JP2007049887A - Piezoelectric vibrator, manufacturing method of same, piezoelectric actuator, and electronic equipment - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a piezoelectric vibrator capable of improving its reliability remarkably, by bonding a piezoelectric element and a reinforcement plate firmly. <P>SOLUTION: In the piezoelectric vibrating body 30 of a piezoelectric actuator, recessed portions 3311, which sink in the directions crossing the stacking direction of the piezoelectric elements 31, 32 and the reinforcement plate 33, are formed at the side surfaces of the reinforcement plate 33. This structure guides an adhesive AD, which is going to flow out of between piezoelectric elements 31, 32 and the reinforcement plate 33, and retains the adhesive AD inside the recessed portions 3311 when the piezoelectric elements 31, 32 and the reinforcement plate 33 are stacked and adhered, so that the spillover of the adhesive AD out of between the piezoelectric elements 31, 32 and the reinforcement plate 33 can be prevented. Therefore, the piezoelectric elements 31, 32 and the reinforcement plate 33 can firmly be adhered without lacking the adhesive AD between the piezoelectric elements 31, 32 and the reinforcement plate 33, and reliability can be obtained that can withstand the input of high power for driving a second chronograph hand continuously. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a piezoelectric vibrator, a method for manufacturing a piezoelectric vibrator, a piezoelectric actuator, and an electronic apparatus.

Since the piezoelectric element is excellent in conversion efficiency from electric energy to mechanical energy and responsiveness, a piezoelectric actuator that drives a driven body by vibration of a piezoelectric vibrating body having the piezoelectric element has been developed in recent years.
The structure of the piezoelectric vibrator used in the piezoelectric actuator is a piezoelectric element in which a reinforcing plate made of stainless steel or the like is laminated, and the laminated surfaces of these piezoelectric element and reinforcing plate are bonded together with an adhesive. (For example, Patent Document 1). These piezoelectric elements and the reinforcing plate are positioned relative to each other with pins or the like standing in the stacking direction when they are bonded.

Japanese Patent Laying-Open No. 2004-159403 (paragraph “0016” in the specification, FIG. 1)

Here, in manufacturing the piezoelectric vibrator, there is a problem that the adhesive easily flows out between the piezoelectric element and the reinforcing plate, and the piezoelectric element and the reinforcing plate cannot be sufficiently bonded. In particular, when the adhesive is cured in a high-temperature atmosphere, the fluidity of the adhesive increases as the temperature rises, so that it is more likely to flow out.
In addition, in the portion where the positioning pin abuts, the outflow of the adhesive is promoted by the capillary phenomenon in the slight gap between the piezoelectric element and the reinforcing plate and the pin. There is a possibility that a gap is left between the piezoelectric element and the piezoelectric element and the reinforcing plate are peeled off during vibration. That is, there is a problem that reliability is lowered due to the outflow of the adhesive from the bonding surface between the piezoelectric element and the reinforcing plate.
In addition, since the adhesive that has flowed out from the bonding surface of the piezoelectric element and the reinforcing plate is fixed to the pin at the portion where the pin comes into contact, the piezoelectric element and the reinforcing plate are peeled off when removed from the pin. Becomes worse. In addition, it takes time to remove the adhesive adhered to the pins, and the productivity has been reduced.

  In view of such problems, an object of the present invention is to provide a piezoelectric vibrator capable of greatly improving the reliability by firmly bonding the piezoelectric element and the reinforcing plate, a method for manufacturing the piezoelectric vibrator, and a piezoelectric vibrator. An object of the present invention is to provide a piezoelectric actuator and an electronic device that are provided.

  The piezoelectric vibrating body of the present invention is a piezoelectric vibrating body that includes a piezoelectric element provided with an electrode and a reinforcing member laminated with the piezoelectric element, and vibrates when a voltage is applied to the electrode. The laminated surfaces of the reinforcing members that are stacked and laminated are bonded to each other with an adhesive, and the outer peripheral surface of the reinforcing member is a recess that is recessed in a direction that intersects with the lamination direction of the reinforcing member and the piezoelectric element. Is formed.

According to this invention, since the concave portion that is recessed in the direction intersecting the stacking direction is formed on the outer peripheral surface of the reinforcing member, when the piezoelectric element and the reinforcing member are stacked and bonded, the piezoelectric element and the reinforcing member The adhesive that is about to flow out of the gap is guided to the recess, and the adhesive can be retained in the recess. As a result, even when the adhesive is cured in a high temperature atmosphere from the viewpoint of productivity, or when the positioning pin is brought into contact with the piezoelectric element and the reinforcing member, the adhesive is held by the surface tension in the recess, It is possible to prevent the adhesive from flowing out between the piezoelectric element and the reinforcing member.
Therefore, the piezoelectric element and the reinforcing member can be firmly bonded without a shortage of the adhesive between the piezoelectric element and the reinforcing member, and reliability that can withstand high power can be realized.
In particular, when the power is turned on, heat generation of the piezoelectric element due to voltage application and heat generation due to friction between the driven body and the reinforcing member become a problem, but because the surface area of the reinforcing member is enlarged in the recessed portion, Can contribute to heat dissipation. Thereby, peeling of the piezoelectric element and the reinforcing member due to deterioration of the adhesive exceeding the limit temperature can be prevented.
On the other hand, by preventing the adhesive from flowing out, the adhesive does not adhere between the piezoelectric element and the reinforcing member and the positioning pin, so that the piezoelectric element and the reinforcing member can be prevented from being detached when removed from the bonding jig, thereby improving the yield. It can also lead to cost reduction.

In the piezoelectric vibrating body of the present invention, the area of the laminated surface of the reinforcing member is larger than the area of the laminated surface of the piezoelectric element, and when the reinforcing member is laminated with the piezoelectric element, It is preferable to protrude from the outer periphery.
According to the present invention, the adhesive that is about to flow out from between the reinforcing member and the piezoelectric element is held by the surface tension at the portion of the reinforcing member that protrudes toward the outer peripheral side of the piezoelectric element, that is, the aforementioned concave portion and the protruding portion. Thus, it is possible to prevent the adhesive from flowing out, so that the piezoelectric element and the reinforcing member can be bonded more firmly, and the reliability can be further improved.
Further, since the reinforcing member protrudes from the outer periphery of the piezoelectric element, the surface area is large, and heat generated in the vibrating body during driving is dissipated from the protruding portion, so that the adhesive can be prevented from being deteriorated due to temperature rise. That is, it is suitable for high power application.

In the piezoelectric vibrating body of the present invention, the piezoelectric element and the reinforcing member are formed in a plate shape, and surfaces along the plane direction thereof are overlapped, and the concave portion is a groove that is continuous along the side surface of the reinforcing member. It is preferable to extend in a shape.
According to the present invention, since the concave portion is formed on the side surface intersecting the laminated surface in the plate-shaped reinforcing member, the adhesive overflowing from the laminated surface of the reinforcing member and the piezoelectric element is quickly and surely guided to the concave portion. And reliability can be further improved.
In addition, the cross-sectional shape of a recessed part can employ | adopt arbitrary things, such as circular arc shape and U shape.

  In the piezoelectric vibrating body of the present invention, it is preferable that at least one corner portion of the piezoelectric element has a chamfered portion that forms the corner portion into a chamfered shape.

According to this invention, most of the peeling force applied to the corner portion (corner portion where the chamfered portion is formed) of the piezoelectric element is applied to the chamfered portion. Since the peeling force is not concentrated on the tip of the corner of the element, the piezoelectric element and the reinforcing member can be prevented from peeling from the corner of the piezoelectric element.
In addition, since the piezoelectric element is chamfered in this manner, the exposed area of the reinforcing member increases. Since the reinforcing member is often made of metal and has a high thermal conductivity, the exposed area of the reinforcing member is thus large, when the adhesive is cured and when placed in a high-temperature atmosphere. The temperature rise of the reinforcing member becomes faster and the temperature distribution becomes uniform.
For this reason, the temperature rise of the adhesive between the reinforcing member and the piezoelectric element is also accelerated, and the curing of the adhesive is promoted. This shortens the time during which the adhesive flows out during curing, reduces the residual stress after curing, and improves the reliability of bonding. Further, the exposed area of the reinforcing member is increased by chamfering the piezoelectric element, so that heat dissipation during use is promoted. Thereby, the temperature rise of an adhesive agent is suppressed and peeling can be prevented more reliably.
That is, in addition to forming the concave portion on the side surface of the reinforcing plate and chamfering the corner portion of the piezoelectric element in this way, the effect of preventing peeling can be synergistically enhanced.

In the piezoelectric vibrating body of the present invention, it is preferable that the chamfered portion of the piezoelectric element has a contoured line.
According to this invention, since the contour line of the chamfered portion is formed in a curved shape, the contour line can be made longer than in the case of forming it in a linear shape. Here, if the contour line of the chamfered portion is lengthened, the chamfered portion itself becomes larger, and the peeling force is distributed according to the size of the chamfered portion, so that the piezoelectric element and the reinforcing member do not easily peel off. Can do.

  The method for manufacturing a piezoelectric vibrating body according to the present invention is a method for manufacturing a piezoelectric vibrating body having a piezoelectric element provided with an electrode and a reinforcing member laminated with the piezoelectric element, and vibrating when a voltage is applied to the electrode. The piezoelectric element and the reinforcing member are abutted and positioned on a pin extending in the stacking direction of the piezoelectric element and the reinforcing member, and the piezoelectric element and the reinforcing member are bonded to each other with an adhesive, The piezoelectric element and the reinforcing member are pressurized along the stacking direction.

  According to the present invention, when the piezoelectric element and the reinforcing member are bonded, positioning is performed by the pin, so that the piezoelectric element and the reinforcing member are accurately bonded to each other, and variation in vibration characteristics can be prevented, and in the stacking direction. Since the piezoelectric element and the reinforcing member are more firmly bonded by pressurizing along, the reliability can be further ensured.

  In the piezoelectric vibrating body manufacturing method of the present invention, a step is provided in the axial direction of the pin, and the area of the laminated surface of the reinforcing member laminated with the piezoelectric element is laminated with the reinforcing member of the piezoelectric element. The reinforcing member is laminated with the piezoelectric element such that the laminated surface of the reinforcing member extends outside the laminated surface of the piezoelectric element, and the step of the pin is It is preferable to contact the stepped side.

  According to the present invention, the piezoelectric element and the reinforcing member are positioned with the step provided by the pin provided with the step, so that the piezoelectric element and the reinforcing member can be bonded together more accurately.

The piezoelectric actuator of the present invention includes the above-described piezoelectric vibrator or the piezoelectric vibrator manufactured by the above-described manufacturing method, and a driven body driven by the vibration of the piezoelectric vibrator.
According to the present invention, since the piezoelectric vibrator described above is provided, the same operations and effects as described above can be obtained.
Here, the piezoelectric actuator can be used for, for example, a zoom mechanism and an autofocus mechanism of a camera, an inkjet head and a paper feed mechanism of a printer, a piezoelectric buzzer, an ultrasonic motor that drives a movable toy, and the like.

An electronic apparatus according to the present invention includes the piezoelectric actuator described above.
According to the present invention, since the piezoelectric actuator described above is provided, the same operations and effects as described above can be enjoyed.

The electronic apparatus according to the present invention is preferably a timepiece including a time measuring means and a time information display unit for displaying information timed by the time measuring means.
According to the present invention, it is possible to drive the gears constituting the time measuring means and the time information display unit with the piezoelectric actuator described above. As mentioned above, since the piezoelectric actuator can withstand high power input, it can drive time indication hands such as hours, minutes, seconds, etc. that are continuously driven compared to displaying calendars such as dates. Is also possible. Moreover, a pointer or a rotating plate having a thickness that becomes a high load can be used as a driven body, and a design with a profound feeling can be achieved.
In addition, the advantage of the piezoelectric actuator, that is, it is not affected by magnetism, has high responsiveness, can be finely fed, is advantageous for downsizing and thinning, and can realize high torque.

  According to the present invention, since the piezoelectric element and the reinforcing member are firmly bonded and heat dissipation is also achieved, peeling of the piezoelectric element and the reinforcing member during driving can be prevented and reliability can be greatly improved. The yield can be improved and the cost can be reduced.

[First Embodiment]
Hereinafter, a first embodiment of the present invention will be described with reference to the drawings.
In the description of the second and subsequent embodiments, the same components as those of the first embodiment described below are denoted by the same reference numerals, and description thereof is omitted or simplified.

(1. Schematic configuration of the watch)
FIG. 1 is a plan view showing an electronic timepiece 10 according to the present embodiment. The electronic timepiece 10 includes a movement 1 as a timekeeping means, a dial 2, a hour hand 3, a minute hand 4, a second hand 5 as a time information display unit for displaying a normal time, and a second chronograph hand indicating a chronograph time. 6. A minute chronograph hand 7 is provided.
The hour hand 3, the minute hand 4, and the second hand 5 are the same as ordinary analog quartz, and are a circuit board in which a crystal unit is incorporated, a stepping motor having a coil, a stator and a rotor, a driving wheel train, a battery And driven by.

(2. Second chronograph hand drive mechanism)
FIG. 2 shows a drive mechanism for driving the second chronograph hand 6 (FIG. 1).
The driving mechanism of the second chronograph hand 6 includes a piezoelectric actuator 20 and a speed reducing wheel train 50 that transmits the driving force of the piezoelectric actuator 20 to the second chronograph hand 6.
The piezoelectric actuator 20 includes a piezoelectric vibrating body 30 having a piezoelectric element and a rotor 40 that rotates by vibration of the piezoelectric vibrating body 30. The piezoelectric vibrating body 30 will be described later.
The rotor 40 is biased by the leaf spring 41 toward the piezoelectric vibrating body 30, and an appropriate frictional force is generated between the piezoelectric vibrating body 30 and the outer periphery of the rotor 40, so that the vibration of the piezoelectric vibrating body 30 is efficient. It is well transmitted to the rotor 40.
The reduction gear train 50 is arranged coaxially with the rotor 40 and rotates integrally with the rotor 40, meshes with the gear 51, and is fixed to the rotation shaft of the second chronograph hand 6 (FIG. 1). In these gears 51, 52, the rotation of the rotor 40 is decelerated and transmitted.

(3. Structure of vibrating body of piezoelectric actuator)
Next, the most characteristic structure of the piezoelectric vibrating body 30 in this embodiment will be described.
FIG. 3 is a perspective view of the piezoelectric vibrating body 30.
The piezoelectric vibrating body 30 includes two piezoelectric elements 31 and 32 having a rectangular shape, and a reinforcing plate 33 as a reinforcing member interposed between the piezoelectric elements 31 and 32.

The materials of the piezoelectric elements 31 and 32 are not particularly limited, and lead zirconate titanate (PZT (registered trademark)), crystal, lithium niobate, barium titanate, lead titanate, lead metaniobate, polyvinylidene fluoride, zinc Various materials such as lead niobate and lead scandium niobate can be used.
Electrodes 310 and 320 for applying drive signals to the piezoelectric elements 31 and 32 are formed on the surfaces of the piezoelectric elements 31 and 32 by plating, sputtering, vapor deposition, or the like using nickel or gold, respectively. Although not shown in the drawings, the same electrodes as those on the front surface side are formed on the back surfaces of the piezoelectric elements 31 and 32, and these electrodes are overlapped with the reinforcing plate 33 and are electrically connected.

  The reinforcing plate 33 is formed of stainless steel or other conductive metal material, and protrudes in a circular arc shape from a rectangular main body 331 to which the piezoelectric elements 31 and 32 are bonded, and from both side surfaces on the short side of the main body 331. The protrusions 332 and 333 and the arm portion 334 protruding in the width direction of the main body 331 from one side surface of the main body 331 are integrally provided.

Further, the reinforcing plate 33 is provided with a concave portion 3311 having an arcuate cross section extending in a groove shape along the outer periphery of the side surface.
The recess 3311 is formed by etching on both the front and back surfaces of the metal plate when the reinforcing plate 33 is manufactured from the metal plate. That is, the reinforcing plate 33 is removed from the metal plate by the etching. It is formed. The recess 3311 is formed continuously over substantially the entire circumference of the four sides of the reinforcing plate 33.
The recess 3311 can also be formed by means other than etching, such as cutting and polishing the outer periphery of the side surface of the reinforcing plate 33 formed by wire cutting or press punching of a metal plate.

The protrusions 332 and 333 are formed at diagonal positions of the main body 331, and one protrusion 332 contacts the rotor 40.
A hole 334 </ b> A is formed in the arm portion 334, and the piezoelectric vibrating body 30 is fixed to a ground plate constituting the movement 1 by inserting a screw 334 </ b> B (FIG. 2) through the hole 334 </ b> A.

(4. Method for assembling piezoelectric vibrator)
Next, assembly (manufacture) of the piezoelectric vibrating body 30 will be described.
4 is a plan view of the piezoelectric vibrating body 30 in the assembling process, and FIG. 5 is a side sectional view of the piezoelectric vibrating body 30 in the same assembling process.
When the piezoelectric vibrating body 30 is assembled, an adhesive jig 60 in which cylindrical pins 61A, 61B, 61C are erected on the base 61 is used.

First, the piezoelectric element 32 is disposed on the base 61. As shown in FIG. 5, the adhesive element AD (FIG. 5) such as a thermosetting epoxy resin is applied to the surface of the piezoelectric element 32, and then the piezoelectric element 32 is applied. The reinforcing plate 33 is overlaid on. Further, after the adhesive AD is applied to the reinforcing plate 33, the piezoelectric element 31 is overlaid on the reinforcing plate 33.
At this time, as shown in FIG. 4, the pins 61A are brought into contact with the side surfaces on the short side of the piezoelectric elements 31 and 32 and the reinforcing plate 33, and the pins 61B and 61C are brought into contact with the side surfaces on the long side. The piezoelectric elements 31 and 32 and the reinforcing plate 33 are positioned in the in-plane direction of the plate surface.

After that, as shown in FIG. 5, a plate-like pressure plate 62 is stacked on the piezoelectric element 31, and the piezoelectric element 31 sandwiched between the pressure plate 62 and the base 61 by an arbitrary pressure means (not shown). , 32 and the reinforcing plate 33 are pressurized. In this embodiment, in parallel with this pressurization, hot air, a hot beam, or the like is used to cure the adhesive AD in a high temperature atmosphere.
In this process, the fluidity of the adhesive AD is increased by high temperature and is pressed, so that the piezoelectric element 31 and the reinforcing plate 33 are bonded to each other, the laminated surfaces 311 and 331A, and the reinforcing plate 33. The adhesive AD easily overflows outside the laminated surfaces 331B and 321 bonded to the piezoelectric element 32, but the overflowed adhesive AD is recessed through the edge portions 331C and 331D of the laminated surfaces 331A and 331B of the reinforcing plate 33. Guided by 3311 and held in the recess 3311 by the surface tension in the recess 3311.

For this reason, between the piezoelectric elements 31 and 32 and the pins 61A to 61C, or between the reinforcing plate 33 and the pins 61A to 61C, in the portion where the piezoelectric elements 31 and 32 and the pins 61A to 61C of the reinforcing plate 33 are in contact with each other. The adhesive AD does not flow into the slight gap between the laminated surfaces 311 and 331A of the piezoelectric element 31 and the reinforcing plate 33, and the laminated surfaces 331B of the reinforcing plate 33 and the piezoelectric element 32. Adhesive AD between 321 is not insufficient. Therefore, the piezoelectric elements 31 and 32 and the reinforcing plate 33 are firmly bonded to complete the piezoelectric vibrating body 30.
Since the adhesive AD is prevented from flowing out, the adhesive AD does not adhere between the piezoelectric elements 31 and 32 and the pins 61A to 61C or between the reinforcing plate 33 and the pins 61A to 61C. It is possible to prevent the piezoelectric elements 31 and 32 and the reinforcing plate 33 from being detached or damaged when the body 30 is removed from the bonding jig 60.

(5. Operation of piezoelectric actuator)
The piezoelectric vibrating body 30 of the piezoelectric actuator 20 described above excites longitudinal primary vibration that expands and contracts in the longitudinal direction by applying an alternating voltage of a predetermined frequency to the piezoelectric elements 31 and 32, and both ends of the piezoelectric vibrating body 30 in the width direction. Since the projections 332 and 333 are respectively provided on the first and second projections, the bending secondary vibration is also excited in the direction intersecting the longitudinal direction. By combining the longitudinal vibration and the bending vibration in this way, the protrusion 332 draws a locus R (FIG. 2) that approximates an ellipse, and the rotor 40 is repeatedly pressed against the protrusion 332 by a part of the locus R and rotates. The protrusion 333 that is not in contact with the rotor 40 functions as a balancer at the point-symmetrical position of the protrusion 332, so that the movement locus of the protrusion 332 becomes a desired locus R.
As the rotor 40 rotates, the gear 51 integrated with the rotor 40 also rotates. As the gear 51 rotates, the gear 52 rotates. As the gear 52 rotates, the second chronograph hand 6 is fed.

(6. Effects of the present embodiment)
According to this embodiment described above, the following effects can be obtained.
(1) In the piezoelectric vibrating body 30 of the piezoelectric actuator 20, since the concave portion 3311 is formed on the side surface of the reinforcing plate 33 so as to intersect with the stacking direction of the piezoelectric elements 31 and 32. When the reinforcing plate 33 is laminated and bonded, the adhesive AD that tends to flow out between the piezoelectric elements 31 and 32 and the reinforcing plate 33 can be guided to the recess 3311, and the adhesive AD is held in the recess 3311. The outflow of the adhesive AD from between the piezoelectric elements 31 and 32 and the reinforcing plate 33 can be prevented.
Accordingly, the piezoelectric elements 31 and 32 and the reinforcing plate 33 can be firmly bonded without running out of the adhesive AD between the piezoelectric elements 31 and 32 and the reinforcing plate 33, and the second chronograph hand 6 is continuously driven. It is possible to achieve reliability that can withstand high power input.

(2) Further, since the adhesive AD is prevented from flowing out between the piezoelectric elements 31 and 32 and the reinforcing plate 33, the gap between the piezoelectric elements 31 and 32 and the positioning pins 61 </ b> A to 61 </ b> C and the reinforcing plate 33 are positioned. Since the adhesive AD does not adhere in the gaps with the pins 61A to 61C, the piezoelectric elements 31, 32 and the reinforcing plate 33 can be prevented from peeling when removed from the bonding jig 60, and the yield can be improved, leading to cost reduction. be able to.

(3) Further, particularly when high power is applied to the piezoelectric vibrating body 30, heat generation of the piezoelectric elements 31 and 32 and heat generation due to friction between the rotor 40 and the protrusion 332 become a problem. Since the surface area of 33 is enlarged, it can contribute to heat dissipation. Thereby, peeling with the piezoelectric elements 31 and 32 and the reinforcement board 33 by deterioration of adhesive agent AD can be prevented.

(4) The piezoelectric elements 31 and 32 and the reinforcing plate 33 are formed in a plate shape, and on the side of the reinforcing plate 33 adjacent to the laminated surfaces 331A and 331B of the piezoelectric elements 31 and 32 and the reinforcing plate 33 via the edge portions 331C and 331D. Since the concave portion 3311 is formed, the adhesive surfaces AD that overflow from the laminated surfaces 311 and 331A of the piezoelectric element 31 and the reinforcing plate 33 and the laminated surfaces 331B and 321 of the reinforcing plate 33 and the piezoelectric element 32 can be quickly and reliably obtained. It is possible to guide to the recess 3311, and the reliability can be further improved.

(5) When the piezoelectric vibrating body 30 is assembled, the piezoelectric elements 31 and 32 and the reinforcing plate 33 are positioned by the pins 61A to 61C. Variations in vibration characteristics in the body 30 can be prevented. In addition, since the piezoelectric elements 31 and 32 and the reinforcing plate 33 are more firmly bonded by applying pressure along the stacking direction of the piezoelectric elements 31 and 32 and the reinforcing plate 33, the reliability can be further ensured. .

(6) Since the piezoelectric actuator 20 can withstand high power input, it is possible to drive the second chronograph hand 6 that is continuously driven as compared with the case of displaying a calendar such as date. In addition, since the second chronograph hand 6 to be driven can be driven even if it is thick, the electronic timepiece 10 can be made heavy and have a high-class design.

[Second Embodiment]
Next, a second embodiment of the present invention will be described.
In the present embodiment, the planar dimension of the reinforcing plate included in the piezoelectric vibrating body of the piezoelectric actuator is larger than that of the reinforcing plate 33 in the first embodiment.

FIG. 6 is a plan view of the piezoelectric vibrating body 70 in the present embodiment, and FIG. 7 is a side sectional view of the vibrating body 70.
In the reinforcing plate 73 of the vibrating body 70, the vertical and horizontal dimensions of the rectangular main body 731 on which the piezoelectric elements 31 and 32 are arranged are each slightly larger than the same dimensions of the piezoelectric elements 31 and 32. That is, the area of the main body 731 is piezoelectric. Since it is larger than the area of the elements 31 and 32, the main body 731 protrudes from the four sides of the piezoelectric elements 31 and 32.
The piezoelectric vibrator 70 and the rotor 40 (FIG. 2) are provided to form a piezoelectric actuator, and the second chronograph hand 6 (FIG. 1) is moved by this piezoelectric actuator as in the first embodiment. .

When assembling the vibrating body 70, as described above, the adhesive AD between the piezoelectric elements 31, 32 and the reinforcing plate 73 is cured by pressurization and heating after positioning. In this embodiment, As shown in FIG. 7, a stepped pin 81 is used in which a large diameter portion 812 is arranged on both upper and lower sides across a small diameter portion 811. That is, as the reinforcing plate 73 protrudes from the piezoelectric elements 31 and 32, the pin 81 is constricted at the center portion to form a small diameter portion 811.
For this reason, when the piezoelectric elements 31 and 32 are stacked on both the front and back surfaces of the reinforcing plate 73, the piezoelectric elements 31 and 32 come into contact with the large diameter portion 812 of the pin 81, and the reinforcing plate 73 contacts the small diameter portion 811. Abutted.
In addition, the pin 81 is arrange | positioned at the short side and long side of the vibrating body 70 respectively like the pins 61A-61C in 1st Embodiment.

  Here, the reinforcing plate 73 protrudes from the four sides of the piezoelectric elements 31 and 32, that is, the laminated surfaces 731 A and 731 B laminated with the piezoelectric elements 31 and 32 of the reinforcing plate 73 are bonded to the reinforcing plate 73 of the piezoelectric elements 31 and 32. Since the adhesive AD is held by the surface tension on the laminated surfaces 731A and 731B of the reinforcing plate 73, the adhesive AD is held between the piezoelectric elements 31 and 32 and the reinforcing plate 73. The outflow of the adhesive AD is suppressed.

  On the other hand, when the vibrating body 70 is driven by applying a voltage to the piezoelectric elements 31 and 32, the reinforcing plate 73 is made of metal and has good thermal conductivity, and the surface area of the reinforcing plate 73 is the first embodiment. Since it is enlarged compared with the form, heat dissipation of the reinforcing plate 73 is promoted, and the adhesive AD between the piezoelectric elements 31 and 32 and the reinforcing plate 73 is unlikely to become high temperature. As a result, the adhesive AD does not deteriorate or deteriorate beyond the limit temperature, and peeling between the reinforcing plate 73 and the piezoelectric elements 31 and 32 can be prevented.

According to the present embodiment described above, the following effects can be obtained in addition to the effects described in the first embodiment.
(7) Since the area of the reinforcing plate 73 is larger than the area of the piezoelectric elements 31 and 32 and the reinforcing plate 73 protrudes from the outer periphery of the piezoelectric elements 31 and 32 at the time of stacking, the stacked surface of the protruding portions with the piezoelectric elements 31 and 32 The adhesive AD is held by 731A and 731B, that is, it is possible to prevent the adhesive AD from flowing out by both the concave portion 3311 of the reinforcing plate 73 and the laminated surfaces 731A and 731B. For this reason, the piezoelectric elements 31 and 32 and the reinforcing plate 73 can be bonded more firmly than in the first embodiment.
Further, since the reinforcing plate 73 has a large surface area and heat dissipation of the vibrating body 70 is promoted, it is possible to prevent the adhesive AD from being deteriorated due to a temperature rise.

(8) Furthermore, when the vibrating body 70 is driven, the piezoelectric elements 31 and 32 generate heat when voltage is continuously applied thereto, and also generate heat due to friction between the protrusion 332 and the rotor 40. , 32 and the reinforcing plate 73 are likely to have a high temperature, but since the heat dissipation is promoted by the reinforcing plate 73 as described above, problems such as peeling of the piezoelectric elements 31, 32 and the reinforcing plate 73 occur. Absent. Therefore, the vibrating body 70 has a feed amount per unit time larger than that of the indication member indicating the calendar such as the date and time (for example, the hour hand 3 and the minute hand 4) and is moved substantially continuously. It is suitable for high power applications for driving the graph hand 6 and the like.

(9) When the vibrating body 70 is assembled, the piezoelectric elements 31 and 32 and the reinforcing plate 73 are positioned by the large diameter portion 812 and the small diameter portion 811 of the pin 81, respectively. 73 can be bonded more accurately.

[Third Embodiment]
Next, a third embodiment of the present invention will be described. The piezoelectric vibrating body in the present embodiment is generally a chamfered corner of a piezoelectric element in the piezoelectric vibrating body 70 (FIG. 6) in the second embodiment.
FIG. 8 is a plan view of the piezoelectric vibrating body 90 of the present embodiment. The piezoelectric vibrating body 90 is configured by laminating piezoelectric elements 91 on both the front and back surfaces of the reinforcing plate 73. The reinforcing plate 73 can be replaced with the reinforcing plate 33 (FIG. 3) of the first embodiment.

  As shown in FIG. 8, in the planar shape of the piezoelectric element 91, the outer periphery is mainly constituted by four linear outer peripheries 91A, 91B, 91C, 91D. Here, in the four outer peripheries 91A to 91D, two opposing outer peripheries (for example, 91A and 91C) are formed in parallel to each other, and two adjacent outer peripheries (for example, 91A and 91B) are formed to be perpendicular to each other. A substantially rectangular planar shape is formed by the outer periphery including these four outer peripheries 91A to 91D. Hereinafter, the formation direction of the outer periphery 91A and the outer periphery 91C is referred to as a length direction, and the formation direction of the outer periphery 91B and the outer periphery 91D is referred to as a width direction, and the description may be simplified.

  More specifically, each corner is formed in a chamfered shape at two corners (lower left corner and upper right corner in FIG. 8) that are diagonally related to each other in the substantially rectangular shape of the piezoelectric element 91 in plan view. Chamfered portions 911 and 912 are formed. More specifically, a chamfered portion 911 is formed at a corner portion constituted by the outer periphery 91A and the outer periphery 91B, and a chamfered portion 912 is formed at a corner portion constituted by the outer periphery 91C and the outer periphery 91D. The piezoelectric element 91 can be formed by various forming methods. For example, a piezoelectric element 91 having chamfered portions 911 and 912 can be formed by forming a piezoelectric element plate having a rectangular shape in plan view and then scraping off sharp corners of the piezoelectric element plate. The piezoelectric element 91 in which the chamfered portions 911 and 912 are formed at the corners can also be formed.

  As described above, the outer periphery of the planar shape of the piezoelectric element 91 is constituted by the four outer peripheries 91A to 91D and the two chamfered portions 911 and 912. Here, the planar shape of the piezoelectric element 91 is point-symmetric with respect to the center point O in the planar shape. Therefore, the chamfered portion 911 and the chamfered portion 912 have the same shape. Therefore, in the following description, the chamfered portion 911 will be mainly described, and the description of the chamfered portion 912 will be omitted as appropriate. In addition, it is natural that almost all of the description given for the chamfered portion 911 applies to the chamfered portion 912.

  As shown in FIG. 8, the contour line of the chamfered portion 911 is formed in a smooth curved shape, inside the right angle formed by the extension line 91A ′ of the outer periphery 91A and the extension line 91B ′ of the outer periphery 91B. The outer peripheries 91A and 91B are connected to each other. The contour line of the chamfered portion 911 is smoothly connected to the outer periphery 91A and the outer periphery 91B at both ends 9111 and 9112, so that no pointed portion is generated at each connection portion. Further, the contour line of the chamfered portion 911 has a minimum curvature at the end 9111 connected to the outer periphery 91A, gradually increases in curvature, and maximizes the curvature at the end 9112 connected to the outer periphery 91B. It has become. Thus, in the chamfered portion 911, the length L along the formation direction of the outer periphery 91A (left and right direction in FIG. 8) is larger than the width B along the formation direction of the outer periphery 91B (up and down direction in FIG. 8). And L> B is established.

  Here, the relationship between the protrusion 332 and the piezoelectric element 91 will be described. The protrusion 332 extends along the same protruding direction as the forming direction of one outer periphery 91A constituting the corner (left and right in FIG. 8) at the corner of the piezoelectric element 91 where the chamfered portion 911 is formed. The protrusion is formed. Thus, since the chamfered portion 911 of the piezoelectric element 91 and the protrusion 332 of the reinforcing plate 73 are adjacent to each other, the chamfered portion 911 is formed at the corner of the piezoelectric element 91 closest to the protrusion 332 of the reinforcing plate 73. Will be. The protrusion 332 is formed so as to contact the outer periphery 91A. The protrusion 332 has a width b along a width direction (vertical direction in FIG. 8) perpendicular to the protrusion direction of the protrusion 332. As described above, the protrusion 332 is in contact with the rotor 40 (FIG. 3), and can rotate the rotor 40 according to the expansion and contraction of the piezoelectric element 91.

  Looking at the relationship between the chamfered portion 911 of the piezoelectric element 91 and the protrusion 332 of the reinforcing plate 73, the width B of the chamfered portion 911 is smaller than the width b of the protrusion 332 and larger than 1/50 of the width b. 0.02 × b <B <b is established. Here, when B <b is satisfied, as shown in FIG. 8, a part of the other outer periphery 91B constituting the corner portion of the piezoelectric element 91 in which the chamfered portion 911 is formed is formed in the thickness direction. It overlaps with the protrusion 332 along. Further, the protrusion 332 extends outward from the chamfered portion 911.

  In the piezoelectric vibrating body 90 configured as described above, since the reinforcing plate 73 is exposed from the chamfered portions 911 and 912, the reinforcing plate made of metal in a high temperature atmosphere in the bonding process between the piezoelectric element 91 and the reinforcing plate 73. The temperature of the exposed portion of 73 increases quickly, and the temperature of the adhesive AD between the piezoelectric element 91 and the reinforcing plate 73 also increases as the temperature of the entire reinforcing plate 73 increases. As a result, the curing time of the adhesive AD is shortened, and the adhesive AD guided in the recess 3311 is reliably cured in the recess 3311.

  Next, the experimental result about the drive performance of the piezoelectric vibrating body 90 in this embodiment is shown. The graph of FIG. 9 shows the rotational speed (rps) of the rotor with respect to the driving distance (m) during continuous driving. Here, as indicated by a broken line in the graph, in the case of a piezoelectric vibrating body in which neither the concave portion 3311 of the reinforcing plate nor the chamfered portions 911 and 912 of the piezoelectric element is formed, the rotor 40 rotates due to peeling or the like. The driving distance when stopped was 3375 m. On the other hand, in the piezoelectric vibrating body 90 of the present embodiment indicated by a solid line, the driving distance at which the rotation of the rotor 40 stopped reached 10367 m. That is, it can be seen that the drivable distance extends to about three times by the formation of the recess 3311 in the reinforcing plate 73 and the chamfered portions 911 and 912 in the piezoelectric element 91. It can be concluded that this is because the formation of the concave portion 3311 and the chamfered portions 911 and 912 does not cause poor adhesion and the reliability is improved. In addition, the promotion of heat dissipation during continuous driving through the reinforcing plate 73 exposed from the chamfered portions 911 and 912 can also contribute to the extension of the drivable time.

According to the present embodiment described above, the following effects are obtained in addition to the effects described in the second embodiment.
(10) Most of the peeling force applied to the corners of the piezoelectric element 91 (the corners where the chamfered portions 911 and 912 are formed) is applied to the chamfered portions 911 and 912. As described above, since the peeling force is not concentrated on the tip of the corner of the piezoelectric element 91, it is possible to prevent the piezoelectric element 91 and the reinforcing plate 73 from peeling from the corner of the piezoelectric element 91. Can do.

(11) In addition, since the piezoelectric element 91 is chamfered in this way, the exposed area of the reinforcing plate 73 is increased. Therefore, when the adhesive is cured, when the adhesive plate is placed in a high temperature atmosphere, The temperature rises faster and the temperature distribution becomes uniform. For this reason, the temperature rise of the adhesive AD between the reinforcing plate 73 and the piezoelectric element 91 is also accelerated, and the curing of the adhesive AD is promoted. As a result, the time during which the adhesive AD flows out during curing is shortened, the residual stress after curing is reduced, and the adhesion reliability is improved.
Furthermore, since the exposed area of the reinforcing plate 73 is increased by the chamfered portions 911 and 912 of the piezoelectric element 91, heat dissipation during use is promoted. Thereby, the temperature rise of adhesive agent AD is suppressed and peeling can be prevented more reliably.
In other words, the synergistic effect of forming the concave portion 3311 on the outer peripheral surface of the reinforcing plate 73 and forming the chamfered portions 911 and 912 at the corners of the piezoelectric element 91 in this way extends the drivable distance by about three times. As shown (see FIG. 9), the effect of preventing peeling can be dramatically improved.

  In addition, the piezoelectric vibrating body in which neither the concave portion of the reinforcing plate nor the chamfered portion of the piezoelectric element is formed, and the piezoelectric vibrating body in which the concave portion 3311 (FIG. 5) is not formed and only the chamfered portions 911, 912 are formed. In comparison with the above, the driveable distance can be approximately doubled by forming the chamfered portions 911 and 912.

(12) Furthermore, since the contour lines of the chamfered portions 911 and 912 of the piezoelectric element 91 are formed in a curved shape (so-called R shape), compared to the case where the chamfered portions 911 and 912 are formed linearly. (So-called C cut), the contour line can be lengthened. That is, the contour lines of the chamfered portions 911 and 912 are smoothly connected to the outer periphery 91A and the outer periphery 91B at both ends 9111 and 9112 so that no pointed portion is formed. Since there is no concentrated application, it is possible to more effectively prevent the piezoelectric element 91 and the reinforcing plate 73 from being separated.

(13) In the piezoelectric vibrating body 90, in order to improve the driving efficiency, the reinforcing plate 73 vibrates the protrusion 332 that is in contact with the rotor 40 as the driven body to the greatest extent. The peeling force to peel off the plate 73 is maximized in the vicinity of the protrusion 332 of the reinforcing plate 73, but the chamfered portion 911 of the piezoelectric element 91 is located at the position where the protrusion 332 of the reinforcing plate 73 protrudes. Since the position of the projection 332 where the peeling force is maximum and the position of the chamfered portion 911 for preventing the piezoelectric element 91 and the reinforcing plate 73 from peeling off are almost the same, Separation can be effectively prevented.
Further, the protrusion 333 formed at the diagonal position with respect to the protrusion 332 in the reinforcing plate 73 also vibrates greatly in the same manner as the protrusion 332, so that the chamfered portion 912 can prevent peeling more effectively. .

(14) As shown in FIG. 8, a part of the outer periphery 91 </ b> B of the piezoelectric element 91 overlaps the protrusion 332 of the reinforcing plate 73 along the thickness direction (the direction perpendicular to the paper surface in FIG. 8). The projection 332 is suppressed from vibrating in the thickness direction, and the projection 332 can be vibrated in a vibration plane substantially perpendicular to the thickness direction (a plane parallel to the paper surface in FIG. 8). Efficiency can be realized. Similarly, since a part of the outer periphery 91D of the piezoelectric element 91 overlaps the protrusion 333 of the reinforcing plate 73 along the thickness direction, the protrusion 333 is suppressed from vibrating in the thickness direction, and the thickness direction is increased. The projection 333 can be caused to vibrate in the same manner as the projection 332 in a substantially vertical vibration plane. Therefore, the protrusion 332 and the protrusion 333 can be well balanced, and the expected driving efficiency can be realized by keeping the protrusion 332 in a desired vibration state.

(15) Since the width B of the chamfered portions 911 and 912 of the piezoelectric element 91 is larger than 1/50 of the width b of the protrusion 332 of the reinforcing plate 73 (0.02 × b <B), the chamfered portions 911 and 912 The effect of preventing peeling due to the formation of can be sufficiently exhibited.

(16) The chamfered portions 911 and 912 themselves are enlarged by increasing the length L along the length direction (left and right direction in FIG. 8) of the chamfered portions 911 and 912 (length L> width B). Therefore, the peeling force can be dispersed according to the size of the chamfered portions 911 and 912, and the peeling between the piezoelectric element 91 and the reinforcing plate 73 can be made difficult to occur.

[Fourth Embodiment]
Subsequently, a fourth embodiment of the present invention will be described with reference to FIG. The piezoelectric actuator according to this embodiment is different from the piezoelectric actuator according to each of the embodiments described above in that the rotor can be rotationally driven in the forward direction and the reverse direction. Therefore, the arrangement of the chamfered portion formed in the piezoelectric element is the third embodiment. Is different.

  FIG. 10 is a plan view of the piezoelectric vibrating body 100 constituting the piezoelectric actuator of this embodiment. The piezoelectric vibrating body 100 is configured by stacking piezoelectric elements 101 on both front and back surfaces of a reinforcing plate 103. Then, on the surface of the piezoelectric element 101, an electrode formed by plating, sputtering, vapor deposition, or the like of gold or nickel is divided by an etching groove or the like, so that five drives are symmetrical with respect to the center line C along the longitudinal direction. Electrodes 111-115 are provided.

Further, the protrusion 1032 and the protrusion 1033 of the reinforcing plate 103 are formed so as to protrude from the intermediate position in the width direction (vertical direction in FIG. 10) of the reinforcing plate 103 along the length direction (horizontal direction in FIG. 10). Has been. Specifically, the protrusion 1032 is formed to project from an intermediate position of the outer periphery 91B along a direction perpendicular to the outer periphery 91B, and the protrusion 1033 is formed from an intermediate position of the outer periphery 91D to the outer periphery 91D. Projecting along a vertical direction. With respect to the drive electrodes 111 to 115 described above, by switching the target to which the drive voltage is applied with respect to the center line C, the vibration behavior of the piezoelectric vibrating body 100 changes axisymmetrically and the directions of the elliptical trajectories of the protrusions 1032 and 1033 are changed. Instead, the rotor 40 (FIG. 2) can be rotated forward or backward. Specifically, when a voltage is applied to the drive electrodes 111, 113, and 115, the rotor 40 rotates in the forward direction, and when a voltage is applied to the drive electrodes 112, 114, and 115, the rotor 40 rotates in the reverse direction.
In addition, since the vibration behavior of the piezoelectric vibrating body 100 according to the present embodiment is switched symmetrically with respect to the center line C, a pair of arm portions 334 that support the piezoelectric vibrating body 100 are provided on both sides in the width direction of the piezoelectric vibrating body 100. , Each is fixed to the main plate.

  In addition, the outer periphery 91B and the outer periphery 91D of the piezoelectric element 101 overlap along the thickness direction (the direction perpendicular to the paper surface in FIG. 10) on the entire base portions of the protrusion 1032 and the protrusion 1033 of the reinforcing plate 103, respectively. Therefore, the protrusion 1032 and the protrusion 1033 are suppressed from vibrating in the thickness direction, and thus the protrusion 1032 and the protrusion 1033 are vibrated in a vibration plane substantially perpendicular to the thickness direction (a plane parallel to the paper surface in FIG. 10). And a desired driving efficiency can be realized.

The piezoelectric element 101 has a substantially rectangular shape in plan view, and four chamfered portions 911, 912, and 913 each having a chamfered shape at each of the four corner portions of the substantially rectangular shape in plan view. , 914 are formed. Here, the four chamfered portions 911 to 914 have the same shape as the chamfered portions 911 and 912 (FIG. 8) in the third embodiment.
Note that the lower left and upper left corners (in FIG. 10) of the piezoelectric element 101 are the corners closest to the protrusion 1032 of the reinforcing plate 103, and chamfered portions 911 and 913 are formed at both corners, respectively. Similarly, the upper right and lower right corners (in FIG. 10) of the piezoelectric element 101 are the corners closest to the reinforcing plate 103, and chamfered portions 912 and 914 are formed at both corners, respectively.

According to this embodiment, in addition to the effect in 3rd Embodiment, there exist the following effects.
(17) In the piezoelectric element 101, a protrusion 1032 and a protrusion 1033 of the reinforcing plate 103 are formed to project from each other at an intermediate position between two corners adjacent to each other. Here, since the protrusion 1032 and the protrusion 1033 vibrate substantially in the same manner, substantially equal peeling forces are applied to the four corners of the piezoelectric element 101. Since these four corners are respectively formed with chamfered portions 911 to 914 having the same shape for reducing the peeling force, the peeling force can be effectively reduced. Separation of the reinforcing plate 103 can be effectively prevented.

(18) Further, in the substantially rectangular shape in plan view of the piezoelectric element 101, the contour lines of the four outer peripheries 91A to 91D and the four chamfered portions 911 to 914 are smoothly connected to form an outer periphery without a pointed portion. In addition, since the peeling force for separating the piezoelectric element 101 and the reinforcing plate 103 is not concentrated on one point, it is possible to effectively prevent the piezoelectric element 101 and the reinforcing plate 103 from being separated. can do.

(19) Since the chamfered portions 911 to 914 are formed at the four corners of the piezoelectric element 101 and the reinforcing plate 103 is exposed at the four corners, the heat dissipation effect is higher than that of the third embodiment. For this reason, the size of the reinforcing plate 103 is substantially the same as that of the piezoelectric element 101 even if the reinforcing plate 73 is not formed so as to protrude from the four sides of the piezoelectric element as in the second and third embodiments. A sufficient heat dissipation effect can be obtained. Thereby, the piezoelectric vibrating body 100 can be reduced in size and space can be saved.

[Modification of the present invention]
Although the best configuration for carrying out the present invention has been specifically described above, the present invention is not limited to this. That is, the invention has been illustrated and described primarily with respect to particular embodiments, but may be configured for the above-described embodiments without departing from the scope and spirit of the invention. Various modifications and improvements can be made by those skilled in the art in terms of materials, quantity, and other detailed configurations.
The description limiting the shape, material, etc. disclosed above is an example for easy understanding of the present invention, and does not limit the present invention. The description by the name of the member which removes a part or all of the limitation is included in the present invention.

For example, in each of the above embodiments, a three-layer structure in which the piezoelectric elements 31 and 32 are bonded to the front and back surfaces of the reinforcing plate 33 and the like is shown. Large power can be achieved by laminating about 2 to 10 or more elements 31 and 32 to form a multilayer structure.
An example of such a piezoelectric vibrator is shown in FIGS. FIG. 11 is an exploded perspective view of the piezoelectric vibrating body 200, and FIG. 12 is a side view of the piezoelectric vibrating body 200.
The piezoelectric vibrating body 200 is configured by stacking a total of six piezoelectric elements 201A to 201C and 201D to 201F on each of the front and back surfaces of the reinforcing plate 203, and the protrusions 332 ′ and 333 on the reinforcing plate 203. 'Is formed, and the rotor 40 is rotationally driven by pressing of the protrusion 332'. Here, although the more specific shape of the reinforcing plate 203 and the configuration of the electrodes provided in each of the piezoelectric elements 201A to 201F are slightly different from those of the above embodiments, the piezoelectric vibrating body 200 also includes the reinforcing plate 203. A recess 3311 is formed on the outer periphery of the side surface. For this reason, when the piezoelectric elements 201A to 201F and the reinforcing plate 203 are sequentially stacked and bonded to each other, an adhesive is accumulated in the recess 3311, and the piezoelectric elements 201A to 201F or the piezoelectric elements 201C and 201D and the reinforcing plate 203 It is possible to prevent the adhesive from flowing out from between. Thereby, it is possible to ensure reliability without causing adhesion failure. In addition, the piezoelectric vibrating body 200 also has substantially the same effects as those described in the above embodiments.
Further, in each of the piezoelectric elements 201A to 201F, chamfered portions 2011A to 2011F and 2012A to 2012F are provided in the vicinity of the base portion of the protrusion 333 ′ and in the vicinity of the base portion of the protrusion 332 ′, respectively. As a result, even when a large power is applied by the laminated piezoelectric elements, stress concentration is mitigated in the same manner as in the other embodiments described above, thereby preventing separation between the reinforcing plate 203 and the piezoelectric elements 201C and 201D. it can. In addition, since heat dissipation is difficult compared to the bonding surface with metal, the bonding surface between the piezoelectric elements 201A and 201B, 201E and 201F, and the like, where the temperature of the bonding surface easily rises and the usage conditions are severe, is also peeled off. Can be prevented.

Further, in each of the above embodiments, the recess 3311 such as the reinforcing plate 33 is formed in a circular arc shape in cross section, but is not limited thereto, and may be formed in a U shape in cross section or a V shape. In addition to the continuously extending groove-shaped recess 3311 shown in each of the above embodiments, for example, a plurality of recesses may be formed in a scattered manner on the outer periphery of the side surface of the reinforcing member.
In the first to third embodiments, the reinforcing plates 33, 73, and 93 have the protrusions 332 and 333 and the arm portion 334. However, the present invention is not limited to this. For example, the arm portions are provided on both side surfaces of the reinforcing plate. These may be provided, and the vibrating body may be fixed on both sides by these arm portions.
Further, these protrusions and arms may not be formed on the reinforcing member. For example, the vibration of the piezoelectric vibrating body is transmitted to the driven body by the contact of the corners of the rectangular reinforcing member, The vibrating body may be attached and fixed to the attached portion such as the ground plate by means such as screwing with a hole formed in the shape reinforcing member.

In each of the above embodiments, a wristwatch is illustrated as an application example of a piezoelectric actuator. However, the present invention is not limited to this, and the present invention can also be applied to a pocket watch, a table clock, a wall clock, and the like. In these various timepieces, for example, it can be used as a mechanism for driving a mechanism doll or the like.
In addition to the watch, the piezoelectric actuator of the present invention can be used as appropriate for a camera zoom and autofocus mechanism, a film winding mechanism, a paper feed mechanism for a printer, a mechanism for driving toys such as vehicles and dolls, and the like. . The piezoelectric actuator of the present invention can be widely used in various electronic devices such as a portable information terminal and a telephone, including a camera, a printer, and a toy.
The driven body in the piezoelectric actuator is not limited to the rotor that is rotationally driven, but may be a slider that is linearly driven.

1 is an external view of a timepiece according to a first embodiment of the present invention. The top view of the piezoelectric actuator in the said embodiment. The perspective view of the piezoelectric vibrating body in the said embodiment. The top view which shows the assembly process of the piezoelectric vibrating body in the said embodiment. FIG. 4 is a side cross-sectional view showing an assembly process of the piezoelectric vibrating body in the embodiment. The top view of the piezoelectric actuator in 2nd Embodiment of this invention. FIG. 4 is a side cross-sectional view showing an assembly process of the piezoelectric vibrating body in the embodiment. The top view of the piezoelectric vibrating body in 3rd Embodiment of this invention. The graph which shows the drive performance of the piezoelectric vibrating body in the said embodiment. The top view of the piezoelectric vibrating body in 4th Embodiment of this invention. The disassembled perspective view of the piezoelectric actuator in the modification of this invention. The side view of the piezoelectric actuator in the modification of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Electronic timepiece (clock), 1 ... Movement (time measuring means), 2 ... Dial (time information display part), 3 ... Hour hand (time information display part), 4 ... Minute hand (Time information display part), 5 ... second hand (time information display part), 6 ... second chronograph hand (time information display part), 7 ... minute chronograph hand (time information display part), 20 ... Piezoelectric actuators, 30, 70, 90, 100, 200 ... Piezoelectric vibrators, 31, 32, 91, 101, 201A to 201F ... Piezoelectric elements, 33, 73, 103, 203 ... Reinforcement Plate (reinforcing member), 40 ... rotor (driven body), 61A, 61B, 61C, 81 ... pin, 311 ... laminated surface, 321 ... laminated surface, 331A, 331B ... laminated Surface, 731A, 731B ... laminated surface, 811 ... small diameter part ( According to the difference), 812 ... according to the large diameter portion (stepped), 911-914.. Chamfer, 3311 ... recess, AD ... adhesive.

Claims (10)

A piezoelectric vibrator having a piezoelectric element provided with an electrode and a reinforcing member laminated with the piezoelectric element, and vibrating by applying a voltage to the electrode,
The laminated surfaces of the piezoelectric element and the reinforcing member which are laminated and laminated are bonded to each other with an adhesive,
A concave portion that is recessed in a direction intersecting with the lamination direction of the reinforcing member and the piezoelectric element is formed on the outer peripheral surface of the reinforcing member. The piezoelectric vibrating body according to claim 1,
The area of the laminated surface of the reinforcing member is larger than the area of the laminated surface of the piezoelectric element,
When the reinforcing member is laminated with the piezoelectric element, the reinforcing member protrudes from the outer periphery of the piezoelectric element. In the piezoelectric vibrating body according to claim 1 or 2,
The piezoelectric element and the reinforcing member are formed in a plate shape, and the surfaces along the plane direction are overlapped,
The concave portion extends in a continuous groove shape along the side surface of the reinforcing member. In the piezoelectric vibrating body according to any one of claims 1 to 3,
At least one corner portion of the piezoelectric element is formed with a chamfered portion that forms the corner portion into a chamfered shape. The piezoelectric vibrating body according to claim 4,
The chamfered portion of the piezoelectric element has a contour line formed in a curved shape,
A piezoelectric vibrator characterized by that. A method of manufacturing a piezoelectric vibrating body having a piezoelectric element provided with an electrode and a reinforcing member laminated with the piezoelectric element and vibrating by applying a voltage to the electrode,
While abutting and positioning the piezoelectric element and the reinforcing member on a pin extending in the stacking direction of the piezoelectric element and the reinforcing member,
These piezoelectric elements and reinforcing members are bonded to each other with an adhesive,
The piezoelectric element and the reinforcing member are pressurized along the laminating direction. A method for manufacturing a piezoelectric vibrator. In the manufacturing method of the piezoelectric vibrating body according to claim 6,
A step is provided in the axial direction of the pin,
The area of the laminated surface laminated with the piezoelectric element of the reinforcing member is set larger than the area of the laminated surface laminated with the reinforcing member of the piezoelectric element,
The reinforcing member is laminated with the piezoelectric element such that the laminated surface of the reinforcing member extends outside the laminated surface of the piezoelectric element, and is brought into contact with the stepped side of the step of the pin. A method for manufacturing a piezoelectric vibrating body. The piezoelectric vibrator according to any one of claims 1 to 5, or the piezoelectric vibrator manufactured by the method according to any one of claims 6 and 7, and driven by the vibration of the piezoelectric vibrator. And a driven body. An electronic apparatus comprising the piezoelectric actuator according to claim 8. The electronic device according to claim 9, wherein the electronic device is a timepiece including a time measuring unit and a time information display unit that displays information timed by the time measuring unit.

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