    Type: Grant
    Filed: February 3, 2020
    Date of Patent: January 5, 2021
    Assignee: OKUMA CORPORATION
    Inventor: Makoto Yoshida
  • Publication number: 20200380414
    Abstract: A data collection system includes a classification model storing unit, a model delivery unit, a classification result storing unit, an optimum model recommendation unit, and a teacher data recording unit. The model delivery unit delivers a classification model to the user environment. The classification result storing unit classifies each of the classification models on the classification model storing unit using data with a label transmitted from the user environment as an input. The classification result storing unit stores a classification result including at least one of classification correctness or a percentage of correct answers for each input data. The optimum model recommendation unit presents an appropriate classification model for the input data based on the classification result for each of the classification models. The teacher data recording unit records the input data as teacher data or test data of the classification model.
    Type: Application
    Filed: May 15, 2020
    Publication date: December 3, 2020
    Applicant: OKUMA CORPORATION
    Inventor: Hiroshi UENO
  • Publication number: 20200378738
    Abstract: A position measurement method for an object in a machine tool measures a position of an object with a probe using a machine tool. The machine tool includes three or more translational axes, a rotatable main spindle, and a table. The probe is a position measurement sensor mountable to the main spindle. The position measurement method includes preliminarily obtaining compensation values of contact positions in a radial direction of the probe in at least two directions where main spindle rotation angles are different by 180°, determining the main spindle rotation angle at a contact with a measurement surface of the object corresponding to the measurement content, and calculating a measurement value of the position of the object from a position of the probe at the contact with the measurement surface and the compensation value in accordance with the determined main spindle rotation angle.
    Type: Application
    Filed: May 13, 2020
    Publication date: December 3, 2020
    Applicant: OKUMA CORPORATION
    Inventor: Reiji KANBE
  • Patent number: 10850360
    Abstract: An information measuring device includes a sensor that obtains information on a phenomenon periodically occurring on an apparatus while being synchronized with the steady repetition of an operation and a control device. The control device associates the obtained information with an operation phase in the operation so as to generate change in the phenomenon in one cycle based on the information obtained during the operation of several times. Meanwhile, an operation cycle where the operation is repeated in the apparatus, a sampling cycle, and a duration where the operation is steadily repeated in the apparatus are included in measurement parameters. The control device calculates an optimum measurement parameter from a relation between the measurement parameters on at least one of the measurement parameters and changes the measurement parameter as a target to the optimum measurement parameter.
    Type: Grant
    Filed: July 20, 2017
    Date of Patent: December 1, 2020
    Assignee: Okuma Corporation
    Inventor: Takaaki Tanaka
  • Publication number: 20200353579
    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: Application
    Filed: April 9, 2020
    Publication date: November 12, 2020
    Applicant: OKUMA CORPORATION
    Inventor: Koki MATSUURA
  • Publication number: 20200338820
    Abstract: A three-dimensional shape processing method processes a workpiece into a predetermined three-dimensional shape by cutting work and additive manufacturing. The method includes forming a target surface for the additive manufacturing to be larger than a shape dimension of the three-dimensional shape, performing the additive manufacturing on the target surface that has been largely formed, and performing the cutting work on a region where the additive manufacturing has been performed to complete the three-dimensional shape.
    Type: Application
    Filed: April 8, 2020
    Publication date: October 29, 2020
    Applicant: OKUMA CORPORATION
    Inventor: Ryosuke SASAKI
  • Publication number: 20200298355
    Abstract: A workpiece fixing jig for fixing a workpiece to a table and/or a pallet of a machine tool includes a base plate, a support block, a bolt, and a drop prevention unit. The base plate is clamped or unclamped to the table and/or the pallet. The support block is disposed upright on the base plate. The support block has a placement surface for the workpiece on a top surface of the support block. The bolt is housed in the support block to be movable up and down. The bolt is projected from the placement surface to be screwable into a lower surface of the workpiece. The drop prevention unit prevents a drop of the bolt from the inside of the support block.
    Type: Application
    Filed: March 9, 2020
    Publication date: September 24, 2020
    Applicant: OKUMA CORPORATION
    Inventor: Tomomi IDO
  • Patent number: 10784803
    Abstract: A position control device includes a subtracter for subtracting a q-axis current detection value iq from a q-axis current command value iq* to output a q-axis current error ?iq, an adder for adding a q-axis current compensation amount iqc* for compensating for response timing of q-axis current to the q-axis current error ?iq, a q-axis current controller for amplifying an output of the adder by I-P control to calculate a q-axis voltage error ?vq and calculating a q-axis voltage command value vq* on the basis of the q-axis voltage error ?vq, and a second adder for adding a q-axis voltage feedforward amount vqf corresponding to a time derivative value s·iq of the q-axis current to the q-axis voltage command value vq* to calculate a final q-axis voltage command value.
    Type: Grant
    Filed: June 14, 2019
    Date of Patent: September 22, 2020
    Assignee: OKUMA CORPORATION
    Inventor: Satoshi Eguchi
  • Patent number: 10784730
    Abstract: A rotor of a synchronous motor has a rotor core and a permanent magnet. The rotor core has a plurality of magnet insertion apertures and a plurality of slits. The permanent magnet is disposed in each of the magnet insertion apertures such that the magnetic poles of the permanent magnets are directed in a diameter direction. The slits are formed on an radially outer side of the magnet insertion aperture so as to align with intervals along a side of the permanent magnet. Magnetic paths are defined between adjacent slits. A gap that is a slot open in the axial direction of the rotor core is formed on the opposite side from a plurality of magnetic paths across the permanent magnet to adjust the magnetic resistance of the magnetic paths for making a change in magnetic flux between adjacent magnetic paths small.
    Type: Grant
    Filed: October 23, 2018
    Date of Patent: September 22, 2020
    Assignee: OKUMA CORPORATION
    Inventors: Takanori Yokochi, Tatsuya Shizu
  • Patent number: 10780547
    Abstract: A machine tool includes a main shaft unit; a polishing head for processing a workpiece; and an unnecessary byproduct leakage preventing unit for preventing leakage of abrasive resulting from processing at or around a part of the workpiece, the part being processed, and wherein the unnecessary byproduct leakage preventing unit includes a cover provided separately from the polishing head, the cover having a structure that is open in three directions and that has walls in another three directions such that a protection space where to hold a part of the workpiece is defined, the cover for receiving the abrasive, and a movement mechanism for moving the cover so as to stay apart from the workpiece while the workpiece is not being processed and so as to have a part of the workpiece held in the protection space while the workpiece is being processed.
    Type: Grant
    Filed: April 23, 2018
    Date of Patent: September 22, 2020
    Assignee: OKUMA CORPORATION
    Inventors: Hiroyuki Sugiura, Shoichi Morimura
  • Patent number: 10760994
    Abstract: It is an object to perform an abnormality diagnosis for a feed axis without additionally adding a sensor or the like. A frequency characteristic of a feed axis and a damage frequency that occurs when the feed axis that has been damaged performs an axis operation are obtained, a frequency where a gain is maximized in the obtained frequency characteristic is calculated, and a feed velocity where the frequency matches the damage frequency is calculated. An axis operation is performed on the feed axis with the calculated feed velocity, and a frequency analysis is performed on servo information regarding a control of a servo motor during the axis operation. Then, the presence and absence of a peak of the damage frequency is confirmed from a result of the frequency analysis, and when the peak is present, it is determined that it is abnormal.
    Type: Grant
    Filed: July 19, 2017
    Date of Patent: September 1, 2020
    Assignee: Okuma Corporation
    Inventor: Takumi Hongo
  • Patent number: 10737333
    Abstract: A machine tool includes: a turret configured to hold a tool through a clamp mechanism; a workpiece main spindle device configured to rotatably hold a workpiece; a switching unit configured to change a clamp state of the clamp mechanism by using rotation torque of the workpiece main spindle device; and an in-machine robot configured to move the switching unit. The clamp mechanism includes a torque input hole to which rotation torque is applied to change the clamp state. The switching unit includes an input shaft coupled with the workpiece main spindle device, an output shaft coupled with the torque input hole of the clamp mechanism and configured to output torque to the torque input hole, and a transmission mechanism configured to transfer, to the output shaft, the rotation torque of the workpiece main spindle device input through the input shaft.
    Type: Grant
    Filed: January 23, 2019
    Date of Patent: August 11, 2020
    Assignee: OKUMA CORPORATION
    Inventors: Tomoki Hayashi, Shoichi Morimura
  • Patent number: 10725465
    Abstract: A state diagnostic device collects a usage state and diagnostic data of components, and selects, from the collected diagnostic data, at least one of diagnostic data obtained in a state where the usage state of the components is a truly normal state and diagnostic data obtained in a state where the usage state of the components is a truly abnormal state. The selected diagnostic data is defined as master data. A diagnosis result obtained by diagnosing the master data based on a current diagnostic model is compared with a diagnosis result obtained by diagnosing the master data based on a new diagnostic model, and whether the current diagnostic model is consistent with the new diagnostic model is determined. When the consistency is satisfied, the diagnostic model is updated from the current diagnostic model to the new diagnostic model.
    Type: Grant
    Filed: February 21, 2018
    Date of Patent: July 28, 2020
    Assignee: Okuma Corporation
    Inventors: Takahiro Tamakoshi, Hiroshi Ueno, Tomoharu Ando
  • Publication number: 20200230764
    Abstract: A method includes four steps, (1) setting an initial tool temperature, (2) estimating a temperature of a tool or a position measurement sensor based on the initial tool temperature and a temperature of a spindle, (3) estimating an amount of thermal displacement of the tool or the position measurement sensor with a preliminarily set tool thermal displacement estimation formula based on the estimated temperature, and (4) moving a feed shaft of the machine tool based on the estimated amount of thermal displacement to perform a correction. In the second step, the temperature of the spindle is measured, then a tool-mounted portion temperature of the spindle from the measured temperature is estimated. Further, the temperature of the tool or the position measurement sensor is estimated with the tool-mounted portion temperature, the initial tool temperature of the tool or the position measurement sensor, and the preliminarily set tool temperature estimation formula.
    Type: Application
    Filed: December 24, 2019
    Publication date: July 23, 2020
    Applicant: OKUMA CORPORATION
    Inventor: Yuji MIZOGUCHI
  • Patent number: 10702962
    Abstract: A swarf handling apparatus installed in a machining tool that performs machining operation accompanied with production of stringy swarf includes a swarf catching device. The swarf catching device includes a holder unit that holds the stringy swarf when the stringy swarf makes contact with the holder unit. The swarf catching device causes the holder unit to be floated in a region around a machining point in such a manner that the position of the holder unit is varied relative to the machining point, for catching the stringy swarf in the holder unit.
    Type: Grant
    Filed: April 27, 2018
    Date of Patent: July 7, 2020
    Assignee: OKUMA CORPORATION
    Inventor: Hiroyuki Sugiura
  • Patent number: 10688612
    Abstract: A machine tool is provided which can execute various works while suppressing increase in cost or size. The machine tool includes a tool spindle device which is a movable member which can move with respect to a mounting surface of the machine tool, and one or more serial-manipulator-type robots attached on the tool spindle device, which can move with the tool spindle device, and which have two or more degrees of freedom, and the robot includes two or more end effectors provided at positions different from each other with one or more joints therebetween.
    Type: Grant
    Filed: May 12, 2017
    Date of Patent: June 23, 2020
    Assignee: OKUMA CORPORATION
    Inventor: Shoichi Morimura