Fanuc Corporation

Kenichi Takayama

Satoshi Ikai

Yasusuke Iwashita

Tadashi Okita

Hiroyuki Kawamura

Junichi Tezuka

Hajime Ogawa

Zhiwei Tang

A non-transitory computer readable information recording medium stores an evaluation program for operating first and second motor control units, for evaluating operation characteristics related to a control device including a first motor control unit configured to control a first motor driving a first axis, and a second motor control unit configured to control a second motor driving a second axis. The evaluation program operates the first and second motor control units so that a shape of a movement path of a control target moved by the first and second axes includes at least a cornered shape in which both rotation directions of the first and second motors do not invert, and an arc shape in which one of the first and second motors rotates in one direction, and a rotation direction of the other of the first and second motors inverts.

Computer readable information recording medium, evaluation method, and control device

A servo control system including a servo motor, a driven member driven, a coupling mechanism coupled with the servo motor and the driven member, and a motor control part controlling the servo motor. The motor control part includes a position command generating part generating a position command value of the driven member, a force estimating part estimating the drive force acting on the driven member, a compensating part compensating the position command value based on the drive force estimated by the force estimating part, and a control signal output part outputting a control signal to the servo motor based on a position command value compensated by the compensating part.

Servo control system with position compensation function for driven member

A servomotor controller includes a first and a second converter circuit that perform conversion between AC power of a power supply and DC power, a first inverter circuit that performs conversion between the DC power on the DC side of the first converter circuit and AC power on the side of a first motor, a second inverter circuit that performs conversion between the DC power on the DC side of the second converter circuit and AC power on the side of a second motor, and a power calculation unit that calculates an amount of power of the first motor, wherein control is performed so that the regenerative power of the first motor is supplied to the second motor through the power supply or the regenerative power of the second motor is supplied to the first motor through the power supply, on the basis of the amount of power.

Servomotor controller for reducing power peak

A motor control apparatus controlling a motor driving a machine tool includes, an abnormal load detecting unit that detects an abnormal load by monitoring a load of the motor, a retract amount storing unit that stores a plurality of retract amounts used when the machine tool performs a retract operation in response to detection of an abnormal load by the abnormal load detecting unit, a retract amount switching unit that switches a retract amount selected from the plurality of retract amounts in accordance with a result of determination of whether the machine tool is processing or not, and a retract amount adding unit that adds a retract amount selected by switching of the retract amount switching unit to an instruction value indicative of a movement amount of the machine tool.

Motor control apparatus capable of protecting process face at the time of occurrence of abnormal load

A numerical control device wherein a sinusoidal signal generated by a sine wave generation part is input by a control loop excitation part to a control loop of the control object, the input signal input to the control loop and the output signal from the control object are sampled by the data acquisition part periodically, and the sampling data is used by the frequency characteristic calculation part to calculate the frequency characteristic of the control loop to control the control object, wherein the frequency characteristic calculation part uses data obtained by inputting a sinusoidal signal obtained by shifting an initial phase of the sinusoidal signal by a phase shift part provided at a sine wave generation part by exactly a certain amount to the control loop a plurality of times to calculate the frequency characteristic of the control loop to thereby improve the measurement precision regardless of the sampling frequency.

Numerical control device having function of calculating frequency characteristic of control loop

A servomotor control system of the present invention includes: a multiple number of first servomotors for driving axes in a machine tool or others; a multiple number of converters for converting AC voltage into DC voltage; a multiple number of first inverters for converting DC voltage into AC voltage; second servomotors for rotating inertial bodies; a multiple number of second inverters for converting DC voltage into AC voltage; and a servomotor control unit for controlling the multiple first servomotors and the second servomotors, and is constructed such that the number of the second servomotors is less than that of the multiple second inverters, and at least one of the second servomotors includes a multiple number of independent windings, and at least part of the multiple second inverters are connected to the multiple independent windings provided for one of the second servomotors.

Servomotor control system including a buffer servomotor with a plurality of windings

A servo control device in the present invention corrects a position command to a feed axis, so as to compensate for an amount of stretch or contraction of a ball screw during operation, by taking into account an influence of tension applied to the ball screw. The amount of stretch or contraction of the ball screw is calculated, based on the tension acting on the ball screw on the side farther from the servo motor, a distance between two fixed units supporting the ball screw at its opposite ends, a distance from the fixed unit situated closer to the servo motor to a moving body, and a torque command to the servo motor. An amount of position correction of the feed axis is calculated, based on the calculated amount of stretch or contraction of the ball screw.

Servo control device for performing correction based on amount of stretch or contraction of ball screw

A motor control system () which includes a difference calculating part () which calculates a difference between a first position detection value of a moving part and a second position detection value of a driven part, a judging part () which judges if a moving part has engaged with the driven part when the moving part is made to move from any initial position in a first and second drive directions, a holding part () which holds the difference as initial difference linked with the first or second drive direction, when the moving part has engaged with the driven part, and a correction amount calculating part () which calculates a backlash correction amount, the correction amount calculating part using the difference based on the current positions of the moving part and the driven part and the initial difference to calculate the backlash correction amount.

Motor control system which corrects backlash

A servo controller, capable of controlling the motion of a movable body with high accuracy, without depending on the position of the movable body which is moved on a ball screw. The servo controller has a position command generating part which generates a position command value; a velocity command generating part which generates a velocity command value based on the position command value and a position detection value; a torque command generating part which generates a torque command value based on the velocity command value and a velocity detection value; and a position compensation calculating part which calculates an amount of expansion/contraction of the ball screw based on a distance from the servomotor to a nut threadably engaged with the ball screw and the torque command value, and calculates a position compensation based on the amount of expansion/contraction.

Servo controller having function for correcting amount of expansion/contraction of ball screw

A motor control apparatus for synchronously controlling a master axis motor for driving a master axis and a slave axis motor for driving a slave axis, includes: a master axis position detector which outputs position data of the master axis and a reference signal with a predetermined fixed period; a master axis receiving circuit which receives the position data and the reference signal output from the master axis position detector; a master axis computation circuit which computes a master axis error representing a difference between the position data received by the master axis receiving circuit and the position data acquired at the time of the reception of the reference signal; and a slave axis motor control unit which controls the operation of the slave axis motor by using the master axis error as a command for synchronizing the operation of the master axis motor.

Motor control apparatus for synchronously controlling master axis and slave axis

A tapping machine () executes a tapping operation by operating a spindle motor () and a feed axis motor () in synchronization, and includes a spindle reversal detector unit () for detecting the reversed operation of the spindle during the tapping operation, and a reverse correction amount production unit () for producing a reverse correction amount for improving follow-up performance of reversed operation of the feed axis at the time when the reversed operation of the spindle is detected by the spindle reversal detector unit (). When the reversed operation is detected by the spindle reversal detector unit, the reverse correction amount produced by the reverse correction amount production unit () is added to the speed instruction on a speed control loop of the feed axis control unit () or to an integrator () of the speed control loop.

Tapping machine

A motor drive includes a dynamic braking circuit for producing a deceleration torque utilizing a braking force caused by a synchronous motor acting as a generator when the synchronous motor is deenergized. The motor drive apparatus is equipped with a dynamic braking circuit fault detection capability, a DC power supply which is obtained by rectifying input AC power, voltage application function for applying a voltage to the windings of the synchronous motor and to the dynamic braking circuit for a predetermined length of time by switching power transistors connected to the DC power supply, current detection unit for detecting the value of a current flowing from the power transistors, and fault checking unit for checking the dynamic braking circuit for the presence or absence of a fault, based on the current value detected by the current detection unit and on a predefined threshold value.

Motor drive apparatus equipped with dynamic braking circuit fault detection capability

A controller for a servomotor capable of improving accuracy of positioning and quality of a machined surface by switching modes of correction of a position command or the like, and reducing a shock at the time of switching. A correction amount generating section obtains a correction amount based on a value of a correction factor such as machine temperature. When the external signal is in ON state, a position command or the like is corrected by the correction amount obtained by the correction amount generating section and sent via switches. A correction amount holding section holds the correction amount obtained by the correction amount generating section. When the external signal turns to OFF state, the connection of the switches is changed so that correction is performed by the correction amount held in the correction amount holding section. When the connection of the switches is changed, the correction amount does not change rapidly, so that the machine does not suffer a shock. In positioning, the external signal is turns to ON state, so that the positioning is carried out accurately by performing correction by the correction amount sent from the correction amount generating section. When a high-quality machined surface is required, the external signal is turned to OFF state so that the correction amount does not change to achieve improvement in the quality of a machined surface.

Growing community of inventors

Yamanashi, Japan

Kenichi Takayama