JP4665634B2 - Vibration absorber - Google Patents

Description

  The present invention relates to a vibration absorbing device, and more particularly, to a vibration absorbing device suitable for use in suppressing vibration of a mechanical device.

  Conventionally, a dynamic vibration absorber using an auxiliary mass is known as a vibration damping device. Such a dynamic vibration absorber suppresses vibration of the main mass by applying the inertial force of the auxiliary mass as a reaction force to the main mass that is the object of vibration suppression. Generally, a dynamic vibration absorber is a passive type having a mechanical spring element and a damping element (damper), and actively controls the spring characteristics and damping characteristics of the dynamic vibration absorber by using the driving force of an actuator. There is an active type that performs vibration control.

Here, the active type dynamic vibration absorber is provided with a sensor that detects at least one state (for example, displacement, speed, acceleration, etc.) of the auxiliary mass, the actuator, and the main mass, and based on the detection signal of the sensor. The actuator is driven so that the dynamic vibration absorber has optimum spring characteristics and damping characteristics to suppress vibration of the main system mass (see, for example, Patent Document 1). As shown in FIG. 10, a conventional adjustment method for an ideal undamped one-degree-of-freedom vibration system includes a mass ratio μ of a dynamic vibration absorber mass m1 and a main mass m0, a main natural frequency ω0, and a dynamic vibration absorber. This is realized by obtaining the optimum value of the spring constant k1 and the optimum value of the dynamic vibration damper damping constant c1 of the dynamic vibration damper mass m1 according to the mass m1.
Japanese Patent No. 3398634

  However, in the above conventional adjustment method, in order to provide an appropriate dynamic vibration absorber, the mass ratio and the natural frequency of the main system are accurately measured, and based on the values, the spring constant and damping constant of the dynamic vibration absorber are measured. However, it is sometimes difficult to measure the mass and natural frequency of the main system. Further, even if each constant is set, conventionally, a method for verifying whether or not the value is an optimum value has not been clear. Furthermore, when there is a change in stiffness or mass due to aging, it is necessary to readjust the mass and natural frequency and readjust the dynamic vibration absorber, especially depending on the installation location and posture of the main system. There is also a problem that it is difficult to cope with fluctuations in mass and rigidity.

  Accordingly, the present invention has been made in view of the above-described problems, and provides a vibration absorber capable of automatically accurately estimating the main system natural frequency and automatically adjusting the dynamic vibration absorber spring constant to an optimum value. The purpose is to do.

In order to solve the above-described problems, the present invention proposes the following matters.
The invention according to claim 1 is an actuator that generates thrust between the main system part and the dynamic vibration absorber, a displacement sensor that detects a relative displacement between the main system part and the dynamic vibration absorber, and an absolute acceleration of the main system part. A vibration absorber including an acceleration sensor for detecting the thrust and a control unit for controlling a thrust generated by the actuator, wherein the control unit generates a sinusoidal thrust command, and the displacement A displacement corresponding thrust command generating means for generating a thrust command obtained by multiplying the output of the sensor by a predetermined proportional constant; a speed corresponding thrust command generating means for generating a thrust command proportional to a differential value of the output of the displacement sensor; and the sine A thrust command output means for adding the thrust commands generated from the wave generating means, the displacement corresponding thrust command generating means and the speed corresponding thrust command generating means to output to the actuator, and varying the frequency of the sine wave A wave number varying means, detecting the phase difference between the phase of the sine wave and the signal output from the acceleration sensor, and determining the main system portion from the frequency of the sine wave when the phase difference reaches a predetermined set value. Has proposed a natural frequency estimating means for estimating the natural frequency of the vibration absorbing device.

  According to a second aspect of the present invention, in the vibration absorber according to the first aspect, the predetermined proportionality constant is such that the natural frequency of the dynamic vibration absorber is an upper limit frequency within a range of the natural frequency of the main system portion. There has been proposed a vibration absorbing device characterized in that the dynamic vibration absorber rigidity is such that it is twice or more or half or less of the lower limit frequency.

  According to a third aspect of the present invention, in the vibration absorber according to the second aspect, the natural frequency estimating means is configured such that the phase of the signal output from the acceleration sensor is 90 with respect to the phase of the sine wave. A vibration absorber is proposed in which the frequency of the sine wave is estimated as the natural frequency of the main system portion when it is delayed by 270 degrees or 270 degrees.

  According to these inventions, the sine wave generated by the sine wave generating means and the output of the displacement sensor generated by the displacement corresponding thrust generating means multiplied by a predetermined proportionality constant and the displacement sensor generated by the speed corresponding thrust generating means. The thrust proportional to the output differential value is added by the thrust output means and supplied to the actuator. At this time, the frequency variable means changes the frequency of the sine wave, and the natural frequency estimation means detects the phase difference of the signal output from the acceleration sensor with respect to the phase of the sine wave, and the phase difference is delayed by 90 degrees. Alternatively, the frequency of the sine wave when it is delayed by 270 degrees is estimated as the natural frequency of the main system part. At this time, the proportional constant to be multiplied by the output of the displacement sensor is such that the natural frequency of the dynamic vibration absorber is not less than twice the upper limit frequency of the range of the natural frequency of the main system portion, or 1/2 or less of the lower limit frequency. It is desirable that the dynamic vibration absorber rigidity be such a value.

  According to a fourth aspect of the present invention, in the vibration absorber according to any one of the first to third aspects, the control unit changes the predetermined proportionality constant to change the natural frequency of the dynamic vibration absorber. Obtained from the acceleration sensor by varying the frequency of the sine wave in the vicinity of the estimated natural frequency of the main part obtained by the natural frequency estimating means by the variable natural frequency variable means and the frequency variable means. In the frequency characteristic acquisition means for acquiring the frequency characteristic of the signal, and in the frequency characteristic obtained by the frequency characteristic acquisition means, the predetermined proportionality is set such that the frequency corresponding to the minimum value is the natural frequency of the main system part. A vibration absorber is further provided, which further comprises tuning means for determining a constant.

  According to this invention, the natural frequency of the dynamic vibration absorber is varied by changing the proportionality constant by which the natural frequency variable means multiplies the output of the displacement sensor. The frequency characteristic obtaining unit obtains the frequency characteristic of the signal obtained from the acceleration sensor by changing the frequency of the sine wave in the vicinity of the natural estimated frequency of the main part obtained by the natural frequency estimating unit. Then, the tuning means determines a proportional constant to be multiplied by the output of the displacement sensor so that the frequency corresponding to the minimum value becomes the natural frequency of the main system portion in the obtained frequency characteristics.

  According to a fifth aspect of the present invention, in the vibration absorber according to any one of the first to third aspects, the control unit changes the predetermined proportionality constant to change the natural frequency of the dynamic vibration absorber. Obtained from the acceleration sensor by varying the frequency of the sine wave in the vicinity of the estimated natural frequency of the main part obtained by the natural frequency estimating means by the variable natural frequency variable means and the frequency variable means. A phase difference acquisition means for acquiring a phase difference between the signal and the sine wave; and the phase of the signal obtained from the acceleration sensor is 270 degrees and 90 degrees behind the phase of the sine wave. The storage means for storing the frequency, and the predetermined frequency so as to minimize the difference between the stored frequency of the sine wave when the delay is 270 degrees and the frequency of the sine wave when the delay is 90 degrees. ratio It proposes a vibration absorbing device characterized by further comprising tuning means for determining the constants.

  According to this invention, the natural frequency of the dynamic vibration absorber is varied by changing the proportionality constant by which the natural frequency variable means multiplies the output of the displacement sensor. The phase difference acquisition means changes the frequency of the sine wave in the vicinity of the natural estimated frequency of the main part obtained by the natural frequency estimation means, and acquires the phase difference between the signal obtained from the acceleration sensor and the sine wave. The storage means stores the frequency of the sine wave at which the phase of the signal obtained from the acceleration sensor is delayed by 270 degrees and 90 degrees with respect to the phase of the sine wave. A proportional constant to be multiplied by the output of the displacement sensor is determined so that the frequency difference between the frequency of the sine wave and the frequency of the sine wave with a 90 degree delay is minimized.

  According to a sixth aspect of the present invention, there is provided an actuator that generates a thrust between the main system part and the dynamic vibration absorber, a displacement sensor that detects a relative displacement between the main system part and the dynamic vibration absorber, and an absolute acceleration of the main system part. A vibration absorber including an acceleration sensor for detecting the thrust and a control unit for controlling a thrust generated by the actuator, wherein the control unit generates a sinusoidal thrust command, and the displacement A displacement corresponding thrust command generating means for generating a thrust command proportional to the output of the sensor; a speed corresponding thrust command generating means for generating a thrust command obtained by multiplying a differential value of the output of the displacement sensor by a predetermined proportional constant; and the sine A thrust command output means for adding the thrust commands generated from the wave generating means, the displacement corresponding thrust command generating means and the speed corresponding thrust command generating means to output to the actuator, and varying the frequency of the sine wave A wave number varying means, detecting the phase difference between the phase of the sine wave and the signal output from the acceleration sensor, and determining the main system portion from the frequency of the sine wave when the phase difference reaches a predetermined set value. The natural frequency estimating means for estimating the natural frequency of the vibration, the variable variable means for changing the predetermined proportionality constant to vary the attenuation of the dynamic vibration absorber, and the frequency variable means to change the frequency of the sine wave The frequency characteristic acquisition means for changing the vicinity of the estimated natural frequency of the main system part obtained by the natural frequency estimation means and acquiring the frequency characteristic of the signal obtained from the acceleration sensor, and the curve structure of the frequency characteristic are predetermined. The present invention proposes a vibration absorbing device comprising an attenuation adjusting means for determining the predetermined proportionality constant so as to have an uneven shape.

  The invention according to claim 7 is the vibration absorbing device according to claim 6, wherein the attenuation adjusting unit has a curved structure of frequency characteristics that protrudes downward with the vicinity of the estimated natural frequency of the main system portion as a vertex. A vibration absorbing device is proposed in which the predetermined proportionality constant is determined so as to have a curved structure with an upwardly convex boundary.

  The invention according to claim 8 is the vibration absorbing device according to claim 6, wherein the attenuation adjustment means is such that the curve structure of the frequency characteristics becomes an inflection point in the vicinity of the estimated natural frequency of the main part. A vibration absorber is proposed in which the predetermined proportionality constant is determined.

  According to these inventions, the sine wave generated by the sine wave generating means, the thrust proportional to the output of the displacement sensor generated by the displacement corresponding thrust generating means, and the differential value of the output of the displacement sensor generated by the speed corresponding thrust generating means. The thrust multiplied by a predetermined proportional constant is added by the thrust output means and supplied to the actuator. The frequency variable means varies the frequency of the sine wave, and the natural frequency estimation means detects the phase difference between the phase of the sine wave and the signal output from the acceleration sensor, and the phase difference becomes a predetermined set value. The natural frequency of the main system is estimated from the frequency of the sine wave. The attenuation variable means changes the attenuation of the dynamic vibration absorber by changing a proportional constant that is multiplied by the differential value of the output of the displacement sensor. The frequency characteristic acquisition unit changes the frequency of the sine wave in the vicinity of the natural estimated frequency of the main part obtained by the natural frequency estimation unit, and acquires the frequency characteristic of the signal obtained from the acceleration sensor. Then, the attenuation adjusting means determines a predetermined proportionality constant so that the curve structure of the frequency characteristic has a predetermined uneven shape.

  According to the present invention, the main system natural frequency is automatically estimated accurately, and the dynamic vibration absorber spring constant can be automatically adjusted to the optimum value. Further, according to the present invention, the dynamic vibration absorber can be adjusted even when the mass ratio of the main system and the natural frequency of the main system cannot be measured accurately. In addition, even if stiffness fluctuation or mass fluctuation due to secular change occurs, it is possible to easily set the optimum value by performing automatic adjustment again, and when the mass and rigidity vary depending on the installation location and posture of the main system In this case, there is an effect that it can be coped with by switching to a value that has been automatically adjusted in advance.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
As shown in FIG. 1, the basic configuration of the vibration absorbing device of the present invention includes an actuator 1, a displacement sensor 2, an acceleration sensor 3, a control unit 4, a dynamic vibration absorber mass (m1) 5, and a main mass. (M0) 6, the dynamic vibration absorber mass 5 has mechanical dynamic vibration absorber rigidity and mechanical dynamic vibration absorber damping, and the main mass 6 has main system rigidity and main system damping. Exists. Here, the displacement sensor 2 is a sensor that detects the relative displacement between the dynamic vibration absorber mass 5 and the main system, and the acceleration sensor 3 is a sensor that detects the absolute acceleration of the main system. In addition, since the difference of each embodiment is based on the function of a control part, below, each embodiment is demonstrated in detail focusing on the function of a control part.

<First Embodiment>
As shown in FIG. 2, the control unit according to the present embodiment includes a differentiator 11, an adder (thrust output means) 12, a natural frequency estimation controller (frequency variable means, natural frequency estimation means) 13, , A sine wave oscillator (sine wave generating means) 14, a phase difference detector 15, and a comparator 16.

  The differentiator 11 differentiates the output signal from the displacement sensor 2 and supplies it to the gain term C. The adder 12 gains a gain term C into an output signal obtained by multiplying the output signal from the sine wave oscillator 14, the output signal from the displacement sensor 2 by the gain term K, and a signal obtained by differentiating the output signal from the displacement sensor 2 by the differentiator 11. Is added to the actuator 1 and supplied to the actuator 1. The gain term K determines the rigidity of the electric dynamic vibration absorber, and the gain term C determines the attenuation of the electric dynamic vibration absorber.

  The natural frequency estimation controller 13 controls the sine wave frequency of the sine wave oscillator 14 and estimates the natural frequency of the main system based on the comparison result from the comparator 16. The sine wave oscillator 14 outputs a desired sine wave based on the amplitude command value and the frequency command value given from the natural frequency estimation controller 13 or the like. The phase difference detector 15 detects the phase difference between the output signal from the acceleration sensor 3 and the output signal from the sine wave oscillator 14. The comparator 16 compares the phase difference information output from the phase difference detector 15 with a preset value, and outputs the comparison result to the natural frequency estimation controller 13.

Next, the processing operation in this embodiment will be described.
First, the natural frequency estimation controller 13 designates the frequency of the sine wave to the sine wave oscillator 14. The adder 12 gains an output signal obtained by multiplying the output signal from the sine wave oscillator 14, the output signal from the displacement sensor 2 by the gain term K, and a signal obtained by differentiating the output signal from the displacement sensor 2 by the differentiator 11. The signal multiplied by the term C is added and supplied to the actuator 1.

  Here, the output signal obtained by multiplying the output signal from the displacement sensor 2 by the gain term K becomes the dynamic vibration absorber rigidity combined with the mechanical dynamic vibration absorber rigidity, and the gain term K is adjusted in the positive to negative adjustment range. By doing so, the dynamic vibration absorber rigidity can be controlled. Further, the output signal obtained by multiplying the signal obtained by differentiating the output signal from the displacement sensor 2 by the differentiator 11 by the gain term C becomes the dynamic vibration absorber attenuation combined with the attenuation of the mechanical dynamic vibration absorber. Can be controlled within the positive to negative adjustment range to control the dynamic vibration absorber attenuation.

  The dynamic vibration absorber rigidity is set so that the natural frequency of the dynamic vibration absorber is sufficiently higher or lower than the existence range of the natural frequency of the main system. Specifically, the dynamic vibration absorber rigidity is set such that the natural frequency of the dynamic vibration absorber is greater than or equal to twice the upper limit frequency of the natural frequency range of the main system portion or less than or equal to ½ of the lower limit frequency. It is desirable to set the value to obtain In addition, it is desirable to apply a very small amount of damping to the dynamic vibration absorber so that the vibration of the main system does not become too large.

  The natural frequency estimation controller 13 causes the sine wave oscillator 14 to increase the frequency stepwise from the lower limit value within the range of existence of the main system natural frequency (or stepwise from the upper limit value). Instruct to lower the frequency). At this time, the phase difference detector 15 detects the phase difference between the output signal from the acceleration sensor 3 and the output signal from the sine wave oscillator 14 for each set frequency, and the comparator 16 outputs from the phase difference detector 15. It is detected whether the phase difference information to be delayed is -90 degrees or -270 degrees, and the result is output to the natural frequency estimation controller 13.

  When the natural frequency estimation controller 13 receives a signal indicating that a delay of −90 degrees or −270 degrees is detected from the comparator 16, the natural frequency estimation controller 13 stops the frequency change instruction to the sine wave oscillator 14, and The frequency is estimated as the natural frequency of the main system. Note that the comparison value in the comparator 16 is -90 degrees when the natural frequency of the dynamic vibration absorber is sufficiently higher than the existence range of the natural frequency of the main system, and the natural frequency of the dynamic vibration absorber is Is sufficiently lower than the existence range of the natural frequency of the main system, the delay is -270 degrees.

  FIG. 7 shows calculation examples of the transfer function from the sinusoidal relative excitation force to the main system absolute acceleration when the dynamic vibration absorber natural frequency is sufficiently higher than the main system natural frequency and sufficiently low. Yes. In this figure, the thick line indicates that the dynamic vibration absorber natural frequency is sufficiently higher than the main system natural frequency, and the chain line indicates that the dynamic vibration absorber natural frequency is sufficiently lower than the main system natural frequency. The thin line shows the case of the main system only.

  From this figure, the frequency at which the absolute acceleration of the main system is delayed by 90 degrees or 270 degrees from the relative excitation force is obtained as an estimated value of the main natural frequency. It can be seen that the estimated value when the dynamic vibration absorber natural frequency is increased with respect to 494 kHz is 2.372 kHz, and the estimated value when it is lowered is estimated to be very close to 2.484 kHz. When the natural vibration frequency of the dynamic vibration absorber is lowered, the estimation can be performed with high accuracy based on the true natural frequency of the main system, but the stroke may increase during relative vibration. On the other hand, when the dynamic vibration absorber natural frequency is increased, the estimated value is slightly lower due to the true natural frequency of the main system due to the dynamic vibration absorber mass, but the stroke may be reduced during relative excitation. it can.

<Second Embodiment>
In the present embodiment, the dynamic vibration absorber rigidity is set from the gain characteristics of the absolute acceleration with respect to the frequency. As shown in FIG. 3, the control unit according to the present embodiment includes a differentiator 11, an adder 12, It comprises a sine wave oscillator 14, a stiffness setting controller (natural frequency variable means, frequency characteristic acquisition means, tuning means) 21, an amplitude detector 22, and a differentiator 23. In addition, about the element which attached | subjected the code | symbol same as 1st Embodiment, since it has the same function, description is abbreviate | omitted.

  The stiffness setting controller 21 sets the electrical dynamic vibration absorber stiffness, and sets the frequency for the sine wave oscillator 14 within a frequency range centered on the natural frequency of the main system obtained in the first embodiment. The frequency characteristics of the absolute acceleration of the main system are obtained by variable, and the dynamic vibration absorber rigidity is set so that the main system natural frequency becomes a minimum value. The amplitude detector 22 detects the amplitude of the output of the acceleration sensor 3, and the differentiator 23 differentiates the amplitude detected by the amplitude detector 22 by frequency.

Next, the processing operation in this embodiment will be described.
The stiffness setting controller 21 sets a gain term K as a predetermined electrical dynamic vibration absorber stiffness as an initial value. Next, the frequency for the sine wave oscillator 14 is determined within a frequency range centered on the natural frequency of the main system, and the output signal from the sine wave oscillator 14 and the output signal from the displacement sensor 2 are multiplied by a gain term K. The output signal and the signal obtained by differentiating the output signal from the displacement sensor 2 by the differentiator 11 are added to the signal obtained by multiplying the gain term C and supplied to the actuator 1.

  The output from the acceleration sensor 3 is input to the amplitude detector 22, and the amplitude is detected. The detected amplitude information is differentiated by the differentiator 23 and input to the stiffness setting controller 21. The stiffness setting controller 21 makes a pair of the frequency f given to the sine wave oscillator 14 and dA / df obtained from the differentiator 23 to check whether or not the main system natural frequency is a minimum value, If it is, the previously set gain term K is set as the electric dynamic vibration absorber rigidity. If not, the gain term K is gradually increased or decreased, and the above measurement is continued. The value of the gain term K is determined so as to be a local minimum value.

  FIG. 4 shows a modification of the present embodiment. In the present embodiment, the dynamic vibration absorber rigidity is set from the phase characteristics of the absolute acceleration with respect to the frequency, and the control unit includes a differentiator 11, an adder 12, a sine wave oscillator 14, and the like as shown in FIG. , A phase difference detector 15, a stiffness setting controller (phase difference acquisition means, storage means, tuning means) 31, and comparators 32 and 33. In addition, about the element which attached | subjected the code | symbol same as 1st Embodiment, since it has the same function, description is abbreviate | omitted.

  The stiffness setting controller 31 sets the electrical dynamic vibration absorber stiffness, and sets the frequency for the sine wave oscillator 14 within the frequency range centered on the natural frequency of the main system obtained in the first embodiment. The phase difference of the output waveform from the acceleration sensor 3 with respect to the sine wave output waveform is detected by the phase difference detector 15, and the difference in the frequency of the sine wave frequency at which the phase difference is delayed by 270 degrees and 90 degrees is obtained. Set the dynamic vibration absorber rigidity to be the minimum. The comparators 32 and 33 compare the phase difference information from the phase difference detector 15 with a set value of 270 ° delay or 90 ° delay, and output the result to the stiffness setting controller 31.

Next, the processing operation in this embodiment will be described.
The stiffness setting controller 31 sets a gain term K as a predetermined electrical dynamic vibration absorber stiffness as an initial value. Next, the frequency for the sine wave oscillator 14 is determined within a frequency range centered on the natural frequency of the main system, and the output signal from the sine wave oscillator 14 and the output signal from the displacement sensor 2 are multiplied by a gain term K. The output signal and the signal obtained by differentiating the output signal from the displacement sensor 2 by the differentiator 11 are added to the signal obtained by multiplying the gain term C and supplied to the actuator 1.

  The output from the acceleration sensor 3 is input to the phase difference detector 15, and the phase difference from the output signal from the sine wave oscillator 14 is detected. The detected phase difference is input to each of the comparators 32 and 33, and it is determined whether or not the phase difference is delayed by 270 degrees or 90 degrees. The stiffness setting controller 31 first obtains a sine wave frequency at which the phase difference is delayed by 270 degrees, then obtains a sine wave frequency at which the phase difference is delayed by 90 degrees, and stores the frequency difference at that time. Then, the value of the gain term K is gradually increased or decreased, and the measurement is continued to obtain the value of the gain term K that minimizes the frequency difference.

  FIG. 8 shows the transfer function between the sinusoidal relative excitation force and the main system absolute acceleration by changing the rigidity of the dynamic vibration absorber when the natural frequency of the dynamic vibration absorber is close to the natural frequency of the main system. Is. As can be seen from the figure, there are two peaks near the main system natural frequency, and the following characteristics appear when the stiffness of the dynamic vibration absorber is optimally adjusted. 1) The natural frequency of the main system is located between the two peaks, and the absolute acceleration becomes a minimum value at the natural frequency of the main system. 2) Since the frequency interval between the two peaks is closest, the interval between the frequencies at which the polarity of the absolute acceleration is positively inverted is also minimized.

  Therefore, due to this property, the dynamic vibration absorber rigidity is set so that the absolute acceleration takes a minimum value at the main system natural frequency, or the frequency at which the polarity of the absolute acceleration is reversed in the frequency range sandwiching the main system natural frequency. It can be seen that the dynamic vibration absorber rigidity can be optimized by setting the dynamic vibration absorber rigidity so that the width is minimized.

<Third Embodiment>
In the present embodiment, in the frequency range centered on the main system natural frequency, relative vibration is performed using the dynamic vibration damper attenuation as a parameter to obtain the frequency characteristics of the absolute acceleration, and the main system natural frequency estimated value is the center. The dynamic vibration absorber attenuation constant is set from the curve structure of the frequency characteristics. As shown in FIG. 5, the control unit according to this embodiment includes a differentiator 11, an adder 12, a sine wave oscillator 14, It comprises an attenuation setting controller (natural frequency estimation means, attenuation variable means, frequency characteristic acquisition means, attenuation adjustment means) 41, an amplitude detector 42, and a second-order differentiator 43. In addition, about the element which attached | subjected the code | symbol same as 1st Embodiment, since it has the same function, description is abbreviate | omitted.

  The attenuation setting controller 41 sets an electric dynamic vibration absorber attenuation, and sets a frequency for the sine wave oscillator 14 within a frequency range centered on the natural frequency of the main system obtained in the first embodiment. A dynamic vibration absorber that finely varies and stores the frequency and the second order differential value of the absolute acceleration of the main system, and the frequency characteristics of the absolute acceleration have an inflection point or polarity inversion near the main system natural frequency. Set the attenuation. The amplitude detector 42 detects the amplitude of the output of the acceleration sensor 3, and the second-order differentiator 43 performs second-order differentiation of the amplitude detected by the amplitude detector 22 with respect to the frequency. .

Next, the processing operation in this embodiment will be described.
The attenuation setting controller 41 sets the gain term C as a predetermined electrical dynamic vibration absorber attenuation as an initial value. The gain term K is set to the value obtained in the second embodiment. Next, the frequency for the sine wave oscillator 14 is determined within a frequency range centered on the natural frequency of the main system, and the output signal from the sine wave oscillator 14 and the output signal from the displacement sensor 2 are multiplied by a gain term K. The output signal and the signal obtained by differentiating the output signal from the displacement sensor 2 by the differentiator 11 are added to the signal obtained by multiplying the gain term C and supplied to the actuator 1.

The output from the acceleration sensor 3 is input to the amplitude detector 42, and the amplitude is detected. The detected amplitude information is second-order differentiated by the second-order differentiator 43 and input to the attenuation setting controller 41. The attenuation setting controller 41 becomes an inflection point in the vicinity of the main system natural frequency with a pair of the frequency f given to the sine wave oscillator 14 and d ² A / df ² obtained from the second-order differentiator 43. Or if the polarity is reversed compared to the previous time, the gain term C set previously is set as the electric dynamic vibration absorber attenuation. If not, the gain term C is set to Gradually increase or decrease and continue the above measurement to determine the value of the gain term C that becomes an inflection point near the main system natural frequency. Note that the above criteria were used as criteria for setting the dynamic damper damping because the damping is large when the curve structure is convex upward in the vicinity of the main system natural frequency, and when the convexity is downward. This is because the attenuation is small.

  FIG. 6 shows a modification of the present embodiment. In the present embodiment, the dynamic vibration absorber attenuation constant is set from the curve structure of the frequency characteristics centered on the estimated natural frequency of the main system by limiting the frequency to be observed with respect to the method of FIG. As shown in FIG. 6, the unit includes a differentiator 11, an adder 12, a sine wave oscillator 14, an amplitude detector 42, and an attenuation setting controller 51. In addition, about the element which attached | subjected the code | symbol same as 1st Embodiment, since it has the same function, description is abbreviate | omitted.

  For example, the damping setting controller 51 sequentially sets the upper frequency and the lower frequency for the main system natural frequency and its value, detects the absolute acceleration at that time, and detects the dynamic vibration from the curved structure. Set the instrument damping constant. Specifically, the attenuation setting controller 51 sets the gain term C as a predetermined electrical dynamic vibration absorber attenuation as an initial value. The gain term K is set to the value obtained in the second embodiment. Next, the natural frequency of the main system is set to the sine wave oscillator 14 as a frequency, and the output signal from the sine wave oscillator 14 and the output signal from the displacement sensor 2 are multiplied by the gain term K and the differentiator 11. A signal obtained by differentiating the output signal from the displacement sensor 2 and the signal obtained by multiplying the gain term C is added and supplied to the actuator 1.

  The output from the acceleration sensor 3 is input to the amplitude detector 42, and the amplitude is detected. Next, the attenuation setting controller 51 sets the natural frequency of the main system as a frequency in the sine wave oscillator 14 and detects the output amplitude from the acceleration sensor 3 at that time. Further, the attenuation setting controller 51 sets the natural frequency of the main system as a frequency in the sine wave oscillator 14, detects the output amplitude from the acceleration sensor 3 at that time, and detects the set dynamic damper attenuation. Three pieces of amplitude information are stored in pairs. Then, the above processing is continued while changing the damping of the dynamic vibration absorber, and the dynamic vibration is such that the curved structure becomes the curved structure of the boundary from the convex downward to the convex with the main system natural frequency as the center. Set instrument attenuation.

  As shown in FIG. 9, paying attention to the transfer function of the sinusoidal relative excitation force and the main system absolute acceleration when the rigidity of the dynamic vibration absorber is optimally adjusted and when the attenuation of the dynamic vibration absorber is changed, There are features. 1) Two peaks appear when the dynamic vibration absorber attenuation is smaller than the optimum adjustment value. That is, the curve structure is convex downward with the main system natural frequency as the center. 2) One peak appears when the dynamic vibration absorber attenuation is larger than the optimum adjustment value. That is, the curved structure is convex upward with the main system natural frequency as the center.

  Therefore, using this characteristic, in the estimated value of the main system natural frequency, the dynamic vibration absorber is used at the boundary where the acceleration curve changes from convex downward to convex upward (so-called inflection point where the second-order differential value becomes zero). If attenuation is set, an approximate value of the optimum adjustment value can be given. In FIG. 9, the thick line indicates the characteristic at the optimum attenuation, the dotted line indicates the characteristic when the attenuation is half of the optimum value, and the broken line indicates the characteristic when the attenuation is twice the optimum value. Yes.

  However, if the estimated value of the main system natural frequency is different from the actual value, or if the main system natural frequency does not match the natural vibration absorber natural frequency, the center of the convex structure (inflection point) is the main It may deviate from the estimated natural frequency of the system. However, as in this embodiment, the frequency characteristics of the absolute acceleration are obtained by finely changing the frequency in the vicinity of the main system natural frequency estimated value, the frequency structure of the absolute acceleration is checked finely, and the curve structure is convex downward or convex upward. In addition, by using a method for determining whether or not to switch, even if there is a slight shift in the center of the convex structure, the determination is not affected.

  Also, by limiting the frequency to be observed, the absolute acceleration at the frequency to be observed is detected for each damping constant, and whether it is convex downward, convex upward, or switching around the estimated natural frequency of the main system. By using the determination method, even if there is a slight shift in the center of the convex structure, if the shift is small, a substantially true curved structure can be detected.

  As mentioned above, although embodiment of this invention was described in detail, this invention is not limited to embodiment mentioned above, A various deformation | transformation and application are possible within the range which does not deviate from the summary of this invention. For example, in the present invention, the example provided with the displacement sensor that detects the relative displacement between the dynamic vibration absorber mass and the main system has been described. Alternatively, a sensor that detects the relative velocity or the relative acceleration may be used. Good. In this case, arithmetic processing and waveform processing are performed on the value obtained from the sensor, and the relative velocity or relative acceleration is converted into relative displacement.

  In the present invention, an example in which an acceleration sensor for detecting the absolute acceleration of the main system is provided has been described. Alternatively, a sensor for detecting absolute displacement or absolute velocity may be used. In this case, arithmetic processing or waveform processing is performed on the value obtained from the sensor to convert absolute displacement or absolute velocity into absolute acceleration.

  In the first and second embodiments, the main system has been described as a vibration system with one degree of freedom, but the main system may be a multi-degree-of-freedom system. In this case, the dynamic vibration absorber uses one of the natural frequencies of the main system as a vibration suppression target. If the natural frequency to be controlled is the lowest, there is no need to change the control algorithm, but if there is a natural frequency lower than the target natural frequency, the control algorithm is changed. There is a need to. That is, in the first embodiment, the absolute acceleration is adjusted so as to be 90 + 180 * N degrees behind the sinusoidal excitation force (or 270 + 180 * N degrees behind). In the second embodiment, the phase difference between the relative excitation force and the absolute acceleration at the main system natural frequency when the dynamic vibration absorber natural frequency is set close to the main system natural frequency is about −180−. 180 * N degrees, and the polarity reversal of absolute acceleration occurs at -270-180 * N degrees and -90-180 * N degrees.

  In the second embodiment, the setting of the dynamic vibration absorber rigidity has been described. However, with respect to the dynamic vibration absorber before being attached to the main system, the proportional gain of the force proportional to the relative displacement and the dynamic vibration absorber natural frequency Then, a correspondence table of proportional gains of forces proportional to the natural vibration frequency vs. relative displacement is created. At that time, the dynamic vibration absorber is floated with a sponge or the like for measurement. At the time of setting the stiffness, a value for matching the main system natural frequency and the dynamic vibration absorber natural frequency estimated in the first embodiment is directly obtained from the created table, or is obtained by interpolation from the table value. You may do it.

  In the third embodiment, the setting of damping of the dynamic vibration absorber has been described. However, the frequency to be observed, such as the main system natural frequency estimated value, the upper frequency points, and the lower frequency points, is set. When observing the frequency characteristics of the main system absolute acceleration in a limited manner, the polarity of the absolute acceleration is reversed at a frequency higher than the natural frequency of the main system observed in the second embodiment for obtaining the dynamic vibration absorber rigidity for the upper frequency. The lower frequency may be a frequency near the frequency near the frequency where the polarity of the absolute acceleration is inverted at a frequency lower than the main system natural frequency. Again, at these frequencies, the respective accelerations have peak values, so that a clear change in the curve structure can be obtained.

1 is a basic configuration diagram of the present invention. It is a block diagram of the control part in 1st Embodiment. It is a block diagram of the control part in 2nd Embodiment. It is a block diagram of the control part of the modification in 2nd Embodiment. It is a block diagram of the control part in 3rd Embodiment. It is a block diagram of the control part of the modification in 3rd Embodiment. It is the figure which showed the transfer function of the relative excitation force and main system absolute acceleration in 1st Embodiment. It is the figure which showed the transfer function of the relative excitation force and main system absolute acceleration in 2nd Embodiment. It is the figure which showed the transfer function of the relative excitation force and main system absolute acceleration in 3rd Embodiment. It is a figure which shows the conventional basic composition.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Actuator, 2 ... Displacement sensor, 3 ... Acceleration sensor, 4 ... Control part, 5 ... Dynamic vibration absorber mass, 6 ... Main system mass, 11 ... Differentiator , 12 ... adder (thrust output means), 13 ... natural frequency estimation controller (frequency variable means, natural frequency estimation means), 14 ... sine wave oscillator (sine wave generation means), 15 ... Phase difference detector, 16 ... Comparator, 21 ... Rigidity setting controller (natural frequency variable means, frequency characteristic acquisition means, tuning means), 22 ... Amplitude detector, 23 ... Differentiator, 31 ... rigidity setting controller (phase difference acquisition means, storage means, tuning means), 32, 33 ... comparator, 41, 51 ... damping setting controller (natural frequency estimation means) , Attenuation variable means, frequency characteristic acquisition means, attenuation adjustment means), 42... Amplitude detector, 43. 2 floor differentiator,

Claims (8)

An actuator that generates thrust between the main system part and the dynamic vibration absorber, a displacement sensor that detects a relative displacement between the main system part and the dynamic vibration absorber, an acceleration sensor that detects the absolute acceleration of the main system part, A vibration absorber including a control unit that controls thrust generated by the actuator,
A sine wave generating means for generating a sine wave thrust command, a displacement corresponding thrust command generating means for generating a thrust command obtained by multiplying the output of the displacement sensor by a predetermined proportional constant, and an output of the displacement sensor A speed-corresponding thrust command generating means for generating a thrust command proportional to the differential value, and a thrust command generated from the sine wave generating means, a displacement-corresponding thrust command generating means and a speed-corresponding thrust command generating means A thrust command output means for outputting; a frequency variable means for changing the frequency of the sine wave; and detecting a phase difference between the phase of the sine wave and the signal output from the acceleration sensor, and the phase difference is set to a predetermined value. A vibration absorbing device comprising natural frequency estimating means for estimating the natural frequency of the main system from the frequency of the sine wave when the value is reached.   The dynamic vibration absorber rigidity in which the predetermined proportionality constant is such that the natural frequency of the dynamic vibration absorber is at least twice the upper limit frequency of the range of the natural frequency of the main system part or 1/2 or less of the lower limit frequency. The vibration absorbing device according to claim 1, wherein the value is obtained.   The natural frequency estimating means sets the frequency of the sine wave when the phase of the signal output from the acceleration sensor is delayed by 90 degrees or 270 degrees with respect to the phase of the sine wave. The vibration absorbing device according to claim 2, wherein the vibration absorbing device is estimated as a natural frequency of the main system portion.   The control unit changes the predetermined proportionality constant to vary the natural frequency of the dynamic vibration absorber, and the natural frequency variable means for varying the natural frequency of the dynamic vibration absorber, and the frequency variable means to determine the natural frequency estimation means. In the frequency characteristic obtaining means for obtaining the frequency characteristic of the signal obtained from the acceleration sensor and the frequency characteristic obtained by the frequency characteristic obtaining means, the frequency characteristic obtained by 4. The tuning device according to claim 1, further comprising tuning means for determining the predetermined proportionality constant so that a frequency corresponding to the value becomes a natural frequency of the main system portion. Vibration absorber.   The control unit changes the predetermined proportionality constant to vary the natural frequency of the dynamic vibration absorber, and the natural frequency variable means for varying the natural frequency of the dynamic vibration absorber, and the frequency variable means to determine the natural frequency estimation means. Phase difference obtaining means for obtaining a phase difference between the signal obtained from the acceleration sensor and the sine wave, the phase difference of the signal obtained from the acceleration sensor Means for storing the frequency of the sine wave which is delayed by 270 degrees and 90 degrees with respect to the phase of the sine wave, and the frequency of the sine wave and the 90 degree delay when the stored 270 degree delay 4. The tuning device according to claim 1, further comprising tuning means for determining the predetermined proportionality constant so that a frequency difference with the frequency of the sine wave at the time is minimized. Mounting vibration absorbing device. An actuator that generates thrust between the main system part and the dynamic vibration absorber, a displacement sensor that detects a relative displacement between the main system part and the dynamic vibration absorber, an acceleration sensor that detects the absolute acceleration of the main system part, A vibration absorber including a control unit that controls thrust generated by the actuator,
The control unit has a sine wave generating means for generating a sine wave thrust command, a displacement corresponding thrust command generating means for generating a thrust command proportional to the output of the displacement sensor, and a differential value of the output of the displacement sensor is predetermined. A speed-corresponding thrust command generating means for generating a thrust command multiplied by a proportional constant, and a thrust command generated from the sine wave generating means, a displacement-corresponding thrust command generating means and a speed-corresponding thrust command generating means A thrust command output means for outputting; a frequency variable means for changing the frequency of the sine wave; and detecting a phase difference between the phase of the sine wave and the signal output from the acceleration sensor, and the phase difference is set to a predetermined value. The natural frequency estimating means for estimating the natural frequency of the main system from the frequency of the sine wave when the value is reached, and the predetermined proportionality constant are changed to allow the dynamic absorber to be attenuated. The frequency of the signal obtained from the acceleration sensor by changing the frequency of the sine wave in the vicinity of the estimated natural frequency of the main part obtained by the natural frequency estimating means by the attenuation variable means and the frequency variable means. Frequency characteristic acquisition means for acquiring characteristics, attenuation adjustment means for determining the predetermined proportionality constant so that the curve structure of the frequency characteristics has a predetermined uneven shape,
A vibration absorbing device comprising:   The attenuation adjusting means sets the predetermined proportionality constant so that the curve structure of the frequency characteristic becomes a curve structure of a boundary from a convex downward to a convex upward with the vicinity of the estimated natural frequency of the main system part as a vertex. The vibration absorber according to claim 6, wherein the vibration absorber is determined. The said attenuation adjustment means determines the said predetermined proportionality constant so that the curve structure of a frequency characteristic may become an inflexion point in the vicinity of the presumed natural frequency of the said main part. Vibration absorber.

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