In a controller of a machine tool having a converter that converts an AC power supply to DC and a plurality of inverters that drive a feed axis and a spindle, a power outage preparation mode is judged when an AC power supply voltage becomes lower than a predetermined value, and power outage is judged when the power outage preparation mode continues for a time period exceeding a predetermined time period or when a DC voltage which is output from the converter becomes lower than V.sub.AL1. During the power outage preparation mode, a threshold V.sub.AL2 of a low voltage alarm provided at each inverter is changed to a value lower than V.sub.AL1. In addition, when the power outage is judged, a stopping operation or a retracting operation of the feed axis is executed.

A distributed motor control system includes motor control devices that individually control motors that coordinately drive an industrial machine. Each of at least two motor control devices of the motor control devices includes processing circuitry that performs sharing processing including sharing coordinated control data, used in coordinated driving of the industrial machine between the at least two motor control devices, via data communication, and control a corresponding motor using the coordinated control data shared via the sharing-processing.

To make it possible to evaluate quantitatively whether there is a problem on a machining surface. A simulator includes a memory unit that stores machining position data to be used when a machine tool machines a machining-target object, a machining surface simulation unit that uses the machining position data that is stored to perform a simulation of a machining surface, a surface texture calculation unit that calculates a surface texture of the machining surface that is simulated through the simulation of the machining surface, and a machining surface evaluation unit that evaluates the surface texture on the basis of an evaluation condition.

A servo motor controller is provided which enables an offset to be set more easily and accurately, in comparison to the conventional technique. A servo motor controller for controlling a servo motor of an industrial machine includes: a position detection unit that detects a position of the servo motor; a magnetic-pole detection unit that detects a magnetic-pole phase of the servo motor; and a phase calculation unit that determines a calculation-based phase based on position data of the servo motor and magnetic-pole gap information of the servo motor. The servo motor controller is configured to acquire an offset relationship between the magnetic-pole phase detected by the magnetic-pole detection unit and the calculation-based phase determined by the phase calculation unit, after a reference position is passed through.

The invention relates to a method for the closed-loop control of a proportional integral-type controller (2) in an instrumentation and control device (1) of a closed-loop control system (3), in particular a servovalve-actuator system, said controller (2) including a setpoint-weighting coefficient (β), said closed-loop control method comprising the consecutive steps of assigning (11) a unit value to the set-point weighting coefficient (β), optimizing (12) a closed-loop control of the controller (2) satisfying at least one predefined performance criterion, defining a characteristic tracking error (εTC) making it possible to respond to the performance constraints of the system to be closed-loop controlled, and assigning (132) a setpoint weighting coefficient (β) value, depending on the characteristic tracking error (εTC) and the closed-loop control of the controller (2).

A control device includes a program analysis unit, a program execution unit, and a servo control unit. The program analysis unit includes a machining/non-machining state determination unit that determines whether a target block of a machining program is in a machining state or a non-machining state, a switching necessity determination unit that determines whether it is necessary to perform switching of a control target axis of the target block and/or switching of an electrical current control cycle, and an information adding unit that adds a switching request and information after switching to an analysis result of the target block. The program execution unit includes a switching execution unit that executes the switching of the control target axis of the target block and/or the switching of the electrical current control cycle. The servo control unit controls the control target axis at the switched electrical current control cycle.

A motion control system comprises a power module, a plurality of servo motors, a servo control module, a motion control module and a microprocessor; the power module controls the working power supply output by the alternating-current power supply; the plurality of servo motors converts current signal of the output current flowing to an encoder output signal; the servo control module converts the encoder output signal into a first logic control signal; the microprocessor converts the first logic control signal into a third control signal and controls the servo control module to adjust the power module, which changes the working power supply output by the alternating-current power supply so as to drive servo motors. The invention provides a motion control system which integrates motion controller and supports multi-axis alternating-current servo driver to realize automatic control of the servo driver and improve control precision of the servo driver.

A servo controller includes: a servo control unit that controls a motor in a machine based on a position command; a position detection unit that detects the position of the motor; a positional error calculation unit that calculates a positional error between the position command and the position of the motor; a position abnormality detection unit that detects a position abnormality in the motor when the positional error is a first threshold or more; a load detection unit that detects a load torque on the motor; a load abnormality detection unit that detects a load abnormality in the motor when the load torque is a second threshold or more; an abnormality detection unit that detects an abnormality in the machine when the position abnormality or the load abnormality is detected; and a threshold change unit that changes the first or second threshold in response to the load state of the motor.

An auxiliary power supply device supplies electric power to an encoder when supply of electric power of a control device is cut off, and includes: a backup power source for supplying backup electric power to the encoder when supply of electric power of the control device is cut off; an auxiliary power source for supplying electric power to the encoder when the backup power source is removed; a remaining capacity determination unit for determining the remaining capacity of the auxiliary power source; a display unit for displaying an indication that the remaining capacity is insufficient when the remaining capacity determined by the remaining capacity determination unit is lower than a threshold; and a switch for actuating the display unit.

A servo control apparatus for a machine that performs machining by causing a plurality of synchronizing axes to operate cooperatively in synchronized relationship with a reference axis, the servo control apparatus comprising: a position detection unit for detecting at least one of the position of the servo motor and the position of a driven body; a position error calculation unit for calculating an error between the position command and the position detected by the position detection unit; a reference axis position acquisition unit for acquiring the positions of a plurality of reference axes; a reference axis selection unit for selecting one reference axis based on a machining condition of the driven body from among the plurality of reference axes whose positions have been acquired; and a learning control unit for performing learning control using an angle synchronization method, based on the error and the position of the selected reference axis.