JPH07243858A - Vibration controller - Google Patents

Abstract

PURPOSE:To provide a vibration controller in which the frequency of the self-excited vibration of a vibrator can be set to a frequency which nearly matches the mechanical serial resonance frequency. CONSTITUTION:A vibration controller is provided with a vibrator 4 with one piezoelectric element 5 on the side surface of a vibration body with a resonance point, a drive device 6 with a signal output terminal 9 for outputting the drive signal of the vibrator 4, and a feedback amplifier 10 with an input terminal 12 for feedback and an input terminal 11 for signal. Then, the input terminal 11 for the feedback amplifier 10 is connected to the signal output terminal 9 of the drive device 6 and the input terminal 12 for feedback is connected to one electrode of the piezoelectric element 5 and the other electrode of the piezoelectric element 5 is connected to the ground.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vibration control device used in, for example, a piezoelectric vibration gyro.

[0002]

2. Description of the Related Art As a conventional vibrating gyroscope, for example,
There is one as shown in FIG. In this vibrating gyro, the piezoelectric elements 2 and 3 forming the vibrator 4 are connected to the output side of the drive unit 6 via impedance elements Z ₁ and Z ₂ , respectively, and the output side of the drive unit 6 is further Is connected to the capacitive element C via the impedance element Z ₃ of FIG. 3 and the drive signal from the drive device 6 is simultaneously applied to the piezoelectric elements 2 and 3 and the capacitive element C.

The outputs at the connection points of the impedance elements Z ₁ and Z ₂ and the piezoelectric elements 2 and 3 are combined, and the combined output and the output at the connection point of the impedance element Z ₃ and the capacitive element C are combined. By supplying the differential output to the differential amplifier 7 and feeding back the differential output to the driving device 6, the vibrator 4 is caused to self-oscillate, and further, these impedance elements Z ₁ and Z ₂ and the piezoelectric elements 2 and 3 are connected. The outputs at the respective connection points are supplied to the other differential amplifier 8 so that the angular velocity detection signal is obtained based on the output of the differential amplifier 8.

Here, for example, as shown in FIG. 19, the vibrator 4 has a quadrangular cross section, and the piezoelectric element 2 is provided on one side surface 1a of the vibrating body 1 having a resonance point and the side surface 1a thereof. One in which the piezoelectric elements 3 are respectively formed on the other adjacent side surfaces 1b, one in which the piezoelectric elements 2 and 3 are formed in the width direction on the same side surface of the vibrating body 1 as shown in FIG.
2, the piezoelectric elements 2 and 3 are formed on the opposite side surfaces of the vibrating body 1 so as to be displaced in the width direction, or
As shown in FIG. 2, piezoelectric elements 2a and 2b are formed and connected in parallel so that they substantially act as one piezoelectric element 2 on opposite side surfaces of the vibrating body 1, and
Piezoelectric elements 3a and 3b are formed and connected in parallel so that they substantially act as one piezoelectric element 3 on the other opposing side surfaces.

Further, as the other vibrator 4, as shown in FIG. 23, a vibrator having a triangular cross section and piezoelectric elements 2 and 3 formed on two side surfaces of a vibrating body 1 having a resonance point. As shown in FIG. 24, the cross-sectional shape is circular,
A vibrating body having a resonance point having piezoelectric elements 2 and 3 formed on the circumferential side surface thereof, or a vibrating body having various transverse cross-sectional shapes having substantially two piezoelectric elements formed on its side surface is used.

Incidentally, here, as shown in FIG. 25, a vibrator 4 formed by forming one piezoelectric element 5 on a vibrating body 1,
As shown in FIG. 26, and as illustrated in FIGS. 19 to 24, substantially two piezoelectric elements 2 and 3 are provided on the vibrating body 1.
The vibrator 4 formed by forming is shown as shown in FIG.

[0007]

However, as shown in FIG.
In the conventional vibrating gyroscope shown in FIG. ₁ , the drive signal from the drive device 6 is applied to the piezoelectric elements 2 and 3 via the impedance elements Z ₁ and Z _2, and therefore the vibrator 4
When the impedance of the piezoelectric elements 2 and 3 decreases near the mechanical series resonance frequency f _S of
The signal level applied to 3 decreases, and the frequency at which the output of the differential amplifier 7 becomes maximum does not match the mechanical series resonance frequency f _{S of} the vibrator 4. This phenomenon will be described below with reference to FIGS. 28 and 29.

FIGS. 28A and 28B show an example of measuring the frequency characteristic and the phase characteristic of the admittance | Y | of the vibrator 4 having the configuration shown in FIG. 19, and FIGS.
3 shows transfer characteristics and phase characteristics of the differential amplifier 7. In the vibration gyro shown in FIG. 18, the piezoelectric elements 2, 3
Are connected in series to the impedance elements Z ₁ and Z ₂ , respectively, so that the signal levels applied to these piezoelectric elements 2 and 3 are in the vicinity of the mechanical series resonance frequency f _S of large | Y | from FIG. 28A. It is understood that it decreases and increases in the vicinity of the mechanical parallel resonance frequency f _{a where} | Y | is small. For this reason, the output of the differential amplifier 7 is affected by the mechanical parallel resonance frequency f _a having a high applied signal level, and the frequency showing the maximum value is as shown in FIG. 29A. It shifts toward f _a .

Further, in the vibrator 4, for one piezoelectric element, as shown in the equivalent circuit of FIG. 30, the damping capacitance Cd is connected in parallel to the series resonance circuit of the coil L ₁ , the capacitor C ₁ and the resistor R _1. is represented by a parallel resonance circuit, and the impedance element Z _1, Z _2, for example, resistance, capacitor or the like is used, for example, the impedance element Z _1,
When a resistor is used as Z ₂ , the applied signal also causes a phase change determined by the value of the damping capacitance Cd with respect to the resistance value of the impedance elements Z ₁ and Z ₂ . Therefore, both the level and the phase of the applied signal change intricately as the impedance of the oscillator 4 changes, and the frequency at which the output of the differential amplifier 7 becomes maximum is closer to the mechanical parallel resonance frequency f _a. turn into.

Furthermore, since the equivalent constant of the oscillator 4, that is, the damping capacitance Cd, the coil L ₁ , the capacitor C ₁ and the resistance R ₁ have different temperature dependences, the differential amplifier 7 is affected by a change in ambient temperature. The frequency at which the output of becomes maximum changes. Here, since the self-excited vibration occurs at the frequency where the output of the differential amplifier 7 becomes maximum, the set frequency of the self-excited vibration easily changes due to the change of the ambient temperature.

The mechanical quality factor Q _m of the oscillator 4 is
Since the value on the piezoelectric element 2 side and the value on the piezoelectric element 3 side do not exactly match, the impedance elements Z ₁ and Z ₂ and the piezoelectric element 2 are changed with the change in the set frequency of the self-excited vibration. A difference occurs in the output at the connection point of No. 3, and the null voltage is likely to be generated and changed.

Further, the vibrator 4 has its piezoelectric elements 2, 3
Since the impedance elements Z ₁ and Z ₂ are connected to each other and have a high impedance as a whole, it is said that the connection points of the piezoelectric elements 2 and 3 and the impedance elements Z ₁ and Z ₂ are easily affected by electrical noise. There are also problems.

A first object of the present invention is to provide a vibration control device appropriately configured so that the frequency of self-excited vibration of a vibrator can be set to a frequency substantially matching the mechanical series resonance frequency f _S thereof. It is what A second object of the present invention is to provide a vibration control device appropriately configured so that the frequency of self-excited vibration of a vibrator can be set to a frequency that exactly matches its mechanical series resonance frequency f _S. It is a thing. A third object of the present invention is to set the frequency of the self-excited vibration of the vibrator to a frequency that substantially matches the mechanical series resonance frequency f _S , and to effectively reduce the occurrence and fluctuation of null voltage. Therefore, the present invention is intended to provide a vibration control device properly configured. A fourth object of the present invention is to set the frequency of the self-excited vibration of the vibrator to a frequency that exactly matches the mechanical series resonance frequency f _S thereof, and effectively reduce the occurrence and fluctuation of null voltage. It is an object of the present invention to provide a vibration control device that is appropriately configured so as to be capable.

[0014]

In order to achieve the above-mentioned first object, the first invention provides: A vibrator having one piezoelectric element on a side surface of a vibrating body having a resonance point, a driving device having a signal output terminal for outputting a driving signal of the vibrator, and a feedback amplifier having a feedback input terminal and a signal input terminal And the signal input terminal of the feedback amplifier to the signal output terminal of the driving device,
The feedback input terminals are respectively coupled to one electrode of the piezoelectric element, and the other electrode of the piezoelectric element is coupled to the ground.

In order to achieve the above second object, the second invention provides: A vibrator having one piezoelectric element on a side surface of a vibrating body having a resonance point, a signal output terminal for outputting a drive signal of the vibrator, and a compensation signal output terminal for outputting a compensation signal of the braking capacity of the vibrator. A driving device; and a feedback amplifier having a feedback input terminal and a signal input terminal, the signal input terminal of the feedback amplifier being a signal output terminal of the driving device, and the feedback input terminal being one of the piezoelectric elements. And the other electrode of the piezoelectric element is connected to the compensation signal output terminal of the driving device.

According to the third invention, 3. A vibrator having one piezoelectric element on a side surface of a vibrating body having a resonance point, a signal output terminal for outputting a drive signal of the vibrator, and a compensation signal output terminal for outputting a compensation signal of the braking capacity of the vibrator. A driving device; and a feedback amplifier having a feedback input terminal and a signal input terminal, the signal input terminal of the feedback amplifier being a signal output terminal of the driving device, and the feedback input terminal being one of the piezoelectric elements. Of the piezoelectric element, the other electrode of the piezoelectric element is coupled to the ground, and the compensation signal output terminal of the driving device is coupled to the output terminal of the feedback amplifier.

In order to achieve the above-mentioned third object, the fourth invention provides: A vibrator having substantially a pair of piezoelectric elements on a side surface of a vibrating body having a resonance point, a driving device having a signal output terminal for outputting a driving signal of the vibrator, and a feedback input terminal and a signal input terminal, respectively. And two feedback amplifiers, and the respective signal input terminals of these two feedback amplifiers are coupled to the signal output terminal of the driving device,
A feedback input terminal of one feedback amplifier is coupled to one electrode of the one piezoelectric element, and a feedback input terminal of the other feedback amplifier is coupled to one electrode of the other piezoelectric element,
The other electrode of each of these piezoelectric elements is coupled to the ground.

In order to achieve the above-mentioned fourth object, the fifth invention provides: A vibrator having substantially a pair of piezoelectric elements on the side surface of a vibrating body having a resonance point, a signal output terminal for outputting a drive signal for the vibrator, and a compensation signal output terminal for outputting a compensation signal for the braking capacitance of the vibrator are provided. A driving device having the same, and two feedback amplifiers each having a feedback input terminal and a signal input terminal, and the respective signal input terminals of these two feedback amplifiers are coupled to the signal output terminal of the driving device. , The feedback input terminal of one feedback amplifier is coupled to one electrode of the one piezoelectric element, and the feedback input terminal of the other feedback amplifier is coupled to one electrode of the other piezoelectric element. Each of the other electrodes is coupled to a compensation signal output terminal of the driving device.

According to the sixth aspect of the invention, A vibrator having substantially a pair of piezoelectric elements on the side surface of a vibrating body having a resonance point, a signal output terminal for outputting a drive signal for the vibrator, and a compensation signal output terminal for outputting a compensation signal for the braking capacitance of the vibrator are provided. A driving device having the same, and two feedback amplifiers each having a feedback input terminal and a signal input terminal, and the respective signal input terminals of these two feedback amplifiers are coupled to the signal output terminal of the driving device. , The feedback input terminal of one feedback amplifier is coupled to one electrode of the one piezoelectric element, and the feedback input terminal of the other feedback amplifier is coupled to one electrode of the other piezoelectric element. Each of the other electrodes is coupled to the ground, and the compensation signal output terminal of the driving device is coupled to each output terminal of the two feedback amplifiers. .

In a preferred embodiment of the present invention,
It is characterized in that the vibration control device is configured as follows. 7. In the vibration control device according to the above-mentioned 1, the output signal of the feedback amplifier is fed back to the drive device so that the vibrator is stably self-oscillated at substantially the mechanical series resonance frequency, or 2. The vibration control device according to 2, wherein the output signal of the feedback amplifier is fed back to the drive device so that the vibrator is stably self-excited at a frequency exactly matching its mechanical series resonance frequency. . 8. 4. In the vibration control device according to the above 4, the output signals of the two feedback amplifiers are combined and fed back to the drive device to stabilize and vibrate the oscillator substantially at its mechanical series resonance frequency. Alternatively, in the vibration control device described in the above 5, the output signals of the two feedback amplifiers are combined and fed back to the drive device to bring the vibrator to its mechanical series resonance frequency. Make sure that the self-excited vibration is stable and at exactly the same frequency. 9. In the vibration control device according to the above 3, the composite output of the compensation signal from the compensation signal output terminal of the drive device and the output signal of the feedback amplifier is fed back to the drive device, and the vibrator is mechanically connected in series. Stable self-excited oscillation at a frequency that exactly matches the resonance frequency. 10. In the vibration control device according to the above 6, the composite output of the compensation signal from the compensation signal output terminal of the drive device and the output signals of the two feedback amplifiers is fed back to the drive device to drive the oscillator. Stable self-excited oscillation is performed at a frequency that exactly matches the mechanical series resonance frequency. 11. In the vibration control device according to the above 2, 3, 5, 6, 9 or 10, the driving device is configured to correspond to the value of the braking capacity of the vibrator, and the amplitude and phase of the compensation signal from the compensation signal output terminal. Is changed so that the vibrator stably oscillates at a frequency that exactly matches its mechanical series resonance frequency. 12. In the vibration control device described in 4, 5, 6, 8, 10 or 11, a differential amplifier for detecting a difference between outputs of the two feedback amplifiers is provided so that an angular velocity acting on the vibrator can be detected. To 13. In the vibration control device described in 2, 3, 5, 6, 9, 10 or 11, the drive device includes a capacitor having a temperature dependency corresponding to the temperature dependency of the braking capacity of the vibrator, The capacitor is configured to change the amplitude and phase of the compensation signal output from the compensation signal output terminal in accordance with the temperature dependence of the braking capacitance of the vibrator, without being affected by changes in ambient temperature, The oscillator is made to stably oscillate at a frequency exactly matching its mechanical series resonance frequency. 14. 2, 3, 5, 6, 9, 10, 11 or 13 above
In the vibration control device described above, the capacitor is made of the same composition as that of the piezoelectric element, and the temperature dependence of the damping capacity of the vibrator and the temperature dependence of the compensation signal thereof are matched to each other. The vibrator is made to vibrate stably at a frequency that exactly matches its mechanical series resonance frequency, without being affected by changes in temperature.

[0021]

In the first aspect of the invention, when the signal output terminal of the driving device is coupled to the signal input terminal of the feedback amplifier and one electrode of the piezoelectric element is coupled to the feedback input terminal of the feedback amplifier, the feedback of the feedback amplifier is returned. The voltage gain changes according to the impedance of the piezoelectric element, and becomes maximum at a frequency substantially matching the mechanical series resonance frequency f _S of the vibrator. Therefore, it is possible to set the frequency of self-excited vibration that substantially matches the mechanical series resonance frequency f _S of the vibrator.

Further, as in the second aspect of the invention, by inputting the compensation signal of the damping capacitance of the vibrator output from the compensation signal output terminal of the driving device to the other electrode side of the piezoelectric element, or the above-mentioned second aspect. As in the third aspect of the invention, by combining the compensation signal with the output signal of the feedback amplifier, a slight deviation from the mechanical series resonance frequency f _S of the oscillator due to the damping capacitance is compensated, and more accurate self-excited oscillation is obtained. The frequency can be set.

Therefore, in the fourth invention for controlling the vibration of the vibrator having substantially a pair of piezoelectric elements, the frequency of the self-excited vibration of the vibrator is set to a frequency substantially matching the mechanical series resonance frequency f _S. In addition, the respective outputs of the feedback amplifiers corresponding to the respective piezoelectric elements are stabilized, so that the generation and fluctuation of the null voltage can be effectively reduced. Further, in the fifth and sixth inventions, the vibrator is provided. The frequency of the self-excited vibration can be set to a frequency that exactly matches the mechanical series resonance frequency f _S , and similarly, the occurrence and fluctuation of the null voltage can be effectively reduced.

[0024]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows a first embodiment of the present invention. In FIG. 1, the same parts as those described in the prior art are designated by the same reference numerals. This example
For example, the vibration of the vibrator 4 shown in FIG. 25, that is, the vibrator 4 configured by forming the piezoelectric element 5 on the side surface of the vibrating body 1 having the resonance point is controlled. Is connected to the feedback input terminal 12 side of the feedback amplifier 10, and the other electrode side is grounded. The signal input terminal 11 side of the feedback amplifier 10 is connected to the signal output terminal 9 of the driving device 6.
And the drive signal is supplied to the input terminal 14 of the drive device 6. A feedback resistor R _f is connected between the output terminal side of the feedback amplifier 10 and the feedback input terminal 12 side.

In the above structure, the output V _F of the feedback amplifier 10 is different from the signal output V _DR of the driving device 6 at the mechanical series resonance frequency f _S of the vibrator 4.

[Equation 1] Becomes Here, the equivalent constant of the practical oscillator 4 is, for example, a braking capacitance Cd of about 500 pF and a resistance R _{1 of about} 5
Braking capacitance Cd for feedback voltage gain | A |
Can be almost ignored, so

[Equation 2] Becomes Therefore, the maximum value of the feedback voltage gain | A | can be obtained at a frequency substantially matching the mechanical series resonance frequency f _S.

FIG. 2 shows a second embodiment of the present invention. This embodiment controls the vibration of the vibrator 4 similar to that described with reference to FIG. 1, and the driving device 6 outputs a compensation signal output terminal 1 for outputting a compensation signal for the braking capacity of the vibrator 4.
3 is different from that of the first embodiment in that the compensation signal output terminal 13 side is connected to the other electrode side of the piezoelectric element 5. Here, from the compensation signal output terminal 13, in the above formula (1), (1 + j2πf _S Cd
A compensation signal that eliminates the R _f ) term is output.

Therefore, according to this embodiment, the feedback voltage gain | A | of the feedback amplifier 10 is at the mechanical series resonance frequency f _S of the oscillator 4,

[Equation 3] Therefore, the maximum value is obtained at the frequency that exactly matches the mechanical series resonance frequency f _S.

FIG. 3 shows the compensation signal output terminal 13 shown in FIG.
2 shows an example of the configuration of a driving device 6 having a. The driving device 6 has amplifiers 15 and 16, a feedback amplifier 17, and a capacitor Cd ₀ . The input terminal 14 of the driving device 6 is connected to the input side of the amplifier 15 and the amplifier 15
Is connected to the input side of the amplifier 16 and is also connected to the signal input terminal 18 of the feedback amplifier 17. Amplifier 1
The output side of 6 is connected to the signal output terminal 9 of the drive device 6. The feedback input terminal 19 of the feedback amplifier 17 is grounded via the capacitor Cd ₀ , and the feedback resistor Rf _{0 is provided} between the feedback input terminal 19 and the output side of the feedback amplifier 17, that is, the compensation signal output terminal 13. Connect.

In the driving device 6 shown in FIG. 3, the output voltage V _C of the feedback amplifier 17 is at the mechanical series resonance frequency f _S of the oscillator 4 with respect to the signal output V _DR .

[Equation 4] Becomes Therefore, by appropriately setting the capacitor Cd ₀ and the feedback resistor Rf ₀ , that is, Cd ₀
By setting Rf ₀ = CdR _f , the above expression (3) can be realized. Here, the capacitor Cd ₀ preferably has a temperature dependence corresponding to the temperature dependence of the braking capacitance Cd of the vibrator 4, and particularly preferably has the same composition as the piezoelectric elements 2 and 3. The temperature dependence of the damping capacitance Cd of the vibrator 4 is made to match with that of the vibrator 4 accurately by matching the mechanical series resonance frequency f _S of the vibrator without being affected by the change in ambient temperature. It is preferable in that it vibrates stably at a frequency.

FIG. 4 shows a third embodiment of the present invention. In this embodiment, substantially two piezoelectric elements 2 and 3 are formed on the side surface of a vibrator 4 as shown in FIGS. 19 to 24, that is, a vibrator 1 having various cross-sectional shapes having resonance points. The vibration of the vibrator 4 is controlled. In FIG. 4, the signal output terminal 9 side of the driving device 6 is connected to the signal input terminals 11L and 11R sides of the feedback amplifiers 10L and 10R, respectively. The feedback input terminals 12L and 12R of the feedback amplifiers 10L and 10R are connected to one electrodes of the piezoelectric elements 2 and 3, respectively, and the other electrodes of the piezoelectric elements 2 and 3 are grounded. In addition, feedback amplifiers 10L and 10R
Of the feedback amplifiers 10L and 10R and the corresponding signal input terminals 11L and 11R side,
The feedback resistors Rf _L and Rf _R are connected respectively.

With this configuration, as described with reference to FIG. 1, the feedback voltage gains | A of the feedback amplifiers 10L and 10R are substantially equal to the mechanical series resonance frequency f _S of the oscillator 4, respectively. The maximum value of _L |, | A _R | can be obtained. In this configuration, using the same oscillator 4 as that used in the measurement of FIGS. 28 and 29, the results of measuring the transfer characteristics and the phase characteristics of the combined outputs of the feedback amplifiers 10L and 10R are shown in FIGS. Shown in B.

FIG. 6 shows a fourth embodiment of the present invention. This embodiment controls the vibration of the oscillator 4 similar to that described with reference to FIG. 4, and similarly to the one described with reference to FIG. 2, the drive device 6 having the compensation signal output terminal 13 is used. Compensation signal output terminal 13 side is piezoelectric element 2,
3 is connected to the other electrode side.

With this configuration, the mechanical series resonance frequency f _S of the oscillator 4 is similar to that described with reference to FIG.
At the feedback amplifier 10 corresponding to each piezoelectric element 2 and 3
From the above equation (1) representing the feedback voltage gain of L and 10R, (1
Since each term of + j2πf _S CdR _f ) can be eliminated, the feedback amplifiers 10L and 10L and 10L are provided at a frequency exactly matching the mechanical series resonance frequency f _{S of} the oscillator 4.
It is possible to obtain the maximum value of the respective feedback voltage gains | _AL | and | _AR | of _R.

FIG. 7 shows a fifth embodiment of the present invention. In this embodiment, in the configuration shown in FIG. 1, the drive device 6 having the compensation signal output terminal 13 shown in FIG. 3 is used, and the compensation signal output and the output of the feedback amplifier 10 are combined. Is.

In this way, if the compensation signal output of the driving device 6 and the output of the feedback amplifier 10 are combined, the mechanical series resonance frequency f _S of the oscillator 4 exactly matches, as described with reference to FIG. It is possible to obtain the maximum value of the feedback voltage gain | A | of the feedback amplifier 10 at the specified frequency.

FIG. 8 shows a sixth embodiment of the present invention. In this embodiment, in the configuration shown in FIG. 4, the driving device 6 having the compensation signal output terminal 13 shown in FIG. 3 is used, and the compensation signal output and the feedback amplifier 10L,
This is to combine the respective outputs of 10R.

With this configuration, as described with reference to FIG. 6, the outputs of the feedback amplifiers 10L and 10R are driven at the frequencies that exactly match the mechanical series resonance frequency f _S of the oscillator 4. The maximum value of the combined output with the compensation signal output of the device 6 can be obtained. In this configuration, the same oscillator as that used in the measurement of FIGS. 28 and 29 is used as the oscillator 4, and the combined output of the respective outputs of the feedback amplifiers 10L and 10R and the compensation signal output of the driving device 6 is transmitted. The measurement results of the characteristics and the phase characteristics are shown in FIG. 9A.
And B.

FIGS. 10, 11 and 12 show the seventh, eighth and ninth embodiments of the present invention, respectively.
In the configurations shown in FIGS. 1, 2 and 7, respectively, the output side of the feedback amplifier 10 is connected to the input terminal 14 of the driving device 6 so that the vibrator 4 is self-excited. With this configuration, the frequency at which the output of the feedback amplifier 10 described with reference to FIGS. 1, 2 and 7 is maximized, that is, in FIG. 10, the frequency that is substantially equal to the mechanical series resonance frequency f _S of the oscillator 4 is obtained. Then, in FIGS. 11 and 12, stable self-excited vibration is possible at a frequency that exactly matches the mechanical series resonance frequency f _S of the vibrator 4.

FIGS. 13, 14 and 15 show the tenth, eleventh and twelfth embodiments of the present invention, respectively. In the configurations shown in FIGS. 4, 6 and 8, the feedback amplifier 10L, Drive device 6 with combined output of 10R
Is supplied to the input terminal 14 to cause the vibrator 4 to self-excitately vibrate. With this configuration, as shown in FIG.
The feedback amplifier 10L described in FIGS. 6 and 8 respectively,
The frequency at which the combined output of 10R is maximum, that is, FIG.
In Fig. 14 and Fig. 15, a stable self-excited vibration is obtained at a frequency that substantially matches the mechanical series resonance frequency f _S of the vibrator 4, and at a frequency that exactly matches the mechanical series resonance frequency f _S of the vibrator 4 in Figs. Is possible.

16 and 17 show a thirteenth embodiment of the present invention.
And the fourteenth embodiment respectively. In the configuration shown in FIGS. 15 and 14, respectively, the feedback amplifier 10
A differential amplifier 20 for obtaining differential outputs of L and 10R is added. In these examples, the oscillator 4 can be stably oscillated at a frequency exactly matching the mechanical series resonance frequency f _S , and the angular velocity of the oscillator 4 is increased under the self-excited oscillation state. When applied, the Coriolis force generated thereby can be detected as a voltage from the differential amplifier 20.

In FIGS. 16 and 17, the mechanical quality factor Q _m of the vibrator 4 is exactly the same as the observed value on the piezoelectric element 2 side and the observed value on the piezoelectric element 3 side. Even if it is not, the frequency of the self-excited vibration exactly matches the mechanical series resonance frequency f _S of the vibrator 4, so that an output that does not accompany the Coriolis force of the differential amplifier 20, that is, a null voltage is generated. The fluctuation can be suppressed to a small level.

Although the operational amplifier is used as the feedback amplifier in each of the above-described embodiments, other feedback amplifiers may be used. In addition, FIG. 4, FIG. 6, FIG.
16, the differential amplifier for obtaining the differential output of the feedback amplifiers 10L and 10R may be provided to detect the angular velocity acting on the vibrator 4, as in FIGS. Also in these cases, the generation and fluctuation of the null voltage can be suppressed to be small, as in FIGS. 16 and 17. Further, in FIGS. 4 and 6, it is not always necessary to combine the outputs of the feedback amplifiers 10L and 10R.

[0043]

As described above, according to the first aspect of the present invention, the feedback voltage gain of the feedback amplifier can be maximized at a frequency substantially equal to the mechanical series resonance frequency f _S of the oscillator. It is possible to set the frequency of the self-excited vibration of the vibrator to a frequency that substantially matches the mechanical series resonance frequency f _S.

Further, according to the second and third aspects of the invention, the mechanical series resonance frequency f _S due to the damping capacity of the vibrator is generated.
Since it is possible to compensate for a slight deviation from, the frequency of the self-excited vibration of the vibrator is determined by its mechanical series resonance frequency f _S.
It is possible to set the frequency that exactly coincides with.

Further, according to the fourth invention for controlling the vibration of the vibrator having substantially a pair of piezoelectric elements, the frequency of the self-excited vibration of the vibrator is substantially equal to the mechanical series resonance frequency f _S thereof. The output of the feedback amplifier corresponding to each piezoelectric element can be stabilized, and the generation and fluctuation of the null voltage can be effectively reduced.

Further, according to the fifth and sixth aspects of the invention, the frequency of the self-excited vibration of the vibrator can be set to the frequency that exactly matches the mechanical series resonance frequency f _S , and the null voltage It is possible to effectively reduce the occurrence and fluctuation.

[Brief description of drawings]

FIG. 1 is a block diagram showing a first embodiment of the present invention.

FIG. 2 is likewise a block diagram showing a second embodiment.

FIG. 3 is a block diagram showing a configuration of an example of the driving device shown in FIG.

FIG. 4 is a block diagram showing a third embodiment of the present invention.

FIG. 5 is a diagram showing an example of measurement of transfer characteristics and phase characteristics in the third embodiment.

FIG. 6 is a block diagram showing a fourth embodiment of the present invention.

FIG. 7 is likewise a block diagram showing a fifth embodiment.

FIG. 8 is likewise a block diagram showing a sixth embodiment.

FIG. 9 is a diagram showing an example of measurement of transfer characteristics and phase characteristics in the sixth embodiment.

FIG. 10 is a block diagram showing a seventh embodiment of the present invention.

FIG. 11 is likewise a block diagram showing an eighth embodiment.

FIG. 12 is likewise a block diagram showing a ninth embodiment.

FIG. 13 is likewise a block diagram showing a tenth embodiment.

FIG. 14 is likewise a block diagram showing an eleventh embodiment.

FIG. 15 is likewise a block diagram showing a twelfth embodiment.

FIG. 16 is likewise a block diagram showing a thirteenth embodiment.

FIG. 17 is likewise a block diagram showing a fourteenth embodiment.

FIG. 18 is a block diagram for explaining a conventional example.

FIG. 19 is a diagram showing a configuration of an example of a vibrator that can be used in the present invention.

FIG. 20 is a diagram similarly showing the configuration of another example.

FIG. 21 is a diagram similarly showing the configuration of still another example.

FIG. 22 is a diagram similarly showing the configuration of still another example.

FIG. 23 is a diagram similarly showing the configuration of still another example.

FIG. 24 is a diagram similarly showing the configuration of still another example.

FIG. 25 is a diagram similarly showing the configuration of still another example.

FIG. 26 is a diagram for explaining display of a vibrator.

FIG. 27 is likewise a diagram for explaining display of a vibrator.

FIG. 28 is a diagram showing a measurement example of frequency characteristics and phase characteristics of admittance of a vibrator.

FIG. 29 is a diagram showing an example of measurement of transfer characteristics and phase characteristics in the conventional example.

FIG. 30 is a diagram showing an equivalent circuit of a vibrator.

[Explanation of symbols]

 1 Vibrating body 2,3,5 Piezoelectric element 4 Vibrator 6 Driving device 10,10L, 10R Feedback amplifier

Claims (14)

[Claims] 1. A vibrator having one piezoelectric element on a side surface of a vibrating body having a resonance point, a driving device having a signal output terminal for outputting a driving signal of the vibrator, a feedback input terminal and a signal input. A feedback amplifier having a terminal, the signal input terminal of the feedback amplifier is coupled to the signal output terminal of the driving device, and the feedback input terminal is coupled to one electrode of the piezoelectric element, and the other of the piezoelectric elements is coupled. The vibration control device is characterized in that the electrode of is connected to the ground. 2. A vibrator having one piezoelectric element on a side surface of a vibrating body having a resonance point, a signal output terminal for outputting a drive signal of the vibrator, and a compensation for outputting a compensation signal for a braking capacitance of the vibrator. A drive device having a signal output terminal, and a feedback amplifier having a feedback input terminal and a signal input terminal, the signal input terminal of the feedback amplifier being a signal output terminal of the drive device, and the feedback input terminal being a feedback input terminal. A vibration control device, wherein each of the electrodes is connected to one electrode of the piezoelectric element, and the other electrode of the piezoelectric element is connected to a compensation signal output terminal of the driving device. 3. A vibrator having one piezoelectric element on a side surface of a vibrating body having a resonance point, a signal output terminal for outputting a drive signal of the vibrator, and a compensation for outputting a compensation signal for a braking capacitance of the vibrator. A drive device having a signal output terminal, and a feedback amplifier having a feedback input terminal and a signal input terminal, the signal input terminal of the feedback amplifier being a signal output terminal of the drive device, and the feedback input terminal being a feedback input terminal. Vibration control characterized in that it is respectively coupled to one electrode of the piezoelectric element, the other electrode of the piezoelectric element is coupled to the ground, and the compensation signal output terminal of the driving device is coupled to the output terminal of the feedback amplifier. apparatus. 4. A vibrator having substantially a pair of piezoelectric elements on a side surface of a vibrating body having a resonance point, a driving device having a signal output terminal for outputting a driving signal of the vibrator, a feedback input terminal and a signal, respectively. And two feedback amplifiers having input terminals, the signal input terminals of the two feedback amplifiers are coupled to the signal output terminals of the driving device, and the feedback input terminal of one feedback amplifier is One of the electrodes of one piezoelectric element, the input terminal for feedback of the other feedback amplifier is respectively coupled to one electrode of the other piezoelectric element, and the other electrode of each of these piezoelectric elements is coupled to the ground. Vibration control device. 5. A vibrator having substantially a pair of piezoelectric elements on a side surface of a vibrating body having a resonance point, a signal output terminal for outputting a driving signal of the vibrator, and a compensating signal for a damping capacitance of the vibrator. A drive device having a compensation signal output terminal;
Two feedback amplifiers each having a feedback input terminal and a signal input terminal, and the respective signal input terminals of these two feedback amplifiers are coupled to the signal output terminal of the driving device, and one feedback amplifier The feedback input terminal of is coupled to one electrode of the one piezoelectric element, the feedback input terminal of the other feedback amplifier is coupled to one electrode of the other piezoelectric element, and the other electrodes of these piezoelectric elements are coupled to each other. A vibration control device coupled to a compensation signal output terminal of the driving device. 6. A vibrator having substantially a pair of piezoelectric elements on a side surface of a vibrator having a resonance point, a signal output terminal for outputting a drive signal of the vibrator, and a compensation signal for a braking capacitance of the vibrator. A drive device having a compensation signal output terminal;
Two feedback amplifiers each having a feedback input terminal and a signal input terminal, and the respective signal input terminals of these two feedback amplifiers are coupled to the signal output terminal of the driving device, and one feedback amplifier The feedback input terminal of is coupled to one electrode of the one piezoelectric element, the feedback input terminal of the other feedback amplifier is coupled to one electrode of the other piezoelectric element, and the other electrodes of these piezoelectric elements are coupled to each other. A vibration control device, wherein the vibration control device is coupled to a ground, and a compensation signal output terminal of the driving device is coupled to each output terminal of the two feedback amplifiers. 7. The vibration control device according to claim 1, wherein the output signal of the feedback amplifier is fed back to the driving device. 8. The vibration control device according to claim 4, wherein the output signals of the two feedback amplifiers are combined and fed back to the drive device. 9. A composite output of a compensation signal from a compensation signal output terminal of the drive device and an output signal of the feedback amplifier,
The vibration control device according to claim 3, wherein the vibration control device is returned to the drive device. 10. The combined output of the compensation signal from the compensation signal output terminal of the driving device and the output signal of each of the two feedback amplifiers is fed back to the driving device. Vibration control device. 11. The drive device is configured to change an amplitude and a phase of a compensation signal output from the compensation signal output terminal in accordance with a value of a braking capacity of the vibrator. The vibration control device according to 2, 3, 5, 6, 9 or 10. 12. The vibration control device according to claim 4, further comprising a differential amplifier that detects a difference between output signals of the two feedback amplifiers. 13. The drive device includes a capacitor having a temperature dependence corresponding to the temperature dependence of the damping capacitance of the vibrator, and the amplitude and phase of the compensation signal output from the compensation signal output terminal by the capacitor. The vibration control device according to claim 2, 3, 5, 6, 9, 10 or 11, wherein is configured to be changed according to the temperature dependence of the braking capacity of the vibrator. 14. The vibration control device according to claim 2, 3, 5, 5, 6, 9, 10, 11 or 13, wherein the capacitor is made of the same composition as the piezoelectric element.