Abstract: 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.

Abstract: A control device, for a servo die cushion, by which the speed of a die cushion is prevented from largely deviating from the speed of a slide, whereby the press force between the slide and the die cushion is not significantly reduced. The control device includes a slide speed detector for detecting the speed of the slide, a die cushion speed detector for detecting the speed of the die cushion, and a die cushion speed commanding part for controlling the speed of the die cushion. When a tentative speed command of the die cushion is largely deviated from the detected slide speed, the command of the die cushion is corrected such that the absolute value thereof does not exceed the value calculated by adding the absolute value of the detected slide speed to a positive constant.

Abstract: 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.

Abstract: 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.

Abstract: 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 42 exceeds a threshold value.

Abstract: 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.

Abstract: 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.

Abstract: 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 ?(=?t), and also calculates a cyclic oscillation command F(t) according to the reference angle ? and a machining condition (angular velocity ?). The servo control unit calculates a difference between the value in the oscillation command F(t) and the position of the servomotor (positional difference ?) at intervals of a predetermined cycle, and performs learning control according to the reference angle ?, oscillation command F(t), and positional difference ?.

Abstract: 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.

Abstract: 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 f

Abstract: 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.

Abstract: A servo control apparatus that performs dual-position feedback control and thereby achieves a reduction in position error according to the purpose of machining.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: Time information t and positional information about each axis are obtained, and the three-dimensional coordinates of tool center point Pe at time t are calculated to display the path of the tool center point Pe at time t. Then, whether a fixed time has elapsed or not is decided. If the fixed time has elapsed, the coordinates of the tool vector start point Ps at time t are calculated to display a line segment connecting between tool vector start point Ps and tool center point Pe, which is the end point of the tool vector. This display enables the orientation of the tool at each tool center point to be grasped at a glance.

Abstract: 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.

Abstract: A press machine controller (10) for controlling a press machine (30) having a servo motor (41) to drive a slide (38) via a reduction mechanism (37) changed in reduction ratio in accordance with the position of the slide (38) is disclosed. The device includes a command generator (20) for generating at least one of a position command, a speed command and a torque command for the servo motor (41); a vibration command generator (13) for generating a vibration command based on a parameter preset for the press machine controller (10); a slide position detector (12) for detecting the position of the slide (38); and a vibration command adding portion (21, 22, 23) for adding the vibration command to any one of the position command, the speed command and the torque command for the servo motor (41) in the case where the slide position is in a predetermined range. The press machine, even if stopped with the slide at the bottom dead center, can be restarted with a small torque.

Abstract: A die cushion controller, for driving a die cushion, disposed in opposition to a slide of a press machine, by controlling a servo motor, including: a pressure command portion which prepares a pressure command value for exerting a predetermined pressure to a press material disposed between the slide and the die cushion; a pressure detecting portion which detects an actual pressure exerted on the press material; a speed correction value preparing portion which prepares a speed correction value by multiplying a differential value of the pressure command value prepared by the pressure command portion by a coefficient; and a first speed command portion which prepares a speed command value to be instructed to the servo motor based on the pressure command value prepared by the pressure command portion, the actual pressure detected by the pressure detecting portion, and the speed correction value prepared by the speed correction value preparing portion.

Abstract: A device for controlling a feed motion of a feed control axis and a rotary motion of a rotary control axis, both axes being provided in a machine tool so that the rotary control axis is fed along the feed control axis. The device includes an interference estimating section estimating an interference generated between the feed control axis and the rotary control axis, based on a position command instructed to at least one of the feed control axis and the rotary control axis and a position and mass information of an eccentric load carried by the rotary control axis; and a command correcting section correcting a current command given to at least one of the feed control axis and the rotary control axis, based on the interference estimated by the interference estimating section.