Okuma Corporation

Nagoya Institute of Technology

Aichi-prefectural Government

Takashi Norihisa

Tomoharu Ando

Naomitsu Yanohara

Hiroshi Ueno

Takumi Hongo

Masashi Miyaji

Fumihiro Itoigawa

Keiichi Kawata

Kazumasa Ishikawa

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.

Diagnostic device using both a physical model and mathematical model for anomaly detection

A method measures a frequency characteristic at a feed axis control unit configured to drive a motor in accordance with a velocity command value to control a velocity or a position of a movable portion of a driven body. The velocity command value includes a velocity reference value from a host device or a velocity command calculator and a sweep signal swept in order to measure the frequency characteristic. The method includes moving the feed axis in one direction by commanding the velocity reference value where a moving velocity of the feed axis is constant, exciting by providing a sine wave having an amplitude less than a magnitude of the velocity reference value to the sweep signal, and measuring the frequency characteristic of a feed axis drive system including the motor.

Frequency characteristic measuring method at feed axis control unit

There is provided a cutting method for cutting a work by rotating a rotary tool with a circular cutting edge around an axis while a cutting fluid is supplied thereto. Cutting is performed by means of the rotary tool which is rotated in the same rotational direction as an outflow direction of chips, and the rotary tool is rotated at a rotational speed of the rotary tool at which a circumferential speed of the cutting edge is higher than an outflow speed of the chips. Thus, the area of direct solid contact between the rotary tool and the chips is reduced with the aid of a dynamic pressure effect, and the abrasion of the rotary tool is suppressed.

Cutting method

A spiral groove flow passage with a clockwise spiral direction and a spiral groove flow passage with a counterclockwise spiral direction are provided inside a spindle. When the spindle is accelerated to rotate in the forward rotation direction, a pressure in the direction of causing a reverse flow of a coolant is applied to the left-hand spiral groove flow passage by the axial-flow pumping action, but a pressure in the forward direction is applied to the right-hand spiral groove flow passage by the same axial-flow pumping action to cancel out the pressure causing the reverse flow described above.

Spindle device

A machine diagnosing device includes a drive object driving force estimating unit for estimating drive object driving force based on a torque command value toward a servo motor which is acquired using a position command value, an elastic deformation error estimating unit for estimating an elastic deformation error of a ball screw with the drive object driving force, and a positional deviation calculating unit for calculating a positional deviation using a rotation position of the servo motor and the position of a table, and a machine damage diagnosing unit for diagnosing a machine damage by calculating a machine damage coefficient using the elastic deformation error and the positional deviation, comparing the obtained machine damage coefficient with a previously set threshold value, and diagnosing a damage state of the drive object.

Machine diagnosing method and device therefor

In a rotary joint for a rotary shaft device, ring-shaped inner seals and outer seals are projectingly arranged, and concentric with faces of a front joint disk and a rear joint disk opposing with each other respectively. A ring-shaped inner space communicates with forward communication holes, and a ring-shaped outer space communicates with backward communication holes. The inner and outer space are adjacently arranged concentrically between the inner seals and the outer seals. The forward communication holes and the backward communication holes in the reciprocating flow passages and the front joint disk are arranged at an equal distance in the peripheral direction of the opposing faces.

Rotary shaft device

The amount of lubricant oil supplied to a bearing is optimized. A main-shaft lubrication device includes a supply device for variably supplying lubricant oil to bearings which support a main shaft, a collection device for collecting, from the bearings, the lubricant oil supplied from the supply device, a measurement device for measuring the amount of lubricant oil collected by the collection device, and a control device for controlling the amount of lubricant oil to be supplied from the supply device.

Main-shaft lubrication device

Provided is a bearing state diagnostic apparatus in which a sound generated from a bearing is detected by a sound sensor, a detected value of the sound sensor is compared with data which was previously formed, thereby diagnosing a state of the bearing, wherein at least one sound sensor is disposed at a position separated away from an outer surface of a cylindrical support body in which at least one bearing is accommodated, the corresponding bearing and sound sensor are in communication with each other through a detection sound propagation path.

Bearing state diagnostic apparatus

In an outer ring, a plurality of lubrication oil flow paths which penetrates from an outer circumference surface of the outer ring to an inner circumference surface (in particular, raceway groove) are provided. Opening positions of the each lubrication oil flow paths are made different in a width direction being orthogonal to a rolling direction of a ball. At least one of the lubrication oil flow paths is used as a lubrication oil supply path, and a lubrication oil discharge path is selected from the other lubrication oil flow paths to adjust a range of lubrication oil amount, so that an amount of lubrication oil in the raceway groove is controlled.

Bearing and bearing apparatus

A controller includes a rotating direction detecting unitto detect the rotating direction of a servo motora reversing distance computing unitto compute a rotating angle of the servo motora rotation resistance computing unitto compute rotation resistance on the servo motor sideand an elastic deformation error amount computing unitto compute a deformation error amount of a ball screwIn the controller, when the rotating direction detecting unitdetects reverse of the servo motorthe rotation resistance computing unitcomputes rotation resistance based on a rotating angle &#x3b4;&#x3b8; of the servo motorafter the servo motor is reversed. The elastic deformation error amount computing unitcomputes the elastic deformation error amount &#x3b4; based on the computed rotation resistance. Thereby, a position command value inputted into the position control unitcan be corrected.

Servo motor controller

A spindle structure in which a noise occurrence due to a tap hole and a screw is effectively prevented. A nut for adjusting a preload of a bearing is threadedly engaged with an outer circumference of a spindle. On an edge of the nut, a plurality of tap holes for balance adjustment are provided at even intervals on a circumference centered around the axis of the spindle and to be parallel to the axial direction of the spindle. These tap holes are countersunk, and a plate screw is threadedly engaged so that an edge of each plate screw is flush with a surface of the nut. In addition, the plate screw is used as a balance weight by changing the length thereof.

Growing community of inventors

Niwa-gun, Japan

Takashi Norihisa