Fanuc Corporation

Kenji Takahashi

Tadashi Okita

Yuuki Morita

Yukio Toyozawa

Tomohisa Tsutsumi

Yasusuke Iwashita

Keiji Sakamoto

Masaru Oda

Kazuhisa Otsuka

Yukio Toyosawa

Yuuki Katou

A screw fastening system includes: an electric motor; a holding device for holding the electric motor; a support member mounted to a drive shaft of the electric motor; a screw fastening machine supported by the support member, and capable of executing a screw fastening operation with pulsed fastening control; and a motor control unit for controlling the electric motor to reduce a fastening-torque reaction force, caused by the screw fastening operation with pulsed fastening control executed by the screw fastening machine, with respect to the holding device.

Screw fastening system

A synchronous motor control device for controlling driving of a synchronous motor through sensorless control includes a DC excitation instruction generation unit that generates an instruction for supplying, to the synchronous motor, fixed excitation current having a current phase fixed; a torque zero equivalence detection unit that detects, on the basis of data relating to voltage or current control on the synchronous motor, a point of time at which torque generated in a rotor of the synchronous motor becomes equivalent to zero in a time period during which the excitation current based on the instruction is flowing through the synchronous motor; and a magnetic pole position update unit that initializes a magnetic pole position on the basis of the fixed current phase at the detected point of time at which the torque becomes equivalent to zero.

Synchronous motor control device

Provided is a magnetic pole position detection device with which it is possible to shorten the detection time of the initial magnetic pole position of the rotor of a synchronous motor. A magnetic pole position detection device that detects the magnetic pole position of the rotor of the synchronous motor, the magnetic pole position detection device comprising an excitation command unit that excites the synchronous motor while changing the current phase of the excitation current from a preset initial value, and a torque zero determination unit that determines whether the torque generated by the rotor has reached zero, the excitation command unit: continuously executing an operation for exciting the synchronous motor using, as the current phase of the excitation current, a value obtained with a subtraction process for subtracting, from the initial value, a phase angle corresponding to the cumulative value of the movement amount of the rotor from the starting point of excitation at the initial value of the current phase, during the period after the synchronous rotor was excited at the initial value of the current phase until the torque is determined to have reached zero; and acquiring, as the magnetic pole initial position, the value obtained with the subtraction process when the torque is determined to have reached zero.

Magnetic pole position detection device

A magnetic pole initial position detection device includes: a direct-current excitation command generation section configured to generate a first command for causing a constant excitation current with a current phase fixed to a first phase to flow through the synchronous motor; a torque-zero determination section configured to determine whether a torque generated in the rotor of the synchronous motor is zero when the excitation current based on the first command flows through the synchronous motor; and a magnetic pole initial position acquisition section configured to acquire the magnetic pole initial position of the rotor of the synchronous motor on a basis of a rotor actual position at or near a point in time when the torque-zero determination section determines that the torque is zero; a number of pole pairs of the synchronous motor; and an excitation phase during direct-current excitation under the first command.

Magnetic pole initial position detection device using direct-current excitation method and magnetic pole position detection device

A seam inspection apparatus can automatically determine the quality of an image of a seam of a sewn product. The seam inspection apparatus includes an image data acquisition unit that acquires image data of a seam of a sewn product, a feature extraction unit that extracts a feature quantity of the seam from the image data of the seam of the sewn product acquired by the image data acquisition unit, and a quality determination unit that performs quality determination of the seam based on the feature quantity of the seam.

Seam inspection apparatus

An abnormality diagnosing device diagnoses a driving abnormality of a single motor driven by a plurality of motor driving devices. The motor driving devices drive the motor by supplying three-phase alternating currents to a plurality of three-phase windings possessed by the motor. The abnormality diagnosing device is equipped with a rotational speed acquisition unit for acquiring a rotational speed value of the motor, a current acquisition unit for acquiring phase current values of respective phases flowing through the three-phase windings, and a determination unit for determining the presence of an abnormality, if an absolute value of the rotational speed value exceeds a predetermined value, and an absolute value of the phase current value of any one phase of the three-phase windings is less than a threshold value continuously for a predetermined time period.

Abnormality diagnosing device and abnormality diagnosing method

An abnormality diagnosing device diagnoses a driving abnormality of a single motor driven by a plurality of motor driving devices. The plurality of motor driving devices calculate a plurality of voltage command values based on a speed command, and voltages are applied to a plurality of windings possessed by the motor based on the plurality of calculated voltage command values, thereby driving the motor. The abnormality diagnosing device is equipped with a command value difference calculating unit for calculating a difference between the plurality of voltage command values calculated by the plurality of motor driving devices, and a determination unit for determining the presence of an abnormality, when an absolute value of the difference calculated exceeds a first threshold value continuously for a predetermined time period.

An anomaly diagnosing device diagnoses an anomaly in a single motor driven by multiple motor drive units. The multiple motor drive units supply AC currents to multiple multi-phase windings of the motor to drive the motor. The anomaly diagnosing device includes: a power consumption calculator for calculating power consumption in each of the multi-phase windings; a power difference calculator for calculating a difference in power consumption between the multi-phase windings; and a determination unit for determining that an anomaly is occurring when the absolute value of the difference has exceeded a threshold for a predetermined period of time.

Anomaly diagnosing device and anomaly diagnosing method

A current control device of a synchronous motor comprises a provisional d-phase current command calculation unit; a voltage amplitude calculation unit calculating a magnitude of a voltage command vector in a previous sampling period; a voltage ratio calculation unit determining a voltage ratio between the magnitude of the voltage command vector and a maximum output voltage of an amplifier; a target d-phase current calculation unit obtaining a d-phase current command in the previous sampling period, and calculating a target d-phase current command from the voltage ratio and the d-phase current command; a correction value calculation unit determining a correction value by passing a difference between the provisional d-phase current command and the target d-phase current command through a low-pass filter; and an adder adding the correction value to the d-phase current command in the present sampling period to calculate a new d-phase current command.

Current control device of synchronous motor

A detection device for detecting a magnetic pole position of a synchronous motor includes a generating unit for generating a magnetic pole correction value based on the difference between a forward rotation d-phase voltage command and a reverse rotation d-phase voltage command, the d-phase voltage commands being used for rotating the synchronous motor and generated when the synchronous motor is driven in forward and reverse directions, respectively, by applying a prescribed d-phase current command after detecting a magnetic pole initial position at power-on of the synchronous motor, and a correcting unit for correcting the magnetic pole initial position based on the magnetic pole correction value and on a sensor reference position which defines a reference position of a sensor attached to the synchronous motor, and a control apparatus equipped with the detection device controls the rotation of the synchronous motor based on the corrected magnetic pole initial position.

Detection device for detecting magnetic pole position of synchronous motor, and control apparatus equipped therewith

A motor control apparatusthat controls a rotation speed of a motor driven according to a speed command includes an abnormal-rotation detectorwhich determines that the motor is in an abnormal-rotation state, such as a runaway, when a speed deviation Ver obtained by subtracting a detection speed TSA of a motor rotation from a speed command VCMD is equal to or larger than a threshold value, when a sign of a product of acceleration &#x394;TSA obtained by subtracting a last detection speed from a detection speed this time that is detected in a predetermined cycle and a torque command Tc obtained by proportionally integrating the speed deviation is negative, and when an integration value VerSUM of the speed deviation Ver exceeds a predetermined value ALMlevel. With this arrangement, an abnormal rotation of the motor can be instantly detected even during acceleration or deceleration of the motor, thereby increasing the performance of protecting the motor.

Motor control method and motor control apparatus

A floating cylinder,and a rotating shaft fixing cylinder,are attached to a flange RB,at the distal end of a robot arm via an attaching member,. Attached to the floating cylinder,is a rotary tool,. To mount or demount a bladed tool to or from a collet chuck,, the rotating shaft fixing cylinder,is operated to advance a stopper,so that a rotating shaft,of the rotary tool is locked. The chuck nut of the collet chuck,is inserted and fixed into a collet fixing groove in which the bladed tool is stored. The robot is operated so as to rotate the flange RB,, by which the rotating shaft,and the chuck nut of the collet chuck,are rotated relatively to tighten or loosen the bladed tool in the collet chuck

Automatic bladed tool changer

A servo controller capable of controlling motors to be driven in different control modes, such as a synchronous motor and an induction motor, irrespectively of the type of the motor, and also capable of carrying out servo control by using incremental feedback signals. A control section common to individual motors and a control section dedicated to each motor are provided in a servo controller. The common control section is always used, while the dedicated control section is selectively used in accordance with the motor to be driven. Thereby, motors each requiring a different control mode can be controlled by the servo controller of one type. The use of th servo controller of one type can reduce maintenance management and a load on a CNC. Also, the provision of the control section common to individual motors can restrain increases of size, installation area and manufacturing cost of the device.

Growing community of inventors

Yamanashi, Japan

Kenji Takahashi