Patent application number | Description | Published |
20080258671 | CONTROL DEVICE HAVING EXCESSIVE-ERROR DETECTION FUNCTION - Abnormality of a position error is quickly detected in a control device in which feedforward control is introduced. A position error estimation processing unit calculates a position error estimation value Err, for example, from the equation V/PG×(1−α) (V: first order differential of position command, PG: position gain in position controller, α: feedforward coefficient in feedforward term calculating unit), and abnormality of the position error is detected using an excessive-error detection level calculating by adding a margin ΔE to the position error estimation value. | 10-23-2008 |
20080303476 | ELECTRIC MOTOR CONTROL DEVICE - An excitation current processor of a current controller processes the excitation current corresponding to the magnetic flux instruction from the magnetic flux instruction processor. It multiplies this excitation current with a boost coefficient to obtain an excitation current instruction. Here, the boost coefficient is determined based on the difference obtained by subtracting the magnetic flux estimation value processed by the magnetic flux processor based on the excitation current feedback from the voltage conversion device from the magnetic flux instruction input from the magnetic flux instruction processor. Further, the boost coefficient can be found from the function of time from the start of the rise of the magnetic flux. | 12-11-2008 |
20090091281 | MOTOR DRIVING APPARATUS - A motor driving apparatus having a converter, which receives AC voltage and converts it to DC power, and an inverter, which receives the DC power and converts it to AC power, includes a charge/discharge control circuit and a capacitor connected in parallel to a link section between the converter and the inverter, and energy stored in the capacitor C | 04-09-2009 |
20090097830 | MOTOR DRIVE DEVICE PROVIDED WITH DISTURBANCE LOAD TORQUE OBSERVER - A motor drive device ( | 04-16-2009 |
20090174349 | MOTOR DRIVE APPARATUS EQUIPPED WITH DYNAMIC BRAKING CIRCUIT FAULT DETECTION CAPABILITY - A motor drive apparatus | 07-09-2009 |
20090174357 | SERVO MOTOR CONTROLLER - A servo motor controller having: a frequency identification section that performs analysis based on a frequency response method and identifies the frequency of a disturbance exhibiting a specified phase lag; an input/output gain identification section that identifies the input/output gain at the frequency identified by the frequency identification section; and a magnification factor resetting section that resets an adjustment magnification factor by performing a specified operation on a ratio between the identified input/output gain and a specified target value of the input/output gain. | 07-09-2009 |
20090218976 | MOTOR DRIVING APPARATUS - A motor driving apparatus comprises a charge/discharge control circuit for controlling charge to or discharge from a capacitor connected in parallel in a link section between a converter and an inverter, and a current control means for controlling discharge current from the charge/discharge control circuit. The current control means controls discharge current from the charge/discharge control circuit based on input current to the inverter or output current from the converter so that output current from the converter is equal to a prescribed value. | 09-03-2009 |
20090230898 | SERVO AMPLIFIER WITH REGENERATIVE FUNCTION - A servo amplifier for a robot capable of avoiding an excessive capacity for dealing with a regenerative power to achieve downsizing, cost reduction and energy saving of the device. A servo amplifier for driving servomotors of a robot to perform an operation using an electric power from a power source. The servo amplifier comprises a changeable converter connected with the power source and a plurality of inverters electrically connected with the converter and the servomotors. The changeable converter is selectively provided as a converter having a regenerative function of returning a regenerative power generated in the servomotors to the power source, or a converter having a regenerative function of discharging the regenerative power through a resistor, depending on conditions of the operation by the robot. | 09-17-2009 |
20090237016 | MOTOR CONTROLLER - A motor controller capable of effectively utilizing electrical energy accumulated in a capacitor and achieving a reduction in capacitance of the capacitor. The motor controller includes a converter that receives an input AC voltage and performs AC-to-DC power conversion thereon, an inverter that receives DC power and performs DC-to-AC conversion thereon, and a capacitor and a charging/discharging control circuit connected in parallel with a DC link between the converter and the inverter. Electrical energy is supplied from the capacitor to the DC link via the charging/discharging control circuit. The charging/discharging control circuit has a circuit for discharging electrical energy accumulated in the capacitor and for stepping up a voltage of the capacitor when discharging the electrical energy. | 09-24-2009 |
20100072940 | SERVO MOTOR DRIVE CONTROL DEVICE FOR CALCULATING CONSUMED ELECTRIC ENERGY AND REGENERATED ELECTRIC ENERGY - A mechanical system includes a plurality of amplifier groups each having a common power source unit connected to a higher-level power source and a plurality of power supply units for supplying power to servo motors from the common power source unit. A servo motor drive control device of the mechanical system includes a plurality of amplifier group electric power detection units each determining an electric energy of the corresponding one of the amplifier groups. Each of the amplifier group electric power detection units totals individual periodic electric energy dEak of the servo motors connected to the power supply unit associated with the corresponding amplifier group thereby to determine an amplifier group periodic electric energy dEbg representing a consumed electric energy or a regenerated electric energy in the corresponding amplifier group and integrates the determined amplifier group periodic electric energy dEbg over a predetermined time length thereby to determine an amplifier group consumed electric energy Ebng. The individual periodic electric energy dEak takes a positive value when electric power is consumed by the servo motors, and takes a negative value when electric power is regenerated by the servo motor. | 03-25-2010 |
20100117568 | CONTROLLER FOR CALCULATING ELECTRIC POWER CONSUMPTION OF INDUSTRIAL MACHINE - A controller of an industrial machine provided with an electric motor, a peripheral apparatus and an amplifier for the motor. The controller includes a motor power-consumption calculation section calculating motor power consumption by multiplying a motor current detection value, a motor rotation-speed detection value and a predetermined motor torque constant together; a power loss calculation section calculating sum power loss of the motor and amplifier by adding motor power loss determined by multiplying a square of the motor current detection value by a predetermined motor winding-resistance value, amplifier power loss determined by multiplying the motor current detection value by a predetermined amplifier power-loss coefficient, and predetermined fixed amplifier power consumption together; a fixed power-consumption calculation section calculating fixed power consumption of the peripheral apparatus; and a total power-consumption calculation section determining total power consumption of the industrial machine in a predetermined time period by integrating, for the time period, the calculated motor power consumption, the calculated sum power loss and the calculated fixed power consumption. | 05-13-2010 |
20100181955 | MOTOR CONTROLLER FOR TANDEM CONTROL - In position tandem control in which one movable member is driven by two motors, an output of the integral element of the velocity control unit in the control system for one motor is copied to the integral element of the velocity control unit in the control system for the other motor. A preload is added to a torque command output from each of the velocity control units in the motor control systems for two motors so that torques in mutually opposite directions are generated to suppress backlash between gears. | 07-22-2010 |
20100207566 | CONTROL DEVICE FOR SERVO DIE CUSHION - A control device, for a servo die cushion, capable of improving a response after overshoot generated by collision of a slide and a die cushion. The control device has a local maximum point judging part which judges a local maximum point based on the detected speed of the servomotor; a speed correction value calculating part which calculates a speed correction value for the servomotor based on the judgment result and the detected speed of the slide; a second force commanding part which generates a second force command value, the second force command value decreasing from an initial value to a first force command value, the initial value being equal to the force detected value when reaching generally the local maximum point. The force command value is switched from the first force command value to the second force command value, when the force detected value reaches the local maximum point. | 08-19-2010 |
20100214809 | PWM RECTIFIER - Disclosed is a PWM rectifier in which switching losses in a semiconductor device are reduced without degrading the response of a control system. In a PWM overmodulation region, the modulation scheme is set to a three-phase modulation scheme. In other regions, a switchover condition such as the amplitude of an input current is acquired and compared with a switchover level. If the switchover condition equals or exceeds the switchover level, the modulation scheme is switched over to a modified two-phase modulation scheme which reduces the number of switching operations to two thirds for the same PWM frequency. | 08-26-2010 |
20100219787 | MOTOR DRIVE SYSTEM FOR DRIVING MOTOR PROVIDED WITH A PLURALITY OF WINDINGS - A motor drive system is provided with a plurality of axis control parts for outputting PWM commands using a position command, a plurality of current supply parts which supply current to the respective windings based on the PWM commands of the respective axis control parts, and which are connected to the respective windings, a motor position detector for outputting a signal of a rotor position of the motor, a first signal supply part for supplying the output signal to one current supply part of the plurality of current supply parts, and a second signal supply part for supplying the signal supplied through the first signal supply part to an axis control part corresponding to one current supply part, and the corresponding axis control part outputs a PWM command based on the signal supplied from the one current supply part through the second signal supply part to the corresponding axis control part and the position command, and the remaining axis control part outputs the PWM command based on the signal supplied from the corresponding axis control part to the remaining axis control parts and the position command. Thereby, a motor drive system capable of driving a plurality of inverters can be made simple. | 09-02-2010 |
20100295495 | SERVO CONTROL APPARATUS THAT PERFORMS DUAL-POSITION FEEDBACK CONTROL - A servo control apparatus that performs dual-position feedback control and thereby achieves a reduction in position error according to the purpose of machining. The servo control apparatus includes: a first position detector for detecting the position of a motor; a second position detector for detecting the position of a driven load; a first position error calculator for calculating a first position error based on a position command and motor position feedback; a second position error calculator for calculating a second position error based on the position command and driven load position feedback; a third position error calculator for calculating a third position error to be used for position control, by adding to the first position error a difference taken between the first position error and the second position error and passed through a time constant circuit; a selector for selecting either the second position error or the third position error for output; and a learning controller for learning an output of the selector, and for outputting an amount of compensation to be applied to the third position error. | 11-25-2010 |
20110057599 | 3D-TRAJECTORY DISPLAY DEVICE FOR MACHINE TOOL - A trajectory display device capable of correctly quantifying an error of a three-dimensional trajectory of a machine tool, and displaying or outputting the error. The trajectory display device has a command line segment defining part adapted to define a command line segment which connects two temporally adjacent points, in relation to each commanded position; an error calculating part adapted to define a normal line extending from the actual position to each command line segment and calculate an error of the actual position relative to a commanded trajectory, the error being determined as a shorter one between a length of a shortest normal line among the defined normal lines and a length of a line segment extending from the actual position to a commanded position which is the nearest from the actual position. | 03-10-2011 |
20110063122 | NUMERICAL CONTROLLER HAVING A FUNCTION FOR DETERMINING MACHINE ABNORMALITY FROM SIGNALS OBTAINED FROM A PLURALITY OF SENSORS - Signals from a plurality of sensors (vibration sensors, temperature sensors, and humidity sensors) disposed at places on a machine are input through a communication circuit to a numerical controller that controls the machine. The numerical controller uses vibration information, temperature information and humidity information obtained from these sensors to determine whether the machine is in an abnormal state. | 03-17-2011 |
20110147028 | MOTOR CONTROL APPARATUS HAVING A FUNCTION TO CALCULATE AMOUNT OF COGGING TORQUE COMPENSATION - A motor control apparatus that can calculate a proper amount of cogging torque compensation even in cases where components due to other factors than cogging torque (for example, components due to gravitational torque, etc.) are superimposed on a torque command being output during constant slow-speed feed operation. The motor control apparatus includes: a torque command monitoring unit which monitors a torque command when the motor is caused to operate at a constant speed; an approximation calculation unit which calculates a torque command approximation component by approximation from the torque command monitored over an interval equal to an integral multiple of the cogging torque period of the motor; a second torque command calculation unit which calculates a second torque command by subtracting the torque command approximation component from the torque command; a second torque command frequency analyzing unit which extracts frequency components, each at an integral multiple of the fundamental frequency of the cogging torque, by performing frequency analysis on the thus calculated second torque command; and a cogging compensation amount calculation unit which calculates the amount of cogging compensation from the amplitude and phase of the extracted frequency components. | 06-23-2011 |
20110175557 | MOTOR DRIVING APPARATUS HAVING POWER REGENERATION FUNCTION - A motor driving apparatus wherein provisions are made to ensure that the regenerative operation of a rectifier continues as long as the supply of power from an inverter continues, and that the regenerative operation of the rectifier stops when the supply of power from the inverter ends. The apparatus includes: a detection unit which detects an input voltage and current; an instantaneous effective power calculation unit which, based on the detected input voltage and current, calculates instantaneous effective power supplied from the rectifier to the inverter; a DC component calculation unit which, based on the value of the calculated power, calculates the DC component of the effective power; and a regenerative operation stopping decision unit which compares the value of the calculated DC component with a predetermined threshold value and decides that a power regeneration operation for feeding regenerative power from the inverter back into the power supply be stopped. | 07-21-2011 |
20110182398 | MOTOR DRIVING DEVICE HAVING POWER FAILURE DETECTION FUNCTION - A motor driving device that accurately achieves power failure detection according to a power failure tolerance with a relatively simple configuration. A counter input computing unit determines, as a counter input value, a value that is inversely proportional to the power failure tolerance determined from a voltage amplitude value and supplies the counter input value to a counter. The counter accumulates the input value at predetermined intervals and outputs an output value. A comparator determines that power failure occurs if the output of the counter | 07-28-2011 |
20110202167 | NUMERICAL CONTROLLER WITH TOOL TRAJECTORY DISPLAY FUNCTION - Coordinate values of a tool center point is calculated by obtaining coordinate values at each time of respective drive axes driven by a numerical controller. A tool radius compensation vector connecting the calculated tool center point at each time and an actual machining point is obtained. Then, coordinate values of the actual machining point are calculated based on the calculated coordinate values of the tool center point and the obtained tool radius compensation vector, and the trajectory of the actual machining point is displayed on a display. | 08-18-2011 |
20110234146 | CONTROLLER OF SPINDLE PROVIDED WITH ENCODER - The controller controls a spindle connected to an induction motor via a belt by controlling the rotational velocity of the induction motor. The spindle has an encoder attached thereto for detecting the position of the spindle, but the induction motor does not have a velocity detector attached thereto. The velocity of the induction motor is estimated from the spindle velocity obtained from output of the encoder, and slip of the belt is detected based on the estimated velocity of the induction motor. When occurrence of slip of the belt is detected, the estimated velocity of the induction motor will not be used for the control of the induction motor. | 09-29-2011 |
20110234147 | CONTROLLER FOR SPINDLE WITH ENCODER - A controller controls the rotational speed of an induction motor, thereby controlling a spindle connected to the induction motor. Although an encoder for detecting the position of the spindle is mounted on the spindle, a speed detector is not attached to the induction motor. The speed of the induction motor is estimated from a spindle speed obtained by the encoder, and an excitation frequency command for the induction motor is determined based on the estimated speed. | 09-29-2011 |
20110238338 | MOTOR DRIVING APPARATUS EASILY ANALYZABLE FOR CAUSE OF FAULT - Disclosed is a motor driving apparatus in which provisions are made so as to easily isolate the cause of a fault in the event of the occurrence thereof. The voltage and current in each phase of the AC power being supplied to a converter are detected, and the most recently detected data are stored in a power supply monitoring unit for a predetermined period of time. If an alarm occurs in the converter, inverter, or controller, the data currently held in the power supply monitoring unit are recorded in a recording unit. By displaying the thus recorded data, one can easily identify whether the cause of the alarm is due to the power supply or the motor driving apparatus itself. | 09-29-2011 |
20110241590 | MOTOR DRIVING APPARATUS HAVING FAULT DIAGNOSTIC FUNCTION - A motor driving apparatus capable of detecting during operation a ground fault and a phase-to-phase short circuit by distinguishing one from the other is provided while minimizing an increase in cost. The sum of three-phase AC currents supplied from a three-phase AC power supply to an AC/DC converter is detected by a current sensor. When overcurrent is detected by an overcurrent detector, if the sum of the currents detected by the current sensor is zero, it is determined that the fault is a phase-to-phase short circuit, but if the sum is not zero, it is determined that the fault is a ground fault. | 10-06-2011 |
20110260662 | MOTOR DRIVING APPARATUS HAVING FUNCTION OF DYNAMICALLY SWITCHING CONVERTER OPERATION MODE OF AC/DC CONVERTER - A motor driving apparatus is provided that performs AC/DC conversion by suppressing harmonics of the input at the time of normal operation, while on the other hand, allowing system operation to continue in the event of an overload by avoiding system stoppage. The motor driving apparatus, which drives a motor by supplying power from an AC power supply, includes: an AC/DC converter having a converter operation mode which is switched between a PWM converter operation mode in which an AC input voltage is converted into a DC voltage by applying PWM control to a plurality of power switching devices connected in serial and parallel fashion and a diode rectifier operation mode in which an AC input voltage is converted into a DC voltage by using a plurality of diodes each connected in reverse parallel with an associated one of the plurality of power switching devices; and a converter control unit which dynamically switches the converter operation mode of the AC/DC converter according to a load during powering of the motor. | 10-27-2011 |
20110298402 | MOTOR DRIVE DEVICE WITH FUNCTION OF SWITCHING TO POWER REGENERATIVE OPERATION MODE - A motor drive device comprising a converter for carrying out a power running operation for supplying power from a three-phase AC power supply to a three-phase AC motor and a power regenerative operation for returning energy generated by the three-phase AC motor to the three-phase AC power supply. The converter has power switching elements, a first power regenerative control unit for controlling an on/off action of the power switching elements at the time of carrying out the power regenerative operation by using pulse width modulation signal whose pulse width changes in accordance with a value indicated by a command signal; a second power regenerative control unit for controlling the on/off action of the power switching elements at the time of carrying out the power regenerative operation in order to generate respective power regenerative currents in a phase representing the maximum electric potential among three phases of the three-phase AC power supply and a phase representing the minimum electric potential among the three phases, and a power regenerative operation switching unit for switching control of the on/off action of the power switching elements at the time of carrying out the power regenerative operation between a control carried out by the first power regenerative a control unit and that carried out by the second power regenerative control unit. | 12-08-2011 |
20120056568 | MOTOR DRIVING APPARATUS HAVING DC LINK VOLTAGE REGULATING FUNCTION - A motor driving apparatus comprises: an AC/DC converter which converts AC voltage supplied from an AC power source into DC voltage through PWM switching control of a power switching device; and a DC/AC converter which converts the DC voltage into variable-frequency AC voltage for driving a motor in a controlled manner. The AC/DC converter includes: a control unit which generates, based on an error between the DC voltage and a DC voltage command value, a PWM signal for the PWM switching control of the power switching device; and a frequency/gain varying unit which sets the frequency of the PWM signal to be generated by the control unit and a control gain in the control unit higher than their normal levels during a period in which a load in the DC/AC converter varies. | 03-08-2012 |
20120068636 | MOTOR DRIVING APPARATUS - When the output of motor reaches or exceeds a predetermined value during acceleration of the motor, the control target value of the DC link voltage which is the voltage of a power storage device is gradually lowered in corresponding relationship to the motor output. When the motor enters a constant speed control mode, the DC link control target value is maintained at a constant level. When the motor enters a deceleration control mode, the DC link control target value is gradually raised in corresponding relationship to the motor output, and regenerative power is recovered by the power storage device and reused in the next control cycle. | 03-22-2012 |
20120068637 | MOTOR DRIVING APPARATUS - During motor acceleration control period that starts at time T | 03-22-2012 |
20120203374 | NUMERICAL CONTROLLER FOR MAKING POSITIONING COMPLETION CHECK - A numerical controller calculates the distance (rotation radius) between the rotation center axis of a rotary axis and a control target point using the machine conditions (including the axis structure and tool length) of a machine tool having a rotary axis and the coordinate values of the respective axes of the machine tool. Then, the preset positioning completion widths of the respective axes are compensated by the calculated rotation radius and a positioning completion check of the rotary axis is carried out using the compensated positioning completion widths. | 08-09-2012 |
20120326641 | MOTOR DRIVE APPARATUS EQUIPPED WITH ENERGY STORAGE UNIT - A motor drive apparatus includes an AC/DC converter which converts AC power supplied from a power supply to DC power, a DC/AC converter which converts DC power to AC power and vice versa, a DC link unit which connects the DC side of the AC/DC converter to the DC side of the DC/AC converter and delivers the DC power from one to the other and vice versa, an energy storage unit which includes at least one capacitor storage unit and at least one flywheel storage unit each of which is connected to the DC link unit and stores or supplies the DC power, and an energy control unit which performs control so that the energy storage unit stores or supplies the DC power. | 12-27-2012 |
20130009576 | MOTOR CONTROLLER HAVING ENERGY STORAGE UNIT - A motor controller includes: a converter circuit for converting AC power to DC power; an inverter circuit connected to a DC side of the converter circuit and converting DC power to AC power for driving a motor or converting AC power regenerated from the motor to DC power; an energy storage unit connected to the DC side of the converter circuit and the inverter circuit and storing or outputting DC power; and a control unit controlling amount of DC power to be stored or output in/from the energy storage unit on the basis of a motor operation instruction instructing operation of the motor. | 01-10-2013 |
20130026964 | CONTROL DEVICE THAT DRIVES ONE DRIVEN OBJECT BY TWO MOTORS - A control device that drives one driven object by a first motor and a second motor. A first processor has a first correction amount calculation unit configured to calculate an amount of correction for a torque command to the first motor based on a speed value difference between a speed value of the first motor and a speed value of the second motor in order to suppress vibrations. A second processor has a second correction amount calculation unit configured to calculate an amount of correction for a torque command to the second motor based on a speed value difference between a speed value of the first motor and a speed value of the second motor in order to suppress vibrations. | 01-31-2013 |
20130076287 | NUMERICAL CONTROLLER HAVING DISPLAY FUNCTION FOR TRAJECTORY OF TOOL - A numerical controller capable of visually and accurately analyzing a change of the tool trajectory before and after changing a processing condition, whereby a parameter of a drive axis can be properly adjusted. The numerical controller comprises a numeric controlling part which controls each drive axis based on a predetermined position command; a position data obtaining part which obtains position data of each drive axis controlled by the numerical controlling part; a tool coordinate calculating part which calculates a coordinate of a tool center point based on position feedback or obtained position data of each drive axis and information of a mechanical structure of a machine tool; a tool trajectory storing part which stores the calculated coordinate of the tool center point as a feedback trajectory; and a displaying part which displays the stored feedback trajectory on a display. | 03-28-2013 |
20130099705 | MOTOR DRIVING DEVICE HAVING REACTIVE CURRENT INSTRUCTION GENERATING UNIT - A motor driving device includes a converter that converts an input alternating current into a direct current, an inverter that inverts the direct current output by the converter into an alternating current for driving a motor, a voltage detecting unit that detects a voltage on a direct current output side of the converter, and a numerical control unit that causes the inverter to output a reactive current to increase electric power consumed in the motor, when the voltage detected by the voltage detecting unit exceeds a predetermined threshold. | 04-25-2013 |
20130106336 | MOTOR CONTROL APPARATUS EQUIPPED WITH DEAD-ZONE PROCESSING UNIT | 05-02-2013 |
20130134910 | MOTOR DRIVE APPARATUS HAVING POWER FAILURE DETECTION UNIT FOR DETERMINING PRESENCE OR ABSENCE OF POWER FAILURE - A motor drive apparatus includes a rectifier which converts AC power to DC power and DC power to AC power, an inverter which converts the DC power output by the rectifier to AC power and supplies the AC power to a motor, and which converts regenerative power from the motor to DC power and returns the DC power to the rectifier, a DC voltage detection unit which detects a DC output voltage of the rectifier, an AC voltage detection unit which detects an AC output voltage of the rectifier, a frequency calculation unit which calculates the frequency of the AC voltage; a storage unit which stores as a reference value the DC voltage at the start of the regenerative operation, and a power failure detection unit which determines the presence or absence of a power failure by using the DC voltage, the reference value, and the AC voltage frequency. | 05-30-2013 |
20130193897 | MOTOR DRIVE PWM RECTIFIER HAVING MODULATION SCHEME SELECTOR - A motor drive PWM rectifier includes a control section which generates the PWM signal in accordance with either a three-phase modulation scheme or a two-phase modulation scheme in which a PWM voltage command for one phase selected from among three phases each constituting the PWM voltage command in the three-phase modulation scheme is set and held at a level equivalent to a maximum value or minimum value of the PWM carrier and in which a PWM voltage command for the other two phases created by also applying an offset, required to achieve the setting, to the other two phases, a detecting section which detects three-phase AC current and outputs a detected current value, and a selecting section which selects the two-phase modulation scheme when the detected current value is larger than a first threshold value but smaller than a second threshold value, and otherwise selects the three-phase modulation scheme. | 08-01-2013 |
20130264988 | SERVO MOTOR CONTROL DEVICE FOR CONTROLLING SERVO MOTOR CONFIGURED TO DRIVE FEED AXIS OF MACHINE TOOL - An arithmetic coefficient setting unit sets a feedback control arithmetic coefficient to a value between a first feedback control arithmetic coefficient value for a cutting-feed and a second feedback control arithmetic coefficient value for a rapid-traverse operation smaller than the first feedback control arithmetic coefficient value. An arithmetic coefficient change unit continuously changes the feedback control arithmetic coefficient from the second feedback control arithmetic coefficient value to the first feedback control arithmetic coefficient value over a first period between a first time, which is an arbitrary time during the rapid-traverse operation, and the second time after the first time or a second period between a third time after the first time and before the second time, and the second time if it is predicted at the first time that the operating command switches from the rapid-traverse operation command to the cutting-feed command at the second time. | 10-10-2013 |
20130271049 | MOTOR CONTROL APPARATUS EQUIPPED WITH DELTA-SIGMA MODULATION AD CONVERTER - A motor control apparatus includes a power conversion unit which supplies drive power to a motor, a current detection unit which detects the value of a current flowing from the power conversion unit to the motor, a delta-sigma modulation AD converter which converts the current value into digital data by using a modulation clock as a system clock, and which starts to count the number of clock pulses of the modulation clock upon reception of a reference signal and, when the number of clock pulses counted reaches a predetermined count value, outputs the digital data obtained during a prescribed time interval which contains the reception time of the reference signal, and a command generating unit which generates, using the digital data supplied from the delta-sigma modulation AD converter, a drive command for commanding the power conversion unit to output commanded drive power. | 10-17-2013 |
20130320908 | SERVO CONTROLLER HAVING FUNCTION FOR CORRECTING AMOUNT OF EXPANSION/CONTRACTION OF BALL SCREW - 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. | 12-05-2013 |
20140062378 | MOTOR CONTROL SYSTEM WHICH CORRECTS BACKLASH - A motor control system ( | 03-06-2014 |