KR101514147B1 - Chatter vibration control method of machine tool using destructive interference effects and apparatus thereof - Google Patents

Abstract

An embodiment of the present invention relates to a method and an apparatus to control chatter vibration of a machine tool using destructive interference effects. A technical problem to be solved is to provide the method and apparatus to control the chatter vibration of the machine tool using the effects of destructive interference capable of improving the accuracy and roughness of a processed product by suppressing the chatter vibration which has the greatest effect on the processing quality among vibrations generated when processing a raw material in the machine tool. To achieve this, the present invention comprises: a sensing step which senses a chatter vibration signal of the machine tool; a signal analyzing and generating step which generates a control signal to suppress the chatter vibration by analyzing the chatter vibration signal obtained from the sensing step; and an excitation step which excites the machine tool using the control signal obtained from the signal analyzing and generating step.

Description

[0001] The present invention relates to a method and apparatus for controlling chatter vibration of a machine tool using destructive interference effects,

One embodiment of the present invention relates to a method and apparatus for controlling chatter vibration of a machine tool using a destructive interference effect. Particularly, the present invention relates to a machine tool using a destructive interference effect that can improve chatter vibrations, which have the greatest influence on machining quality, among vibrations generated when machining a workpiece in a machine tool, And a method of controlling the chatter vibration of the chatter vibration.

Generally, in a machine tool in which a tool is attached to a rotating main shaft to machine the workpiece, bending due to cutting resistance is likely to occur in the tool or the workpiece. And, due to this bending, vibration is caused in the machining tool and the workpiece. This vibration may be chattering (including chattering) and appearing in machining.

In order to suppress the above-described chattering, in the conventional technique, a vibration signal generated during machining and non-machining is acquired and it is judged whether or not the vibration signal is chatter vibration and a method of changing the rotation number (RPM) . (See Japanese Patent Laid-Open No. 2007-44852)

1A and 1B, a method for suppressing chattering in a conventional technique includes a step S2 of detecting vibration generated when the rotation of the tool is started, and a step S2 for detecting the vibration, (S4 to S20), the vibration is analyzed by the Fourier series expansion, and when it is judged that the vibration exceeds the limit value, the vibration is analyzed by the Fourier series expansion (S4 to S20) (Step S21).

In the method and apparatus for suppressing chattering of a machine tool according to the above method, vibration is detected from the start of rotation and the vibration is analyzed by Fourier series expansion. The Fourier series expansion improves the immediacy because the calculation is simple and quick, and chattering vibration can be predicted before chattering actually occurs.

Therefore, it becomes possible to anticipate regenerative chattering in which vibration starts from zero with the start of rotation as early as possible. Thereby, before the influence by the chattering actually occurs, the number of revolutions of the machine main shaft can be adjusted, thereby suppressing the occurrence of regeneration chattering.

In the conventional method, a power spectrum of the collected vibration signal is scanned at intervals of 10 Hz by a remedy method for determining chattering vibration, and a search (S6) is performed to retrieve a peak value therefrom. If it is judged that there is a peak value, a predetermined search (S8) is performed by scanning several tens Hz before and after the retrieved peak value every 1 Hz. The frequency of the fundamental wave is compared with the frequency of the fundamental wave by the number of rotations and the number of the blades. And determines the number of rotations of the main shaft from the equation of frequency x 60 / blade count.

As shown in FIG. 2, the controller of the conventional chatter vibration suppression apparatus has a structure in which a vibration detector is attached to a machine tool, a vibration signal is input, a controller processes the vibration signal, and a chatter suppression signal is output to the machine tool control device.

The vibration detector consists of an acceleration sensor and a microphone that acquires a sound wave. The signal collected by the detector is transmitted to the chattering suppression computation unit via the amplifier and the filtering circuit. The controller system is provided with a machining condition input unit for inputting the number of blades and the number of revolutions of the machining tool and includes a display unit capable of informing the user of the change in the number of revolutions for suppressing chatter vibration, And an output unit for outputting the limit unit and the revolution number update value to the machine tool control device.

3 shows the position where the vibration acceleration sensor is attached to the machine tool and the approximate position of the microphone for collecting the sound signal, and shows the flow of the rotation speed update signal to the chatter suppression control unit and the machine tool control device .

The biggest problem in the prior art is to change the rotational speed of the main shaft during machining to avoid chatter.

The rotational speed of the main spindle is determined by the user in consideration of the machining quality, conditions, and productivity. When the chatter control is performed by the conventional method, the speed of the main spindle set by the user is ignored, do.

However, if the rotational speed is forcibly changed at a speed lower than the set value set by the user, the productivity is adversely affected due to an increase in the cycle time . On the contrary, when the speed is forcibly changed at a speed higher than the set value, it is highly likely that the speed is set higher than the critical speed of the main shaft. In this case, the chatter avoiding effect can not be obtained.

Further, in a special processing condition in which the main shaft rotation speed can not be changed, a conventional method of avoiding chatter by changing the main shaft rotation speed can not be used.

One of the problems in changing the rotational speed during machining is that the insert wear of the tool is widespread and irregular rather than machining at a constant speed. This makes it difficult to predict the tool life and makes it difficult to set the tool change timing. If tool replacement is not carried out at an appropriate point in machine tool operation, defects in workpieces will increase, leading to deterioration in productivity.

Japanese Patent Application Laid-Open No. 2007-044852 (February 22, 2007)

One embodiment of the present invention is a method of suppressing chatter vibration which has the greatest influence on the machining quality among vibrations generated when machining a workpiece in a machine tool, and using the destructive interference effect capable of improving the precision and roughness of the workpiece A method of controlling chatter vibration of a machine tool and a device therefor are provided.

A method of controlling chatter vibration of a machine tool using a destructive interference effect according to an embodiment of the present invention includes sensing a chatter vibration signal of a machine tool; A signal analysis and generation step of generating a suppression signal for chatter vibration suppression by analyzing the chatter vibration signal obtained in the sensing step; And an excitation step of exciting the machine tool using the suppression signal obtained in the signal analysis and generation step.

The exciting step may provide the same excitation signal as the chatter oscillation signal to the machine tool, wherein the phase angle of the excitation signal may be 180 degrees different from the chatter oscillation signal.

Wherein the signal analysis and generation step comprises: a filtering step of passing only a frequency region that can be analyzed in the chatter vibration signal; An analog-to-digital conversion step of converting the filtered signal into a digital signal; A Fourier transform analysis step of performing Fourier transform analysis on the digital signal; A chatter vibration detecting step of detecting a frequency and a magnitude of the chatter frequency using the Fourier transform-analyzed signal; A phase control step of generating an excitation signal having the same frequency and magnitude as the chatter frequency and having a phase difference of 180 degrees so that the chatter vibration is canceled; And a digital-to-analog conversion step of converting the excitation signal having a phase difference of 180 degrees obtained from the phase control step into an analog signal. Wherein the chatter vibration detection step includes a step of detecting a chatter vibration of the machine tool, the vibration amplitude of which is larger than a preset value among vibration components of a frequency band excluding a vibration unbalance frequency caused by a mechanical element reflected at a design, As a chattering component.

In the sensing step, the sensor may be attached to the main shaft of the machine tool and the tool table or table to sense the vibration acceleration.

The exciter in the exciting step may provide a signal attached to the spindle, table or tool rest of the machine tool.

An apparatus for controlling chatter vibration of a machine tool using a destructive interference effect according to an embodiment of the present invention includes a sensing unit sensing a chatter vibration signal of a machine tool; A signal analysis and generation unit for analyzing the chatter vibration signal obtained by the sensing unit to generate a suppression signal for chatter vibration suppression; And an excitation unit for exciting the machine tool using the suppression signal obtained from the signal analysis and generation unit.

The excitation unit may provide the same excitation signal as the chatter oscillation signal to the machine tool, and the phase angle of the excitation signal may be 180 degrees different from the chatter oscillation signal.

Wherein the signal analyzing and generating unit includes: a filtering unit for passing only a frequency region that can be analyzed in the chatter vibration signal; An analog-digital converter for converting the filtered signal into a digital signal; A Fourier transform analysis unit for Fourier transforming and analyzing the digital signal; A chatter vibration detector for detecting the frequency and magnitude of the chatter frequency using the Fourier transform-analyzed signal; A phase controller for generating an excitation signal having the same frequency and magnitude as the chatter frequency and having a phase difference of 180 degrees so that the chatter vibration is canceled; And a digital-analog converter for converting the excitation signal having a phase difference of 180 degrees obtained from the phase controller into an analog signal. The chatter vibration detecting unit may increase the vibration magnitude or increase the frequency of the mass unbalance vibration frequency due to the rotational speed of the main shaft of the machine tool or a predetermined value among the vibration components of the frequency band excluding the vibration frequency component caused by the mechanical elements reflected at the design The moving frequency can be determined as a chattering component.

In the sensing unit, the sensor may be attached to the main shaft of the machine tool and the tool table or the table to sense the vibration acceleration.

The vibrating part of the vibrating part may provide a signal attached to the main shaft of the machine tool, the table or the tool rest.

One embodiment of the present invention is a method of suppressing chatter vibration which has the greatest influence on the machining quality among vibrations generated when machining a workpiece in a machine tool, and using the destructive interference effect capable of improving the precision and roughness of the workpiece A method of controlling chatter vibration of a machine tool and a device therefor are provided.

1A and 1B are flowcharts showing a chatter vibration control method of a conventional machine tool.
2 is a block diagram showing a chatter vibration control apparatus of a conventional machine tool.
3 is a schematic view showing an installation position of an acceleration sensor and a microphone in a conventional machine tool.
4 is a block diagram illustrating an apparatus for controlling chatter vibration of a machine tool using a destructive interference effect according to an embodiment of the present invention.
FIG. 5 is a flowchart illustrating a chatter detection method in a method of controlling chatter vibration of a machine tool using a destructive interference effect according to an embodiment of the present invention.
FIG. 6 is a flowchart showing a phase control method in a method of controlling chatter vibration of a machine tool using a destructive interference effect according to an embodiment of the present invention.
FIG. 7 is a flowchart illustrating a control method of a digital-analog converter in a method of controlling chatter vibration of a machine tool using a destructive interference effect according to an embodiment of the present invention.
FIG. 8 is a schematic view showing a configuration of an apparatus for controlling chatter vibration of a machine tool (lathe) using a destructive interference effect according to an embodiment of the present invention.
FIG. 9 is a schematic view showing a configuration of an apparatus for controlling chatter vibration of a machine tool (milling) using a destructive interference effect according to an embodiment of the present invention.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

The embodiments of the present invention are described in order to more fully explain the present invention to those skilled in the art, and the following embodiments may be modified into various other forms, The present invention is not limited to the embodiment. Rather, these embodiments are provided so that this disclosure will be more faithful and complete, and will fully convey the scope of the invention to those skilled in the art.

In the following drawings, thickness and size of each layer are exaggerated for convenience and clarity of description, and the same reference numerals denote the same elements in the drawings. As used herein, the term "and / or" includes any and all combinations of one or more of the listed items.

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used herein, the singular forms "a," "an," and "the" include singular forms unless the context clearly dictates otherwise. Also, " comprise "and / or" comprising "when used herein should be interpreted as specifying the presence of stated shapes, numbers, steps, operations, elements, elements, and / And does not preclude the presence or addition of one or more other features, integers, operations, elements, elements, and / or groups.

Although the terms first, second, etc. are used herein to describe various elements, components, regions, layers and / or portions, these members, components, regions, layers and / It is obvious that no. These terms are only used to distinguish one member, component, region, layer or section from another region, layer or section. Thus, a first member, component, region, layer or section described below may refer to a second member, component, region, layer or section without departing from the teachings of the present invention.

4 is a block diagram illustrating an apparatus for controlling chatter vibration of a machine tool using a destructive interference effect according to an embodiment of the present invention.

In a machine tool rotating at a high speed, vibration due to a cutting force generated during tooling or material processing is likely to occur, and this vibration grows as recycling chattering, which causes continuous vibration during material processing.

Accordingly, as shown in FIG. 4, an apparatus 100 for controlling chatter vibration of a machine tool using a destructive interference effect according to the present invention includes a sensing unit 110 for sensing a chatter vibration signal of a machine tool; A signal analysis and generation unit 120 for analyzing the chatter vibration signal obtained by the sensing unit 110 to generate a suppression signal for chatter vibration suppression; And an excitation unit 130 for exciting the machine tool using the suppression signal obtained from the signal analysis and generation unit 120. [ That is, the present invention forcibly inputs a vibration equal to the chatter vibration frequency to a tool or a work, the phase angle of which is different by 180 degrees, and the amplitude of the chatter vibration is reduced or eliminated by the destructive interference effect. The construction and operation of the present invention will be described in more detail.

The sensing unit 110 includes a sensor 111 for sensing the chatter vibration signal of the machine tool as described above. The sensor 111 is attached to the main shaft of the machine tool and the tool rest and / or the table to sense the vibration acceleration. In addition, the mounting position of the sensor 111 is not limited to the above-described position, and the sensor 111 can be installed at a position where the most reliable vibration signal can be collected according to the shape of the machine tool.

The signal analysis and generation unit 120 analyzes the chatter vibration signal obtained from the sensing unit 110 and generates a suppression signal for chatter vibration suppression. The signal analysis and generation unit 120 may be referred to as a DSP (Digital Signal Processor) board.

The signal analysis and generation unit 120 includes a filtering unit 121, an analog-digital conversion unit 122, a Fourier transform analysis unit 123, a chatter vibration detection unit 124, a phase control unit 126, (125).

The filtering unit 121 allows only the frequency domain of the chatter vibration signal obtained from the sensor 111 to pass through. Here, the chatter vibration signal is an analog signal.

The analog-to-digital converter 122 converts the filtered signal obtained by the filtering unit 121 into a digital signal and outputs the digital signal. The analog-to-digital converter 122 has a predetermined resolution and a sampling rate, and quantizes the filtered chatter vibration signal.

The Fourier transform analysis unit 123 performs fast Fourier transform on the digital signal obtained from the analog-to-digital converter 122 and analyzes it. Here, the Fourier transform-analyzed signal is transmitted to the chatter vibration detection unit 124 and the digital-analog conversion unit 125, respectively.

Here, the operations from the sensor 111 to the Fourier transform analysis unit 123 are performed in real time.

The chatter vibration detecting unit 124 detects the chatter frequency (frequency) and the magnitude using the Fourier transform-analyzed signal. That is, the chatter vibration detection unit 124 detects the vibration amplitude of the vibration amplitude component of the vibration amplitude component of the vibration component of the frequency band excluding the vibration component of the mass unbalanced vibration due to the mechanical element reflected at the design and / Or a frequency at which the frequency moves is determined as a chattering component and detected. Here, the frequency determined as a chattering component may be one or more. In addition, the value and magnitude of the detected frequency are transmitted to the phase controller 126. The operation of the chatter vibration detector 124 is shown in FIG. 5, which will be described in more detail below.

The phase control unit 126 generates and outputs an excitation signal (suppression signal) equal to the frequency and magnitude of the chatter frequency described above so that the chatter vibration is canceled, and the phase difference is 180 degrees. For example, a time delay of 180 degrees of phase difference is inserted into a fundamental sinusoidal signal to produce a data stream having a complete period, which data sequence has a continuous digital value As shown in FIG. The operation of this phase control unit 126 is shown in Figure 6, which is described in more detail below.

The digital-to-analog converter 125 converts the excitation signal having the phase difference of 180 degrees obtained from the phase controller 126 into an analog signal, and outputs the analog signal to the exciter 130. [ Here, the signal analysis and generation unit 120 compares the pre- and post-output values of the output from the digital-analog converter 125 using the results of the pre-conversion analysis input to the chatter vibration detection unit 124 as a feedback, So that control is performed in the control loop. The operation of the digital-to-analog converter 125 is shown in FIG. 7, which will be described in more detail below.

The excitation unit 130 excites the machine tool using the suppression signal obtained from the signal analysis and generation unit 120, thereby eliminating the chatter vibration. That is, the excitation unit 130 provides the same excitation signal as the chatter oscillation signal to the machine tool, so that the phase angle of the excitation signal is 180 degrees different from the chatter oscillation signal. Substantially, this excitation 130 includes an amplifier 131 and a exciter 132 which amplifies the suppression signal and exciter 132 actually energizes the machine tool. The machine 132 in the exciter 130 may provide a signal attached to the spindle, table, and / or tool rest of a machine tool (lathe, mill). In addition, as necessary, the exciter 132 is attached to the table of the tool or milling of the lathe, causing destructive interference by the excitation frequency having a 180 degree phase difference, thereby reducing or eliminating chatter vibrations.

FIG. 5 is a flowchart illustrating a chatter detection method in a method of controlling chatter vibration of a machine tool using a destructive interference effect according to an embodiment of the present invention.

The chatter vibration detection unit 124 receives Fourier transform analysis results at intervals of 1 Hz, for example, and searches for all peak frequencies.

In addition, the chatter vibration detection unit 124 determines whether there is an unknown frequency among the peak frequencies. The chatter vibration detector 124 tracks this unknown frequency if there is an unknown frequency.

The chatter vibration detection unit 124 determines whether the unknown frequency magnitude increases. If the magnitude of the unknown frequency is large, the chatter vibration detector 124 determines that chatter vibration exists, and if the unknown frequency does not increase in size, the unknown frequency shifts beyond the error range of the Fourier transform analysis range . If the unknown frequency shifts beyond the error range of the Fourier transform analysis range, the chatter vibration detecting section 124 determines that chatter vibration exists.

The chatter vibration detection unit 124 determines whether there is a drain component (i.e., harmonic) in frequency, and deletes the drain component if there is a drain component. The chatter vibration detection unit 124 transmits the frequency value and the magnitude to the phase control unit 126. If there is no drain component in the frequency, the chatter vibration detector 124 transmits the frequency value and the magnitude to the phase controller 126 as it is, as described above.

FIG. 6 is a flowchart showing a phase control method in a method of controlling chatter vibration of a machine tool using a destructive interference effect according to an embodiment of the present invention.

The phase control unit 126 determines whether the input frequency is equal to or more than 1, and if the frequency is equal to or more than 1, the phase control unit 126 calculates n delay times (delay time) ). Further, the phase control unit 126 generates n sinusoidal waveforms by Y = A sin (t). The phase control unit 126 shifts each sinusoidal waveform by the calculated delay time and sums the shifted n sinusoidal waves to generate a data stream. Further, the phase control section 126 transmits the above-described data stream to the digital-analog conversion section 125. [ Here, n is a natural number, Y is a signal value, A is amplitude, ω is angular frequency, and t is time.

In addition, if the input frequency is not more than one, the phase control unit 126 generates a data stream by Y = A sin (t). In addition, the phase control unit 126 calculates n delay times to make a phase difference of 180 degrees by a formula of? = 1 / f. In addition, the phase control unit 126 transmits the delay time and the data stream to the digital-analog converter 125

FIG. 7 is a flowchart illustrating a control method of a digital-analog converter in a method of controlling chatter vibration of a machine tool using a destructive interference effect according to an embodiment of the present invention.

The digital-to-analog converter 125 determines whether there is delay time information from the signal or information received from the phase controller 126.

The digital-analog converter 125 receives the Fourier transform analysis value from the Fourier transform analysis unit 123 before outputting the suppression signal, and outputs the suppression signal by applying the delay time described above.

Also, the digital-analog converter 125 receives the Fourier transform analysis value from the Fourier transform analysis unit 123 after outputting the suppression signal, and determines whether the frequency magnitude before and after the output is equal to or less than a preset reference value.

The digital-to-analog converter 125 maintains the output when the frequency magnitude before and after the output is equal to or less than a preset reference value, and changes the delay time when the magnitude of the frequency before and after the output does not fall below the reference value, And returns to the step of receiving the output full Fourier transform analysis value by the FFT analyzing unit 125.

On the other hand, if there is no delay time information, the digital-analog converter 125 stores the above-described data stream arrangement in a memory. Then, the digital-analog converter 125 receives the Fourier transform analysis value from the output pre-Fourier transform analysis unit 123, and the memory outputs the data stream array to the digital-analog converter 125. The digital-analog converter 125 receives the Fourier transform analysis value from the Fourier transform analysis unit 123 after the output. In addition, the digital-analog converter 125 maintains the output when the frequency magnitude before and after the output is less than the reference value, and when the magnitude of the frequency before and after the output does not fall below the reference value, And returns to the step of judging whether or not it exists.

FIG. 8 is a schematic view showing a configuration of an apparatus for controlling chatter vibration of a machine tool (lathe) using a destructive interference effect according to an embodiment of the present invention.

As shown in Fig. 8, a machine tool (lathe) is connected to a main shaft of a motor, a workpiece is coupled to the main shaft, a pressure ball is coupled to one side of the workpiece, and a tool bar is positioned on the other side of the workpiece. Here, the sensor 111 described above may be installed in a motor, a main shaft, a tailstock, etc., and the vibrator 132 capable of vibrating in three axes may be installed on a main shaft, a tool stand, or the like. Of course, the signal from the sensor 111 is transmitted to the signal analysis and generation unit 120 (DSP board), and the exciter 132 is connected to the amplifier 131 connected to the signal analysis and generation unit 120, . Also, the signal analysis and generation unit 120 is controlled by the machine tool control unit.

FIG. 9 is a schematic view showing a configuration of an apparatus for controlling chatter vibration of a machine tool (milling) using a destructive interference effect according to an embodiment of the present invention.

As shown in Fig. 9, a machine tool (milling) is connected to a motor with a main shaft, a tool bar is connected to the main shaft, and a workpiece is placed on the table. Here, the sensor 111 may be installed in a motor, a main shaft, a table, etc., and the vibrator 132 capable of vibrating in three axes may be installed on a main shaft, a table, or the like. Of course, the signal from the sensor 111 is transmitted to the signal analysis and generation unit 120 (DSP board), and the exciter 132 is connected to the amplifier 131 connected to the signal analysis and generation unit 120, . Also, the signal analysis and generation unit 120 is controlled by the machine tool control unit.

In this way, the present invention improves the quality of the machine tool product and improves the productivity of the machine tool.

From the viewpoint of quality improvement, the present invention can improve the quality of workpieces without changing the cycle time under the machining conditions in which the spindle rotational speed can not be changed by chatter vibration control which does not require the change of the spindle rotational speed during machining.

Also, in terms of productivity improvement, the present invention can fundamentally eliminate the increase in machining time that occurs when the spindle rotational speed is lowered during chatter avoidance, which is one of the problems in the prior art.

Further, since the number of spindle revolutions does not change during machining, the present invention can reduce the wide and irregular wear of the machining tool, thereby setting a quantitative tool change period, which leads to an improvement in the productivity of the machine tool.

The present invention is not limited to the above-described embodiment, but may be applied to a method of controlling chatter vibration of a machine tool using the destructive interference effect according to the present invention, It will be understood by those of ordinary skill in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined in the appended claims.

100; A control device for chatter vibration of a machine tool according to the present invention
110; A sensing unit 111; sensor
120; A signal analysis and generation unit 121; The filtering unit
122; An analog-to-digital converter 123; Fourier transform analysis section
124; Chatter vibration detection unit 125; The digital-
126; A phase control unit 130; An exciting part
131; Amplifier 132; Exciter

Claims (12)

Sensing a chatter vibration signal of the machine tool;
A signal analysis and generation step of generating a suppression signal for chatter vibration suppression by analyzing the chatter vibration signal obtained in the sensing step; And
And an excitation step of exciting the machine tool using the suppression signal obtained in the signal analysis and generation step,
Wherein the signal analysis and generation step comprises: a filtering step of passing only the analyzable frequency region of the chatter vibration signal; An analog-to-digital conversion step of converting the filtered signal into a digital signal; A Fourier transform analysis step of performing Fourier transform analysis on the digital signal; A chatter vibration detecting step of detecting a frequency and a magnitude of the chatter frequency using the Fourier transform-analyzed signal;
A phase control step of generating an excitation signal having the same frequency and magnitude as the chatter frequency and having a phase difference of 180 degrees so that the chatter vibration is canceled; And
And a digital-to-analog conversion step of converting the excitation signal having a phase difference of 180 degrees obtained from the phase control step into an analog signal,
If the frequency inputted in the phase control step is 1 or more, n delay times that make a phase difference by τ (delay time) = 1 / f (frequency) are calculated, and n is calculated by Y = A · sin (ωt) And generates a data stream by summing the shifted n sine waves (where n is a natural number and Y is a natural number), and generates a data stream by shifting each sine wave type by the calculated delay time, Signal value, A is amplitude, ω is angular frequency, t is time)
Wherein when the delay time information is present from the data stream in the digital-analog conversion step, the Fourier transform analysis value is input before the suppression signal is output, and the suppression signal is output by applying the delay time. Control method. The method according to claim 1,
Wherein the energizing step provides the machine tool with the same excitation signal as the chatter vibration signal, wherein the phase angle of the excitation signal is 180 degrees different from the chatter vibration signal. delete The method according to claim 1,
The chatter vibration detection step
A frequency at which the vibration magnitude increases or the frequency shifts more than a preset value among the vibration components of the frequency band excluding the vibration unbalance frequency due to the machine element reflected at the design or the vibration component due to the rotation speed of the main shaft of the machine tool, Ring component,
Searching for all peak frequencies and tracking the unknown frequency if there is an unknown frequency among the peak frequencies and if the unknown frequency is becoming larger or the unknown frequency is above the error range of the Fourier transform analysis range If it moves, it is judged as a chattering component,
And if there is a drain component at the frequency, the drain component is deleted. The method according to claim 1,
Wherein the sensor is attached to a main shaft of a machine tool and a tool table or a table in the sensing step to sense a vibration acceleration of the machine tool. The method according to claim 1,
Wherein the vibrator in the vibrating step provides a signal attached to a spindle, a table, or a tool bar of the machine tool. A sensing unit sensing a chatter vibration signal of the machine tool;
A signal analysis and generation unit for analyzing the chatter vibration signal obtained by the sensing unit to generate a suppression signal for chatter vibration suppression; And
And an excitation unit for exciting the machine tool using the suppression signal obtained from the signal analysis and generation unit,
Wherein the signal analyzing and generating unit includes: a filtering unit for passing only a frequency region that can be analyzed in the chatter vibration signal; An analog-digital converter for converting the filtered signal into a digital signal; A Fourier transform analysis unit for Fourier transforming and analyzing the digital signal; A chatter vibration detector for detecting the frequency and magnitude of the chatter frequency using the Fourier transform-analyzed signal; A phase controller for generating an excitation signal having the same frequency and magnitude as the chatter frequency and having a phase difference of 180 degrees so that the chatter vibration is canceled; And a digital-analog converter for converting the excitation signal having a phase difference of 180 degrees, obtained from the phase controller, into an analog signal,
The phase control unit calculates n delay times that make a phase difference by τ (delay time) = 1 / f (frequency) when the input frequency is one or more, and calculates n delay times by Y = A · sin (ωt) Generates a sinusoidal waveform, shifts each sinusoidal waveform by the calculated delay time, and sifts the shifted n sinusoidal waves to generate a data stream (where n is a natural number and Y is a natural number, Value, A is amplitude, ω is angular frequency, t is time)
Wherein the digital-to-analog converter receives the Fourier transform analysis value before the suppression signal is output if there is delay time information from the data stream, and outputs the suppression signal by applying the delay time. Device. 8. The method of claim 7,
Wherein the excitation unit provides the excitation signal equal to the chatter vibration signal to the machine tool, wherein the phase angle of the excitation signal is 180 degrees different from the chatter vibration signal. delete 8. The method of claim 7,
The chatter vibration detecting unit
A frequency at which the vibration magnitude increases or the frequency shifts more than a preset value among the vibration components of the frequency band excluding the vibration unbalance frequency due to the machine element reflected at the design or the vibration component due to the rotation speed of the main shaft of the machine tool, Ring component,
Searching for all peak frequencies and tracking the unknown frequency if there is an unknown frequency among the peak frequencies and if the unknown frequency is becoming larger or the unknown frequency is above the error range of the Fourier transform analysis range If it moves, it is judged as a chattering component,
And if there is a drain component at the frequency, the drain component is deleted. 8. The method of claim 7,
Wherein the sensor in the sensing unit is attached to a main shaft of a machine tool and a tool table or a table to sense a vibration acceleration of the machine tool. 8. The method of claim 7,
Wherein the vibrating unit provides a signal attached to a spindle of a machine tool, a table, or a tool rest.

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