| 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 |
| 20090009128 | CONTROL APPARATUS - A control apparatus of the present invention comprising a control unit outputting a control signal controlling a servo motor and suppressing natural vibration of a controlled object including a motor and a machine driven by the motor while controlling the controlled object, comprising a frequency analysis unit analyzing a frequency component included in a torque command, an analysis control unit controlling the start or stopping of the frequency analysis unit, a detection unit detecting a natural frequency of the controlled object from an analysis result of the frequency analysis unit, a-band rejection filter receiving as input the torque command, stripping the command of the natural frequency component, and outputting the resultant command to the motor through a current control unit and servo amplifier, and a filter characteristic setting unit setting the frequency to be stripped at the filter based on the natural frequency detected by the detection unit. | 01-08-2009 |
| 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 |
| 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 |
| 20100148714 | INERTIA ESTIMATING CONTROLLER AND CONTROL SYSTEM - A controller and a control system capable of estimating inertia of an article to be driven in a short period of time, with a small operation range of an electric motor. The controller for the motor has an inertia estimating part which includes a sine-wave command generating part which adds a sine-wave command to a torque command for the motor; a current feedback sampling part which obtains a current value of the motor; a speed feedback sampling part which obtains a speed feedback of the motor; an acceleration calculating part which calculates an acceleration value based on the speed feedback; and an estimated inertia calculating part which estimates the inertia of the article, based on a representative current value, a representative acceleration value and a torque constant of the motor, which are calculated from current and acceleration values in a plurality of cycles of the sine-wave command and stored in a sampling data storing part. | 06-17-2010 |
| 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 |
| 20110015877 | TOOL PATH DISPLAY APPARATUS FOR MACHINE TOOL - First and second screens are set for a tool path display apparatus for displaying a path of the tip of a tool attached to a machine tool. The first screen displays the three-dimensional path of the tip of the tool obtained by synthesizing the position information of the drive axes of a 5-axis machine tool. The second screen displays the waveforms of the position deviations and current instructions of the drive axes in chronological order. When a part (line segment) of the three-dimensional path of the tip of the tool is selected on the first screen, the display attribute of the corresponding time area is changed on the second screen so that the time area can be identified. | 01-20-2011 |
| 20110050146 | CONTROLLER OF ELECTRIC MOTOR HAVING FUNCTION OF ESTIMATING INERTIA AND FRICTION SIMULTANEOUSLY - A controller estimates Coulomb friction itself together with inertia and viscous friction, and reduces the influence of the Coulomb friction on the accuracy of the estimated inertia. In addition, the controller estimates inertia, viscous friction and Coulomb friction simultaneously with sequential adaptation in which a Fourier transformer is not used but an inverse transfer function model is used in order to minimize the estimated error. Data sampled for a predetermined time need not be accumulated, as a result, a large amount of data memory is unnecessary. | 03-03-2011 |
| 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 |
| 20110133681 | SERVOMOTOR CONTROL SYSTEM ENABLING HIGH-SPEED OSCILLATING MOTION TO BE HIGHLY PRECISE - A servomotor control system that includes a numerical control unit and servo control unit enables the use of learning control based on an angle synchronization method in high-speed oscillating motion performed by, for example, a jig grinder. The numerical control unit calculates a reference angle θ(=ωt), and also calculates a cyclic oscillation command F(t) according to the reference angle θ and a machining condition (angular velocity ω). The servo control unit calculates a difference between the value in the oscillation command F(t) and the position of the servomotor (positional difference ε) at intervals of a predetermined cycle, and performs learning control according to the reference angle θ, oscillation command F(t), and positional difference ε. | 06-09-2011 |
| 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 |
| 20120013287 | SENSORLESS INDUCTION MOTOR CONTROL DEVICE HAVING FUNCTION OF CORRECTING SLIP FREQUENCY OF MOTOR - A sensorless induction motor control device with a function of correcting a slip frequency wherein a slip frequency estimation unit estimates the slip frequency from at least one kind of current flowing through windings included in the motor, a voltage command signal value calculation unit calculates a D-phase voltage command signal value and a Q-phase voltage command signal value which are used for controlling a voltage applied to the sensorless induction motor using a Q-phase current command signal value calculated based on a difference between a speed estimation value, which is calculated using an estimation value of the slip frequency, and an externally supplied speed command signal value, an ideal voltage command signal value determination unit determines an ideal voltage command signal value using the speed command signal value and the Q-phase current command signal value, an actual voltage command signal value calculation unit calculates an actual voltage command signal value using the D-phase voltage command signal value and the Q-phase voltage command signal value, and a slip frequency correction unit compares the ideal voltage command signal value with the actual voltage command signal value and changes the estimation value of the slip frequency to make it smaller if the actual voltage command signal value is smaller than the ideal voltage command signal value. | 01-19-2012 |
| 20120059506 | SERVO CONTROL SYSTEM CAPABLE OF IMPROVING PROCESSING ACCURACY - A servo control system capable of using an angle-based synchronization learning control, even when a reference position is not given, while maintaining the advantage of the angle-based synchronization method. The servo control system has X-, y- and z-axes servo controllers, each configured to control x-, y- and z-axes servomotors, respectively. Each of x- and y-axes servo controllers has a reference signal generating part configured to generate a reference signal which monotonically increases or varies in one direction, based on the position command of each axis transmitted from a higher-level controller. | 03-08-2012 |
| 20120249025 | DETECTION DEVICE FOR DETECTING MAGNETIC POLE POSITION OF SYNCHRONOUS MOTOR, AND CONTROL APPARATUS EQUIPPED THEREWITH - 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. | 10-04-2012 |
| 20130039707 | TAPPING MACHINE - A tapping machine ( | 02-14-2013 |
| 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 |
| 20130187589 | MOTOR CONTROL APPARATUS WHICH LIMITS TORQUE COMMAND ACCORDING TO INPUT CURRENT OR POWER - A motor control apparatus includes, a converter which converts input AC to DC for output, an inverter which converts the DC output of the converter to provide an AC output for driving a motor, and an inverter control part for controlling the same, and a numerical control part which outputs a motor operation command for commanding the operation of the motor, and wherein when AC current or power input to the converter lies outside a predetermined range, the inverter control part controls the AC output of the inverter so that the motor is operated in accordance with a limited torque command produced by limiting a torque command originally specified in the motor operation command. | 07-25-2013 |
| 20130193900 | MOTOR DRIVE CONTROL DEVICE FOR LIMITING OUTPUT OF MOTOR - If it is predicted that the sum of the output of a servo motor and the output of a spindle motor exceeds power supplied by a rectifier unit, during a cutting operation, a motor drive control device controls alternating-current power of a first inverter unit so as to reduce the feed speed of at least one feed axis and controls alternating-current power of a second inverter unit so as not to limit torque of the spindle motor. Further, if it is predicted that the sum of the output of the servo motor and the output of the spindle motor exceeds power supplied by the rectifier unit, during an operation other than the cutting operation, the motor drive control device controls the alternating-current power of the second inverter unit so as to limit the torque so as not to reduce the feed speed. | 08-01-2013 |
| 20140132194 | CONTROL APPARATUS OF MACHINE TOOL INCLUDING FEED SHAFT MOTOR AND MAIN SPINDLE MOTOR - A control apparatus includes a converter for converting an AC voltage to a DC voltage, a feed shaft motor inverter for converting the DC voltage to an AC voltage for a feed shaft motor, a main spindle motor inverter for converting the DC voltage to an AC voltage for a main spindle motor, a power outage detection unit for detecting a power outage of the AC power supply, a voltage detection unit for detecting the DC voltage, and a control unit which, upon power outage of the AC power supply side, outputs a feed shaft motor deceleration command to the feed shaft motor inverter and outputs, to the main spindle motor inverter, a main spindle motor acceleration command when a DC voltage is greater than an upper limit and a main spindle motor deceleration command when the DC voltage is less than a lower limit. | 05-15-2014 |
| 20140292251 | SYNCHRONOUS CONTROL UNIT FOR SYNCHRONIZING TWO SHAFTS WITH EACH OTHER - In the first synchronous system of the synchronous control unit ( | 10-02-2014 |
