JPH11164574A - Oscillatory actuator driver - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable adjustment of velocity difference by shifting direction. SOLUTION: An oscillatory actuator driver is constituted of an oscillatory actuator 10, equipped with an elastic body 11 and an electromechanical converting element 12 jointed with an elastic body, and a drive circuit 20 for harmonically generating plural oscillation modes by applying a two-phase AC voltage to an electromechanical converting element 12. The drive circuit 20 is equipped with a phase difference adjusting circuit 26 for adjusting the phase difference between two-phase AC voltages.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of vibrating a vibrator by an electromechanical transducer (piezoelectric element, electrostrictive element, etc .; hereinafter, typically referred to as a piezoelectric element) to generate a plurality of vibration modes harmoniously. The present invention relates to a vibration actuator (hereinafter, representatively referred to as an ultrasonic actuator) that causes an elliptical motion on the surface of a vibrator to cause the vibrator to run on its own or to drive a moving body that comes into contact with the vibrator. .

[0002]

2. Description of the Related Art Conventionally, an ultrasonic actuator of this type is driven by, for example, applying an AC voltage to a piezoelectric element bonded to an elastic body to generate longitudinal vibration and bending vibration in the elastic body in harmony. The one that gains power is being developed,
The configuration and load characteristics are disclosed in "Piezoelectric Linear Motor for Moving Optical Pickup" (Yoshihiro Tomikawa et al .: Proceedings of the 5th Dynamic Symposium on Electromagnetic Force, pp. 393-398). In addition, a self-propelled device is shown in a new edition ultrasonic motor (Sadayuki Ueba, Yoshiro Tomikawa, pp145-146, published by Trikeps).

In this ultrasonic actuator, the elastic body has a flat plate shape, and is designed to have a shape in which the resonance frequencies of the first-order longitudinal vibration mode and the fourth-order (or eighth-order mode) bending vibration have very close values. ing. Then, an AC voltage having a frequency close to the two resonance frequencies is applied to the piezoelectric element in two phases (a phase difference of 90).
°) When applied, the elastic body generates vibration in which the two modes are in harmony. The elastic body is provided with a protrusion at the antinode of the fourth mode of the bending vibration, and a driving force can be obtained by the elliptical movement of the tip of the protrusion. In addition, you may make it stick a sliding material instead of a protrusion part. By setting the phase difference between the two phases to 90 ° or −90 °, the driving direction is reversed.

[0004] In this ultrasonic actuator, the resonance frequency of the first mode of longitudinal vibration and the fourth mode of bending vibration of a flat elastic body is given by the following equation.

[0005]

(Equation 1)

Since this vertical-bending type ultrasonic actuator is symmetrical, when processed into an ideal shape, the velocity when the phase difference of the applied voltage is 90 ° and −90 ° is obtained. (Hereinafter referred to as the difference between the left and right speeds) is zero.

[0007]

However, in the conventional ultrasonic actuator described above, the dimensional error at the time of processing the elastic body, the variation in the characteristics of the piezoelectric element, and the bonding when the piezoelectric element and the sliding material are bonded. Since the left and right sides are not necessarily symmetric due to a positional shift or the like, the form of the generated vibration differs depending on the case where the phase difference is 90 ° and the case where the phase difference is −90 °. There was a problem.

An object of the present invention is to provide a vibration actuator driving device capable of adjusting a speed difference depending on a moving direction.

[0009]

According to a first aspect of the present invention, there is provided an electromechanical transducer and a driving force for extracting a driving force obtained by vibration generated by the electromechanical transducer. A vibration actuator for generating a relative movement in at least two directions with a relative motion member contacting the driving force extraction unit by the driving force, and at least two-phase alternating current to the electromechanical conversion element. A drive circuit that applies a voltage to generate a plurality of vibration modes in harmony, and adjusts a waveform of the AC voltage to change a vibration direction of the vibration actuator in a first direction or a second direction. A waveform adjustment circuit that sets a desired state by making the drive speed difference equal or different,
A vibration actuator driving device including:

According to a second aspect of the present invention, in the vibration actuator driving device according to the first aspect, the waveform adjustment circuit adjusts the value of the parameter of the waveform in advance,
Provided is a vibration actuator driving device that makes a speed difference according to a moving direction when the vibration actuator moves in a first or second direction equal or different.

According to a third aspect of the present invention, in the vibration actuator driving device according to the first aspect, the ambient temperature, the frequency of the AC voltage, and the relative speed with respect to a relative motion member that performs relative motion with the vibration actuator. A detector for detecting a state value including at least one of the following: the drive circuit includes a parameter variable unit for changing a value of a parameter of a waveform of the AC voltage, and the waveform adjustment circuit includes: And a storage circuit for storing an optimum parameter value for the parameter, based on a detection result of the detector, obtaining an optimum parameter value from the storage circuit, and changing the parameter value of the parameter variable device to the optimum parameter value. And a parameter changing circuit for changing the parameter.

According to a fourth aspect of the present invention, there is provided the vibration actuator driving apparatus according to the third aspect, further comprising a writing device for writing an optimum parameter value for the state value into the storage circuit. .

According to a fifth aspect of the present invention, in the vibration actuator driving device according to the first aspect, the waveform adjustment circuit is a phase difference adjustment circuit for adjusting a phase difference between the two-phase AC voltages. I will provide a.

According to a sixth aspect of the present invention, in the vibration actuator driving device according to the fifth aspect, the phase difference adjusting circuit adjusts the phase difference in advance so that the vibration actuator moves in the first or second direction. Provided is a vibration actuator driving device that makes a speed difference depending on a moving direction when moving the same or different.

According to a seventh aspect of the present invention, in the vibration actuator driving device according to the sixth aspect, the ambient temperature, the frequency of the AC voltage, and the relative speed with respect to the relative motion member which performs relative motion with the vibration actuator. A detector that detects a state value including at least one of the following: the drive circuit includes a phase shifter that changes a phase of the AC voltage, and the phase difference adjustment circuit includes an optimal phase shifter for the state value. A storage circuit for storing a phase difference, and a phase difference changing circuit for obtaining an optimum phase difference from the storage circuit based on a detection result of the detector, and changing a phase difference of the phase shifter to the optimum phase difference. And a vibration actuator driving device including:

According to an eighth aspect of the present invention, there is provided the vibration actuator driving device according to the seventh aspect, further comprising a writing device for writing an optimum phase difference with respect to the state value in the storage circuit.

According to a ninth aspect of the present invention, there is provided the vibration actuator driving device according to the first aspect, wherein the waveform adjustment circuit is a frequency adjustment circuit for adjusting the frequency of the two-phase AC voltage. I do.

According to a tenth aspect of the present invention, in the vibration actuator driving device according to the ninth aspect, the frequency adjustment circuit includes a shift amount from an anti-resonance frequency of the vibrator including the vibrator and the electromechanical transducer. The present invention provides a vibration actuator driving device for adjusting the pressure.

According to an eleventh aspect of the present invention, in the vibration actuator driving device according to the tenth aspect, the frequency adjustment circuit adjusts a frequency shift amount in advance so that the vibration actuator can move in the first or second direction. Provided is a vibration actuator driving device that makes the speed difference according to the moving direction when moving to the same or different.

According to a twelfth aspect of the present invention, in the vibration actuator driving device according to the tenth aspect, a surrounding temperature, a frequency of the AC voltage, and a relative movement member which performs relative movement with the vibration actuator. A detector for detecting a state value including at least one of speeds, the driving circuit includes an oscillator for oscillating the AC voltage at a predetermined frequency, and the frequency adjusting circuit includes an optimum oscillator for the state value. A storage circuit for storing a frequency shift amount, and a frequency shift for obtaining an optimum frequency shift amount from the storage circuit based on a detection result of the detector and changing the frequency shift amount of the oscillator to the optimum frequency shift amount. A vibration actuator driving device including a quantity changing circuit is provided.

According to a thirteenth aspect of the present invention, there is provided the vibration actuator driving device according to the twelfth aspect, further comprising a writing device for writing an optimum frequency shift amount with respect to the state value in the storage circuit. I do.

According to a fourteenth aspect of the present invention, there is provided the vibration actuator driving device according to the first aspect, wherein the waveform adjustment circuit is a voltage adjustment circuit for adjusting the voltage of the two-phase AC voltage. I do.

According to a fifteenth aspect of the present invention, in the vibration actuator driving device according to the fourteenth aspect, the voltage adjusting circuit adjusts a voltage in advance so that the vibration actuator moves in the first or second direction. Provided is a vibration actuator driving device that makes the speed difference according to the moving direction coincide or differs.

According to a sixteenth aspect of the present invention, in the vibration actuator driving device according to the fourteenth aspect, the ambient temperature, the frequency of the AC voltage, and the relative movement with respect to the relative movement member that performs relative movement with the vibration actuator. A detector for detecting a state value including at least one of speeds, the driving circuit includes an amplifier for amplifying the voltage of the AC voltage at a predetermined amplification factor, and the voltage adjusting circuit includes: A storage circuit that stores an optimal voltage for the gain, and an amplification factor change that obtains an optimal voltage from the storage circuit based on a detection result of the detector and that changes an amplification factor of the amplification so that the optimal voltage is obtained. And a vibration actuator driving device including the circuit.

According to a seventeenth aspect of the present invention, there is provided the vibration actuator driving device according to the sixteenth aspect, further comprising a writing device for writing an optimum amplification factor for the state value into the storage circuit. .

[0026]

Embodiments of the present invention will be described below in more detail with reference to the drawings. In the embodiments described below, the vibration actuator will be described as an example of an ultrasonic actuator driven in an ultrasonic region. (First Embodiment) FIG. 1 is a view showing a first embodiment of a vibration actuator driving device according to the present invention.
1A is a perspective view showing the ultrasonic actuator 10 alone, and FIG. 1B is a side view showing the ultrasonic actuator 10.

The ultrasonic actuator 10 according to the first embodiment
Includes a vibrator 11, a relative motion member 50 for causing relative motion between the vibrator 11, and pressurizing means 30 for pressing the vibrator 11 and the relative motion member 50 into contact.
The vibrator 11 includes an elastic body 12 and four piezoelectric elements 13a, 13b, 13p, 1 joined to one surface of the elastic body 12.
3p '. The piezoelectric elements 13a and 13b are driving elements that vibrate the elastic body 12 by a piezoelectric effect. Further, the piezoelectric elements 13p and 13p 'are
This is an element for monitoring the state of the vibration generated in the device. In addition,
The elastic body 12 is connected to the GND potential.

The elastic body 12 has driving force extracting portions 12a and 12b which generate elliptical motion at the tip thereof at the position of the antinode of the bending vibration on the other surface (the opposite surface to which the piezoelectric element 13 is joined).
Are formed. In addition, the driving force extracting portions 12a, 12b
May be formed integrally with the elastic body 12 main body,
It may be formed by attaching a sliding material.

The ultrasonic actuator 10 is configured such that the driving force extracting portions 12a and 12b and the relative motion members (rails, rollers, etc.) 50 are brought into contact with each other under pressure by the pressing means 30 to thereby obtain the driving force extracting portions 12a. , 12b.

FIG. 2 is a block diagram showing a driving circuit 20 of the vibration actuator driving device according to the first embodiment of the present invention. The drive circuit 20 includes an oscillator 21 for generating a drive signal having an AC voltage of a predetermined frequency, and a phase shifter 22 for converting one output of the oscillator 21 by a phase difference φ.
And an amplifier 23 that amplifies the output of the phase shifter 22 and connects to the piezoelectric element 13a, an amplifier 24 that amplifies the other output of the oscillator 21 and connects to the piezoelectric element 13b, and piezoelectric elements 13p and 13p '. And a control circuit 25 for controlling the voltage or frequency of the drive signal of the oscillator 21 based on the output of the oscillator 21.

In this vibration actuator driving device, the driving force of the elastic body 12 is extracted by applying an AC voltage having a phase different from φ (φ = 90 ° for an ideal vibrator) to the piezoelectric elements 13a and 13b. An elliptical motion is generated at the tips of the portions 12a and 12b. Then, a driving force is obtained by bringing the driving force extracting portions 12a and 12b of the elastic body 12 into pressure contact with the relative movement member 50.

The drive circuit 20 of this embodiment further includes:
A phase difference adjusting circuit 26 for adjusting the phase difference φ of the phase shifter 22 is provided.

FIG. 3 is a diagram showing the relationship between the phase difference and the speed of the vibration actuator driving device according to the first embodiment of the present invention. The phase difference φ indicates a phase difference between an AC voltage applied to the piezoelectric element 12a and an AC voltage applied to the piezoelectric element 12b. Here, the direction of the velocity is assumed to be positive when the ultrasonic actuator 10 shown in FIG.

In FIG. 3, if the phase difference φ = 90 °, the speed v = 130 [mm / s] and φ = −90.
When the angle is set to v, v = −90 [mm / s], and the difference between the left and right speeds is 40 [mm / s]. That is, FIG.
As shown by the arrow in the middle, it is understood that the speed before adjustment (the speed when the ultrasonic actuator 10 moves with respect to the relative motion member 50) differs depending on the moving direction.

In the present embodiment, the phase difference adjustment circuit 26 adjusts the phase difference φ of the phase shifter 22 to 60 ° when traveling in the positive direction, and to −70 ° when traveling in the negative direction. I did it. For this purpose, each speed v = 10
0, -100 [mm / s], and the difference between the left and right speeds was almost zero.

According to the first embodiment, the phase difference adjusting circuit 2
According to 6, the phase difference φ is adjusted at the time of the adjustment work before shipping, so that the difference between the left and right speeds of the ultrasonic actuator 10 can be corrected. For this reason, the phase difference φ is set to an appropriate value at the time of shipment, and the value is always used during operation. Therefore, various mechanical asymmetries that occur in the ultrasonic actuator 10 during manufacturing can be electrically corrected. As a result, it is possible to improve the yield rate of the ultrasonic actuator.

(Second Embodiment) FIG. 4 shows a driving circuit 2 of a vibration actuator driving device according to a second embodiment of the present invention.
It is a block diagram showing 0-2. In the embodiments described below, parts performing the same functions as in the first embodiment are given the same reference numerals or the same reference numerals at the end, and duplicate drawings and descriptions are omitted as appropriate. I do. The phase difference adjusting circuit 26-2 according to the second embodiment is configured such that the phase difference φ is dynamically adjusted based on the ambient temperature, the frequency of the AC voltage, the state speed of the relative moving member 50, and the like. It was made.

The detector 27 is a detector that detects at least one of the above-mentioned state values such as temperature, frequency and speed. The writing device 28 is a device that writes an optimum phase difference with respect to the state value to the storage circuit 26a.

The phase difference adjusting circuit 26-2 includes a memory circuit 26.
a and a phase difference changing circuit 26b. Storage circuit 2
6a, a table indicating the relationship between the state value and the optimal phase difference is written by the writing device 28 in the adjustment stage before shipment. The phase difference changing circuit 26b obtains an optimum phase difference from a table of the storage circuit 26a based on a detection value such as a temperature signal, a frequency signal, or a speed signal detected by the detector 27. Then, the phase shift amount of the phase shifter 22 is controlled based on the obtained optimal phase difference.

According to the second embodiment, the optimum phase difference is calculated from the table of the storage circuit 26a based on the detected value of the temperature signal, the frequency signal or the speed signal detected by the detector 27, and the phase shift is performed. The phase shift amount of the device 22 is controlled. Therefore, it is possible to adjust the difference between the left and right speeds of the ultrasonic actuator 10 even when the environmental state changes during operation.

(Third Embodiment) FIG. 5 is a longitudinal sectional view showing the structure of a vibration actuator driving device according to a third embodiment of the present invention, and FIG. 6 shows a driving circuit 40 of the vibration actuator driving device of FIG. FIG. 7A is a block diagram, and FIG.
FIG. 7B is a diagram of the vibrator formed by the two semi-cylindrical elastic bodies shown in FIG. 7 when viewed from the bottom surface direction, and FIG. 7B is a diagram of the vibrator shown in FIG. In the third embodiment, the torsional-longitudinal vibration type ultrasonic actuator 1 is driven.

In the ultrasonic actuator 1, the vibrator 2 includes elastic members 2a and 2b and piezoelectric elements 3 and 4. The elastic bodies 2a and 2b are members having a shape obtained by vertically dividing a thick hollow cylinder into two, and are held in a state where the piezoelectric elements 3 and 4 are sandwiched between the divided surfaces. The piezoelectric elements 3 and 4 are electromechanical transducers that are excited by drive signals and convert electric energy into mechanical displacement.

The elastic bodies 2a and 2b have through holes 2d and 2 at substantially the center in the height direction in parallel with the lamination direction of the piezoelectric elements 3 and 4.
e is formed. The elastic bodies 2a, 2b are fixed by bolts 6a, 6b using the through holes 2d, 2e. As a result, the piezoelectric elements 3 and 4 are sandwiched and screwed to the fixed shaft 5 inserted at the center in the axial direction.

The moving element (relative moving member) 7 includes a moving element base material 7-1 and a sliding material 7-contacting the driving surface 2c of the vibrator 2.
2 is constituted. The mover 7 is a mover base material 7
-1 is positioned with respect to the fixed shaft 5 by a bearing (positioning member) 8 fitted in the inner peripheral portion. Further, the moving element 7 is brought into pressure contact with the driving surface 2c of the vibrator 2 by the pressure member 9a.

The fixed shaft 5 penetrates a hollow portion formed in the elastic body 2a, 2b in the axial direction. The fixed shaft 5 fixes the vibrator 2 and positions the moving element 7 in the radial direction. The fixed shaft 5 has a screw portion 5a formed at an end thereof, and a nut (pressing force adjusting member) 9b for adjusting the pressing force of the pressing member 9a is screwed.

As shown in FIG. 6, the drive circuit 40 includes an oscillator 41 for oscillating a drive signal, a phase shifter 42 for dividing the drive signal into signals having a phase difference, and a torsional vibration piezoelectric element 3. A T-amplifier 43 for amplifying a drive signal to be input, an L-amplifier 44 for amplifying a drive signal to be input to the longitudinal vibration piezoelectric element 4, and control of the frequency and voltage of the oscillator 41 according to the detection amount of a detector 47 A control circuit 45, a phase difference adjusting circuit 46 for adjusting the phase difference of the phase shifter 42, a detector 47 for detecting torsional vibration, and the like are provided.

The detector 47 includes a piezoelectric element 47a attached to a side surface of the vibrator 2, and detects a displacement generated due to the torsion to thereby generate an indirectly generated torsion. This is a structure for detecting displacement.

As shown in FIGS. 7A and 7B, the piezoelectric elements 3 and 4 are composed of two groups sandwiched between two piezoelectric elements 2a and 2b. Each of the four layers is composed of a piezoelectric element 3 using a piezoelectric constant d ₁₅ , and the remaining two layers are composed of a piezoelectric element 4 using a piezoelectric constant d ₃₁ . Since the former piezoelectric element 3 uses the piezoelectric constant d ₁₅ , it is excited to generate a shear displacement in the longitudinal direction of the elastic bodies 2 a and 2 b. In FIG. 7A, the piezoelectric elements 3 are arranged such that the shearing deformation alternates in the front direction X and the opposite direction Y with respect to the circumferential direction. Piezoelectric element 3
By disposing in this manner, when each is subjected to shear deformation, a torsional displacement is generated in the vibrator 2 and the bottom surface is twisted.

The latter piezoelectric element 4, because of the use of piezoelectric constant d _31, the elastic body 2a, to generate the elastic displacement with respect to the longitudinal direction of 2b. The four piezoelectric elements 4 for longitudinal vibration are all arranged so that displacement occurs in the same direction when a certain potential is applied.

The ultrasonic actuator 1 is connected to an L amplifier 4 via an oscillator 41 and a phase shifter 42 in FIG.
A drive signal is applied to the piezoelectric elements 3 and 4 from the 3 and T amplifiers 44. Then, the piezoelectric elements 3 and 4 are excited, and the elastic body 2 generates torsional vibration and longitudinal vibration.

According to the third embodiment, the phase difference adjusting circuit 46 for adjusting the phase difference of the phase shifter 42 is provided, and the phase difference φ is adjusted at the time of the adjustment work before shipping. It is possible to correct the left-right difference (speed difference in the forward and reverse rotation directions) of the speed of the acoustic wave actuator 1.

(Fourth Embodiment) FIG. 8 is a sectional view showing a configuration of an ultrasonic actuator 10B according to a fourth embodiment of the present invention. FIG. 9 is a perspective view showing the configuration of the ultrasonic actuator 10B. The ultrasonic actuator 10B of the fourth embodiment includes a vibrator 11 and a vibrator 1
1 is provided with a relative movement member 51 that generates relative movement between the vibration member 11 and the pressure mechanism 32 having a pressure member 32 that presses the vibrator 11 and the relative movement member 51 under pressure.

The vibrator 11 includes an elastic body 12 and an elastic body 12.
And a piezoelectric element 13 mounted on one of the flat surfaces. In the present embodiment, the elastic body 12 is formed in a rectangular flat plate shape by SUS304. The dimensions of each part of the elastic body 12 are the primary longitudinal vibration L1 and the fourth-order bending vibration B4.
The natural frequencies are set so as to be substantially the same. The elastic body 12 may be formed of a metal material having a large resonance sharpness, such as steel, stainless steel, phosphor bronze, or an elinvar material, other than stainless steel.

On one plane of the elastic body 12, a piezoelectric element 13 to be described later is mounted, for example, by bonding. Also,
On the other plane of the elastic body 12, two grooves in the width direction of the elastic body 12 are provided at a predetermined distance from each other in the relative movement direction (the left-right direction in FIG. 8). A sliding member having a rectangular cross-sectional shape is fitted into these grooves, adhered with an epoxy-based adhesive, and mounted in a protruding manner.

Then, the sliding material is used as the driving force take-out portion 12.
Functions as a and 12b. Therefore, the elastic body 12
Are driving force take-out portions 12a, 12b made of these sliding members.
And the relative motion member 51 is contacted. In this embodiment, the sliding material is a resin having PTFE as a matrix.
It is made of a material (trade name: Polyflon, Daikin Industries, Ltd.) in which 5% by weight of glass fiber and 5% by weight of molybdenum disulfide are mixed.

FIG. 10 shows a longitudinal vibration L generated in the vibrator 11.
It is explanatory drawing which shows 1 and bending vibration B4. The driving force output members 12a, 12b are positioned to match the loop position m _1, m ₄ is located outside of the four loop position m ₁ ~m ₄ fourth-order bending vibration B4 generated in the elastic member 12 Is provided.
The driving force output portions 12a, 12b need not in a position to exactly match the loop position m _1, m ₄ bending vibration B4, may be in the vicinity of the antinode position.

In this embodiment, the piezoelectric element 13 is made of PZT
(Lead titanium zirconate, registered trademark). This piezoelectric element 13 includes
Input areas 13a and 13c to which an A-phase drive signal is input
And input regions 13b and 13d to which a drive signal of the phase B which is shifted from the phase A by (π / 2) are formed. Each input region 13a~13d, as shown in FIG. 10, are formed in four regions partitioned by five nodal position n ₁ ~n ₅ of the bending vibration B4 generated in the elastic body 12. In other words, each of the input areas 13a to 13d that are deformed by the input of the drive signal is a node position n that is a fixed point.
Order not cross the ₁ ~n _5, there is no deformation of the input area 13a~13d is suppressed by nodal positions n ₁ ~n _5.
Therefore, the electric energy input to each of the input areas 13a to 13d is transformed with maximum efficiency into the deformation of the elastic body 12, that is, converted into mechanical energy.

At the nodal positions n ₂ and n ₄ of the bending vibration B4, detection areas 13p and 13p 'for outputting electric energy by the longitudinal vibration L1 generated by the vibrator 11 are provided in a semicircular shape. Thereby, the vibration state of the longitudinal vibration L1 generated by the vibrator 11 is detected.

Each of the input areas 13a to 13d and each of the detection areas 1
3p and 13p 'mean that each surface is a silver electrode 15a.
~ 15d, 15p, 15p '. As a result, it is possible to input a drive signal to each of the input regions 13a to 13d independently, and to output a detection signal independently from each of the detection regions 13p and 13p '.

FIG. 11 is a block diagram showing a vibration actuator driving device according to a fourth embodiment of the present invention. The vibration actuator driving device includes a driving circuit 114,
A power supply circuit 116, a current detection circuit 118, an analog / digital converter (hereinafter, A / D converter) 120, a processing circuit 122, a digital / analog converter (hereinafter, D / A converter) 124, Oscillator (hereinafter VCO) 12
6, a frequency divider 128, and a direction switching circuit 130.

Processing circuit 122, D / A converter 124, V
CO 126, frequency divider 128, and direction switching circuit 130
Accordingly, a frequency sweeper for sweeping the frequency of the AC voltage signals DRV1 and DRV2 is configured, and a control device for stopping the sweep operation of the frequency sweeper from the A / D converter 120 and the processing circuit 122 is configured.

The drive circuit 114 drives the ultrasonic actuator 10B by applying AC voltage signals DRV1, DRV2 to it. Power supply circuit 116, generates a drive voltage + V _D and -V _D supplied with a voltage V _S from the outside is supplied to the drive circuit 114, the current detection circuit 118, the power supply circuit 11
6, and outputs a voltage signal _VDI corresponding to the detected current value.

The A / D converter 120 receives the voltage signal _VDI , converts the voltage value of the voltage signal _VDI into a digital value, and outputs the digital value to the processing circuit 122. The processing circuit 122 outputs a sweep instruction of the frequency of the AC voltage signals DRV1 and DRV2 in response to an external run-stop signal (R / S signal), and outputs the instruction from the A / D converter 120 input at predetermined sampling intervals. Based on the output digital voltage value, it is determined whether a condition for stopping the frequency sweep has occurred, and the frequency sweep is stopped. The D / A converter 124 converts the digital value signal output when the processing circuit 122 sweeps the frequency of the AC voltage signals DRV1 and DRV2 into the analog voltage signal V
_The VCO 126 converts the clock signal CLK into a clock signal CLK having a frequency (= 4f) corresponding to the voltage value of the analog voltage signal V _IN.
Outputs 0.

The frequency divider 128 generates a clock signal CLK1 and a clock signal CL of the drive frequency (= f) of the ultrasonic actuator 10B based on the clock signal CLK0.
A clock signal CLK2 having the same frequency as K1 and a phase different by 90 ° is output. The direction switching circuit 130 receives the clock signal CLK2, and outputs a clock signal CLK3 which is the same signal as the clock signal CLK2 or an inverted signal of the clock signal CLK2 in response to an external direction instruction signal (hereinafter, an R / L signal). Output.

The drive circuit 114 generates the clock signal CLK1
And a driver 134-1 for amplifying and outputting an AC voltage signal DRV1, and a clock signal CLK3,
A driver 134-2 that performs level conversion and outputs an AC voltage signal DRV2.

FIG. 12 is an explanatory diagram showing the detection position of the driving current. The power supply circuit 116 is the ultrasonic actuator 1
Since operating energy is supplied to 0B, the driving current of the ultrasonic actuator 10B and the operating current of the power supply circuit 116 have the same frequency dependence. Therefore,
When the point A shown in FIG.
By detecting the value of the current flowing through the terminal to which _S is supplied, the drive current of the ultrasonic actuator 10B can be detected.

FIG. 13 is a circuit diagram showing the current detection circuit 118 when the point A in FIG. 12 is set as a current detection point. As shown in FIG. 13, this current detection circuit 118
With an operational amplifier AMP1 and resistors R2~R5 are configured in combination, and further comprising a voltage source for supplying the operating bias voltage V _B of (-E _B). In the current detection circuit 118, changes according to the current value I _S flowing through the terminal to which the voltage V _S is supplied, the voltage value V is a voltage value in the vicinity of _S voltage value _{V A (= V S -R 1} · I _S ) Detect. Then, it outputs a voltage signal _VDI having a voltage value around the ground level according to the detected voltage value. Incidentally, the degree of approach to the ground level varies according to the voltage value of the operating bias voltage V _B.

Returning to FIG. 11, the VCO 126 outputs the clock signal CLK0 having a frequency (= 4f) according to the applied voltage value, but has a characteristic that the output frequency decreases as the applied voltage value increases. ing. Processing circuit 1
22 can be constituted by a microprocessor and its peripheral circuits.

Hereinafter, the driving method of the vibration actuator according to the present embodiment will be described together with the operation of the driving circuit of the vibration actuator according to the present embodiment. FIG. 14 is a timing chart illustrating the operation of the vibration actuator driving device according to the present embodiment.

As shown in FIG. 14, first, the operation direction of the ultrasonic actuator 10B is instructed by the R / L signal in a state where the R / S signal is the stop instruction.

The direction switching circuit 130 according to the R / L signal
Outputs the input clock signal CLK2 as it is as the clock signal CLK3, or outputs the clock signal CLK2.
Is output.

Next, the R / S signal changes to a run instruction, and the driving of the ultrasonic actuator 10B starts. That is, the processing circuit 122 monitoring the R / S signal outputs
When detecting that the S signal has been changed to the run instruction, the processing circuit 122 outputs to the D / A converter 124 while sequentially increasing the digital signal whose voltage value to be output is represented by a digital value. D /
The A converter 124 outputs the analog signal V of the designated voltage value.
Output _IN .

Upon receiving the voltage signal V _IN , the VCO 126
A clock signal CLK0 having a frequency (= 4f) according to the applied voltage value is output. Here, since the voltage value of the voltage signal V _IN increases with time, the clock signal CL
The frequency of K0 is swept from the high frequency side to the low frequency side. The clock signal CLK0 is frequency-divided by the frequency divider 128, both of which have the frequency f, and the phases of which are different from each other by 90 °.
Is generated. The clock signal CLK2 is supplied to the direction switch 1
The signal 30 is output as CLK3 as it is or inverted.

The clock signal CLK1 is supplied to the drive circuit 114
Is converted into a level of ± V _D by the driver 134-1 and supplied to the ultrasonic actuator 10B as an AC voltage signal DRV1. On the other hand, the clock signal CLK
3 is controlled by the driver 134-2 of the drive circuit 114.
The level is converted to ± V _D level and the AC voltage signal DRV2
Is supplied to the ultrasonic actuator 10B. Thus, the ultrasonic actuator 10B is driven while the drive frequency (= f) is swept.

In parallel with the above-described sweeping of the drive frequency, the current detection circuit 118 detects the value of the drive current in the power supply circuit 116. This detection result is output from the current detection circuit 118 as a voltage signal _VDI , and A / A
The signal is converted into a digital signal by the D converter 120 and notified to the processing circuit 122. The processing circuit 122
The digital voltage value output from the / D converter 120 is determined based on the digital voltage value output from the A / D converter 120 input at predetermined sampling intervals to determine whether or not a condition for stopping the frequency sweep has occurred. I do. Then, when the stop condition occurs, the frequency sweep is stopped.

Here, the sweeping of the frequency may be stopped when the sampled value becomes substantially the same value for two consecutive times, or when the sampled value becomes larger than the previous sampled value, the frequency sweep may be stopped. The sweep may be stopped, or the frequency sweep may be performed when the average value of the predetermined number of consecutively sampled values becomes larger than the average value of the previous predetermined number of continuously sampled values. You may stop.

If the sampling of the frequency is stopped when the sampled value becomes substantially the same value for two consecutive times,
When the drive frequency f becomes the anti-resonance frequency, the frequency sweep is stopped. Therefore, since the ultrasonic actuator 10B is driven at the anti-resonance frequency, the driving current is reduced and the ultrasonic actuator 10B is driven.
B can be driven. Here, the processing circuit 122
In the shipping stage, the relationship between the driving direction and the shift amount from the anti-resonance frequency is adjusted according to the left / right difference of the ultrasonic actuator itself. Thereby, during operation, the amount of shift from the anti-resonance frequency is adjusted and the ultrasonic actuator 1
0B can be driven in a state where the difference between the left and right speeds is small.

[0078] It is also possible to stop the sweeping after the driving frequency after the above stop condition occurs swept by a few tens of H _Z ~ several hundred H _Z. In this case, it is more certain that the frequency becomes equal to or lower than the anti-resonance frequency.

As described above, when the frequency sweep is stopped, the ultrasonic actuator 10B is stopped at the frequency at the stop.
Is driven. Thereafter, when the R / S signal changes to a stop instruction, the operation of the frequency divider 128 stops immediately, and the driving ends. At the same time, the current value detected by the current detection circuit 118 becomes substantially zero. When the processing circuit 122 monitoring the R / S signal detects that the R / S signal has been changed to the stop instruction, the processing circuit 122 sends the signal to the D / A converter 124.
A digital value is output so that the voltage value to be output is an initial value in sweeping the frequency to prepare for the next drive instruction.

According to the fourth embodiment, since the ultrasonic actuator 10B is driven near the anti-resonance frequency, the driving efficiency is good. Further, since the shift amount of the drive frequency from the anti-resonance frequency is controlled, the ultrasonic actuator 1 is not affected by a change in the environmental state that occurs during operation.
The difference between the left and right speeds of 0B can be adjusted.

(Fifth Embodiment) FIG. 15 shows a fifth embodiment of the present invention.
FIG. 3 is a block diagram illustrating a drive circuit 60 of the vibration actuator drive device according to the embodiment. In addition, the following fifth and sixth
In the embodiment, an example will be described in which the ultrasonic actuator 10B of the fourth embodiment is driven. The oscillator 61 generates an AC voltage drive signal having a frequency corresponding to each of the longitudinal vibration L1 and the bending vibration B4 of the vibrator 11. The output of the oscillator 61 is branched and one output is connected to the phase shifter 6.
2, the phase is shifted from the B-phase voltage by (π / 2) to become the A-phase voltage.
a, 13c are input to the silver electrodes 15a, 15c. The other branched output is amplified by the amplifier 64 and then input as a B-phase voltage to the silver electrodes 15b and 15d of the input regions 13b and 13d.

The control circuit 65 includes detection areas 13p and 13p.
The output voltage of p 'is input. This control circuit 65
Is to lower the frequency when the output of the detection areas 13p and 13p 'is smaller than the reference voltage set in advance, while increasing the frequency when the output of the detection areas 13p and 13p' is higher. As
This is a circuit for controlling the oscillator 61. Thus, the vibration amplitude of the vibrator 11 is maintained at a predetermined value.

As described above, the A-phase AC voltage signal having the frequency corresponding to the natural frequency of each of the longitudinal vibration L1 and the bending vibration B4 is input to the input areas 13a and 13c of the piezoelectric element 13, and 13b, 13d
, A B-phase AC voltage signal having a phase difference of (π / 2) from the A-phase is input. Then, as shown in FIG. 10, a first-order longitudinal vibration L1 and a fourth-order bending vibration B4 are simultaneously generated in the elastic body 12. These vibrations are combined to generate an elliptical motion in the driving force output units 12a and 12b. The current detectors 69A and 69B detect the current values of the AC voltages output from the amplifiers 63 and 64, and the detected values are connected to the control circuit 65.

The shift amount adjuster 66 is a circuit for adjusting the frequency shift amount based on the phase difference information from the phase shifter 62 and the information obtained from the detector 67. 65. Then, the control circuit 65 shifts the driving frequency of the oscillator 61 based on the frequency shift amount output from the shift amount adjuster 66.

FIG. 16 is a block diagram showing in detail the shift amount adjuster 66 of FIG. The shift amount adjuster 66
This circuit dynamically adjusts the frequency shift amount in the driving state based on state values such as the relative speed with respect to the relative motion member 51, the frequency of the AC voltage, and the ambient temperature.

The detector 67 is a detector for detecting at least one of the above-mentioned state values such as speed, frequency and temperature. The writing device 68 is a device for writing the optimum phase difference with respect to the state value in the storage circuit 66a.

The shift amount adjuster 66 stores a table indicating the relationship between the above-mentioned parameters (state values) and the corresponding optimum shift amounts in the adjustment stage before shipment.
8 and a frequency shift amount adjustment circuit 66b that calculates an optimum shift amount based on the parameter value detected by the detector 67 and controls the drive frequency shift amount. .

FIG. 17 is a diagram showing the relationship between the driving frequency and the speed of the vibration actuator driving device according to the fifth embodiment of the present invention. The speed (1) graph shows that the phase difference is 90
°, the speed (2) graph shows that the phase difference is -90.
It shows the relationship when the angle is set to °. The frequency at which the current is minimized is the anti-resonance frequency (4 in FIG. 17).
8.2 [kHz]). The anti-resonance frequency can be found from a change in the current value detected by the current detectors 69A and 69B when the drive frequency is swept. In FIG. 17, if the driving frequency is 48.2 [kHz] (anti-resonance frequency) and the phase difference is 90 °,
When the speed is 150 [mm / s] and -90 °,
The speed is 120 [mm / s], and the difference between left and right is 30 [m
m / s].

Therefore, in the fifth embodiment, the shift amount is adjusted by the shift amount adjuster 66 so that the driving frequency when driving with a phase difference of -90 ° becomes 48.15 [kHz]. . Therefore, when the phase difference is 90 °, the shift amount from the anti-resonance frequency is 0 [Hz], and when the phase difference is −90 °, the shift amount from the anti-resonance frequency is 50 [Hz]. And the difference between the left and right speeds can be reduced to zero.

According to the fifth embodiment, the optimum shift amount is calculated based on the value of the parameter detected by the detector 67, and the shift amount of the driving frequency is controlled. The difference between the left and right of the speed of the ultrasonic actuator 10B can be adjusted in response to a change in the state.

(Sixth Embodiment) FIG. 18 shows a sixth embodiment of the present invention.
FIG. 3 is a block diagram showing a drive circuit 70 of the vibration actuator drive device according to the embodiment. The oscillator 71 includes the vibrator 1
A drive signal of an AC voltage having a frequency corresponding to each of the longitudinal vibration L1 and the bending vibration B4 is generated. The output of the oscillator 71 is branched and one output is connected to the phase shifter 72.
And the phase is shifted by (π / 2)
After the phase voltage is set, the input region 13
a, 13c are input to the silver electrodes 15a, 15c. The other branched output is amplified by the amplifier 74 and then input as a B-phase voltage to the silver electrodes 15b and 15d of the input regions 13b and 13d.

The frequency control circuit 75 includes state values such as speed, frequency, and temperature from the detector 77 and the detection area 13p,
The pickup voltage from 13p 'is input. This frequency control circuit 75 lowers the frequency when the output of the detection areas 13p and 13p 'is smaller than the reference voltage set in advance, while the output of the detection areas 13p and 13p' This circuit controls the oscillator 71 so as to increase the frequency when it is large. Thus, the vibration amplitude of the vibrator 11 is maintained at a predetermined value.

The voltage regulator 76 is a circuit for adjusting the amplitude of the AC voltage based on the output from the detector 77 such as speed, frequency and temperature.
3,74. In this embodiment, the amplitude of the AC voltage is adjusted by changing the amplification factors of the amplifiers 73 and 74 to adjust the magnitude of the AC voltage.

FIG. 19 is a block diagram showing the voltage regulator 76 of FIG. 18 in detail. The voltage regulator 76 is a circuit that dynamically adjusts the amplification factors of the amplifiers 73 and 74 in a driving state based on a state value such as a relative speed with respect to the relative motion member 51, a frequency of an AC voltage, and an ambient temperature.

The detector 77 is a detector for detecting at least one of the above-mentioned state values such as speed, frequency and temperature. The writing device 78 is a device that writes the optimum voltage for the state value to the storage circuit 76a.

The voltage regulator 76 has a storage circuit 76a and a voltage regulator circuit 76b. In the storage circuit 76a,
In the adjustment stage before shipment, the writing device 78 writes a table indicating the relationship between the above-described parameters (state values) and the voltages corresponding thereto. Voltage adjustment circuit 76b
Is based on the values of the parameters detected by the detector 77 and the phase difference information from the phase shifter 72.
The optimum voltage is obtained from the table a. Then, the amplification factors of the amplifiers 73 and 74 are controlled so as to obtain the obtained optimum voltage.

FIG. 20 is a diagram showing the relationship between the voltage and the speed of the vibration actuator driving device according to the sixth embodiment of the present invention. The speed (right) graph shows the relationship when the phase difference is 90 °, and the speed (left) graph shows the relationship when the phase difference is −90 °. In FIG. 20, when the voltage is 40 [V], the speed is 240 [mm / s] when the phase difference is 90 °, and the speed is 280 [mm] when the phase difference is −90 °. / S], and the left-right difference is 40 [mm / s].

Therefore, in the sixth embodiment, the voltage regulator 7
6, the amplification factors of the amplifiers 73 and 74 are adjusted so that the voltage at the time of driving with a phase difference of −90 ° becomes 34 [V]. For this reason, when the phase difference is 90 °, the voltage is 40 [V], and when the phase difference is −90 °,
The voltage is automatically set to 34 [V], and the difference between the left and right speeds can be reduced to zero.

According to the sixth embodiment, the optimum amplification factor is calculated based on the value of the parameter detected by the detector 77, and the drive voltage is controlled. The difference between the left and right of the speed of the ultrasonic actuator 10B can be adjusted with respect to the change.

(Modifications) Various modifications and changes are possible without being limited to the embodiments described above, and they are also within the equivalent scope of the present invention. (1) The ultrasonic actuators 10, 1 of the above embodiment
In OB, an ultrasonic actuator using longitudinal primary vibration and bending quaternary vibration has been described as an example, but two-phase AC including actuators using generalized longitudinal n-order vibration and bending m-order vibration is used. Regarding the ultrasonic actuator driven by applying a voltage, it is possible to adjust the left-right difference in speed by using the same method.

(2) In the above-described embodiment, an example has been described in which the left and right speed difference is adjusted, but the left and right speed difference may be set arbitrarily. For example, it can be used for applications in which it moves strongly and slowly on the outward path, and has no load on the return path, so that it returns at high speed.

(3) The fourth to sixth embodiments can be similarly applied to drive control of the ultrasonic actuator 1 of the third embodiment. (4) In the fourth to sixth embodiments, as in the first embodiment, the difference between the left and right speeds of the ultrasonic actuator 10B may be corrected by performing adjustment at the time of adjustment work before shipping.

[0103]

As described above in detail, according to the present invention, the velocity in the moving direction of the ultrasonic actuator is adjusted by adjusting the parameters (phase difference, frequency, voltage) of the two-phase AC voltage waveform. Can be set. By adjusting the difference between the left and right speeds, it is possible to absorb various asymmetries that occur in manufacturing, and as a result, it is possible to improve the yield rate of the vibration actuator.

[Brief description of the drawings]

FIG. 1 is a view showing a first embodiment of a vibration actuator driving device according to the present invention, wherein FIG. 1 (A) is a perspective view showing an ultrasonic actuator 10 alone, and FIG. 1 (B) is an ultrasonic actuator. FIG.

FIG. 2 is a block diagram showing a driving circuit 20 of the vibration actuator driving device according to the first embodiment of the present invention.

FIG. 3 is a diagram showing a relationship between a phase difference and a speed of the vibration actuator driving device according to the first embodiment of the present invention.

FIG. 4 is a block diagram showing a drive circuit 20-2 of a vibration actuator drive device according to a second embodiment of the present invention.

FIG. 5 is a longitudinal sectional view showing a structure of a third embodiment of the vibration actuator driving device according to the present invention.

FIG. 6 is a block diagram showing a driving circuit 40 of a vibration actuator driving device according to a third embodiment of the present invention.

7 (a) is a view of the vibrator made of the two semi-cylindrical elastic bodies shown in FIG. 5 as viewed from the bottom direction, and FIG. 7 (b) is shown in FIG. It is the figure which looked at the oscillator from the side.

FIG. 8 is a sectional view showing a configuration of an ultrasonic actuator 10B according to a fourth embodiment of the present invention.

FIG. 9 is a perspective view showing the ultrasonic actuator 10B in a partially transparent state.

FIG. 10 is an explanatory diagram showing a longitudinal vibration L1 and a bending vibration B4 generated in the vibrator 11.

FIG. 11 is a block diagram showing a vibration actuator driving device according to a fourth embodiment of the present invention.

FIG. 12 is an explanatory diagram showing a detection position of a driving current of a vibration actuator driving device according to a fourth embodiment.

FIG. 13 is a circuit diagram showing a current detection circuit when a point A in FIG. 12 is a current detection point.

FIG. 14 is a timing chart illustrating the operation of the vibration actuator driving device according to the present embodiment.

FIG. 15 is a block diagram showing a driving circuit of a vibration actuator driving device according to a fifth embodiment of the present invention.

FIG. 16 is a block diagram showing a shift amount adjuster 66 of FIG. 15 in detail.

FIG. 17 is a diagram showing a relationship between a driving frequency and a speed of a vibration actuator driving device according to a fifth embodiment of the present invention.

FIG. 18 is a block diagram showing a driving circuit 70 of a vibration actuator driving device according to a sixth embodiment of the present invention.

FIG. 19 is a block diagram showing the voltage regulator 76 of FIG. 18 in detail.

FIG. 20 is a diagram showing a relationship between voltage and speed of a vibration actuator driving device according to a sixth embodiment of the present invention.

[Explanation of symbols]

 10, 10B Ultrasonic actuator 11 Vibrator 12 Elastic body 12a, 12b Driving force take-out part 13a, 13c, 13b, 13d Driving piezoelectric element 13p, 13p 'Vibration monitoring piezoelectric element 20 Drive circuit 21 Oscillator 22 Phase shifter 23, Reference Signs List 24 amplifier 25 control circuit 26 phase difference adjustment circuit 66 shift amount adjuster 76 voltage adjuster 114 drive circuit 116 power supply circuit 118 current detection circuit 120 analog / digital converter (A / D converter) 122 processing circuit 124 digital / analog converter ( D / A converter) 126 Voltage controlled oscillator 128 Divider 130 Direction switching circuit

Claims (17)

[Claims] An electromechanical transducer and a driving force extracting portion for extracting a driving force obtained by vibration generated by the electromechanical converting device, wherein the driving force comes into contact with the driving force extracting portion by the driving force. A vibration actuator that generates relative motion in at least two directions with a relative motion member; and a drive circuit that applies at least two-phase AC voltage to the electromechanical transducer to generate a plurality of vibration modes in harmony. A waveform adjustment circuit that adjusts a waveform of the AC voltage to match or vary a difference in drive speed depending on a moving direction when the vibration actuator moves in the first or second direction to set a desired state. And a vibration actuator driving device. 2. The vibration actuator driving device according to claim 1, wherein the waveform adjustment circuit adjusts a value of a parameter of the waveform in advance so that the vibration actuator moves in the first or second direction. A speed difference according to a moving direction of the vibration actuator. 3. The vibration actuator driving device according to claim 1, wherein at least one of an ambient temperature, a frequency of the AC voltage, and a relative speed with respect to a relative motion member that performs relative motion with the vibration actuator. A detector that detects a state value that includes a parameter value that changes a parameter value of the waveform of the AC voltage; and the waveform adjustment circuit includes an optimal parameter for the state value. A storage circuit for storing a value, a parameter change for obtaining an optimum parameter value from the storage circuit based on a detection result of the detector, and changing a parameter value of the parameter variable device to the optimum parameter value. A vibration actuator driving device, comprising: a circuit; 4. The vibration actuator driving device according to claim 3, further comprising a writing device that writes an optimum parameter value for the state value into the storage circuit. 5. The vibration actuator driving device according to claim 1, wherein the waveform adjustment circuit is a phase difference adjustment circuit that adjusts a phase difference between the two-phase AC voltages. . 6. The vibration actuator driving device according to claim 5, wherein the phase difference adjustment circuit adjusts a phase difference in advance to move the vibration actuator in the first or second direction. A vibration actuator driving device, wherein speed differences according to directions are made to match or differ. 7. The vibration actuator driving device according to claim 6, wherein at least one of an ambient temperature, a frequency of the AC voltage, and a relative speed with respect to a relative motion member that performs relative motion with the vibration actuator. The drive circuit includes a phase shifter that changes a phase of the AC voltage, and the phase difference adjustment circuit stores an optimal phase difference with respect to the state value. A storage circuit, based on a detection result of the detector, obtains an optimal phase difference from the storage circuit, and includes a phase difference changing circuit that changes the phase difference of the phase shifter to the optimal phase difference. Characteristic vibration actuator driving device. 8. The vibration actuator driving device according to claim 7, further comprising a writing device that writes an optimal phase difference with respect to the state value to the storage circuit. 9. The vibration actuator driving device according to claim 1, wherein the waveform adjustment circuit is a frequency adjustment circuit that adjusts a frequency of the two-phase AC voltage. 10. The vibration actuator driving device according to claim 9, wherein the frequency adjustment circuit adjusts a shift amount from an anti-resonance frequency of the vibrator including the vibrator and the electromechanical transducer. Characteristic vibration actuator driving device. 11. The vibration actuator driving device according to claim 10, wherein the frequency adjustment circuit adjusts a frequency shift amount in advance so that the vibration actuator moves in the first or second direction. A vibration actuator driving device, wherein a speed difference according to a moving direction is made equal or different. 12. The vibration actuator driving device according to claim 10, wherein at least one of an ambient temperature, a frequency of the AC voltage, and a relative speed with respect to a relative motion member that performs relative motion with the vibration actuator. A drive for oscillating the AC voltage at a predetermined frequency; and a frequency adjustment circuit for storing an optimal frequency shift amount with respect to the state value. And a frequency shift amount changing circuit that calculates an optimum frequency shift amount from the storage circuit based on the detection result of the detector and changes the frequency shift amount of the oscillator to the optimum frequency shift amount. A vibration actuator driving device comprising: 13. The vibration actuator driving device according to claim 12, further comprising a writing device that writes an optimum frequency shift amount with respect to the state value to the storage circuit. 14. The vibration actuator driving device according to claim 1, wherein the waveform adjustment circuit is a voltage adjustment circuit that adjusts the voltage of the two-phase AC voltage. 15. The vibration actuator driving device according to claim 14, wherein the voltage adjustment circuit adjusts a voltage in advance,
A vibration actuator driving device, wherein the speed difference according to the moving direction when the vibration actuator moves in the first or second direction is made to match or different. 16. The vibration actuator driving device according to claim 14, wherein at least one of an ambient temperature, a frequency of the AC voltage, and a relative speed with respect to a relative motion member that performs relative motion with the vibration actuator. A driving circuit including an amplifier for amplifying the voltage of the AC voltage at a predetermined amplification factor; and a voltage adjusting circuit configured to detect an optimum voltage for the state value. A storage circuit for storing, and an amplification factor changing circuit for obtaining an optimum voltage from the storage circuit based on a detection result of the detector and changing an amplification factor of the amplification so as to be the optimum voltage. A vibration actuator driving device characterized by the above-mentioned. 17. The vibration actuator driving device according to claim 16, further comprising: a writing device that writes an optimum amplification factor for the state value into the storage circuit.