CN1929283A - Drive control method for a piezoelectric actuator, drive control apparatus for a piezoelectric actuator, and electronic device - Google Patents

Abstract

The piezoelectric actuator drive control device has a controller, and executes an initialization process including an optimum phase difference acquisition process P 1 and a phase difference inversion detection process P 4 at a predetermined frequency. As a result, the optimum phase difference is updated each time the optimum phase difference acquisition process P 1 runs to account for wear or temperature change from continuous operation. Furthermore, even if the phase difference between the drive signal and detection signal inverts during a drive frequency sweep due to variation in the vibration characteristic of the piezoelectric actuator, the phase difference inversion frequency and clamping frequency are reset each time the phase difference inversion detection process (P4) is executed, thus preventing phase difference feedback control errors. Appropriate drive control based on the optimum phase difference can therefore be provided because the suitability and stability of the optimum phase difference are assured.

Description

Drive controlling method, driving control device and the electronic equipment of piezo-activator

Technical field

The present invention relates to drive controlling method, piezoelectric actuator drive control device and the electronic equipment of piezo-activator.

Background technology

Because piezoelectric element is good at aspects such as efficient that converts electrical energy into mechanical energy and responses, therefore developed the piezo-activator (supersonic motor) that is provided with vibrating body and the transfer of vibration of this vibrating body is driven to driven members such as rotors in recent years with piezoelectric element.The utilization of piezo-activator will expand in the various electronic equipments such as camera, printer, electronic watch and toy from now on.

Here, known have a kind of mode of resonance piezo-activator that utilizes the resonance of piezoelectric transducer, in this piezo-activator, need make the drive signal of supplying with piezoelectric element and keep constant substantially with the value that is suitable for driving, with the vibrational state of realizing being scheduled to by the phase difference of the detection signal that vibrational state obtained of piezoelectric transducer.That is, realize the optimum phase difference of predetermined driving condition, and carry out the drive controlling of piezo-activator according to this optimum phase difference by regulation.

In order to drive this piezo-activator expeditiously, the frequency of the drive signal of supplying with piezoelectric element is positioned near the resonance point of vibrating body, but because the resonance point of vibrating body changes because of influences such as ambient temperature and loads, therefore known to have frequency (driving frequency) by the change drive signal to make phase difference be the phase difference FEEDBACK CONTROL (with reference to patent documentation 1 and patent documentation 2) of optimum phase difference.Promptly in the driving process of piezo-activator, driving frequency is uprised or step-down with respect to the target phase extent according to phase difference.

[patent documentation 1]: No. 2506895 communique of Japan's special permission

[patent documentation 2]: Japanese kokai publication sho 64-8875 communique

But, realize the optimum phase difference of predetermined driving condition, owing to the individual difference that the driven member of the vibrating body in the piezo-activator is exerted pressure has deviation, and along with wearing and tearing between vibrating body and the driven member etc. through the time variation and changing.Optimum phase difference is the index of the drive controlling of piezo-activator, changes by changing this optimum phase official post torque, thereby is difficult to realize desired driving efficient.That is, the optimum phase difference that is suitable for predetermined driving condition not necessarily keeps constant.The variation of this optimum phase difference is caused by the variation of resonance point, therefore especially in utilizing the piezo-activator of resonance, even the little deviation of optimum phase difference and appropriate value also can cause driving the remarkable reduction of efficient owing to the minor shifts of resonance point causes.

In addition, in aforesaid phase difference FEEDBACK CONTROL, make driving frequency follow phase place extent with respect to the target phase difference of the phase difference of drive signal and detection signal, but the situation that has the evaluation counter-rotating of phase difference size owing to driving condition, this moment, driving frequency was to changing in the opposite direction with suitable side, caused the drive controlling instability.

That is, as shown in figure 38, suppose and to realize desired vibration characteristics by optimal drive state G during to predetermined direction turntable driving frequency, to have the rollback point Pt of the target phase difference θ that reaches optimal drive state G once more with preset width.At this moment, driving frequency follow direction according to the phase place extent with respect to target phase difference reverses (to this in the front and back of this rollback point Pt, hereinafter referred to as the counter-rotating of phase difference, reversal development etc.), with the scope B of the driving scope A adjacency that comprises optimal drive state G and be used for driving, phase difference variable big (+) with respect to target phase difference θ, therefore, driving frequency promptly changes to the direction that rises to the opposite direction of suitable direction, makes phase difference near target phase difference θ.Its result causes driving condition to move to scope C from scope B, in this scope C, gradient with respect to the phase difference of target phase difference θ is identical with the scope of driving A, driving frequency changes to the direction identical with the scope of driving A, therefore driving condition is not got back to driving scope A, and piezo-activator drives under unsure state with lower driving efficient.The requirement distance of the vibration characteristics that the driving frequency of this scope C and scope B and phase difference and realization are desired is far.

In addition, driving condition moves to scope B from driving scope A, be because in the driving process of piezo-activator, the following of driving frequency of carrying out continuously by phase difference feedback causes, if fixed drive frequency is carried out drive controlling, then not too can be subjected to the influence of phase difference counter-rotating, still, in the structure of fixed drive frequency, can't be corresponding to Yin Wendu or load variations and driving frequency is regulated in the change of the resonance point that causes.For situation about in the bigger environment of variations in temperature, driving, and owing to produce more high-power or, still need suitably to adjust driving frequency up and down by phase difference feedback etc. owing to the situation that needs Continuous Drive to generate heat.

But, feed back the variable control that driving frequency is carried out by phase difference, thus can be corresponding to the variation of temperature or load, but as mentioned above, owing to the counter-rotating of phase difference evaluation causes the driving frequency controlling party to unusually, make the driving condition instability, become problem on the contrary.

Here, as one of major reason that in phase difference, produces reversal development, consider the rigging error of vibrating body.That is, consider following reason: as the structure of vibrating body, have structure that makes a plurality of piezoelectric element clamping stiffeners and fit etc., be offset owing to the applying error causes the phase place of each piezoelectric element, and this phase deviation accumulates.

In addition, as patent documentation 2, existing is not that two drive signals that phase place differs from one another are offered piezoelectric element, but generate the situation that drive signal is come the drive pressure electric device with the frequency between the resonance point of the resonance point of extensional vibration and flexural vibrations, but under this situation, because the synthetic of the phase place of the phase place of extensional vibration and flexural vibrations also is enough to cause phase difference to reverse.

Summary of the invention

In view of the above problems, the object of the invention be to provide a kind of can be according to the variation of the drive condition that is suitable for predetermined driving condition and suitably and stably carry out drive controlling method, piezoelectric actuator drive control device and the electronic equipment of the piezo-activator of drive controlling.

The present invention is a kind of drive controlling method of piezo-activator, the vibrating body that provides drive signal to vibrate by to piezoelectric element is provided this piezo-activator, and with this transfer of vibration to driven member, can detect simultaneously the vibrational state of described vibrating body, it is characterized in that, this method comprises: the initial setting process, this process has: the phase difference of detection signal of described drive signal and the described detected vibrational state of expression is implemented the frequency scanning of described drive signal, is that the optimum phase difference of optimum phase difference is obtained process to obtain the phase difference of realizing predetermined driving condition; And the phase difference that detects described drive signal and described detection signal, in the preset range that comprises the frequency that realizes described predetermined driving condition, implement simultaneously the frequency scanning of described drive signal, the phase difference of the phase difference reversal frequency when detecting described phase difference this moment and the reaching described optimum phase difference once more testing process of reversing towards predetermined direction; And driving process, this process limits the frequency of described drive signal, to avoid it to reach the clamper frequency of in the value of the described predetermined driving condition side of described phase difference reversal frequency, setting, and in the phase difference that detects described drive signal and described detection signal, according to described phase difference with respect to described optimum phase extent, make the frequency gets higher or the step-down of described drive signal, thereby make the frequency of described drive signal follow described phase difference; By carrying out described initial setting process, upgrade described optimum phase difference and described phase difference reversal frequency respectively with predetermined frequency.

In addition, the present invention is a kind of piezoelectric actuator drive control device, the vibrating body that provides drive signal to vibrate by to piezoelectric element is provided this device, and with this transfer of vibration to driven member, can detect simultaneously the vibrational state of described vibrating body, it is characterized in that this device comprises: the initial setting unit, it has: the phase difference detection unit that detects the described drive signal and the phase difference of the detection signal of the described detected vibrational state of expression; Implement the frequency scanning of described drive signal, obtaining the phase difference of realizing predetermined driving condition according to the detection of the described phase difference that is undertaken by described phase difference detection unit is that the optimum phase difference of optimum phase difference is obtained the unit; And the phase difference that detects described drive signal and described detection signal, in the preset range that comprises the frequency that realizes described predetermined driving condition, implement simultaneously the frequency scanning of described drive signal, the phase difference of the phase difference reversal frequency when detecting described phase difference this moment and the reaching described optimum phase difference once more detecting unit that reverses towards predetermined direction; Control unit, it sets the frequency of described drive signal according to described optimum phase difference; And the frequency control unit, it upgrades described optimum phase difference and described phase difference reversal frequency respectively by carrying out the processing of described initial setting unit with predetermined frequency; Described control unit has the clamper unit, it limits the frequency of described drive signal, to avoid it to reach the clamper frequency of in the value of the described predetermined driving condition side of described phase difference reversal frequency, setting, described control unit is implemented by the restriction of described clamper unit to the frequency of described drive signal, and when detecting described phase difference by described phase difference detection unit, according to described phase difference with respect to described optimum phase extent, make the frequency gets higher or the step-down of described drive signal, thereby make the frequency of described drive signal follow described phase difference.

According to these inventions, even at the optimum phase difference of realizing predetermined driving condition, because the pressurized conditions of caused vibrating body of friction and driven member changes, perhaps under the former thereby situation about changing such as the caused variations in temperature of Continuous Drive of piezo-activator, also can in initial setting, carry out obtaining of optimum phase difference with predetermined frequency, upgrade optimum phase difference and proofread and correct and be suitable optimum phase difference, thereby can be according to this optimum phase difference, implement suitable drive controlling, by the required suitable actuating force (torque) of the driving of driven member, realize required driving efficient.

In addition, predetermined frequency for example be every a few minutes～waited in several hours certain during, perhaps wait and stipulate according to the number of starts of piezo-activator, the number of times of carrying out predetermined action.

In addition, also implementing the phase difference counter-rotating in initial setting detects.That is,, detect the frequency when the phase difference counter-rotating takes place, thereby the phase difference reversal frequency is also upgraded along with the renewal of optimum phase difference in initial setting, having carried out the optimum phase difference of initialization (renewal).

Particularly, in phase difference counter-rotating testing process, detect the phase difference of drive signal and detection signal and carry out driving frequency scanning, at this moment, reach once more at phase difference under the situation of optimum phase difference, detected phase contrast reversal frequency is as the frequency that produces the phase difference counter-rotating.In addition, in the drive controlling behind initial setting, in order to prevent the counter-rotating of phase difference with respect to the optimum phase extent, the restriction driving frequency reaches the clamper frequency of setting according to the phase difference reversal frequency with the frequency of avoiding drive signal, makes the frequency of drive signal follow the control of phase difference simultaneously.Thereby can prevent the abnormality processing of the driving frequency inverse change that causes owing to the related reversal development of the evaluation of phase difference, can stably implement drive controlling.In addition, the phase difference reversal frequency can be identical with the clamper frequency.

As mentioned above, since wearing and tearing wait through the time change or variations in temperature etc. is former thereby situation that resonance point and optimum phase difference are changed, and, can tackle well as under the vibration characteristics of the piezo-activator situation that phase difference reverses when the frequency scanning sometimes.Therefore, no matter the driving time of the environment for use of piezo-activator or piezo-activator etc. how, can both further enlarge the scope of application (can long-time continuous drive) of piezo-activator, improve reliability and also reduce cost.

Here, in such the present invention, the phase place of detection signal to the vibrational state of expression vibrating body, compare with the phase place of drive signal, because to carry out with the optimum phase difference be the phase difference FEEDBACK CONTROL of target, so can be desired value with the driving control from view of profit that is expressed as the driving amount (rotating speed etc.) of the current value of piezo-activator or driven member.Thereby can control the speed of driven member.

In the drive controlling method of piezo-activator of the present invention, preferably, described piezo-activator is loaded into and has timing portion and show in the time set of clocking information display part of the clocking information by the timing of described timing portion, to drive described clocking information display part, described optimum phase difference is obtained process and is had the amount of movement recuperation, position when this process makes the position of the described driven member that moves during implementing this optimum phase difference to obtain process turn back to this optimum phase difference to obtain process and begin, in described driving process, according to the time during the described initial setting process of enforcement, according to the command value of sending from described timing portion, control the amount of movement of this driven member.

According to the present invention, in time sets such as wrist-watch, in the piezo-activators as driven member such as gear that are assembled with the interlock of clocking information display part such as pointer, owing to can eliminate the amount of movement of the driven member in the initial setting process, thereby can eliminate owing to implementing pointer operation errors and the wrist-watch fault that the initial setting process causes.

In the drive controlling method of piezo-activator of the present invention, preferably, in described phase difference counter-rotating testing process, the value from described clamper frequency to described phase difference reversal frequency is stored in the memory cell.

In addition, in piezoelectric actuator drive control device of the present invention, preferably, described control unit has the memory cell of storing in advance from described clamper frequency to the value of described phase difference reversal frequency.

According to these inventions, by the value of storage, do not need when each phase difference feeds back, to set the clamper frequency according to the phase difference reversal frequency from the clamper frequency to the phase difference reversal frequency, can simplified structure.

In the drive controlling method of piezo-activator of the present invention, preferably, the driving direction of described driven member can switch in positive direction with in the other direction, and described initial setting process is carried out when the driving direction of described driven member is switched.

In addition, in piezoelectric actuator drive control device of the present invention, preferably, the driving direction of described driven member can switch in positive direction with in the other direction, and described initial setting unit uses when described vibrational state switches.

According to these inventions, when the driving direction of driven member is switched, implement initial setting once more, upgrade optimum phase difference and phase difference reversal frequency, even therefore under the situation of the vibrational state characteristic different (asymmetric) of the vibrating member when positive direction drives driven member with opposite direction, the appropriateness of drive controlling and stability are not suffered damage.

In piezoelectric actuator drive control device of the present invention, preferably, described vibrating body vibrates with a plurality of vibration modes, and described drive signal is single-phase.

According to the present invention, by supplying with single-phase drive signal,, therefore compare with the situation of using heterogeneous drive signal with a plurality of vibration mode drive pressure electric devices, can simplified structure.

In piezoelectric actuator drive control device of the present invention, preferably, it is rectangular-shaped that described vibrating body forms general plane, and described a plurality of vibration modes are along the flexible extensional vibration of the length direction of described vibrating body with respect to the mixed mode of the flexural vibrations of described length direction bending.

According to the present invention, the drive signal of the frequency between the resonance point by supplying with extensional vibration to vibrating body and the resonance point of flexural vibrations, the elliptic motion of the part of vibrating body can be realized, thereby driven members such as rotor can be driven expeditiously with simple structure.

Here, according to the mixed mode of the extensional vibration of so single-phase drive signal of supply and flexural vibrations as can be known, because the phase place of extensional vibration and the phase place of flexural vibrations is synthetic, and be easy to take place the counter-rotating of the phase difference of drive signal and detection signal, therefore, by carrying out the detection of aforesaid phase difference reversal frequency, and according to based on the clamper processing of this phase difference reversal frequency or clamper frequency etc., the effect of implementing stabilized driving is just more obvious.

Electronic equipment of the present invention is characterised in that, the driven member and the described piezoelectric actuator drive control device that have piezo-activator, driven by this piezo-activator.

According to the present invention, owing to have described piezoelectric actuator drive control device, thus can enjoy aforesaid effect and effect.

Promptly, can according to wearing and tearing, load variations etc. through the time change and variations in temperature, implement suitable stable drive controlling, and be applicable in the violent environment such as outdoor of variations in temperature, use or causing various electronic equipments load variations, that be easy to generate heat owing to have high input power or Continuous Drive owing to carrying posture.As such electronic equipment, for example can enumerate mobile phone, portable information terminal, touchable toy, camera, printer etc.

Electronic equipment of the present invention is preferably has timing portion and the expression wrist-watch by the clocking information display part of the clocking information of described timing portion timing.

According to the present invention, by described piezo-activator, can drive gear that constitutes timing portion and the indicating device that constitutes the clocking information display part etc. exactly, can improve reliability.

And, if when driving, the moment indication mechanism of minute, second etc., then can realize pointer running accurately by piezo-activator, even and under the situation of generating heat owing to Continuous Drive, also can prevent the drive controlling instability.

In addition, except moment indication mechanism, piezo-activator is carried out driving intermittence, also can be used for the timing portion or the clocking information display part of calendar informations such as day, the moon, week by changing according to calendar.

In addition, can realize the advantage of piezo-activator, that is: not be subjected to effect of magnetic influence, can utilize small increment to realize higher response, help lightening miniaturization, can realize high torque (HT) etc.

In addition, described piezoelectric actuator drive control device can realize with hardware, also can use control program to realize.

In this control program, can make the function of the computer performance control unit of the described driving control device of packing into and phase difference detection unit etc.

If constitute like this, then can obtain the action effect same with described driving control device.

Here, this control program can be by computers of packing into such as networks, and the storage medium of embodied on computer readable that also can be by having stored this program is packed into.

If in pack into the wrist-watch or the portable equipments such as control program that will provide by means of communication such as such storage medium or internet, then can only obtain aforesaid action effect, and also can be chosen in when dispatching from the factory or the desired control program of user is packed into by reprogramming.At this moment since can be only by reprogramming and different various wrist-watches or the portable equipments of production control mode, thereby can realize generalization of parts etc., and the manufacturing cost when reducing product significantly and launching.

According to the present invention, can implement suitable drive controlling according to the variation of the drive conditions such as phase difference that are suitable for predetermined driving condition, and when making driving frequency follow phase difference, even when temperature or load variations, also can stably implement drive controlling.

Description of drawings

Fig. 1 is the outside drawing of the wrist-watch of first embodiment of the invention.

Fig. 2 is the stereogram of the piezo-activator unit of first execution mode.

Fig. 3 is the vertical view of the piezo-activator unit of first execution mode.

Fig. 4 is the block diagram of structure of the piezoelectric actuator drive control device of expression first execution mode.

Fig. 5 (A) is the vibrating body at first execution mode, represents the curve chart of the relation of driving frequency and impedance, (B) is the vibrating body at first execution mode, the curve chart of the relationship of amplitude of expression driving frequency and extensional vibration and flexural vibrations.

Fig. 6 is the block diagram of primary structure of the controller of the piezoelectric actuator drive control device of expression with first execution mode.

Fig. 7 is the flow chart that the optimum phase difference of the piezoelectric actuator drive control device of expression first execution mode is obtained process.

Fig. 8 is the flow chart of driving process of the piezoelectric actuator drive control device of expression first execution mode.

Fig. 9 is the figure of variation of drive characteristic of the piezo-activator of expression first execution mode.

Figure 10 is the block diagram of structure of the piezoelectric actuator drive control device of expression second embodiment of the invention.

Figure 11 is the block diagram of structure of the driving control device of expression third embodiment of the invention.

Figure 12 is the flow chart that the optimum phase difference of the piezoelectric actuator drive control device of expression third embodiment of the invention is obtained process.

Figure 13 is the block diagram of structure of the driving control device of expression four embodiment of the invention.

Figure 14 is the block diagram of structure of the piezoelectric actuator drive control device of expression fifth embodiment of the invention.

Figure 15 is the block diagram of primary structure of the controller of the piezoelectric actuator drive control device of expression with the 5th execution mode.

Figure 16 is the vibrating body at the 5th execution mode, the curve chart of the rotating speed of phase difference, rotor during the frequency scanning of expression drive signal and the variation of current value.

Figure 17 be Figure 16 curve chart want portion's enlarged drawing.

Figure 18 is the figure of the memory cell form data of storing of expression the 5th execution mode.

Figure 19 is the flow chart of drive controlling of initialize mode of the piezo-activator of expression the 5th execution mode.

Figure 20 is the flow chart of drive controlling of drive pattern of the piezo-activator of expression the 5th execution mode.

Figure 21 is the curve chart of drive characteristic of the piezo-activator of expression the 5th execution mode.

Figure 22 is the figure that compares with Figure 21, is illustrated in the drive characteristic when not implementing the driving frequency restriction in the piezo-activator of the 5th execution mode.

Figure 23 is the block diagram of structure of the piezoelectric actuator drive control device of expression sixth embodiment of the invention.

Figure 24 is the block diagram of structure of the driving control device of expression seventh embodiment of the invention.

Figure 25 is the block diagram of structure of the driving control device of expression eighth embodiment of the invention.

Figure 26 is the block diagram of structure of the piezoelectric actuator drive control device of expression ninth embodiment of the invention.

Figure 27 is the block diagram of primary structure of the controller of the piezoelectric actuator drive control device of expression with the 9th execution mode.

Figure 28 is the flow chart that the optimum phase difference of the piezoelectric actuator drive control device of expression the 9th execution mode is obtained process and phase difference counter-rotating testing process.

Figure 29 is the flow chart of driving process of the piezoelectric actuator drive control device of expression the 9th execution mode.

Figure 30 is the flow chart that the optimum phase difference of the variation of expression the 9th execution mode is obtained process and phase difference counter-rotating testing process.

Figure 31 is the flow chart that the optimum phase difference of another variation of expression the 9th execution mode is obtained process and phase difference counter-rotating testing process.

Figure 32 is the block diagram of structure of the piezoelectric actuator drive control device of expression tenth embodiment of the invention.

Figure 33 is the block diagram of structure of the driving control device of expression eleventh embodiment of the invention.

Figure 34 is the flow chart that the optimum phase difference of the piezoelectric actuator drive control device of expression the 11 execution mode is obtained process.

Figure 35 is the block diagram of structure of the driving control device of expression twelveth embodiment of the invention.

Figure 36 is the flow chart of the driving process of expression the present invention first variation.

Figure 37 is the flow chart of the driving process of expression the present invention second variation.

The curve chart of the rotating speed (driving amount) of phase difference, rotor when Figure 38 is the frequency scanning of expression drive signal and the variation of current value.

Embodiment

[first execution mode]

With reference to the accompanying drawings embodiments of the present invention are described.

[1. overall structure]

Fig. 1 is the vertical view of the electronic watch 1 of expression present embodiment.Electronic watch 1 is the wrist-watch (watch) as time set, this electronic watch 1 has: as the parts 2 of timing portion, the dial plate 3 as the clocking information display part that is used to show the common moment, hour hands 4, minute hand 5, second hand 6, have in addition: the timing second pin 7A of expression timing time, branch timing pin 7B.On the housing of electronic watch 1, be provided with knob 8, and clip action button 9A, 9B that knob 8 is provided with timer.

Hour hands 4, minute hand 5 and second hand 6 are identical with common quartz watch, drive by the circuit substrate that is assembled with quartz vibrator, the stepping motor with coil, stator and rotor, drive train and battery.

[the 2. driving mechanism of second timing pin]

Driving second driving mechanism of timing pin 7A comprises: piezo-activator (supersonic motor) 20; Be rotated the rotor 30 as driven member of driving by this piezo-activator 20; And the deceleration train 40 that makes the rotational delay of this rotor 30 and transmit.

Deceleration train 40 comprises: with rotor 30 arranged coaxial and with the gear 41 of rotor 30 one rotations; And with 41 engagements of this gear and be fixed in gear 42 on second rotating shaft of timing pin 7A.

In addition, piezo-activator 20, rotor 30 and gear 41 shown in Fig. 2,3, become the part of piezo-activator unit 10.

[the 3. structure of piezo-activator unit]

Piezo-activator unit 10 comprises: be fixed in the supporting bracket 11 on the base plate etc. of electronic watch 1; Be fixed in the piezo-activator 20 on the supporting bracket 11; Rotation freely is installed on rotor 30 and the gear 41 on the supporting bracket 11.

In addition, the rotation of gear 41 can detect by the rotation sensor 15 that is disposed at gear 41 tops.

It is porose 12 that supporting bracket 11 forms for weight reduction, and be fixed on base plate etc. by fixed parts such as screw 13.In addition, on supporting bracket 11, be fixed with the spacer portion 14 that piezo-activator 20 has been installed.

[the 4. structure of piezo-activator]

Piezo-activator 20 has by the tabular stiffener of essentially rectangular 21 and is adhered to the vibrating body 20A that the piezoelectric element 22 on the two sides of stiffener 21 constitutes shown in Fig. 2,3.

Substantial middle at the length direction of stiffener 21 is formed with towards two side-prominent arms 23, and these each arms 23 are fixed on the described spacer portion 14 by screw 24.In addition, the stiffener 21 with arm 23 is made of conductive metal, and arm 23 also can be as the electrode that applies drive signal to piezoelectric element 22.

In the end of length direction one side of stiffener 21, particularly be with rotor 30 opposed ends on, be formed with along the outstanding projection 25 of the length direction of stiffener 21 the side butt of projection 25 and rotor 30.This projection 25 is under the state of having set with the relative position of rotor 30, by the application of force unit application of force arbitrarily such as spring, make its outer peripheral face butt with predetermined force and rotor 30, by the suitable frictional force of effect between the side of projection 25 and rotor 30, can make the vibration of vibrating body 20A be passed to rotor 30 efficiently.

In addition, in the present embodiment, on the outer peripheral face of rotor 30, be formed with groove 31 (Fig. 2), projection 25 be set in the part of this groove 31.When dropping piezo-activator 20 is produced under the situation of impacting, can pass through these groove 31 channeling conducts, separate with the bearing surface of rotor 30 to avoid projection 25 as electronic watch 1.

It is tabular that piezoelectric element 22 forms essentially rectangular, and bonding with the essentially rectangular shape part on stiffener 21 two sides.On the two sides of piezoelectric element 22, form electrode by plating, sputter, evaporation etc.

In addition, on the face of stiffener 21 sides of piezoelectric element 22, on its whole, form an electrode,, be electrically connected (with reference to N among Fig. 4) with driving control device 50 (Fig. 4) by stiffener 21 and the arm 23 that contacts with this electrode.

In addition, on the face of piezoelectric element 22 face side, be formed with the electrode of cutting apart quinquepartite as shown in Figure 3.That is, the electrode of piezoelectric element 22 face side trisection roughly on the Width of piezoelectric element 22 forms drive electrode 221 by its central electrode.In addition, the electrode of drive electrode 221 both sides is roughly halved on the length direction of piezoelectric element 22, forms each other in right drive electrode 222 and drive electrode 223 on the diagonal of piezoelectric element.

These drive electrodes 221,222,223 are connected with driving control device 50 by lead etc. respectively and (with reference to P1 among Fig. 4～P3), and apply voltage between itself and stiffener 21 (N in reference to Fig. 4).In addition, the power supply of driving control device 50 is provided with three, is respectively applied between drive electrode 221 and the stiffener 21, between drive electrode 222 and the stiffener 21, apply voltage between drive electrode 223 and the stiffener 21.

In such electronic watch 1, supply with single-phase drive signal by driving control device 50 (Fig. 4) to piezo-activator 20, rotor 30 rotations are driven.

Here, according to making second timing pin 7A to predetermined positive direction rotation or to opposite spin, optionally use the drive electrode 222,223 that is arranged on the piezoelectric element 22,, rotor 30 is driven to the rotation of two directions according to the vibrational state of vibrating body 20A at this moment.

Promptly, at vibrating body 20A because positive direction state and when positive direction drives, with drive electrode 221 and drive electrode 222 as the object that applies voltage, according to the phase difference of the mixed mode of extensional vibration that vibrating body 20A is produced and flexural vibrations, make the projection 25 of vibrating body 20A draw the roughly elliptical orbit E (Fig. 3) that the center line with respect to the length direction of piezoelectric element 22 tilts.On the part of this track E, projection 25 pushing rotors 30, thus make rotor 30 positive directions rotations (direction of arrow among Fig. 3).

On the other hand, at vibrating body 20A because state and when opposite direction drives in the other direction, replace drive electrode 222 and with drive electrode 223 as the object that applies voltage, it is the line symmetry relation of axle that drive electrode 222 and drive electrode 223 have with the center line of the length direction of piezoelectric element 22, therefore, with respect to the crisscross generation of extensional vibration and the flexural vibrations that drive electrode 222 applied voltage condition substantial line symmetry.Thereby the track that makes the projection 25 of vibrating body 20A becomes and drive electrode 222 is applied the roughly elliptical orbit that the voltage condition substantial line tilts symmetrically, and rotor 30 opposite spins are driven.

By the rotation of such rotor 30, the gear 41 with rotor 30 one is also rotated, gear 42 rotates along with the rotation of gear 41, to positive direction or drive a second timing pin 7A in the other direction.

In addition, the detection signal (vibration signal) of the vibrational state of expression vibrating body 20A detects by the drive electrode 223 that does not apply drive signal when rotor 30 is just changeing, and detects by the drive electrode 222 that does not apply drive signal when rotor 30 counter-rotatings.

[the 5. structure of the drive unit of piezo-activator]

Below with reference to Fig. 4 the structure of the driving control device 50 of piezo-activator 20 is described.

Among Fig. 4, driving control device 50 comprises: voltage-controlled oscillator (VCO) 51; Pulse control circuit 52; Gate drivers 53; Power supply 54; Switching circuit 55; Band pass filter (BPF) 56; Signal amplifier (AMP) 57; Phase difference detection unit 60; And as the controller 65 of control unit.

Voltage-controlled oscillator 51 is the oscillators of frequency that can change the signal of output according to the voltage that is applied, and generates the drive signal of piezo-activator 20.

In addition, the resonance point of the extensional vibration of consideration vibrating body 20A and the resonance point of flexural vibrations etc., the frequency (driving frequency) of decision drive signal.

The driving frequency of Fig. 5 (A) expression vibrating body 20A and the relation of impedance, driving frequency and the amplitude of extensional vibration and the relationship of amplitude of flexural vibrations of Fig. 5 (B) expression vibrating body 20A.

Shown in Fig. 5 (A), two impedance phases and resonance point of amplitude maximum minimum for driving frequency appears, and the lower side of its medium frequency is the resonance point of extensional vibration, and a higher side is the resonance point of flexural vibrations.

That is, if drive vibrating body 20A between the crooked syntony frequency f r2 of vertical resonance frequency fr1 of extensional vibration and flexural vibrations, then can guarantee the amplitude of extensional vibration and flexural vibrations, the drive pressure electric actuator 20 expeditiously.In addition, by making vertical resonance frequency fr1 and crooked syntony frequency f r2 closer to each other, can set the bigger driving frequency of amplitude that makes extensional vibration and flexural vibrations.

Return Fig. 4, the drive signal that pulse control circuit 52 control is generated by voltage-controlled oscillator 51, it constitutes and comprises: generate the generative circuit 521 idle time that is used to idle time of controlling the switching timing of switching circuit 55 described later and suppressing perforation electric current; The direction of rotation of Switch Rotor 30 and export the positive and reverse return shifting circuit 522 and the current control circuit 523 of this instruction; And the current control circuit 524 that in the cycle of drive signal, inserts the duty ratio of regulation drive signal idle time.

Positive and reverse return shifting circuit 522 is according to control signal, and the command value of the direction of rotation of Switch Rotor 30 is exported to second grid driver 53B.Particularly, the command value that will correspond respectively to drive electrode 221,222 when the positive rotation of rotor 30 is to second grid driver 53B output, and the signal of selecting to correspond respectively to drive electrode 221,223 when the despining of rotor 30 is exported to second grid driver 53B.

Gate drivers 53 be according to from the drive signal of pulse control circuit 52 output to the conducting of switching circuit 55 by the drive circuit of controlling, have two in the present embodiment, i.e. first grid driver 53A and second grid driver 53B.

And the drive signal that is input to second grid driver 53B from pulse control circuit 52 becomes the signal with the drive signal counter-rotating that is input to first grid driver 53A via inverter (NOT circuit) IV.

Power supply 54 in the present embodiment, second source 542 by first power supply 541 in positive and negative when rotation that is used for rotor 30, when only being used for the positive rotation of rotor 30 and the 3rd power supply 543 when only being used for the despining of rotor 30 constitute, by these first, second, third power supplys 541,542,543, piezo-activator 20 is applied the voltage of the potential difference between power vd D and the VSS, the perhaps supply voltage of the potential difference between power vd D and the GND.

Switching circuit 55 comprises: the switch 551,552,555,557 that is made of P channel MOS-FET; With the switch 553,554,556,558 that constitutes by N-channel MOS-FET.These each switches 551～558 carry out conducting by control by control by the voltage that first grid driver 53A and second grid driver 53B impose on grid.

In addition, second grid driver 53B is connected with positive and reverse return shifting circuit 522, when the positive rotation of rotor 30, and only driving switch 552,553 (P1 among Fig. 4) and switch 555,556 (P2).

Promptly, when the positive rotation of rotor 30, the first grid driver 53A of driving switch 551,554, second grid driver 53B with driving switch 552,553 (P1) and switch 555,556 (P2), drive signal work with mutual counter-rotating, therefore, the switch 551,552 of identical P channel MOS-FET is under the situation of switch 551 conductings, and another switch 552 ends.In addition, the switch 551,555 of identical P channel MOS-FET formation too.

And similarly, the switch 553,554 of N-channel MOS-FET is under the situation of switch 553 conductings, and another switch 554 is by (switch 556,554 of N-channel MOS-FET too).

And the switch 551,554 that is connected in series is under the situation of side's conducting, and the opposing party ends.Similarly, the switch 552,553 that is connected in series, perhaps, also under the situation of side's conducting, the opposing party ends switch 555,556.

These switches 551～554 (perhaps switch 551,555,556,554) are by first grid driver 53A and second grid driver 53B and piezoelectric element 22 bridge joints, switching circuit by the pair of switches on the diagonal angle that is positioned at bridge 551,553 (perhaps switch 551,556) formation, with by another switching circuit that switch 552,554 (perhaps switch 555,554) is constituted, the conducting that hockets is by control.Thus, the predetermined supply voltage that is applied by power supply 54 is transformed to the square-wave voltage of alternation, applies sub-piezo-activator 20.Promptly, between drive electrode 221,222 and stiffener 21 (Fig. 2), piezoelectric element 22 is applied alternating voltage, make the rotation of rotor 30 positive directions by first power supply 541 and second source 542.

On the other hand, when the despining of rotor 30, second grid driver 53B place of switches 555,556 (P2) and driving switch 557,558 (P3), switch 551,552,553,554 (perhaps switch 551,557,558,554) and piezoelectric element 22 bridge joints, switching circuit by switch 551,553 (with switch 551,558) formation, with the switching circuit that is made of switch 554,552 (perhaps switch 554,557), the conducting that hockets is by control.Promptly, between drive electrode 221,223 and stiffener 21 (Fig. 2), piezoelectric element 22 is applied alternating voltage, make rotor 30 opposite spins by first power supply 541 and the 3rd power supply 543.

In addition, when the conducting of carrying out each switch 551～558 ends switching, if switch that is connected in series 551,554 and switch 552,553 (perhaps switch 555,556 and switch 557,558) conducting simultaneously then can be flow through perforation electric current.Because this perforation electric current can not be used for the driving work of piezo-activator 20, therefore cause the waste of consumed power, and become the reason that causes that switch element burns out etc.Therefore, in pulse control circuit 52, after a switch ends, in the process scheduled time (idle time) afterwards, make another switch conduction, thereby prevent perforation electric current.

Band pass filter (unimodal filter) the 56th according to the vibrational state of piezo-activator 20, only makes the detection signal that is included in the frequency of predetermined frequency range in the detected detection signal pass through, and makes the filter of the signal attenuation of other frequencies.

In addition, detection signal detects by a side (with reference to P2, P3 among Fig. 4) who does not supply with drive signal in the drive electrode 222,223 according to the forward or reverse of rotor 30.Here, detection signal with the current potential of arm 23 (N among Fig. 5) as reference signal, poor by with respect to the current potential of the drive electrode 222 of this reference signal, perhaps poor with respect to the current potential of the drive electrode 223 of reference signal, that is, the differential wave with respect to the drive electrode 222,223 of arm 23 detects.

Detection signal by band pass filter 56 is amplified by signal amplifier 57.

Phase difference detection unit 60 comprises: phase controller 61; Phase shifter 62; Phase comparator 63; And low pass filter (LPF) 64.

61 per two signal periods of phase controller, correspondingly, phase shifter 62 moved the phase place of predefined optimum phase difference, detection signal to phase shifter 62 output control signals.

63 pairs of phase comparators compare from the phase place of the detection signal of phase shifter 62 outputs with from the phase place of the drive signal of voltage-controlled oscillator 51 outputs, export its phase difference.Here, as mentioned above, phase shifter 62 only moves the phase place of detection signal with optimum phase difference, and the output of phase comparator 63 is approaching more zero, and then the phase place of detection signal is more near optimum phase difference.

Low pass filter 64 is that the signal of the following frequency of preset frequency is passed through, and makes the filter of the signal attenuation of the frequency more than the preset frequency, the function of performance integrating circuit.

According to above-mentioned phase difference detection unit 60, the phase place of the detection signal that moves by phase shifter 62 and the phase place of drive signal poor, promptly with the deviation (size) of optimum phase difference by low pass filter 64 to controller 65 outputs.

Controller 65 is to voltage-controlled oscillator 51 output voltage signals, with the deviation of elimination with the optimum phase difference of being imported.

Fig. 6 is the structure skeleton diagram of controller 65, and controller 65 comprises: make the frequency of drive signal follow the frequency control unit 651 of the phase difference of feedback by phase difference detection unit 60; The optimum phase difference that obtains the optimum phase difference of the predetermined driving condition of realization is obtained unit 652; Make the frequency control unit 653 of the frequency regularization that optimum phase difference obtains; And memory cell 654 waits each structure.

Here, optimum phase difference is obtained the obtaining of optimum phase difference of unit 652, carries out the Continuous Drive time rule that this frequency rises when making piezo-activator 20 startups by the operation by action button 9A (Fig. 1) with predetermined frequency by frequency control unit 653.Frequency in the present embodiment is one hour for the Continuous Drive time, and this time is stored in the memory cell 654.

[the 6. drive controlling of piezo-activator]

Describe below with reference to the effect of Fig. 7 and flow chart shown in Figure 8 the piezo-activator 20 by driving control device 50.

The controller 65 of driving control device 50 is carried out optimum phase difference shown in Figure 7 respectively and is obtained process P1 and driving process P2 shown in Figure 8.

[effect of 6-1. frequency control unit]

Controller 65 is confirmed as shown in Figure 7 from the elapsed time T of piezo-activator 20 starting beginnings by the timer function of frequency control unit 653, be i.e. the Continuous Drive time (step S11), implemented optimum phase difference with predetermined frequency and obtain process P1.Promptly, in the affirmation (step S11) of Continuous Drive time, when the elapsed time T from piezo-activator 20 starting the time reaches Continuous Drive time N the memory cell 654 that is stored in controller 65 (being), implement optimum phase difference and obtain process P1, and (deny) to change driving process P2 shown in Figure 8 over to when not reaching.

In addition, elapsed time T is initialized as " 0 " when piezo-activator 20 startings.

[the 6-2. optimum phase difference is obtained process]

Obtain among the process P1 at optimum phase difference, obtain unit 652 drive controlling rotors 30 by the optimum phase difference of controller 65, adjust the desired driving condition (driving the roughly maximum state of efficient (rotating speed of rotor 30) in the present embodiment) of piezo-activator 20.

Particularly, at first the frequency setting of the drive signal that will be produced by voltage-controlled oscillator 51 is low frequency (being 230kHz in the present embodiment) (step S21), become electric current simultaneously and be restricted to zero state, according to the rotating speed from rotation sensor 15 (Fig. 2) input, the rotary speed of detection rotor 30 (step S22).In the detection of this rotary speed, use two variablees (Z0, Z1) that keep rotating speeds, each when detecting rotary speed with this rotating speed substitution Z0, and relatively Z0 and Z1, when Z0 is bigger than Z1 with Z0 substitution Z1.Thus, in the process of turntable driving frequency, one by one that temporary transient maximum rotative speed is relevant rotating speed substitution Z1 makes its renewal.

Then, compare Z0 and Z1 (step S23), identical or as Z0 when detecting (this rotating speed) and Z1 (rotating speed of being correlated with as temporary transient maximum rotative speed and keep value) than Z1 hour (denying), owing to can't detect the peak value of rotary speed, thereby make driving frequency improve (step S24), and proceed scanning (sweep) with predetermined amplitude.In the present embodiment, the increase rate of the driving frequency during scanning is 0.5kHz, driving frequency from 230kHz to the 280kHz simple scanning.In addition, when carrying out above-mentioned and following driving frequency scanning, also can drop to low frequency from high frequency.

On the other hand, in step S23, when Z0 than Z1 hour (being) surpass peak value owing to be judged as rotary speed, thereby data till will be when detecting and the temporary transient Z1 that keeps is defined as representing the rotating speed of maximum rotative speed (maximum drive efficient), and change next step S25 over to last time.

In step S25, be fixed as the frequency f d that rotating speed is Z1, under this state, measure phase difference (step S26) by phase comparator 63.Here the phase difference of measuring is defined as optimum phase difference, is stored in the memory cell 654 (step S27) of controller 65.In addition, in the piezo-activator 20 that utilizes resonance, need make the phase difference of driving frequency and detection signal roughly keep constant with the value that is suitable for driving, realize the vibration characteristics of being scheduled to, therefore remain in the drive controlling index that optimum phase difference in the memory cell 654 is used as driving control device 50.In the piezo-activator 20 of same specification, because shape and rigging error etc., the optimum phase difference of realizing predetermined driving condition is also different, therefore obtains process P1 by implementing optimum phase difference, can eliminate the deviation of the vibration characteristics that causes owing to individual difference.

Make elapsed time T reset to " 0 " (step S28) at last.

Finish optimum phase difference as mentioned above and obtain process P1, change driving process P2 over to.

[6-3. drives process]

In driving process P2 shown in Figure 8,, at first will obtain the optimum phase difference that is stored in controller 65 among the process P1 and be arranged in the phase shifter 62 (Fig. 4) (step S31) at described optimum phase difference by frequency control unit 651.And, begin turntable driving frequency (S32) from 230KHz, implement the phase difference FEEDBACK CONTROL by phase difference detection unit 60 (Fig. 4) and frequency control unit 651 (Fig. 6).Particularly, make phase difference be " 0 " from phase comparator 63 output, that is, before the optimum phase difference in making phase difference and being set in phase shifter 62 is consistent (step S33), with described same ascensional range turntable driving frequency (step S34).

Like this, make phase difference consistent with optimum phase difference (in step S33, being "Yes"), similarly carry out the phase difference FEEDBACK CONTROL by phase difference detection unit 60 afterwards, implement to make the frequency of drive signal follow the phase difference feedback procedure S35 of the phase difference of detection signal and drive signal.Promptly by frequency control unit 651, the voltage signal of control input voltage control generator 51 makes phase comparator 63 be output as zero, that is, make phase difference become optimum phase difference.

In addition, in phase difference feedback procedure S35,, make the driving time timing variable of the elapsed time T of expression controller 65 increase a counting (step S351) according to each preset clock signal.

Proceed phase difference feedback procedure S35, till the signal input controller 65 that the expression driving finishes (step S36).

Here, when carrying out the drive controlling of piezo-activator 20, with the phase difference of drive signal and detection signal as index (optimum phase difference), carry out the phase difference FEEDBACK CONTROL, but because the Continuous Drive of piezo-activator 20, the time begin through the scheduled time from starting, between projection 25 and rotor 30, produce wearing and tearing, perhaps because changes such as the pressurized conditions of 25 pairs of rotor 30 application of forces of projection and may make the resonance point change.Therefore, by being the phase difference of maximum with the driving efficient that makes piezo-activator 20 at first, the optimum phase difference of promptly realizing desired driving condition is that target is carried out the phase difference FEEDBACK CONTROL, though suitably the drive controlling piezo-activator 20, but owing to vibration characteristics in time through changing, the optimum phase difference itself that drives the efficient maximum that can make that should become index in driving control device 50 changes, and may cause obtaining suitable torque.

The drive characteristic of such piezo-activator 20 through the time change, shown in the curve chart of Fig. 9.

The rotating speed of the rotor 30 in the curve chart of Fig. 9 shown in the solid line, the electric current of piezo-activator 20 and phase difference are respectively the value during turntable driving frequency (curve chart transverse axis) under the initial condition when piezo-activator 20 starting, among Fig. 9, from this initial condition after one hour, after three hours rotating speed, electric current and the phase difference during the turntable driving frequency represent by diverse dotted line respectively.

Shown in this curve chart, the rotating speed during the turntable driving frequency, electric current and phase difference and non-constant, but from initial condition in time process and change.In the present embodiment, the resonance point of the vibrating body 20A of piezo-activator 20 (Fig. 9 medium speed is near the driving frequency the 2500rpm time) is R when initial ₀, be R after one hour ₁, be R after three hours ₃, improve so gradually, therefore, the rotating speed during the turntable driving frequency, electric current and phase difference be drift thereupon also.As the major reason of their drifts, consider the wearing and tearing between the projection 25 of for example rotor 30 and vibrating body 20A, perhaps the change of the pressurized conditions of the power that applies of 25 pairs of rotor 30 butts of projection etc. etc.

Corresponding to the drive characteristic of such piezo-activator 20 through the time change, when the phase difference FEEDBACK CONTROL of the process of driving P2 is passed through the scheduled time, the frequency control unit 653 of controller 65 judges that elapsed time T reaches Continuous Drive time N (step S37 among Fig. 8), implements optimum phase difference shown in Figure 7 once more and obtains process P1.That is, optimum phase difference is obtained process P1 and is stored in the Continuous Drive time (one hour) in the controller 65 according to each and repeats enforcement, upgrades the value that is defined as optimum phase difference.In example shown in Figure 9, the value that is defined as optimum phase difference is θ under initial condition ₀(about 100 degree) by contrast, after one hour, have been implemented to be θ after optimum phase difference is obtained process P1 ₁(about 103 degree).Also regularly implement optimum phase difference after two hours, after three hours and obtain process P1, and will be after starting beginning three hours, implemented the θ after optimum phase difference is obtained process P1 ₃(about 102 degree) are defined as optimum phase difference.For four hours every similarly optimum phase differences that promptly upgraded through a hour of later situation.

Like this, corresponding to because of through the time change the skew of the resonance point cause, the value that keeps as optimum phase difference is proofreaied and correct, can be the drive controlling that prerequisite is suitably carried out driving control device 50 therefore with this optimum phase difference.

[the 7. effect of present embodiment]

According to present embodiment, can obtain following effect.

(1) drives second driving control device 50 of the piezo-activator 20 of timing pin 7A and have controller 65, and implement optimum phase difference by the frequency control unit 653 that this controller 65 has with predetermined frequency and obtain process P1.Thereby, even for realize the predetermined necessary optimum phase difference of driving condition (driving the maximum necessary optimum phase difference of efficient for making in the present embodiment) because of through the time change and wait under the situation about changing, also can obtain process P1, stipulate optimum phase difference once more and proofread and correct to be suitable optimum phase difference by each enforcement optimum phase difference.That is, owing to can guarantee the appropriateness of optimum phase difference, thereby can in the process of driving P2, implement suitable drive controlling according to this optimum phase difference, realize desired driving efficient thereby can drive necessary torque by rotor 30.

(2) in the driving process P2 of driving control device 50, driving frequency is fixed, optimum phase difference with the realization maximal efficiency is a desired value, utilize the phase difference feedback to carry out the control of following of driving frequency, therefore can bring into play the driveability of piezo-activator 20 to greatest extent, make to drive the efficient maximum.

(3) driving control device 50 is packed in the electronic watch 1 as wrist-watch, thereby can irrespectively carry out suitable drive controlling, can increase above-mentioned effect with the change of load etc.

The driving control device 50 of present embodiment be applicable to can wait in violent outdoor of variations in temperature use in the environment or according to carrying the wrist-watch that posture causes load variations, power or drive because of Continuous Drive makes projection 25 wearing and tearing of rotor 30 and vibrating body 20A or the second hand that is easy to generate heat is specially adapted to have high input.Thus, can realize accurate and stable pointer running.

(4) supply with the frequency of drive signal of piezoelectric element 22 of piezo-activator 20 between the resonance frequency fr2 of the resonance frequency fr1 of extensional vibration and flexural vibrations, the amplitude of extensional vibration and flexural vibrations is increased, improve the driving efficient of piezo-activator 20, and, because by a drive piezo-activator 20, so can simplified structure.

In addition, utilizing under the situation of resonance like this, the scope of driving frequency is narrow, the control difficulty of driving frequency, since through the time change and individual difference causes the resonance point deviation and causes the driving condition instability easily, therefore guarantee the appropriateness and the stable effect highly significant of drive controlling by driving control device 50.

In addition, driving control device 50 can also be general as utilizing the piezoelectric actuator drive control device of resonance except piezo-activator 20.

(5) in addition, the driver element of the hour hands 4 of electronic watch 1, minute hand 5 and second hand 6 etc. adopts stepping motor usually, but this stepping motor can be replaced with piezo-activator 20, thereby make electronic watch 1 further realize slimming, and, therefore can improve the high diamagnetic voltinism energy of electronic watch 1 because piezo-activator 20 is compared with stepping motor and is difficult to be subjected to effect of magnetic influence.

[second execution mode]

Below second execution mode of the present invention is described.

In addition, be marked with identical symbol and omission or schematic illustration for the structure identical in the following description with the execution mode that has illustrated.

In the first embodiment, be used for drive controlling with maximal efficiency drive pressure electric actuator 20, but in second execution mode, be, make the driving amount of the driven member that drives by piezo-activator 20 can carry out drive controlling with adjusting with the difference of first execution mode.

Figure 10 is the block diagram of structure of driving control device 50A of the piezo-activator 20 of expression second execution mode.

Driving control device 50A also has except the structure of aforesaid driving control device 50 (Fig. 4): the current detector 71 that detects the electric current that flows through piezo-activator 20 parts; The current instruction value source 72 of output current command value; And, controller 65 is exported the current controller 73 of control signals according to by the current value of current detector 71 detections and the current instruction values of 72 outputs from the current instruction value source.

In addition, in controller 65, according to the output signal of current controller 73, to voltage-controlled oscillator 51 output voltage signals.Promptly carry out FEEDBACK CONTROL in the present embodiment based on the current value of piezo-activator 20.

In such present embodiment, except aforementioned effect, also has following effect.(6) controller 65 can be adjusted according to the current value of piezo-activator 20 to the voltage signal of voltage-controlled oscillator 51 output, therefore can control the vibrational state of piezo-activator 20, can control the rotating speed of rotor 30 etc. thus.Thereby can be the drive source of the driven member of representative with rotor 30 also with piezo-activator 20 as what need carry out speed adjustment (speed control).And, can carry out suitable and stable drive controlling to piezo-activator 20 by the feedback of such current value.

[the 3rd execution mode]

Below the 3rd execution mode of the present invention is described.

In the 3rd execution mode, by with the second execution mode diverse ways, basic the samely with second execution mode, make rotating speed can carry out drive controlling as the rotor of the driven member of piezo-activator 20 with adjusting.

Figure 11 represents the driving control device 50B of the 3rd execution mode.

Driving control device 50B also has except the structure of aforementioned driving control device 50 (Fig. 4): the revolution detector 81 of the rotating speed of detection rotor; The rotary speed instruction value source 82 of output speed command value; And, controller 65 is exported the rotational speed governor 83 of control signals according to by the rotating speed of revolution detector 81 detections and the rotary speed instruction values of 82 outputs from rotary speed instruction value source.

Revolution detector 81 for example comprises the rotation sensor 15 of the rotating speed of the gear 41 (Fig. 2) of detection and rotor 30 one in the first embodiment.

Figure 12 is the flow chart that the optimum phase difference of expression the 3rd execution mode is obtained process P1 '.

Obtain among the process P1 ' at optimum phase difference, at first with revolution detector 81 zero setting (step S20).After this, obtain process P1 (Fig. 7) implementation step S21～step S28 similarly with aforesaid optimum phase difference.Continue to carry out the rotating speed detection of rotor 30 therebetween, by revolution detector 81.

And,, make to begin rotor rotated 30 constantly from step S20 and be inverted to rotating speed and be " 0 " (amount of movement recuperation at last by revolution detector 81, rotary speed instruction value source 82 and rotational speed governor 83; Step S29).After this, when changing driving process P2 (Fig. 8) over to, added optimum phase difference and obtained the command value of the required time of process P1 ', by the timing parts input speed command value source 82 of circuit substrate, therefore can adjust the rotating speed of rotors 30 by rotational speed governor 83.

In addition, in the process of driving P2, also continue to implement the rotating speed detection of rotor 30 by revolution detector 81.

In such present embodiment, except the effect that obtains in the first embodiment, also obtained following effect.

(7) in described second execution mode, controller 65 is controlled according to the current value that flows through piezo-activator 20, but because making by friction, piezo-activator 20 drives rotor 30 rotations, so may take place to slide etc., have the problem that only can how much produce error by the control of current value.To this,,, thereby can more accurately carry out drive controlling owing to direct rotating speed to rotor 30 or gear 41 detects according to the structure of present embodiment.

(8) obtain among the process P1 ' at optimum phase difference, implementation step S20 and step S29, after the cancellation optimum phase difference is obtained the rotation of rotor 30 of process P1 ', in the process of driving P2, obtain the required time of process P1 ' according to optimum phase difference, adjust the rotating speed of rotor 30, thereby can obtain the enforcement of process Pl ' by optimum phase difference, eliminate the error of the pointer running of second timing pin 7A.

[the 4th execution mode]

Below the 4th execution mode of the present invention is described.

The driving control device 50C of present embodiment shown in Figure 13 made up second execution mode based on the drive controlling of current value and the drive controlling based on rotating speed of the 3rd execution mode.

That is, driving control device 50C has: current detector 71; Current controller 73; Revolution detector 81; Rotary speed instruction value source 82; And rotational speed governor 83.

Rotational speed governor 83 bases are from the rotary speed instruction value in rotary speed instruction value source 82 and the rotating speed that is detected by revolution detector 81, to current controller 73 output current command value.

Current controller 73 is exported control signals according to from the current instruction value of rotational speed governor 83 and the current value that is detected by current detector 71 to controller 65.

Therefore, in the FEEDBACK CONTROL of present embodiment, be major cycle, and serve as secondary circulation with Control Circulation based on current value with Control Circulation based on rotor speed.

In such present embodiment, except the effect that in each execution mode of aforementioned the first～three, obtains, also obtained following effect.

(9) according to the rotating speed of the rotor 30 that drives by piezo-activator 20 rotation with flow through these two parameters of current value of piezo-activator 20, the vibrational state of control piezo-activator 20, thereby can more accurately control the rotating speed (rotary speed) of rotor.

[the 5th execution mode]

Below the 5th execution mode of the present invention is described.In aforesaid first～the 4th execution mode, obtaining optimum phase difference repeatedly with predetermined frequency is common trait, and be from the common trait of the 5th execution mode to the eight execution modes, obtain the frequency that the phase difference counter-rotating takes place when driving frequency scans, the driving frequency of phase difference feedback is carried out clamper according to this frequency.

Shuo Ming piezoelectric actuator drive control device and drive controlling method in the present embodiment, with aforementioned first execution mode similarly, can be applicable to the piezo-activator 20 of the timing second pin 7A that drives hour hands 1.Therefore, except with reference to Fig. 1～Fig. 3 shown in first execution mode and Fig. 5, go back Figure 14～Figure 22 with reference to the feature of expression present embodiment.

[structure of the drive unit of 5-1. piezo-activator]

Figure 14 represents the structure of the piezoelectric actuator drive control device 50D of present embodiment.

In the phase shifter 62 ' that driving control device 50D has, preestablished the target phase difference of the index of the drive controlling that becomes piezo-activator 20.Thus, the controller 265 that driving control device 50D has passes through the deviation of the phase difference of low pass filter 64 inputs with respect to target phase difference to voltage-controlled oscillator 51 output voltage signals with elimination.

Figure 15 is the structure skeleton diagram as the controller 265 of control unit, and controller 265 comprises following each structure: make the frequency of drive signal follow the frequency control unit 651 of the phase difference of feedback by phase difference detection unit 60; Whether the phase difference of the phase place of the phase place of detection drive signal and detection signal obtains repeatedly the phase difference counter-rotating detecting unit 655 of the value of target phase difference when the scanning of driving frequency; The clamper unit 656 of restriction driving frequency; And the memory cell 657 that stores the form data TBL (Figure 18) of driving frequency.

Frequency control unit 651 performances in the controller 265 make the frequency of drive signal follow the function of the device of the phase difference that feeds back by phase difference detection unit 60, to voltage-controlled oscillator 51 output voltage signals, with the deviation of elimination with the target phase difference of being imported.

Here, controller 265 has: the initialize mode M1 (Figure 19) of conduct first process of implementing when the driving of piezo-activator 20 begins (phase difference counter-rotating testing process); Drive pattern M2 (Figure 20) with conduct second process of work after initialize mode M1.

Among the form data TBL in being stored in memory cell 657 (Figure 18), store the clamper frequency that relates to the counter-rotating of this phase difference under the situation that when in advance the frequency of the drive signal of supplying with vibrating body 20A being scanned, reaches target phase difference once more.

Phase difference, the rotating speed of rotor 30 and the curve chart that flows through the current value of piezo-activator 20 of vibrating body 20A when Figure 16 is the frequency of expression scanning drive signal, Figure 17 be Figure 16 want portion's enlarged drawing.In addition, this curve chart exists the individual difference because of vibrating body 20A to make numerical value or the different situation of increase and decrease gradient.

The phase difference of drive signal and detection signal is the vibration characteristics index of vibrating body 20A, in the present embodiment, with the phase difference of the roughly maximum optimal drive state of the rotating speed of rotor 30 (predetermined driving condition) G as target phase difference θ (about 100 degree in the present embodiment).When phase difference was this target phase difference θ, the resonance of extensional vibration and flexural vibrations by vibrating body 20A can be with maximal efficiency drive pressure electric actuator 20.

In driving control device 50D, when carrying out the FEEDBACK CONTROL of phase difference, the increase and decrease gradient of the phase difference when making driving frequency scanning is towards a direction and comprise optimal drive state G, sets the stable driving scope A of vibration characteristics.Drive among scope A at this, make driving frequency when the rising direction changes, phase difference has the trend that reduces, based on respect to the driving frequency of the phase place extent of target phase difference θ to follow direction nonreversible.

Here, on vibrating body 20A, drive the phase place of the extensional vibration that produces and the reasons such as phrase overlap of flexural vibrations owing to the applying error of piezoelectric element 22 and stiffener 21 and to drive signal of vibrating body 20A supply, as shown in figure 16, when from the low frequency side along ascent direction turntable driving frequency, in the scope of driving A, have after phase difference reduces from target phase difference θ, increase and reach the situation (rollback point Pt1) of target phase difference θ once more.On this rollback point Pt1, phase difference increases, opposite with the gradient (minimizing) of the phase difference of optimal drive state G, the scope of return contact Pt2 from the increase and decrease gradient of this rollback point Pt1 before reach target phase difference θ again and revert to counter-rotating is considered as the unsettled phase difference counter-rotating of phase difference FEEDBACK CONTROL scope Z.

Be provided with phase difference reversal frequency T1 apart from rollback point Pt1 as shown in figure 17 to have in the both sides of this phase difference counter-rotating scope Z-the reversible scope R1 of phase difference of the amplitude of 0.5kHz, and have+the phase difference recovery scope R2 of the amplitude of 0.5kHz apart from the recovery frequency T3 of phase retrieval point Pt2.Promptly, the boundary value of the reversible scope R1 of phase difference is phase difference reversal frequency T1 and deducts the clamper frequency T2 of 0.5kHz from this phase difference reversal frequency T1, and the boundary value that phase difference restores scope R2 is for restoring frequency T3 and restoring frequency T3 clamper frequency T4 when increasing the recovery of 0.5kHz from this.

Enumerated the reversible scope R1 of phase difference of clamper frequency T4 when comprising these phase difference reversal frequencies T1, clamper frequency T2, recovery frequency T3 and recovery and the frequency that phase difference restores scope R2, and they have been stored in the memory cell 657.

Figure 18 represents to be stored in the data content in the memory cell 657.Memory cell 657 is stored the frequency of reversible scope R1 of phase difference and phase difference recovery scope R2 as form data TBL.

[drive controlling of 5-2. piezo-activator]

Describe below with reference to Figure 19 and flow chart shown in Figure 20 driving process the piezo-activator 20 that undertaken by driving control device 50D.

The controller 265 of driving control device 50D is carried out the initialize mode M1 (Figure 19) as first process when the driving of piezo-activator 20 begins, carry out the drive pattern M2 (Figure 20) as second process then.

[5-2-1. initialize mode]

In initialize mode M1 shown in Figure 19, make rotor 30 rotations, adjust the optimal drive state (the state G (Figure 16) that the present embodiment medium speed is roughly maximum) of piezo-activator 20, and when the turntable driving frequency, judge driving frequency whether to reach target phase difference θ once more and the phenomenon (S41, S42) that the evaluation of phase difference size is reversed takes place.Here target phase difference θ is set in the phase shifter 62.

In these processes S41, S42, particularly, phasing back detecting unit 655 by controller 265, the frequency of the drive signal that from 230kHz to 280kHz voltage-controlled oscillator 51 is produced is carried out simple scanning (sweep), carries out the phase difference feedback processing by phase difference detection unit 60 simultaneously.

And as shown in figure 16, under the situation that the phase difference reversal development takes place, the judged result of this phase difference counter-rotating is a "Yes", generates form data TBL (Figure 18) (S43), and this form data TBL is stored in (S44) in the memory cell 657.

On the other hand, under the situation that the phase difference reversal development does not take place, the judged result of this phase difference counter-rotating is a "No", in the present embodiment, and with the data deletion of the form data TBL in the memory cell 657.

Finish initialize mode M1 as mentioned above, change drive pattern M2 over to.

[5-2-2. drive pattern]

In drive pattern M2 shown in Figure 20, by controller 265, begin the frequency of the drive signal that produced by voltage-controlled oscillator 51 is scanned (S51) from 230kHz, and begin to make the frequency of drive signal to follow the feedback processing (S52) of the phase difference of detection signal and drive signal.

In feedback processing S52, voltage signal to controller 265 outputs is controlled (S521), make phase comparator 63 be output as zero, promptly, make phase difference become target phase difference θ, whenever generating this voltage signal and during to voltage-controlled oscillator 51 outputs, whether the frequency of judging driving frequency that the voltage signal that will generate represents and form data TBL (Figure 18) by clamper unit 656 consistent (S522).

When driving frequency of representing when the voltage signal that will generate and the frequency of form data TBL are inconsistent (denying), generate this voltage signal and to voltage-controlled oscillator 51 outputs, its result changes the frequency of the drive signal that voltage-controlled oscillator 51 produces.

That is, when driving condition is Q1, have the phase difference overgauge D1 bigger with respect to target phase difference θ, at this moment, driving frequency changes to the direction that rises, and phase difference is reduced.In addition, when driving condition is Q2, have the phase difference minus deviation D2 less with respect to target phase difference θ, at this moment, driving frequency changes to the direction that descends, and phase difference is increased.

As long as should be inconsistent with the frequency of form data TBL, just carry out these processes S521 and S522 repeatedly by the driving frequency that the voltage signal that controller 265 generates is represented.

Thus, can tackle well owing to Continuous Drive makes the situation of vibrating body 20A heating or changes because of the attitude of variation of ambient temperature or electronic watch 1 that resonance point that the load variations that causes etc. causes vibrating body 20A changes and the situation of vibration characteristics change.

In addition, in the initialize mode M1 that implements before this, when not producing the phase difference counter-rotating, in the present embodiment, do not carry out the whether consistent judgement (S522) of frequency in driving frequency that voltage signal represents and the form data TBL, but when importing detection signal, the voltage signal that controller 265 generates is controlled (S521) at every turn.

But, in the present embodiment, when the phase difference counter-rotating does not take place when, the form data TBL of memory cell 657 is empty, no matter therefore whether produce the phase difference counter-rotating, even driving frequency and form data TBL that voltage signal is represented compare, judge (S522), in process S522, also be judged as "No" all the time, can normally carry out drive controlling.

On the other hand, when the frequency of the voltage signal that should be generated by controller 265 and form data TBL (Figure 18) is consistent (being), to the generation of this voltage signal, export processing and carry out clamper (S523).

Correspondingly, keep the frequency of the drive signal of voltage-controlled oscillator 51 generations, the restriction driving frequency is to the following of phase difference, thereby can prevent that driving frequency from reaching phase difference reversal frequency T1 through clamper frequency T2, and prevents to follow the direction counter-rotating based on the driving frequency of phase difference.

Here, suppose do not limiting under the situation of following of driving frequency to phase difference, have the driving condition Q3 of the driving condition of piezo-activator 20, move to the possibility of driving condition Q4 through the reversible scope R1 of phase difference.Under this driving condition Q4, make it near optimal drive state G although need to reduce driving frequency, because phase difference is big (+) with respect to target phase difference θ,, phase difference is reduced so cause driving frequency to change to ascent direction.

Promptly in the front and back of rollback point Pt1, reverse with respect to the direction of following of the driving frequency of the size of target phase difference θ based on phase difference, therefore driving frequency is towards changing in the opposite direction with suitable side, driving condition is moved to driving condition Q5 from driving condition Q4, and promptly driving condition moves to the direction of leaving optimal drive state G.Between this driving condition Q4 and Q5, the increase and decrease gradient of phase difference changes, afterwards, front and back at the target phase difference θ return contact Pt2 identical with the phase difference rank, change driving frequency by the phase difference feedback, even the driving condition of piezo-activator 20 is away from optimal drive state G, also can't get back near the state of optimal drive state G basically.

For fear of this unfavorable condition, limit driving frequency following as previously mentioned to phase difference.

Here, because following or variations in temperature to phase difference, and with the clamper frequency T2 of the amplitude bigger than the Oscillation Amplitude of driving frequency (0.5kHz) setting away from phase difference reversal frequency T1, as previously mentioned, by driving frequency being limited avoiding it to reach clamper frequency T2, thereby can reliably prevent under the state of the evaluation counter-rotating of phase difference, to carry out FEEDBACK CONTROL.

In addition, after clamper (S523), return course S521 proceeds the processing corresponding to the detection signal of back, is under the situation of "No" in process S522, makes the frequency of drive signal follow phase difference.

As mentioned above, fixed drive frequency and make it follow phase difference not, the change of the vibration characteristics of the vibrating body 20A that can tackle because variations in temperature etc. causes, even and under the situation of phase difference generation reversal development, also drive controlling piezo-activator 20 stably, and avoid controlling and driving frequency on the direction of dislocation.

Here, in the form data TBL of memory cell 657 (Figure 18), except the reversible scope R1 of phase difference, also store the frequency data that phase difference restores scope R2, the value that this phase difference restores scope R2 is used for following situation.

For example, preferably when reference clamper frequency T2 carries out clamper to the output of the voltage signal of controller 265, need float to situation that the driving scope J (Figure 16) than the more close high frequency side of return contact Pt2 drives etc., restore the frequency of scope R2 with reference to this phase difference, and the restriction driving frequency, avoid making the driving condition instability.Promptly driving frequency is followed in the processing of phase difference, before the change driving frequency, judging that whether the driving frequency that will change and phase difference restore the interior value of scope R2 consistent, carries out clamper to processing, to keep driving frequency under the situation of unanimity.

If carry out such drive controlling, then can stably carry out drive controlling removing under the state that makes the unsettled phase difference counter-rotating of drive controlling scope Z.

In addition, be positioned at more close high frequency side than return contact Pt2 at the optimal drive state, and need be in driving scope J under the situation of drive pressure electric actuator 20, also can similarly restore the processing that scope R2 limit driving frequency with reference to this phase difference.

In addition, phase difference in the time of also can considering driving frequency scanning as shown in figure 16, increase repeatedly, reduce, and make phase difference increase and decrease gradient and non-constant situation, and phase difference situation about taking place in a plurality of positions with respect to the reversal development of the evaluation of the target phase difference that sets (for example θ ' among Figure 16).

In this case, work out: the driving frequency that reversible scope of the phase difference of these backward positions and phase difference restore scope also can be appended among the form data TBL (Figure 18), is used for drive controlling.

In view of the above, in the gamut of the 230kHz～280kHz that driving frequency is scanned except the scope of phase difference counter-rotating, can pass through driving control device 50D drive controlling piezo-activator 20.

Figure 21 is the curve chart of drive characteristic of expression piezo-activator 20, Figure 22 be expression in order to compare with Figure 21, in this piezo-activator 20, the curve chart of the drive characteristic when not carrying out the driving frequency restriction.In these Figure 21, Figure 22, the Continuous Drive time of pressure electric actuator 20 is transverse axis.

If implement the driving frequency restriction, although then be in the environment that makes vibrating body 20A be easy to generate heat owing to Continuous Drive, also can suppress the amplitude up and down of driving frequency as shown in figure 21, make the stabilization of speed of rotor 30.Relative therewith, as can be known, the reasons such as variations in temperature owing to being accompanied by vibrating body 20A heating cause the driving frequency dipping and heaving in Figure 22, can not the rotating speed of rotor 30 be improved in this part that changes up and down, and driving condition is very unstable.

That is, can confirm: because the driving frequency of being undertaken by described driving control device 50D restriction, can be regardless of variations in temperature etc., and stably carry out the drive controlling of piezo-activator 20.

[effect of 5-3. present embodiment]

According to present embodiment, can obtain following effect.

(10) in the controller 265 that the driving control device 50D of piezo-activator 20 has, when the frequency that makes drive signal is followed the phase difference that is detected by phase difference detection unit 60, reference is stored in the form data TBL in the memory cell 657 in initialize mode M1, implement the restriction of driving frequency, the feasible driving frequency that driving frequency when following phase difference is reached under the clamper frequency T2 situation is carried out clamper to following of phase difference.Therefore, when driving frequency is scanned,, also can prevent the oppositely abnormality processing of change of driving frequency, and implement stable drive controlling even take place under the situation of counter-rotating in evaluation with respect to the phase difference size of target phase difference θ.

(11) when the driving frequency scanning of being undertaken by controller 265, to be set in optimal drive state G side from the clamper frequency T2 that phase difference reversal frequency T1 leaves 0.5kHz, can controlling and driving frequency following to phase difference, to avoid reaching the value of this clamper frequency T2, therefore, also can prevent from reliably driving frequency to be followed to unsuitable direction owing to the reversal development of the evaluation of phase difference even the variation owing to driving frequency makes driving condition near rollback point Pt1.

In addition, clamper frequency T2 preferably is about 1.98mm, long limit at the minor face of vibrating body 20A and is about that 7mm, target phase difference are about 100 degree, driving frequency is about under the situation of 250kHz, leaves the scope of 0.3kHz～0.7kHz from phase difference reversal frequency T1.

Promptly when clamper frequency T2 leaves phase difference reversal frequency T1 and approximately exceeds 0.7kHz, even very little variation takes place in ambient temperature or load, also can stop driving frequency to the following of phase difference, can't carry out the control corresponding to the driving frequency of temperature or load later on, be unfavorable therefore.I.e. variation owing to temperature or load might cause the driving condition instability, and causes the drive controlling performance to reduce.

On the other hand, as clamper frequency T2 during from quantity not sufficient 0.3kHz that phase difference reversal frequency T1 leaves, owing to frequency is implemented variable control according to phase difference, and can not prevent that driving frequency from becoming the frequency range of phasing back, causes the drive controlling instability.

(12) controller 265 has the initialize mode M1 that carries out when driving beginning, when initialize mode M1, the form data TBL that has enumerated the frequency of the reversible scope R1 of phase difference is stored in the memory cell 657, therefore when piezo-activator 20 each startings, the information of the reversible scope R1 of phase difference that can updated stored unit 657, and, implement drive controlling according to the last state of piezo-activator 20.

Here, also can study to carrying out initialize mode M1 with predetermined spaces such as for example every several hrs.

In addition, frequency with the reversible scope R1 of phase difference is stored in the memory cell 657 as form data TBL in advance, therefore do not need in controller 265 that each phase difference feedback is all carried out clamper frequency T2, the setting of clamper frequency T4 etc. when restoring, thus can simplified structure.

(13) by driving control device 50D is installed in as the electronic watch 1 of wrist-watch, can be regardless of the variation of temperature or load, and carry out stable drive controlling, make described effect more remarkable.

The driving control device 50D of present embodiment be applicable to wait in violent outdoor of variations in temperature use in the environment or according to carrying the wrist-watch that posture causes load variations, be specially adapted to have high input power or the second hand that is easy to generate heat because of Continuous Drive drives.Thus, can realize accurate and stable pointer running.

(14) frequency of the drive signal of the piezoelectric element 22 of supply piezo-activator 20 is between the resonance frequency fr1 and flexural vibrations resonance frequency fr2 of extensional vibration, the amplitude of extensional vibration and flexural vibrations is increased, improve the driving efficient of piezo-activator 20, and, because by a drive piezo-activator 20, so can simplified structure.

In addition, like this, utilizing under the situation of resonance, the scope of driving frequency is narrow, the control difficulty of driving frequency, because variations in temperature etc. causes the resonance point deviation and causes the driving condition instability easily, therefore guarantees the effect highly significant of the stability of drive controlling by driving control device 50D.

In addition, driving control device 50D can also be general as utilizing the piezoelectric actuator drive control device of resonance except piezo-activator 20.

(15) in addition, the driver element of the hour hands 4 of electronic watch 1, minute hand 5 and second hand 6 etc. adopts stepping motor usually, but owing to this stepping motor can be replaced with piezo-activator 20, thereby make electronic watch 1 further slimming, and, therefore also can improve the high diamagnetic voltinism energy of electronic watch 1 because piezo-activator 20 is compared with stepping motor and is difficult to be subjected to effect of magnetic influence.

[the 6th execution mode]

Below the 6th execution mode of the present invention is described.

In the 5th execution mode, carried out being used for drive controlling with maximal efficiency drive pressure electric actuator 20, but in the 6th execution mode, be, make the driving amount of the driven member that drives by piezo-activator 20 can carry out drive controlling with adjusting with the difference of the 5th execution mode.

Figure 23 is the block diagram of structure of driving control device 50E of the piezo-activator 20 of expression the 6th execution mode.

Driving control device 50E also has except the structure of aforementioned driving control device 50D (Figure 14): the current detector 71 that detects the electric current that flows through piezo-activator 20 parts; The current instruction value source 72 of output current command value; And, controller 265 is exported the current controller 73 of control signals according to by the current value of current detector 71 detections and the current instruction values of 72 outputs from the current instruction value source.

In addition, in controller 265, according to the output signal of current controller 73, to voltage-controlled oscillator 51 output voltage signals.Promptly carry out FEEDBACK CONTROL in the present embodiment based on the current value of piezo-activator 20.

In such present embodiment, except aforementioned effect, also obtained following effect.

(16) controller 265 can be adjusted according to the current value of piezo-activator 20 to the voltage signal of voltage-controlled oscillator 51 output, thereby can control the vibrational state of piezo-activator 20, thus the rotating speed of rotor 30 etc. is controlled.Therefore can be the drive source of the driven member of representative as what need carry out speed adjustment (speed control) with rotor 30 with piezo-activator 20.And, can carry out stable drive controlling to piezo-activator 20 by the feedback of such current value.

[the 7th execution mode]

Below the 7th execution mode of the present invention is described.

In the 7th execution mode, by with the 6th execution mode diverse ways, basic the samely with the 6th execution mode, make rotating speed can carry out drive controlling as the rotor of the driven member of piezo-activator 20 with adjusting.

Figure 24 represents the driving control device 50F of the 7th execution mode.

Driving control device 50F also has except the structure of aforementioned driving control device 50D (Figure 14): the revolution detector 81 of the rotating speed of detection rotor; The rotary speed instruction value source 82 of output speed command value; And, controller 265 is exported the rotational speed governor 83 of control signals according to by the rotating speed of revolution detector 81 detections and the rotary speed instruction values of 82 outputs from rotary speed instruction value source.

Revolution detector 81 for example has in the first embodiment the rotation sensor 15 that the rotating speed with the gear 41 (Fig. 2) of rotor 30 one is detected.

In such present embodiment, except the effect that in the 5th execution mode, obtains, also obtained following effect.

(17) in described the 6th execution mode, controller 265 is controlled according to the current value that flows through piezo-activator 20, but drive rotor 30 rotations owing to piezo-activator 20 makes by friction, therefore may take place to slide etc., have the problem that only how much can produce error by the control of current value.To this,,, thereby can more accurately carry out drive controlling owing to direct rotating speed to rotor 30 or gear 41 detects according to the structure of present embodiment.

[the 8th execution mode]

Below the 8th execution mode of the present invention is described.

The driving control device 50G of present embodiment shown in Figure 25 made up the 6th execution mode based on the drive controlling of current value and the drive controlling based on rotating speed of the 7th execution mode.

That is, driving control device 50G has: current detector 71; Current controller 73; Revolution detector 81; Rotary speed instruction value source 82; And rotational speed governor 83.

Rotational speed governor 83 bases are from the rotary speed instruction value in rotary speed instruction value source 82 and the rotating speed that is detected by revolution detector 81, to current controller 73 output current command value.

Current controller 73 is exported control signals according to from the current instruction value of rotational speed governor 83 and the current value that is detected by current detector 71 to controller 265.

Therefore, in the FEEDBACK CONTROL of present embodiment, be major cycle, and serve as secondary circulation with Control Circulation based on current value with Control Circulation based on rotor speed.

In such present embodiment, except the effect that in each execution mode of the aforementioned the five～seven, obtains, also obtained following effect.

(18) according to the rotating speed of the rotor 30 that drives by piezo-activator 20 rotation with flow through these two parameters of current value of piezo-activator 20, the vibrational state of control piezo-activator 20, thereby can more accurately control the rotating speed (rotary speed) of rotor.

[the 9th execution mode]

Below the 9th execution mode of the present invention is described.Present embodiment is with the feature of first execution mode and the feature of the 5th execution mode.Shuo Ming piezoelectric actuator drive control device and drive controlling method in the present embodiment, with aforementioned first execution mode similarly, also can be applicable to the piezo-activator 20 of the timing second pin 7A that drives hour hands 1.Therefore, except Fig. 1～Fig. 3 shown in reference first execution mode and Fig. 5, also with reference to Figure 26～Figure 29.

[structure of the drive unit of 9-1. piezo-activator]

Figure 26 represents the structure of the piezoelectric actuator drive control device 50H of the 9th execution mode.

Figure 27 is the structure skeleton diagram as the controller 365 of control unit, and controller 365 comprises following each structure: frequency control unit 651; Optimum phase difference is obtained unit 652; Frequency control unit 653; Phase difference counter-rotating detecting unit 655; Clamper unit 656; And memory cell 658.Here, optimum phase difference is obtained unit 652 and phase difference counter-rotating detecting unit 655 constitutes the initial setting unit by being equipped with.

In memory cell 658, store and the content of aforementioned memory cell 654 (Fig. 6) and the essentially identical content of content of memory cell 657 (Figure 15) the Continuous Drive time (for example one hour) that begins during promptly from piezo-activator 20 startings and the form data of driving frequency.

Here, be stored in the form data in the memory cell 658, store when the frequency of drive signal of vibrating body 20A is supplied with in scanning and reach once more under the situation of optimum phase difference, relate to the clamper frequency of phase difference counter-rotating as described above as shown in Figure 18.I.e. Figure 16 and shown in Figure 17 as described above, in the present embodiment, the phase difference of the optimal drive state that rotor 30 rotating speeds are roughly maximum (predetermined driving condition) G is as optimum phase difference (with reference to θ among Figure 16, Figure 17), can list the reversible scope R1 of phase difference of clamper frequency T4 when comprising aforementioned phase difference reversal frequency T1, clamper frequency T2, recovery frequency T3 and recovery and the frequency that phase difference restores scope R2, and they are stored in the memory cell 658.

[drive controlling of 9-2. piezo-activator]

Below with reference to Figure 28 and flowchart text driving control device 50H shown in Figure 29 effect to piezo-activator 20.

The controller 365 of driving control device 50H is carried out optimum phase difference shown in Figure 28 respectively and is obtained process P1, phase difference counter-rotating testing process P4 and driving process P5 shown in Figure 29.

In addition, optimum phase difference is obtained process P1 and phase difference counter-rotating testing process P4 constitutes the initial setting process by being equipped with.

[effect of 9-2-1. frequency control unit]

Controller 365 is by the timer function of frequency control unit 653, as shown in figure 28, the elapsed time T that affirmation begins when piezo-activator 20 starts i.e. the Continuous Drive time (step S11), implements optimum phase difference with predetermined frequency and obtains process P1 and phase difference counter-rotating testing process P4.Promptly, in the affirmation (step S11) of Continuous Drive time, when the elapsed time T that begins from piezo-activator 20 starting the time reaches Continuous Drive time N the memory cell 658 that is stored in controller 65 (being), implement optimum phase difference and obtain process P1, and (deny) to change driving process P2 shown in Figure 8 over to when not reaching.

In addition, elapsed time T is initialized to zero when piezo-activator 20 startings.

[the 9-2-2. optimum phase difference is obtained process]

Obtain among the process P1 at optimum phase difference, obtain unit 652 drive controlling rotors 30 by the optimum phase difference of controller 365, to adjust the desired driving condition (driving the roughly maximum state of efficient (rotating speed of rotor 30) in the present embodiment) of piezo-activator 20.

Particularly, at first the frequency setting of the drive signal that will be produced by voltage-controlled oscillator 51 is low frequency (being 230kHz in the present embodiment) (step S21), become electric current simultaneously and be restricted to 0 state, according to the rotating speed from rotation sensor 15 (Fig. 2) input, the rotary speed of detection rotor 30 (step S22).In the detection of this rotary speed, use two variablees (Z0, Z1) that keep rotating speeds, each when detecting rotary speed with this rotating speed substitution Z0, and relatively Z0 and Z1, when Z0 is bigger than Z1 with Z0 substitution Z1.Thus, in the process of turntable driving frequency, one by one that temporary transient maximum rotative speed is relevant rotating speed substitution Z1 makes its renewal.

Then, compare Z0 and Z1 (step S23), identical or as Z0 when detecting (this rotating speed) and Z1 (rotating speed of being correlated with as temporary transient maximum rotative speed and keep value) than Z1 hour (denying), owing to can't detect the peak value of rotary speed, thereby make driving frequency improve (step S24), and proceed scanning (sweep) with predetermined amplitude.In the present embodiment, the increase rate of the driving frequency during scanning is 0.5kHz, driving frequency from 230kHz to the 280kHz simple scanning.In addition, when carrying out this driving frequency scanning, also can drop to low frequency from high frequency.

On the other hand, in step S23, work as Z0 than Z1 hour (being), surpass peak value owing to be judged as rotary speed, thereby data till will be when detecting to last time and the temporary transient Z1 that keeps is defined as representing changing next step S25 over to by the rotating speed of maximum rotative speed (maximum drive efficient).

In step S25, be fixed as the frequency f d that rotating speed is Z1, under this state, measure phase difference (step S26) by phase comparator 63.Here the phase difference of measuring is defined as optimum phase difference, is stored in the memory cell 654 of controller 65 (step S27).Optimum phase difference according to storage here carries out following phase difference counter-rotating testing process P4.

In phase difference counter-rotating testing process P4, judge when the turntable driving frequency whether driving frequency reaches optimum phase difference (θ in reference to Figure 16, Figure 17) once more and the phenomenon (S41, S42) that the evaluation of phase difference size is reversed takes place.Here optimum phase difference (θ) is set in the phase shifter 62.

In these processes S41, S42, particularly, phasing back detecting unit 655 by controller 365, the frequency of the drive signal that from 230kHz to 280kHz voltage-controlled oscillator 51 is produced is carried out simple scanning (sweep), implements the phase difference feedback processing by phase difference detection unit 60 simultaneously.And as shown in figure 16, under the situation that the phase difference reversal development takes place, the judged result of passing through clamper unit 656 of this phase difference counter-rotating is a "Yes", generates form data TBL (Figure 18) (S43), and this form data TBL is stored in (S44) in the memory cell 657.

On the other hand, under the situation that the phase difference reversal development does not take place, the judged result of phase difference counter-rotating is a "No", in the present embodiment, and with the data deletion of the form data TBL in the memory cell 658.

Finish above optimum phase difference and obtain after process P1 and the phase difference counter-rotating testing process P4, elapsed time T is reset to " 0 " (step S28), change driving process P5 over to.

[9-2-3. drives process]

In driving process P5 shown in Figure 29,, at first will obtain the optimum phase difference that is stored among the process P1 in the memory cell 658 and be arranged at (Figure 26) (step S31) in the phase shifter 62 at aforementioned optimum phase difference by controller 365.And, begin turntable driving frequency (S32) from 230KHz, implement the phase difference FEEDBACK CONTROL by phase difference detection unit 60 and frequency control unit 651 (Figure 26).Particularly, make phase difference be " 0 " from phase comparator 63 output, that is, before the optimum phase difference in making phase difference and being set in phase shifter 62 is consistent (step S33), with above-mentioned same ascensional range turntable driving frequency (step S34).

Like this, make phase difference consistent with optimum phase difference (in step S33, being "Yes"), similarly carry out the phase difference FEEDBACK CONTROL by phase difference detection unit 60 afterwards, make the frequency of drive signal follow the phase difference feedback procedure S35 of the phase difference of detection signal and drive signal.Promptly by frequency control unit 651, control is input to the voltage signal of voltage-controlled oscillator 51, makes phase comparator 63 be output as zero, that is, make phase difference become optimum phase difference.Here, whenever generating this voltage signal and during to voltage-controlled oscillator 51 outputs, whether the frequency of judging driving frequency that the voltage signal that will generate represents and form data TBL (Figure 18) consistent (S522).

When driving frequency of representing when the voltage signal that will generate and the frequency of form data TBL are inconsistent (denying), generate this voltage signal and to voltage-controlled oscillator 51 outputs, its result changes the frequency of the drive signal that voltage-controlled oscillator 51 produces.

That is, when driving condition is Q1 (Figure 17), have the phase difference overgauge D1 (Figure 17) bigger with respect to optimum phase difference (with reference to θ among Figure 17), at this moment, driving frequency changes towards the rising direction, and phase difference is reduced.In addition, when driving condition is Q2, have the phase difference minus deviation D2 (Figure 17) less with respect to target phase difference (θ), at this moment, driving frequency changes towards the decline direction, and phase difference is increased.

As long as should be inconsistent with the frequency of form data TBL, just carry out these processes S35 and S522 repeatedly by the driving frequency that the voltage signal that controller 365 generates is represented.

In addition, in the phase difference counter-rotating testing process P4 that implements before this, when not producing the phase difference counter-rotating, in the present embodiment, do not carry out the whether consistent judgement (S522) of frequency in driving frequency that voltage signal represents and the form data TBL, but when importing detection signal, the voltage signal that controller 365 generates is controlled (S35) at every turn.

On the other hand, when the frequency of the voltage signal that should be generated by controller 365 and form data TBL (Figure 18) is consistent (being), to the generation of this voltage signal, export processing and carry out clamper (S523).

Correspondingly, keep the frequency of the drive signal of voltage-controlled oscillator 51 generations, the restriction driving frequency is to the following of phase difference, thereby can prevent that driving frequency from reaching phase difference reversal frequency T1 through clamper frequency T2, and prevents to follow the direction counter-rotating based on the driving frequency of phase difference.Thus, can prevent from reliably under the state that the evaluation of phase difference is reversed, to carry out FEEDBACK CONTROL.

In addition, after clamper (S523), return course S35 proceeds the processing corresponding to the detection signal of back, is under the situation of "No" in process S522, makes the frequency of drive signal follow phase difference.

In addition, when carrying out phase difference feedback procedure S35, this series of processes of S522, S523, make the driving time timing variable of the elapsed time T of expression controller 365 increase a counting (step S351) at every turn.

Before the signal that expression drive to finish is input to controller 365 (step S36), perhaps the signal of the switching of the direction of rotation of expression second timing pin 7A is input to (step S38) before the controller 365, proceeds above-mentioned driving process P5.

Here, when carrying out the drive controlling of piezo-activator 20, with the phase difference of drive signal and detection signal as index (optimum phase difference), carry out the phase difference FEEDBACK CONTROL, but it is shown in Figure 9 as the aforementioned, since wearing and tearing that the Continuous Drive of piezo-activator 20 causes or heating etc. cause through the time change, the vibration characteristics of piezo-activator 20 is changed, the optimum phase difference itself that becomes index in the control of driving control device 50H changes, and may cause obtaining suitable torque.

In addition and since such through the time change, cause phase difference reversal frequency T1, clamper frequency T2 etc. also to change, influence drive controlling.

Corresponding to the drive characteristic of such piezo-activator 20 through the time change, when the phase difference FEEDBACK CONTROL of the process of driving P5 is passed through the scheduled time, the frequency control unit 653 of controller 65 judges that elapsed time T has reached Continuous Drive time N (step S37 among Figure 29), implements optimum phase difference shown in Figure 28 once more and obtains process P1 and phase difference counter-rotating testing process P4.That is, optimum phase difference is obtained process P1 and is stored in the Continuous Drive time (one hour) in the controller 365 according to each and repeats enforcement, upgrades the value that is defined as optimum phase difference.And phase difference counter-rotating testing process P4 also is stored in the Continuous Drive time (one hour) in the controller 365 according to each and repeats to implement, and upgrades the value that remains in phase difference reversal frequency T1, clamper frequency T2 etc. in the memory cell 658.

Like this corresponding to because of through the time change the skew etc. of the resonance point cause, value, phase difference reversal frequency T1 and the clamper frequency T2 that keeps as optimum phase difference proofreaied and correct, thereby can be the drive controlling that prerequisite is suitably implemented driving control device 50H with this optimum phase difference.

Here, optionally supply with drive signal to drive electrode 221,222,223 as previously mentioned, thereby can make piezo-activator 20 drive rotor 30 to positive direction and opposite direction, but synthesizing when forward drive and reverse drive of the phase difference of extensional vibration and flexural vibrations is asymmetric, and drive characteristic situation inequality is more.

Therefore, when carrying out positive and reverse return to timing second pin 7A, the user migrates family when operation, when perhaps carrying out time adjustment etc. in the process scheduled time, when the signal that will represent the switching just changeing/reverse by positive and negative rotation circuit 522 (Figure 26) is input to controller 365 (S38 is a "Yes"), the optimum phase difference of implementing is once more as shown in figure 28 obtained process P1 and phase difference counter-rotating testing process P4 (these processes P1 and P2 constitute the initial setting process).

Drive characteristic and the above-mentioned Figure 21 of piezo-activator 20 that carries out drive controlling like this is roughly the same.

[effect of 9-3. present embodiment]

In the present embodiment, except the effect that obtains by aforementioned first execution mode and the 5th execution mode, can also obtain following effect.

(19) carry out optimum phase difference by controller 365 with predetermined frequency and obtain process P1 and phase difference counter-rotating testing process P4, thereby can successfully manage owing to wearing and tearing wait through the time change and variations in temperature etc. causes the situation of resonance point and optimum phase difference change and the situation of reversing sometimes as the vibration characteristics of piezo-activator 20 phase difference when the frequency scanning.Therefore, when driving timing second pin 7A by piezo-activator 20 long-time continuous, also can realize accurate and stable driving.In addition, the environment for use to the table 1 that is equipped with piezo-activator 20 does not require.That is, can further enlarge the scope of application of piezo-activator, can improve reliability and reduce cost.

(20) in addition, when carrying out the switching of just changeing/reversing of second timing pin 7A (S38), the Continuous Drive time (S37) that begins process during with piezo-activator 20 startings is irrelevant, implement optimum phase difference and obtain process P1 and phase difference counter-rotating testing process P4, even thereby under the different situation of the vibrational state characteristic of the vibrating body 20A when rotor 30 is carried out forward drive with reverse drive, also can pass through optimum phase difference, appropriate degree and the stability of driving control device 50H to piezo-activator 20 drive controlling is guaranteed in the renewal of phase difference reversal frequency and clamper frequency etc.

(21) in addition, the single-phase drive signal of frequency between the resonance point (fr1 among Fig. 5) by supplying with from extensional vibration to vibrating body 20A and the resonance point (fr2 among Fig. 5) of flexural vibrations, consider phase place synthetic of the phase place of extensional vibration and flexural vibrations, the reversal development that causes phase difference easily, therefore handle by the detection of aforesaid phase difference reversal frequency with based on the clamper of this detection, can make the effect that realizes stabilized driving more remarkable.

[9-4. modified embodiment of the present embodiment]

In the above-described 9th embodiment, optimum phase difference is obtained process P1 (Figure 28) and is had the step (S21 and S24) of implementing driving frequency scanning (sweep), and phase difference counter-rotating testing process P4 also has the step (S41) of implementing driving frequency scanning, in the processing of these driving frequency scannings (S24 and S24 and S41), the amplitude of the driving frequency that is scanned all is 230kHz～280kHz.

Here, with reference to Figure 30, Figure 31 modified embodiment of the present embodiment is described.

Figure 30 represents the different example of scanning width of driving frequency scanning step (S21, S24 and S41 ').Promptly, the step S21 that optimum phase difference is obtained among the process P1 is different with the situation of Figure 28 with scanning width among the S24, and among the step S41 ' among the counter-rotating of the phase difference below testing process P4, according to obtain the optimum phase difference that process P1 obtains by optimum phase difference, because of through the time change the scope that the phase difference cause resonance point to change making drive signal and detection signal changes, and the scope that in changeable frequency drive controlling, can change driving frequency based on the phase difference feedback, set predetermined frequency scanning width (S40), and with this scanning width (for example 245kHz～260kHz) scan (S41 ').In addition, in step S40, in view of shown in waiting because of Fig. 9 for example through the time change the variation etc. of the resonance point that causes, set the sweep amplitude of driving frequency.Scanning width shown in the S41 ' is an example only.

In addition, Figure 31 represents to make the example of driving frequency scanning step (S21, S24 and S41 ') unification (optimum phase difference is obtained/phase difference counter-rotating testing process P6).At this moment, the frequency that begins to scan in S21 ' for example is 245kHz, till when scanning ("Yes" among the S23) the driving frequency fd when detecting maximum (top) speed (S24) always, in the process till obtain optimum phase difference (S27), also detected phase contrast reversal (S61).In addition, step S41 after obtaining optimum phase difference " in; begin to scan from driving frequency fd,, judge whether driving frequency reaches optimum phase difference once more and the phenomenon (S42) of the evaluation counter-rotating of phase difference size takes place until for example 260kHz corresponding to optimum phase difference.Here, the scanning width from step S21 ' to S27 not with step S41 " scanning width repeat.Under the situation of this Figure 31, the driving frequency that set to realize the driving frequency of optimum phase difference and produce the phase difference counter-rotating is in certain constant scope, with because of through the time change the scope that changes and the amplitude of the driving frequency that the scope that changes because of the phase difference feedback processing is corresponding is implemented to scan.

As the structure of this Figure 31, particularly, constitute controller 365, and handle and be easy to realize by this program being read in information processor with program.

According to the method shown in these Figure 30,31,, therefore can shorten optimum phase difference and obtain process P1 and phase difference counter-rotating required time of testing process P4 owing to be not to repeat driving frequency scanning with identical driving frequency amplitude.Thereby can reduce the influence that the pointer running of timing second pin 7A produced owing to carry out these optimum phase differences to obtain process P1 and phase difference counter-rotating testing process P4.

[the tenth execution mode]

Below the tenth execution mode of the present invention is described.

In the 9th execution mode, carried out being used for drive controlling with maximal efficiency drive pressure electric actuator 20, but in the tenth execution mode, be, make the driving amount of the driven member that drives by piezo-activator 20 can carry out drive controlling with adjusting with the difference of aforementioned each execution mode.

Figure 32 is the block diagram of structure of driving control device 50I of the piezo-activator 20 of expression the tenth execution mode.

Driving control device 50I also has except the structure of aforementioned driving control device 50H (Figure 26): the current detector 71 that detects the electric current that flows through piezo-activator 20 parts; The current instruction value source 72 of output current command value; And, controller 365 is exported the current controller 73 of control signals according to by the current value of current detector 71 detections and the current instruction values of 72 outputs from the current instruction value source.

According to such present embodiment, except the effect of the 9th execution mode, can also obtain the essentially identical effect of driving control device 50A (Figure 10) with aforementioned second execution mode.

[the 11 execution mode]

Below the 11 execution mode of the present invention is described.

In the present embodiment, by with the tenth execution mode diverse ways, basic the samely with the tenth execution mode, make rotating speed can carry out drive controlling as the rotor of the driven member of piezo-activator 20 with adjusting.

Figure 33 represents the driving control device 50J of the 11 execution mode.

Driving control device 50J also has except the structure of aforementioned driving control device 50H (Figure 26): the revolution detector 81 of the rotating speed of detection rotor; The rotary speed instruction value source 82 of output speed command value; And, controller 365 is exported the rotational speed governor 83 of control signals according to by the rotating speed of revolution detector 81 detections and the rotary speed instruction values of 82 outputs from rotary speed instruction value source.

Revolution detector 81 for example has the rotation sensor 15 that the rotating speed with the gear 41 (Fig. 2) of rotor 30 one is detected.

Figure 34 is the flow chart that the optimum phase difference of expression the 11 execution mode is obtained process P1 '.

Obtain among the process P1 ' at optimum phase difference, at first with revolution detector 81 zero setting (step S20).Then, obtain process P1 (Figure 28) implementation step S21～step S27 similarly with aforementioned optimum phase difference, after obtaining optimum phase difference S27 (S27), implement phase difference counter-rotating testing process P4, elapsed time T (S28) then resets.In the process of this S21～S28, continue the rotating speed of rotor 30 is detected by revolution detector 81.

And,, make to begin rotor rotated 30 constantly from step S20 and be inverted to rotating speed and be " 0 " (amount of movement recuperation at last by revolution detector 81, rotary speed instruction value source 82 and rotational speed governor 83; Step S29).After this, when changing driving process P5 (Figure 29) over to, add optimum phase difference and obtained the command value of the required time of process P1 ' and phase difference counter-rotating testing process P4, by the timing parts input speed command value source 82 of circuit substrate, therefore can adjust the rotating speed of rotor 30 by rotational speed governor 83.

In addition, in the process of driving P5, also continue to implement the rotating speed detection of rotor 30 by revolution detector 81.

According to such present embodiment, except the effect of the 9th execution mode, also obtain the roughly the same effect of driving control device 50B (Figure 11) with aforementioned the 3rd execution mode.

[the 12 execution mode]

Below the 12 execution mode of the present invention is described.

The driving control device 50K of present embodiment shown in Figure 35 made up the tenth execution mode based on the drive controlling of current value and the drive controlling based on rotating speed of the 11 execution mode.

That is, driving control device 50K has: current detector 71; Current controller 73; Revolution detector 81; Rotary speed instruction value source 82; And rotational speed governor 83.

Rotational speed governor 83 bases are from the rotary speed instruction value in rotary speed instruction value source 82 and the rotating speed that is detected by revolution detector 81, to current controller 73 output current command value.

Current controller 73 is exported control signals according to from the current instruction value of rotational speed governor 83 and the current value that is detected by current detector 71 to controller 365.

Therefore, in the FEEDBACK CONTROL of present embodiment, be major cycle, and serve as secondary circulation with Control Circulation based on current value with Control Circulation based on rotor speed.

According to such present embodiment, except the effect of the 9th execution mode, also obtain the roughly the same effect of driving control device 50C (Figure 13) with aforementioned the 4th execution mode.

[variation of the present invention]

The invention is not restricted to the respective embodiments described above, allow and carry out various distortion and improvement.

Figure 36 represent can with the driving process P2 ' (first variation) of driving process P2 (Fig. 8) displacement that illustrates in first execution mode.In driving process P2 ', do not drive the phase difference feedback procedure S35 that process P2 is had, and generation carry out drive controlling (step S75) by fixed drive frequency.

Like this, in the driving process, not necessarily must use the phase difference FEEDBACK CONTROL, also can fixed drive frequency.

In addition, Figure 37 represent can with the driving process P5 ' (second variation) of driving process P5 (Figure 29) displacement that illustrates in the 9th execution mode.In driving process P5 ', do not drive the phase difference feedback procedure S35 that process P5 is had, and generation carry out drive controlling (step S75) by fixed drive frequency.

Like this, even when carrying out phase difference counter-rotating detection, in the driving process, also not necessarily must use the phase difference FEEDBACK CONTROL, and can fixed drive frequency.

As mentioned above, when obtaining optimum phase difference with predetermined frequency, need pass through any means, time, number of starts and the number of times that carries out predetermined action are counted, but, also the value in the counter also can be remained in when non-drivings of piezo-activator this moment in the nonvolatile memory etc., thereby when starting piezo-activator once more, the value that count down in the way is increased count.Thus, need when piezo-activator starts, unconditionally not implement optimum phase difference and obtain process, carry out the driving of piezo-activator repeatedly with short span, when accumulative total driving time and number of times, also can implement obtaining reliably with predetermined frequency according to variable optimum phase difference such as state of wear.

In aforementioned each execution mode, the controller 65 of driving control device 50 is obtained each structure of unit, frequency control unit, phase difference counter-rotating detecting unit, clamper unit and memory cell and is constituted control unit by comprising frequency control unit, optimum phase difference, but, these each unit can be installed on respectively on the controller, also can constitute arbitrarily.Controller 65 not only can use hardware, also can realize by software.

In addition, controlled by the frequency control unit, implement the frequency that optimum phase difference is obtained process P1, in aforementioned each execution mode, be one hour, but the time that is set at frequency was not limited to one hour.Can be according to the size of the load of driven member etc., in the scope of for example a few minutes～several hrs, suitably determine.In addition, also can study to begin the long more then frequency of elapsed time from initial condition highly more, that is, make the less optimum phase difference of implementing of the time interval obtain process etc., can decide frequency according to the length in elapsed time.

In addition, implement the frequency that optimum phase difference is obtained process, also can determine by the factor beyond the time.That is, can be according to definite frequency such as number of starts of piezo-activator, for example making frequency is 255 startings, and is stored in the memory cell of controller.In addition, also can when being assemblied in electronic equipment, piezo-activator determine frequency.Also comprise the replacing of piezo-activator of the wearing and tearing etc. of the abutting part that is accompanied by vibrating body and driven member during this assembling.

The mode that frequency is determined can suitably be determined according to the load of driven member or the mode of operation of piezo-activator etc.Also can determine frequency according to the difference that aforementioned rotor just changes/reverses.

In addition, in first execution mode etc., optimum phase difference is defined as the driving efficient maximum that makes piezo-activator, but be not limited thereto, need not drive etc. under the situation with maximum drive efficient, can determine optimum phase difference, making it be fit to drive efficient is not maximum predetermined driving condition.

In addition, the phase difference detection unit 60 of aforementioned each execution mode has phase shifter 62 and phase comparator 63 etc., target setting phase difference θ in phase shifter 62, the control that reduces by the output that makes phase comparator 63, can be controlled to target phase difference, but be not limited thereto, as long as can be according to the phase place of target phase difference, detection signal and the phase place of drive signal, detect the deviation of the phase difference of detection signal and drive signal with respect to target phase difference, the structure of phase difference detection unit is arbitrarily.For example, at phase difference detection unit 60 (Fig. 4 etc.) is not hardware but under by situation about constituting to computer installation and control program, phase shifter 62 is not set and target phase difference θ is set in the phase comparator 63 in advance, and pass through phase comparator 63 and directly calculate phase difference, this phase difference and target phase difference θ are compared, and the detected phase difference is with respect to the deviation of target phase difference θ.

In the 5th execution mode, being example with Figure 16 is illustrated the vibration characteristics of vibrating body 20A, but be not limited to this situation shown in Figure 16, the gradient that also has the phase difference of optimal drive state is the situation of augment direction, under this situation, when from lower frequency side along ascent direction turntable driving frequency, phase difference reduces after target phase difference increases, and makes the part that reaches target phase difference become rollback point once more.That is, as long as the clamper frequency setting is become the value (comprising the phase difference reversal frequency) of optimal drive state side of the phase difference reversal frequency of this rollback point.

In addition, the scope of the frequency of scanning drive signal and direction are not limited to the 5th execution mode in first process.In the 5th execution mode, in initialize mode M1 from lower frequency side along ascent direction turntable driving frequency, but also can be from high frequency side along descent direction turntable driving frequency, and with the lower frequency side of clamper frequency setting in the frequency of optimal drive state G.The scope of scanning frequency also is not limited to the scope of 230～280kHz in the 5th execution mode, can suitably set according to desired driving condition.

In addition, in the 9th execution mode, illustrated in the timing of the switching of just changeing/reversing of rotor 30 and carried out the situation (S38) that optimum phase difference is obtained process P1 and phase difference counter-rotating testing process P4, but, this situation all is suitable for certainly for first execution mode and the 5th execution mode, when the switching of the vibrational state that so carries out vibrating body, obtain process and phase difference counter-rotating testing process by the optimum phase difference that constitutes the initial setting process, the different situation of drive characteristic in the time of can tackling positive direction and drive driven member in the other direction.That is, the driving amount of the driving amount in the time of can making forward drive (with flowing through the amount of movement of driven member or the electric current of vibrating body is represented) during with reverse drive is identical, and the control of predetermined difference etc. perhaps is set.

The invention is not restricted to the application in the electronic watch of aforementioned embodiments, also can be applicable to various electronic equipments, be specially adapted to require the portable electric appts of miniaturization.

Here, can list as various electronic equipments: phone, mobile phone, contactless IC card, PC, portable information terminal (PDA) and camera etc. with clocking capability.

In addition, also be applicable to the electronic equipment of camera, digital camera, the video camera with clocking capability, mobile phone etc. with camera function.When being applied to these electronic equipments, driver element of the present invention can be used to drive focusing or zoom mechanism, the aperture adjusting mechanism etc. of camera lens with camera function.

In addition, can use driving control device of the present invention for the driving mechanism of touchable toy classes such as the driving mechanism of the gauge pointer of the instrument board (instrumental panel) of the driving mechanism of the gauge pointer of measuring equipment or automobile etc., piezoelectric buzzer, the ink gun of printer, paper advance mechanism, the vehicles and the image of printer and attitude updating mechanism, supersonic motor etc.

In addition, in aforementioned each execution mode, piezo-activator 20 is used to drive the expression pointer constantly of electronic watch 1, but is not limited thereto, also piezo-activator of the present invention can be used to represent the driving of the mechanism in life week.

In addition, in aforementioned each execution mode, as the application examples of piezo-activator, example wrist-watch, but be not limited thereto, the present invention also is applicable to pocket-watch, desk clock, wall clock etc.At these various clock and watch, also can be as the mechanism that for example drives cuckoo clock etc.

In addition,, can adopt the rotor that is driven in rotation, the Linear Driving part of linear drives etc., not limit the driving direction of driven member as driven member.

Be used to realize optimum structure of the present invention, the method iseikonia is above-mentioned discloses like that, but the invention is not restricted to this.Promptly, the present invention mainly illustrates and illustrates specific execution mode, but in the scope that does not break away from technological thought of the present invention and purpose, can carry out various distortion to the shape in the above-mentioned execution mode, material, quantity and other detailed structure by this area professional.

Therefore the record that defines above-mentioned disclosed shape, material etc. is the exemplary record of carrying out in order to make easy to understand of the present invention, therefore be not limitation of the invention, the record of carrying out with the component names of part or all qualification of the qualification that has broken away from these shapes, material etc. is also contained in the present invention.

Claims (11)

1. the drive controlling method of a piezo-activator, the vibrating body that provides drive signal to vibrate by to piezoelectric element is provided this piezo-activator, and with described transfer of vibration to driven member, can detect simultaneously the vibrational state of described vibrating body, it is characterized in that this method comprises:

The initial setting process, this process has: the phase difference of detection signal of described drive signal and the described detected vibrational state of expression is implemented the frequency scanning of described drive signal, is that the optimum phase difference of optimum phase difference is obtained process to obtain the phase difference of realizing predetermined driving condition; And the phase difference that detects described drive signal and described detection signal, in the preset range that comprises the frequency that realizes described predetermined driving condition, implement simultaneously the frequency scanning of described drive signal, the phase difference of the phase difference reversal frequency when detecting described phase difference this moment and the reaching described optimum phase difference once more testing process of reversing towards predetermined direction; And

The driving process, this process limits the frequency of described drive signal, to avoid it to reach the clamper frequency of in the value of the described predetermined driving condition side of described phase difference reversal frequency, setting, and in the phase difference that detects described drive signal and described detection signal, according to described phase difference with respect to described optimum phase extent, make the frequency gets higher or the step-down of described drive signal, thereby make the frequency of described drive signal follow described phase difference

By carrying out described initial setting process, upgrade described optimum phase difference and described phase difference reversal frequency respectively with predetermined frequency.

2. the drive controlling method of piezo-activator according to claim 1 is characterized in that,

Described piezo-activator is loaded into and has timing portion and show in the time set of clocking information display part of the clocking information by the timing of described timing portion, driving described clocking information display part,

Described optimum phase difference is obtained process and is had the amount of movement recuperation, the position when this process makes the position of the described driven member that moves during implementing this optimum phase difference to obtain process turn back to this optimum phase difference to obtain process and begin,

In described driving process,,, control the amount of movement of this driven member according to the command value of sending from described timing portion according to the time of implementing during the described initial setting process.

3. the drive controlling method of piezo-activator according to claim 1 and 2 is characterized in that,

In described phase difference counter-rotating testing process, the value from described clamper frequency to described phase difference reversal frequency is stored in the memory cell.

4. according to the drive controlling method of each described piezo-activator in the claim 1 to 3, it is characterized in that,

The driving direction of described driven member can switch in positive direction with in the other direction,

Described initial setting process is carried out when the driving direction of described driven member is switched.

5. piezoelectric actuator drive control device, the vibrating body that provides drive signal to vibrate by to piezoelectric element is provided this device, and with described transfer of vibration to driven member, can detect simultaneously the vibrational state of described vibrating body, it is characterized in that this device comprises:

The initial setting unit, it has: the phase difference detection unit that detects the described drive signal and the phase difference of the detection signal of the described detected vibrational state of expression; Implement the frequency scanning of described drive signal, obtaining the phase difference of realizing predetermined driving condition according to the detection of the described phase difference that is undertaken by described phase difference detection unit is that the optimum phase difference of optimum phase difference is obtained the unit; And the phase difference that detects described drive signal and described detection signal, in the preset range that comprises the frequency that realizes described predetermined driving condition, implement simultaneously the frequency scanning of described drive signal, the phase difference of the phase difference reversal frequency when detecting described phase difference this moment and the reaching described optimum phase difference once more detecting unit that reverses towards predetermined direction;

Control unit, it sets the frequency of described drive signal according to described optimum phase difference; And

The frequency control unit, it upgrades described optimum phase difference and described phase difference reversal frequency respectively by carrying out the processing of described initial setting unit with predetermined frequency,

Described control unit has the clamper unit, it limits the frequency of described drive signal, to avoid it to reach the clamper frequency of in the value of the described predetermined driving condition side of described phase difference reversal frequency, setting, described control unit is implemented by the restriction of described clamper unit to the frequency of described drive signal, and when detecting described phase difference by described phase difference detection unit, according to described phase difference with respect to described optimum phase extent, make the frequency gets higher or the step-down of described drive signal, thereby make the frequency of described drive signal follow described phase difference.

6. piezoelectric actuator drive control device according to claim 5 is characterized in that,

Described control unit has the memory cell of storing in advance from described clamper frequency to the value of described phase difference reversal frequency.

7. according to claim 5 or 6 described piezoelectric actuator drive control device, it is characterized in that,

Described vibrating body vibrates with a plurality of vibration modes,

Described drive signal is single-phase.

8. piezoelectric actuator drive control device according to claim 7 is characterized in that,

It is rectangular-shaped that described vibrating body forms general plane,

Described a plurality of vibration mode is along the flexible extensional vibration of the length direction of described vibrating body with respect to the mixed mode of the flexural vibrations of described length direction bending.

9. according to each described piezoelectric actuator drive control device of claim 5 to 8, it is characterized in that,

The driving direction of described driven member can switch in positive direction with in the other direction,

Described initial setting unit uses when described vibrational state switches.

10. an electronic equipment is characterized in that, driven member and each described piezoelectric actuator drive control device of claim 5 to 9 that this electronic equipment has piezo-activator, driven by this piezo-activator.

11. electronic equipment according to claim 10 is characterized in that, described electronic equipment is to have timing portion and show clock and watch by the clocking information display part of the clocking information of described timing portion timing.

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