JP2006031146A - Numerical control device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a numerical control device which quickly responds while restraining oscillation relating to a motor and an object to be controlled. <P>SOLUTION: The numerical control device is provided with; a filter part 3 that issues a moving command to a filter, which has not only characteristics that reduce the gains of a prescribed frequency and its vicinal frequency but also characteristics that restrain gain of high frequency area, to output the command as a servo amplifier command; a display means 5 which can display the moving command and the servo amplifier command; and an input means 6 which enables an operator to change speed-acceleration time or speed-reduction time for the moving command. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a numerical control device that controls a drive mechanism so as to operate a movable portion based on numerical data indicating the operation of the movable portion or the drive mechanism, and in particular, a technique for suppressing vibration of a device including the movable portion. About.

  Conventionally, in positioning control using an electric motor, digital servo control using a microcomputer has been performed, and a vibration damping device for an electric motor for the purpose of vibration suppression has been disclosed (for example, Patent Document 1).

In FIG. 5, by inserting the filter unit 3 having the configuration shown in FIG. 7, the vibration of the controlled object 13 is changed to a command pattern that does not excite, and the vibration of the controlled object is suppressed. The filter unit 3 calculates a vibration suppression compensation value obtained by second-order differentiation of the position command θ * and multiplying by a predetermined coefficient 1 / (ωa ² ). Here, ωa is calculated from ωa = 2π · fa where the vibration frequency to be controlled is fa.

  As can be seen from the frequency characteristic diagram of the transfer function from the position command θ * to the control target position θL (FIG. 6), the filter unit 3 reduces the gain of the frequency near the vibration frequency fa of the control target 13 from the command pattern. It is a thing.

  Further, in Patent Document 1, in order to avoid the influence of the torque limit due to the change of the command pattern due to the influence of the filter section 3 and the occurrence of the acceleration fluctuation point, the filter section 3 is configured as shown in FIG. However, due to the influence of the secondary filter, θM * (solid line) which is the output of the filter unit with respect to θ * (dotted line) of the filter unit input as shown in FIG. The change end point of is delayed. In other words, there was a problem that the response was delayed.

As a solution to this problem, a method of changing ωf with time is proposed, but it cannot cope with a change in the command pattern. Moreover, although it is said in Patent Document 1 that the filter 18 may be included in the position command generation means 1, there is no specific description.
JP 2004-5469 A

  The problem to be solved is that the response is delayed by adding a filter having both a characteristic for lowering the gain of a predetermined frequency and its neighboring frequencies and a characteristic for suppressing the gain of the high frequency band.

  Further, this is a frequency setting method for suppressing vibration when a filter is placed in the position command creating unit.

  The present invention solves the above-described conventional problems, and an object thereof is to provide a numerical control device that speeds up the response while suppressing vibrations related to the electric motor and the controlled object.

In order to solve the above-described problems, the present invention causes the movement command to act on a filter having both a characteristic for lowering the gain of a predetermined frequency and the frequency in the vicinity thereof and a characteristic for suppressing a high-frequency gain, and outputs it as a servo amplifier command A numerical control device comprising a filter, display means capable of displaying the movement command and the servo amplifier command, and input means capable of changing an acceleration or deceleration time of the movement command by an operator. It is possible for the person to confirm the delay by the movement command filter and to accelerate the acceleration / deceleration time, thereby speeding up the response.

  According to the numerical control device of the present invention, a command is given to the servo amplifier by inserting a filter having a characteristic of lowering the gain of a predetermined frequency and a frequency in the vicinity thereof and a characteristic of suppressing the gain of the high frequency in the command generation means. Since the delay due to the filter can be calculated before output, the acceleration and deceleration times can be adjusted in consideration of the delay, and the response can be accelerated.

  Further, by enabling communication with the servo amplifier, a predetermined frequency setting value can be set from the servo amplifier, so that a means for inputting a predetermined frequency on the command creating means side can be eliminated.

  In a numerical control device that generates a movement command by a command generation means and outputs it to a servo amplifier, the movement command is applied to a filter having both a characteristic for lowering a gain at a predetermined frequency and a frequency in the vicinity thereof and a characteristic for suppressing a high-frequency gain. A filter for outputting as a servo amplifier command, a display means for displaying the movement command and the servo amplifier command, and an input means for allowing an operator to change the acceleration or deceleration time of the movement command. It is a numerical control device.

  In FIG. 1, 1 is a position command generating means, 2 is a position command creating section, 3 is a filter section, 4 is a position command output section, 5 is a display means, 6 is an input means, 7 is a servo amplifier, and a filter section 3 Is the same as the configuration shown in FIG.

  A servo motor is connected to the servo amplifier 7 and a control target is connected to the servo motor, but the description is omitted here. The position command creating unit 2 and the filter unit 3 are configured by a program using a microcomputer.

  First, when the position command θ * created by the position command creation unit 2 is applied to the filter unit 3, the servo amplifier command θM *, which is the output of the filter unit 3, becomes as shown in FIG. 9, and a gain of a predetermined frequency ωa is obtained. By lowering, the vibration of the controlled object can be reduced. The servo amplifier command θM * is output from the position command output unit 4 to the servo amplifier 7. The pattern shown in FIG. 9 can be confirmed by the display means 5.

  Next, the operator uses the input unit 6 to input the acceleration / deceleration time of the position command pattern so as to be advanced as in the servo amplifier command θ * shown in FIG. As a result, the acceleration time of θM * can be advanced and the response can be accelerated.

  The input unit 6 may be performed by communication or the like. Further, although the first embodiment has been described with respect to the position command, it may be a speed command.

  A second embodiment will be described with reference to FIG. About the same block as Example 1, the description is abbreviate | omitted using the same code | symbol.

First, since the position command generation means 1 outputs what position command pattern from the position command creation unit 2 and the configuration of the filter unit 3 are known, the servo amplifier position command θ * shown in FIG. It is possible to calculate in advance what pattern the servo amplifier command θM * will be when the filter unit 3 is applied to a simple position command pattern.

  9 is obtained in advance and the slope of the dotted line shown in FIG. 4 is automatically changed so that the solid line shown in FIG. 4 becomes the slope of the dotted line shown in FIG. Can be expedited. Note that the slope of the solid line can be easily obtained by using the least square method or the like.

  By the way, it is thought that the slope of the dotted line may be steep from the beginning regardless of the action of the filter unit 3, but the minimum acceleration / deceleration of the command pattern depends on the normal load, the strength of the driving machine, or the performance of the servo amplifier Since the time is determined, the inclination of the position command θ * cannot be determined appropriately.

  A third embodiment will be described with reference to FIG. About the same block as Example 1, the description is abbreviate | omitted using the same code | symbol.

  The servo amplifier 7 and the position command generation means 1 can exchange parameters by the communication means 8. On the other hand, it is necessary to set the vibration frequency fa (ωa) to be controlled in the filter unit 3.

  Therefore, using the communication means 8 enables setting from the servo amplifier 7 and eliminates the need for an input means for the position command generating means 1 as in the first embodiment.

  The numerical control device of the present invention is suitable for suppressing vibration of a device that controls the drive mechanism so as to operate the movable portion based on numerical data indicating the operation of the movable portion or the drive mechanism.

1 is a block diagram of a numerical control device according to a first embodiment of the present invention. The block diagram of the numerical control apparatus in Example 2 of this invention The block diagram of the numerical control apparatus in Example 3 of this invention Waveform diagram of position command θ * and servo amplifier command θM * in the first and second embodiments of the present invention Control block diagram of conventional motor control device Frequency characteristic diagram of transfer function from position command θ * to control target position θL in the conventional example Configuration diagram of filter unit in conventional example Another configuration diagram of the filter unit in the conventional example Waveform diagram of position command θ * and servo amplifier command θM * in the conventional example

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Position command production | generation means 2 Position command creation part 3 Filter part 4 Position command output part 5 Display means 6 Input means 7 Servo amplifier 8 Communication means 13 Control object

Claims (3)

In a numerical control device that generates a movement command by a command generation means and outputs it to a servo amplifier, the movement command is applied to a filter having both a characteristic for lowering a gain at a predetermined frequency and a frequency in the vicinity thereof and a characteristic for suppressing a high-frequency gain. A filter for outputting as a servo amplifier command, a display means for displaying the movement command and the servo amplifier command, and an input means for allowing an operator to change the acceleration or deceleration time of the movement command. Numerical control unit. In a numerical control device that generates a movement command by a command generation means and outputs it to a servo amplifier, the movement command is applied to a filter having both a characteristic for lowering a gain at a predetermined frequency and a frequency in the vicinity thereof and a characteristic for suppressing a high-frequency gain. And a command generating means for automatically accelerating the acceleration or deceleration time of the movement command when the servo amplifier command is delayed with respect to the movement command. The numerical control apparatus according to claim 1, further comprising a communication unit that communicates with the servo amplifier, wherein the predetermined frequency of the filter can be set from the servo amplifier by the communication unit.