JP2008218953A - Piezoelectric vibrating body, electronic device, and manufacturing method of piezoelectric vibrating body - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a piezoelectric vibration body capable of preventing the deterioration of characteristics of piezoelectric strips caused by self-heating, capable of significantly improving the long-term reliability of junction between the piezoelectric strips and its reinforcing plate, and capable of stabilizing the electrical connection of the reinforcing plate and surfaces of the piezoelectric strips. <P>SOLUTION: By forming electrodes 210, 220 with proper solder wettability between the reinforcing plate 22 and the respective piezoelectric strips 21, 21, the piezoelectric strips 21, 21, and the reinforcing plate 22 are jointed by solder 31. As a result of this, the problem of the self-heating of the piezoelectric strips 21, 21 is solved since heat from the piezoelectric strips 21, 21 is dissipated to the reinforcing plate 22 and further to a device case via the solder 31, the long-term reliability of the junction is secured since high connection strength can be obtained due to this the junction. Furthermore, the continuity of the reinforcing plate 22 to the surfaces of the piezoelectric strips 21, 21 is stabilized since the solder 31 spreads properly between jointing surfaces of the piezoelectric elements 21, 21 and jointing surfaces of the reinforcing plate 22. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

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

  Conventionally, as a piezoelectric actuator, a piezoelectric vibrating body has been developed in which plate-like piezoelectric elements are laminated on the front and back surfaces of a reinforcing plate made of stainless steel or the like (for example, Patent Document 1). In such a piezoelectric actuator, when an AC voltage is applied in the thickness direction of each piezoelectric element polarized symmetrically in the thickness direction, each piezoelectric element expands and contracts in the in-plane direction, and the entire piezoelectric vibrator including the reinforcing plate is formed. Excited. By transmitting the vibration of the piezoelectric vibrating body, a driven body such as a rotor is driven.

Here, the piezoelectric element and the reinforcing plate are joined with a non-conductive adhesive such as an epoxy resin, and FIG. 33 shows a joining cross section of the piezoelectric element 91 and the reinforcing plate 92 with the adhesive AD interposed therebetween. It was.
In FIG. 33, an electrode 911 is formed on the bonding surface of the piezoelectric element 91 with the reinforcing plate 92, and an electrode 921 is also formed on the bonding surface of the reinforcing plate 92 with the piezoelectric element 91. These electrodes 911 and 921 are provided with irregularities according to their surface roughness, and these irregularities are in random contact. That is, the piezoelectric element 91 and the reinforcing plate 92 are electrically connected by microscopic contact between the electrodes 911 and 921.
In this way, when the piezoelectric element 91 and the reinforcing plate 92 are bonded together, it is necessary to perform bonding after the thickness of the adhesive AD is made uniform in order to ensure contact between the electrodes 911 and 921. For this reason, in Patent Document 1, an adhesive layer is formed in advance by discharging an adhesive onto a sheet placed smoothly on a silicon wafer. Then, after the adhesive layer formed on the sheet is transferred to the piezoelectric element, the piezoelectric element and the reinforcing plate are positioned and laminated with a jig pin, and the adhesive layer is cured by pressing and heating. As described above, the process of bonding the piezoelectric element and the reinforcing plate is complicated and complicated. In particular, the adhesive layer forming process includes many processes for making the thickness of the adhesive layer thin and uniform.

  On the other hand, it is conceivable to improve the conduction stability by using a conductive adhesive for bonding the piezoelectric element and the reinforcing plate, but the conductive adhesive generally has a weak adhesive force. For this reason, a method of using a conductive adhesive and a non-conductive adhesive in combination has been proposed (Patent Document 2).

International Publication No. WO2004 / 043617 (FIG. 2, page 6, line 6 to page 7, line 28) Japanese Patent No. 2919658 (FIGS. 3 and 4)

However, the piezoelectric actuator in which the piezoelectric element and the reinforcing plate are bonded as described above has the following problems.
(Problem 1) Degradation of characteristics due to self-heating of the piezoelectric element Since the adhesive between the piezoelectric element and the reinforcing plate acts as a heat insulating material, the heat generated by the expansion and contraction of the piezoelectric element is not dissipated and the temperature of the piezoelectric element increases. To go. When the surface temperature of the piezoelectric element is measured, it is found that the temperature is about 150 ° C., which may affect the characteristics of the piezoelectric element. In addition, when the temperature of the piezoelectric element exceeds the glass transition temperature of the adhesive, there is a concern that the adhesive is softened and the piezoelectric element and the reinforcing plate are peeled off.
In order to cope with such a problem of self-heating of the piezoelectric element, it is necessary to cool the piezoelectric element by adding a heat radiation fin, a copper casing, a fan, or the like to the piezoelectric actuator, and the apparatus has been enlarged. In other words, the advantage of the piezoelectric actuator, which is high power and can be reduced in size, has been suppressed.

(Problem 2) The long-term reliability of bonding is low. Mechanical coupling (anchor effect); Physical interaction (intermolecular force), C.I. Although composed of three chemical interactions, these A to C were not sufficient in terms of long-term bonding reliability.

(Problem 3) Unstable conduction As shown in FIG. 33, since the piezoelectric element 91 and the reinforcing plate 92 joined by the adhesive AD are electrically connected by microscopic contact between the surface irregularities of each surface, In order to stabilize the conduction between the piezoelectric element and the reinforcing plate, a complicated process for managing the thickness of the adhesive layer as in Patent Document 1 is required. That is, the production efficiency was poor.
Further, foreign matters such as dust are easily mixed in the adhesive layer in the course of such a complicated process, and there is a problem that the conduction resistance between the piezoelectric element and the reinforcing plate is increased by the foreign matters.
On the other hand, in the method of using a conductive adhesive and a non-conductive adhesive in combination as in Patent Document 2, an apparatus and a process for applying the adhesive are individually performed for each of the conductive adhesive and the non-conductive adhesive. Since it is necessary, there is a drawback in manufacturing efficiency.

  An object of the present invention is to provide a piezoelectric vibrator, an electronic device, and a method for manufacturing a piezoelectric vibrator that can solve any of the above (Problem 1) to (Problem 3), and has excellent heat resistance and durability. To bring electronic equipment.

  The piezoelectric vibrating body of the present invention includes a piezoelectric element and a reinforcing member joined to the piezoelectric element, and a joint portion of the piezoelectric element with the reinforcing member includes a metal film, and the reinforcing member The joint portion of the member with the piezoelectric element is configured to have a metal coating, or the oxide film of the joint portion is removed, and the piezoelectric element and the reinforcing member are connected to each of the joints. In the part, it is characterized by being joined by a metal joining material.

Here, a metal film having good wettability with the metal bonding material is formed on the piezoelectric element, and a metal film with good wettability with the metal bonding material is formed on the reinforcing member, or the oxide film is removed. Thus, the piezoelectric element and the reinforcing member are reliably joined.
Metal brazing materials include gold brazing (Au / Ag / Cu / Zn / In), silver brazing (Ag / Cu / Zn / Sn5), copper brazing, phosphor copper brazing (Cu / P / Sn), nickel brazing. Examples thereof include (Ni / Si / P) and palladium brazing (Pd / Ag / Cu). Examples of the metal having good wettability with such a metal bonding material include Au, alloys of Pd and Ag, and the like, and a metal film made of such a metal is obtained by electroplating, dry plating, electroless plating, or the like. What is necessary is just to form.
Moreover, as a metal of the metal film formed on the piezoelectric element or the reinforcing member, Ni or Cu metal film can be considered in addition to the above Au or the like. Since these are highly oxidizable metals, they must be handled in an inert atmosphere, for example, an N ₂ atmosphere.
The reinforcing member is made of a metal material such as stainless steel or phosphor bronze. As a method for removing the oxide film on the surface of the reinforcing member, there is plasma etching or the like. In addition, when the base material of the reinforcing member itself is formed of a metal material having good wettability such as Au, the oxide film of the reinforcing member is removed unless the surface layer of the reinforcing member is oxidized. .
In addition, a plastic molding material such as polyimide (280 ° C.), PPS (250 ° C.), PET (230 ° C.), etc. (continuous use temperature in parentheses) can be selected as the material of the reinforcing member. In the case of a plate, joining with a metal joining material becomes possible by forming a metal film. Since such a material can be molded, it can be processed in a short time even if the shape of the reinforcing member is complicated.

Here, the electrode formed on the piezoelectric element, the electrode formed on the reinforcing member, and the solder layer between the piezoelectric element and the reinforcing member when the piezoelectric element and the reinforcing member are joined with solder as a metal joining material. Each thickness is illustrated. The film thickness of the electrode formed in the piezoelectric element can be set to 0.1 to 3.0 [mu] m for the base and 0.05 to 3.0 [mu] m for the surface, respectively, by illustrating the film thickness of the base layer and the surface layer, respectively. In addition, the range of a preferable film thickness is 0.5-2.0 micrometers of base | substrates, and 0.02-1.0 micrometer of surface layers.
Moreover, also about the film thickness of the electrode formed in a reinforcement member, when the film thickness of a base layer and a surface layer is illustrated, respectively, it can set to base 0.1-3.0 micrometers and surface layer 0.05-3.0 micrometers, respectively. In addition, the range of a preferable film thickness is 0.5-2.0 micrometers of base | substrates, and 0.02-1.0 micrometer of surface layers.
And the thickness of a solder layer can be set to 1.0-50.0 micrometers, and preferable thickness is 5.0-20.0 micrometers.

According to the present invention, heat of the piezoelectric element is radiated to the reinforcing member via the metal bonding material between the piezoelectric element and the reinforcing member, and further radiated to the equipment housing or the like to which the reinforcing member is fixed. That is, since the piezoelectric element is not thermally insulated by the adhesive as in the prior art, the temperature rise of the piezoelectric element is suppressed. As a result, the characteristics of the piezoelectric element are stabilized, reliability can be ensured, and it is not necessary to add a radiating fin or the like, so that the piezoelectric vibrator can be downsized. Can be pulled out.
Here, since the thermal conductivity of the metal bonding material is remarkably higher than that of the conventionally used resin-based adhesive, the heat dissipation of the piezoelectric element is efficiently performed through the metal bonding material. Specifically, the thermal conductivity of the epoxy resin adhesive is about 1.0 W / m · k, whereas the thermal conductivity of Sn as the main component of the solder is about 68 W / m · k, Remarkably high.

  Further, in the joining by the metal joining material, an alloy layer is formed between the metal joining material and the counterpart material. That is, since the piezoelectric element surface and the metal bonding material, and the metal bonding material and the reinforcing plate surface are bonded to each other, a higher bonding force than in the case of bonding based on intermolecular force can be obtained. Thereby, the long-term reliability of bonding can be ensured.

Still further, according to the bonding by the metal bonding material, the metal bonding material enters the gaps between the concave and convex portions of the bonding surface of the piezoelectric element and the bonding surface of the reinforcing member, and the piezoelectric element and the reinforcing member are connected to the entire bonding surface. Conducted at. That is, since the metal bonding material comes into full contact with each of the piezoelectric element and the reinforcing member, and the piezoelectric element and the reinforcing member are conducted through the metal bonding material, the conduction between the piezoelectric element and the reinforcing member is extremely stable. In addition, an electrically stable conduction resistance can be obtained. Here, the reinforcing member is also used as an electrode of the piezoelectric element, and performs both mechanical holding of the piezoelectric element and electrical conduction of the piezoelectric element.
In the present invention in which bonding is performed, a complicated manufacturing process for forming a thin adhesive layer with a uniform thickness is no longer necessary, so that manufacturing efficiency can be improved.
As described above, according to the present invention, any of (Problem 1) to (Problem 3) can be solved.

By the way, it is preferable that the formation region of the metal film formed on the piezoelectric element is formed in a region slightly inside from the outer end of the piezoelectric element constituting the outer shape of the piezoelectric element. In particular, the metal of the piezoelectric element is located in a region located on the inner side from the position of the outer end of the piezoelectric element by a dimension of 1/3 or more, preferably 1/2 or more, more preferably 1/1 or more of the thickness of the piezoelectric element. It is preferable that a film is formed.
Similarly, in the reinforcing member, the region where the metal film is formed on the reinforcing member or the region where the oxide film is removed is from the outer end position constituting the outer shape of the reinforcing member. It is preferably formed in a region slightly closer to the inside. In particular, the metal film of the reinforcing member is formed on the inner side from the outer end position of the reinforcing member by a dimension of 1/3 or more, preferably 1/2 or more, more preferably 1/1 or more of the thickness of the reinforcing member. It is preferable that the formed region or the region be a region where the oxide film is removed.

As described above, the metal film formation region in the piezoelectric element and the metal film formation region / oxide film removal region in the reinforcing member are configured to be slightly inward from the outer end position as described above. By joining the piezoelectric element and the reinforcing member, the metal bonding material may protrude from the outer shape of the piezoelectric element or outward from the outer shape of the reinforcing member, particularly on the side surface of the piezoelectric element or the side surface of the reinforcing member. It becomes possible to prevent reliably. Thereby, it is possible to prevent the deterioration of the vibration characteristics of the piezoelectric vibrating body due to the bonding between the piezoelectric element and the reinforcing member even more reliably.
Here, the configuration in which the region is slightly inward from the outer end position as described above may be applied to one of the piezoelectric element and the reinforcing member, or may be applied to both of them.
In addition, when the planar dimensions of the piezoelectric element and the reinforcing member are different, and the sizes of their joint surfaces are different, the formation region of the metal film and the region from which the oxide film is removed are determined. It is preferable that the piezoelectric element and the reinforcing member be held inside the outer edge portion having the smaller joint surface.

  In addition, the piezoelectric vibrating body of this invention should just be provided with one or more each of the piezoelectric element and reinforcement member which are mutually joined, and the number of each of a piezoelectric element and a reinforcement member is not ask | required. That is, a configuration in which one reinforcing member is interposed between two piezoelectric elements and a configuration in which one piezoelectric element is interposed between two reinforcing members are also included in the piezoelectric vibrator of the present invention. included.

In the piezoelectric vibrating body of the present invention, it is preferable that the metal bonding material is a solder.
According to the present invention, the Curie point of a general piezoelectric element such as PZT (registered trademark) is about 300 to 400 ° C., whereas the melting point of solder is about half that of the low melting point. The deterioration of the characteristics of the piezoelectric element can be prevented more reliably. Thereby, reliability can be improved more.

In the piezoelectric vibrating body of the present invention, the reinforcing member is formed in a plate shape, and a metal film that forms at least a part of the joining portion is formed on a flat surface of the reinforcing member, and on the side surface of the reinforcing member The metal coating is not formed, and the wettability with the metal bonding material in the metal coating on the plane of the reinforcing member is preferably better than the wettability with the metal bonding material on the side surface.
Here, in order to obtain a configuration in which the metal film is formed only on the flat surface of the reinforcing member and the metal film is not formed on the side surface of the reinforcing member, for example, a pre-plated material such as Au is used, and individual punching is performed. The reinforcing member may be formed.

According to this invention, it is possible to keep the metal bonding material only at the bonding portion where the metal film is formed on the reinforcing member, and prevent the metal bonding material from flowing out to the side surface of the reinforcing member that is not bonded to the piezoelectric element.
Here, since the metal bonding material does not flow out to the side surface of the reinforcing member, the metal bonding material is transmitted through a positioning jig or the like standing on the side surface of the reinforcing member when the piezoelectric element and the reinforcing member are bonded. It can prevent flowing to the outer periphery of the element. That is, if the metal bonding material adheres to a part of the outer peripheral portion of the reinforcing member, the piezoelectric vibrating body loses weight balance and shifts the vibration characteristics. However, variations in vibration characteristics due to such factors can be prevented.

When this piezoelectric vibrating body is used as a piezoelectric actuator, the side surface of the reinforcing member can be brought into contact with a driven body such as a rotor, and the driven body can be driven by frictional resistance during vibration at the contact portion. However, since the metal bonding material does not flow out to the side surface of the reinforcing member, the side surface of the reinforcing member can be in a state where the substrate of the reinforcing member is exposed. Thereby, the uniform frictional resistance between the piezoelectric vibrating body and the driven body can be maintained.
Further, since the metal bonding material does not wrap around from the side surface of the reinforcing member to the electrode formed on the surface opposite to the reinforcing member of the piezoelectric element, the reinforcing member used also as the electrode of the piezoelectric element, and this reinforcement It is possible to prevent a short circuit between the electrode of the piezoelectric element to which a potential different from the potential applied to the member is applied.

  In the piezoelectric vibrating body of the present invention, the reinforcing member includes a reinforcing member main body having a joint portion with the piezoelectric element, and a portion other than the reinforcing member main body, and at least the portion in the portion other than the reinforcing member main body. A bonding material non-adhesive portion in which the wettability with the metal bonding material is inferior to the wettability with the metal bonding material at the bonding portion of the reinforcement member main body is formed at a position in the vicinity of the bonding portion of the reinforcing member main body. It is preferable.

  According to this invention, the formation of the bonding material non-adhering portion gives a difference in wettability between the joint portion in the reinforcing member main body and the portion other than the reinforcing member main body in the reinforcing member. It is possible to prevent the metal bonding material from flowing out to other portions. As a result, it is possible to prevent the vibration characteristics from shifting and the vibration characteristics from varying, and a short circuit between the electrodes.

In the piezoelectric vibrating body of the present invention, it is preferable that the portion other than the reinforcing member main body is a support portion that is connected to the reinforcing member main body and supports the piezoelectric element.
Here, the bonding material non-adhering portion may be formed on the entire support portion.

  According to this invention, since the bonding material non-adhering portion is formed in the support portion, it is possible to restrict the metal bonding material from protruding from the reinforcing member body to the support portion. Thereby, it is possible to prevent the vibration characteristics from shifting and the vibration characteristics from varying.

In the piezoelectric vibrating body of the present invention, a piezoelectric actuator that drives the driven body by transmitting vibrations of the piezoelectric vibrating body is provided, and portions other than the reinforcing member main body are connected to the reinforcing member main body and are driven. It is preferable that the contact portion is in contact with the body.
Here, the bonding material non-adhering portion may be formed on the entire contact portion.

According to this invention, since the bonding material non-adhering portion is formed in the contact portion, the metal bonding material can be prevented from protruding from the reinforcing member main body to the contact portion. Thereby, it is possible to prevent the vibration characteristics from shifting and the vibration characteristics from varying.
Moreover, since the base of the reinforcing member can be exposed at the contact portion, a uniform frictional resistance with the driven body can be maintained.

  In the piezoelectric vibrating body of the present invention, only the reinforcing member main body of the reinforcing member is formed with a metal coating that constitutes the joining portion, and the joining material non-adhering portion is a non-coating in which no metal coating is formed on the reinforcing member. It is preferable to be a part.

  According to the present invention, a non-coating portion where the base of the reinforcing member is exposed is formed by forming no metal coating on a part of the reinforcing member, and the non-coating portion whose wettability is inferior to that of the metal coating is not a bonding material. Functions as an adhesion part. That is, it is possible to form the bonding material non-adhering portion using the non-coating portion without providing other members or the like that function as the bonding material non-adhering portion.

  In the piezoelectric vibrator of the present invention, at least a part of the metal film that constitutes the joint portion is continuously formed on the reinforcing member main body and a portion other than the reinforcing member main body, and the bonding material non-adhering portion is It is preferably provided on the surface of the metal coating.

  According to this invention, since the bonding material non-adhering portion is provided on the surface of the metal film, unlike the configuration in which the non-coating portion is the bonding material non-adhering portion, masking is not required when forming the metal film. Can be. That is, a metal film can be simply formed on the reinforcing member.

In the piezoelectric vibrating body of the present invention, it is preferable that the bonding material non-adhering portion is formed of an insulating member.

  According to the present invention, it is possible to form the bonding material non-adhering portion using, for example, an epoxy insulating resin. Such a resin-based insulating member can be directly provided on the reinforcing member by, for example, printing using an insulating ink.

  In the piezoelectric vibrating body of the present invention, the reinforcing member includes a reinforcing member main body having a joint portion with the piezoelectric element, and a portion other than the reinforcing member main body, and the reinforcing member main body includes the joint portion. It is preferable that a position in the vicinity of a portion other than the reinforcing member main body in at least one of the piezoelectric element and the reinforcing member main body is a non-coating portion where no metal film is formed.

  According to this invention, by forming the non-coating portion, each of the position near the piezoelectric element and the reinforcing member main body other than the reinforcing member main body (for example, the support portion and the contact portion) and the joint portion of the reinforcing member main body Since the difference in wettability is given, the outflow of the metal bonding material from the reinforcing member main body to a portion other than the reinforcing member main body can be more reliably regulated. As a result, it is possible to prevent the vibration characteristics from shifting and the vibration characteristics from varying, and a short circuit between the electrodes.

  In the piezoelectric vibrating body of the present invention, it is preferable that the portion other than the reinforcing member main body is a support portion that is connected to the reinforcing member main body and supports the piezoelectric element.

  According to the present invention, in the piezoelectric element or the reinforcing member main body, the wettability at each of the joint portion and the vicinity of the support portion is different, so that the metal bonding material protrudes from the joint portion to the support portion. Can be regulated. Thereby, it is possible to prevent the vibration characteristics from shifting and the vibration characteristics from varying.

  In the piezoelectric vibrating body of the present invention, a piezoelectric actuator that drives the driven body by transmitting vibrations of the piezoelectric vibrating body is provided, and portions other than the reinforcing member main body are connected to the reinforcing member main body and are driven. It is preferable that the contact portion is in contact with the body.

According to the present invention, in the piezoelectric element or the reinforcing member main body, since the wettability at each of the joining portion and the position near the abutting portion is different, the metal joining from the joining portion toward the abutting portion is performed. It is possible to regulate the protruding material. Thereby, it is possible to prevent the vibration characteristics from shifting and the vibration characteristics from varying.
Moreover, since the base of the reinforcing member can be exposed at the contact portion, a uniform frictional resistance with the driven body can be maintained.

  In the piezoelectric vibrating body of the present invention, the piezoelectric element and the reinforcing member are stacked and bonded to each other. At the time of bonding, the piezoelectric element and the reinforcing member extend along the stacking direction and contact the outer peripheral portion of the piezoelectric element and the outer peripheral portion of the reinforcing member. A jig for contact is used, and the reinforcing member is formed with a metal film that constitutes the joint portion, and a metal film is not formed in the vicinity of the jig in at least one of the piezoelectric element and the reinforcing member. The non-coating portion is preferred.

  According to this invention, in the piezoelectric element or the reinforcing member main body, since the wettability is different between the joint portion and the position near the jig, the metal bonding material protrudes from the joint portion to the jig. Can be regulated. Thereby, it is possible to prevent the metal bonding material from flowing along the jig to the outer peripheral portion of the reinforcing member or the piezoelectric element and shifting the vibration characteristics. In addition, a short circuit between the electrodes can be prevented.

  In the piezoelectric vibrating body of the present invention, the piezoelectric element and the reinforcing member are laminated and bonded to each other, a bonding surface of the piezoelectric element with the reinforcing member, and a bonding surface of the reinforcing member with the piezoelectric element. Are different in size, and it is preferable that one of the joining surface of the piezoelectric element and the joining surface of the reinforcing member extends outside the other.

  According to the present invention, since the bonding surface of the piezoelectric element and the bonding surface of the reinforcing member are inconsistent in size, the metal bonding material is held on one of the bonding surfaces that extends outward. Is possible. With such a configuration, the flux in the metal bonding material discharged from between the piezoelectric element and the reinforcing member without being alloyed with the counterpart material can be held on the extended bonding surface. It is possible to prevent the vibration characteristics from being shifted due to the outflow. Further, since flux can be prevented from flowing into the gap between each of the piezoelectric element and the reinforcing member and the positioning jig, the flux does not adhere between the piezoelectric vibrator and the jig, and the piezoelectric vibrator is removed from the jig. It can be easily removed.

  Here, the flux contained in the metal bonding material refers to a member that connects the mating material and the bonding material (for example, Sn) in the metal bonding material forming the alloy layer to each other. Usually, the flux is non-conductive. A member is included. Such flux outflow is prevented, and the flux does not go around to the surface opposite to the piezoelectric element reinforcement member. Therefore, connect the probe to the electrode formed on the surface opposite to the piezoelectric element reinforcement member. When conducting the inspection, continuity failure does not occur and this electrode inspection is not hindered.

  In the piezoelectric vibrating body of the present invention, the piezoelectric element and the reinforcing member are each formed as a plate-like member having different plane dimensions, and the piezoelectric element and the reinforcing member are laminated and joined in the thickness direction. Is preferred.

According to the present invention, only one of the piezoelectric element and the reinforcing member is formed large, and one of the bonding surfaces of the piezoelectric element and the reinforcing member extends to the outside of the other bonding surface. The configuration can be easily formed. With this configuration, one of the bonding surface of the piezoelectric element and the bonding surface of the reinforcing member that extends outward and the side surface of the piezoelectric element that intersects the bonding surface or the side surface of the reinforcing member are provided with metal. It becomes possible to hold the bonding material (including the flux).
The piezoelectric element can be easily formed by dicing or the like, and the reinforcing plate can be easily formed by press punching or wire cutting.

  In the piezoelectric vibrating body of the present invention, the piezoelectric element and the reinforcing member are each plate-shaped and laminated and bonded together in the thickness direction, and one bonding surface of the piezoelectric element and the reinforcing member and the other It is preferable that the one joining surface is formed larger than the other joining surface by forming an acute angle with the side surface.

  That is, the other side surface forming an acute angle with the one joint surface is formed obliquely with respect to the thickness direction of the piezoelectric element or the reinforcing member, and from the position where the one joint surface intersects the other side surface. One joint surface extends outward. Such an oblique side surface can be formed by, for example, oblique dicing.

According to the present invention, by forming the side surface of the piezoelectric element or the side surface of the reinforcing member obliquely, while making a dimension mismatch portion (the extending portion) between the bonding surface of the piezoelectric element and the bonding surface of the reinforcing member, Since the positions of the edge portions of the piezoelectric element and the reinforcing member can be made uniform, positioning when joining the piezoelectric element and the reinforcing member is facilitated.
In the present invention, it is possible to hold the metal bonding material (including the flux) on both the one joint surface extending outward and the other side surface formed obliquely.

  In the piezoelectric vibrating body of the present invention, the piezoelectric element and the reinforcing member are each plate-shaped and laminated and bonded to each other in the thickness direction, and the bonding surface of the other of the piezoelectric element and the reinforcing member and the other It is preferable that the one joining surface is formed to be larger than the other joining surface by forming an indented stepped portion at a corner formed by the side surface.

That is, the stepped portion in the shape of a corner faces one joining surface, and one joining surface extends outward from the position where the stepped portion faces. Such a step portion can be formed by so-called step cut or the like.
Also according to the present invention, it is possible to make the positions of the respective edge portions of the piezoelectric element and the reinforcing member uniform while forming a dimensional mismatch portion (the extending portion) between the bonding surface of the piezoelectric element and the bonding surface of the reinforcing member. Since it becomes possible, positioning at the time of joining a piezoelectric element and a reinforcement member becomes easy.
In the present invention, it is possible to hold the metal bonding material (including flux) on both the one joint surface extending outward and the inside of the stepped portion.

  In the piezoelectric vibrating body of the present invention, it is preferable that a gap material having a melting point higher than the melting point of the metal bonding material is provided between the bonding portion of the piezoelectric element and the bonding portion of the reinforcing member.

According to the present invention, the gap material is not melted at the time of joining, and flux or the like is accumulated in the gap between the piezoelectric element formed by the gap material and the reinforcing member, so that the flux or the like can be prevented from flowing out. As a result, it is possible to prevent a shift in vibration characteristics and adhesion of the metal bonding material to the jig.
In addition, workability | operativity can be made favorable by mixing a gap material in a metal joining material previously.

The application of the above piezoelectric vibrator is not particularly limited, and the piezoelectric vibrator of the present invention is widely used as electronic parts such as an oscillator, a filter, and a transformer, a sensor, a piezoelectric actuator (ultrasonic motor), and a piezoelectric buzzer. Available.
The type of driving the driven body by vibration (ultrasonic motor), regardless of the driving method of the piezoelectric actuator, is, for example, a standing wave driving method in which the position of the vibration node and the antinode is unchanged, the node and antinode A traveling wave driving method in which the position of the transition is appropriately adopted. Further, the polarization direction of the piezoelectric element, the direction of voltage application, and the like can be arbitrarily configured.
As the driven body, a rotor that is rotationally driven, a linear driven body that is linearly driven, or the like can be employed.

An electronic apparatus according to the present invention includes the above-described piezoelectric vibrating body and a driven body driven by the vibration of the piezoelectric vibrating body.
According to the present invention, since the piezoelectric vibrator described above is provided, the same operations and effects as described above can be enjoyed.
Here, the present invention is applicable to various electronic devices such as a camera, a printer, a portable information device, a movable toy, and a measuring device. The piezoelectric vibrator described above is incorporated as a driving device or an oscillator in these electronic devices.

  The electronic device of the present invention is a timepiece including a timekeeping unit that performs timekeeping and a timekeeping information display unit that displays timekeeping information by the timekeeping unit, and the driven body drives the timekeeping information display unit. It is preferable that it is a body.

  According to the present invention, it is possible to display the time information such as the time and the calendar by transmitting the vibration of the piezoelectric vibrating body to the rotor or the like to drive the gear or the like. Since the above-mentioned piezoelectric vibrator has significantly improved heat dissipation, it is particularly preferable to drive a heavy member with a large load by applying a large amount of power or continuously driving a second hand, etc. Can do. Moreover, since the long-term reliability of joining is high and peeling between the piezoelectric element and the reinforcing member does not occur, the reliability of the product can be improved. In addition, since the process of joining the piezoelectric element and the reinforcing member is not complicated, the manufacturing cost can be reduced.

  The method for manufacturing a piezoelectric vibrating body of the present invention includes a joining step of joining a piezoelectric element having a metal film and a reinforcing member that reinforces the piezoelectric element, and a joint portion of the piezoelectric element with the reinforcing member is a metal. In the joining step, the joining portion with the piezoelectric element in the reinforcing member is constituted with a metal coating or the oxide film of the joining portion is removed. The piezoelectric element and the reinforcing member are bonded with a metal bonding material.

  Here, by forming a metal film having good wettability with solder on the piezoelectric element and forming a metal film with good wettability with solder on the reinforcing member or removing the oxide film, the piezoelectric element and the reinforcing member are formed. Is securely joined.

According to the present invention, the heat of the piezoelectric element is radiated to the reinforcing member via the metal bonding material between the piezoelectric element and the reinforcing member, and further sufficiently dissipated to the device housing to which the reinforcing member is fixed. Therefore, the characteristics of the piezoelectric element are stabilized, and reliability can be ensured.
Also, since the piezoelectric element surface and the metal bonding material, and the metal bonding material and the reinforcing plate surface are bonded to each other, a higher bonding force can be obtained than in the case of adhesion based on intermolecular force, and long-term reliability of bonding Can be secured.

Furthermore, since the metal bonding material comes into full contact with each of the piezoelectric element and the reinforcing member by the bonding, and the piezoelectric element and the reinforcing member are conducted through the metal bonding material, the conduction is extremely stable, and the electrical Stable conduction resistance can be obtained.
And in this invention which joins, since a manufacturing process becomes simple, manufacturing efficiency can be improved.
As described above, according to the present invention, any of (Problem 1) to (Problem 3) can be solved.

  In the method for manufacturing a piezoelectric vibrator of the present invention, in the joining step, either the joint in the reinforcing member or the joint in the piezoelectric element is selected by any one of screen printing, solder plating, and solder foil arrangement. It is preferable to supply the metal bonding material and not supply the metal bonding material to the portions other than the respective bonding portions.

  According to the present invention, the metal bonding material can be easily and surely supplied only to a necessary portion by any one of screen printing, plating, and disposition of the foil-shaped metal bonding material.

  The piezoelectric vibrator manufacturing apparatus of the present invention includes a jig provided on a piezoelectric element and a reinforcing member that is laminated and bonded to the piezoelectric element, and the jig is a bonding surface of the piezoelectric elements to be bonded to each other. And a mounting portion for mounting the piezoelectric element and the reinforcing member, and a hanging portion extending downward from the mounting portion along a direction substantially orthogonal to the bonding surfaces. And the drooping part is disposed in the vicinity of the outer edge part of the piezoelectric element or the reinforcing member that is in contact with the placement part and at the inner side of the outer edge part. Features.

  According to the present invention, by forming the hanging portion, the contact area between the piezoelectric element and the reinforcing member and the mounting portion can be reduced while mounting the piezoelectric element and the reinforcing member. At the time of joining the piezoelectric element and the reinforcing member, flux or the like flowing from between the piezoelectric element and the reinforcing member is guided to the hanging part, so that flux or the like is generated in the gap between the mounting part and the piezoelectric element or reinforcing member. Does not flow. For this reason, it can be prevented that the piezoelectric vibrating body cannot be removed from the mounting portion due to fixation of flux or the like.

  The method for manufacturing a piezoelectric vibrating body of the present invention includes a jig provided on a piezoelectric element and a reinforcing member that is laminated and bonded to the piezoelectric element, and the jig is a bonding surface of the piezoelectric elements that are bonded to each other. And a mounting portion for mounting the piezoelectric element and the reinforcing member, the contact portion being in contact with the piezoelectric element or the reinforcing member. There is a non-contact portion that is recessed below the contact portion and does not contact the piezoelectric element or the reinforcing member.

Here, in order to form a non-contact part and a contact part, a groove | channel, a slit, etc. should just be formed in a mounting part.
According to this invention, by forming the contact portion and the non-contact portion, respectively, the contact area between the piezoelectric element and the reinforcing member and the placement portion can be reduced while placing the piezoelectric element and the reinforcement member. With such a configuration, since flux or the like flowing from between the piezoelectric element and the reinforcing member is guided to the non-contact portion, it is possible to prevent the piezoelectric vibrating body from being unable to be removed from the placement portion due to fixation of the flux or the like.

According to the present invention as described above, the heat dissipation of the piezoelectric element is remarkably improved by the joining, so that the characteristic deterioration due to self-heating of the piezoelectric element can be prevented, and the downsizing of the device can be promoted.
In addition, the long-term reliability of bonding can be greatly improved by bonding with a metal bonding material.
Further, since the metal bonding material comes into full contact with each of the bonding portion in the piezoelectric element and the bonding portion in the reinforcing member, and the piezoelectric element and the reinforcing member are conducted through the metal bonding material, a simple bonding process is performed. However, the conduction between the piezoelectric element and the reinforcing member can be extremely stabilized.

Hereinafter, each embodiment of the present invention will be described with reference to the drawings. Hereinafter, as an embodiment of the electronic device, an electronic timepiece incorporating a piezoelectric actuator and a printer (tenth embodiment) will be exemplified.
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.

[First Embodiment]
A first embodiment of the present invention will be described with reference to FIGS. In the present embodiment, a watch equipped with a date display function is shown as an application example of a piezoelectric actuator.
[1. overall structure]
FIG. 1 is an external view of an electronic timepiece 1 according to the present embodiment. The electronic timepiece 1 includes a movement 141 as a timekeeping portion and a dial 142, hour hand 143, minute hand 144 and second hand 145 as a timekeeping information display portion for displaying hour, minute and second, as well as a window provided on the dial 142. This is a watch provided with a date display device 70 for displaying the date from the section 142A.

[2. Configuration of date display device]
FIG. 2 is a plan view showing the date display device 70 supported by the bottom plate 141A. The date display device 70 includes a piezoelectric actuator 20, a rotor 28 that is driven to rotate by the piezoelectric actuator 20, a reduction wheel train 71 that transmits the rotation of the rotor 28 while reducing the rotation, and a reduction wheel train 71. And a date wheel 72 that is rotated by the driving force transmitted through it.
The rotor 28 is a drive body that drives the date wheel 72 via the speed reduction wheel train 71 by being driven to rotate by the piezoelectric actuator 20 at the turn of the day or at the time of date correction. In the present embodiment, a spring member 281 that biases the rotor 28 toward the piezoelectric vibrating body 20A of the piezoelectric actuator 20 is provided.
The reduction wheel train 71 includes a gear 711 that is disposed coaxially with the rotor 28 and rotates integrally with the rotor 28, a date turning intermediate wheel 712 that meshes with the gear 711, and a date turning wheel 713.

  Below the bottom plate 141A (behind) is a stepping motor (not shown) that is operated by a pulse signal oscillated by the crystal resonator, and a hand movement that is connected to the stepping motor and drives the hour hand 143, the minute hand 144, and the second hand 145. A train wheel (not shown), a battery 141B, and the like are provided. The battery 141B supplies power to each circuit such as a stepping motor, the piezoelectric actuator 20, and a drive circuit (not shown) that applies an AC voltage to the piezoelectric actuator 20.

  The date indicator driving intermediate wheel 712 includes a large-diameter portion 712A and a small-diameter portion 712B. The small-diameter portion 712B is a cylindrical shape having a slightly smaller diameter than the large-diameter portion 712A, and a substantially square-shaped notch 712C is formed on the outer peripheral surface thereof. The small diameter portion 712B is fixed so as to be concentric with the large diameter portion 712A. Since the gear 711 on the upper portion of the rotor 28 is engaged with the large diameter portion 712 </ b> A, the intermediate date indicator driving wheel 712 rotates in conjunction with the rotation of the rotor 28.

  A leaf spring 714 is provided on the bottom plate 141A on the side of the intermediate date wheel 712. A base end portion of the leaf spring 714 is fixed to the bottom plate 141A, and a distal end portion is bent into a substantially V shape. Has been. The front end of the leaf spring 714 is provided so as to be able to enter and leave the notch 712C of the intermediate date wheel 712. A contact 715 is disposed at a position close to the leaf spring 714, and this contact 715 is moved when the intermediate date wheel 712 rotates and the tip of the leaf spring 714 enters the notch 712C. It comes into contact with the spring 714. A predetermined voltage is applied to the leaf spring 714, and when the leaf spring 714 contacts the contact 715, the voltage is also applied to the contact 715. Therefore, by detecting the voltage of the contact 715, the date feeding state can be detected, and the amount of rotation of the date wheel 72 for one day can be detected.

  The rotation amount of the date wheel 72 is not limited to that using the leaf spring 714 or the contact 715, but the rotation amount of the rotor 28 or the date indicator driving intermediate wheel 712 is detected and a predetermined pulse signal is output. Specifically, various rotary encoders such as known photo reflectors, photo interrupters, and MR sensors can be used.

  The date wheel 72 has a ring shape, and an internal gear 721 is formed on the inner peripheral surface thereof. The date indicator driving wheel 713 has a five-tooth gear and meshes with an internal gear 721 of the date indicator 72. A shaft 713A is provided at the center of the date driving wheel 713, and the shaft 713A is loosely inserted into a through hole 141C formed in the bottom plate 141A. The through hole 141 </ b> C is formed long along the circumferential direction of the date indicator 72. The date indicator driving wheel 713 and the shaft 713A are urged in the upper right direction in FIG. 2 by a leaf spring 713B fixed to the bottom plate 141A. The bias of the leaf spring 713B prevents the date wheel 72 from swinging.

[3. Configuration of piezoelectric actuator]
The piezoelectric actuator 20 is activated at a date change or at the time of date correction, and drives the rotor 28 by being supplied with an AC voltage by a drive circuit (not shown).
FIG. 3 shows the piezoelectric actuator 20. 4 and 5 are a sectional view taken along line IV-IV and a sectional view taken along line VV in FIG. In FIGS. 4 and 5, the thickness of the electrode layer and the like is exaggerated for easy understanding of the structure.
The piezoelectric actuator 20 is configured by a piezoelectric vibrating body 20A having a substantially rectangular plate shape as a whole. Note that a lead substrate 27 (FIG. 9) is provided on the piezoelectric vibrating body 20A.
The piezoelectric vibrating body 20A includes two rectangular plate-shaped piezoelectric elements 21 and 21 and a reinforcing plate 22 that holds these piezoelectric elements 21 and 21. The piezoelectric elements 21 and 21 are laminated on the front surface and the back surface of the reinforcing plate 22, respectively, and the piezoelectric elements 21 and 21 and the reinforcing plate 22 are joined by solder as a metal joining material.
In this embodiment, the metal bonding material for bonding the piezoelectric elements 21 and 21 and the reinforcing plate 22 includes gold brazing (Au / Ag / Cu / Zn / In), silver brazing (Ag / Cu / Zn / Sn5). ), Copper brazing, phosphor copper brazing (Cu / P / Sn), nickel brazing (Ni / Si / P), palladium brazing (Pd / Ag / Cu), and the like.

[3-1. Configuration of piezoelectric element]
In this embodiment, lead zirconate titanate (PZT (registered trademark)) is used for each piezoelectric element 21 and is polarized in the thickness direction. The Curie point of PZT is about 300 to 400 ° C. In addition to this PZT, crystal, lithium niobate, barium titanate, lead titanate, lead metaniobate, polyvinylidene fluoride, lead zinc niobate, lead scandium niobate, and the like can be used as the piezoelectric element 21. The polarization directions of the piezoelectric elements 21 and 21 are symmetric with respect to the thickness direction with the reinforcing plate 22 interposed therebetween.
Note that the dimensions of the piezoelectric element 21 in the present embodiment are a width of 1 mm, a length of 3.5 mm, and a thickness of 0.15 mm.

On the surface of each piezoelectric element 21, for example, five electrodes 211 to 215 are formed by ion plating classified as vapor deposition among vapor phase surface treatment techniques. During the ion plating process, a metal mask corresponding to the shape of the electrodes 211 to 215 is used. The thickness of the metal mask is 0.05 mm, for example. Note that the method of forming the electrodes 211 to 215 is not limited to this. For example, the electrodes 211 to 215 are formed by dividing the entire surface electrode formed on the entire surface of the piezoelectric element 21 by electroplating or the like by etching or the like. Also good.
These electrodes 211 to 215 are formed in the same shape at the same position with the reinforcing plate 22 between the piezoelectric elements 21 and 21. That is, in one piezoelectric element 21 disposed on the upper side of the reinforcing plate 22 in FIG. 3, an electrode 213 is formed along the longitudinal direction in a region including the plane center of the piezoelectric element 21, and the piezoelectric element 21 Electrodes 211, 215 and electrodes 212, 214, which are respectively point-symmetric with respect to the plane center, are formed. Similarly, the other piezoelectric element 21 disposed below the reinforcing plate 22 in FIG. The electrode 213 is formed along the longitudinal direction in a region including the plane center of the piezoelectric element 21, and the electrodes 211 and 215 and the electrodes 212 and 214 that are point-symmetric with respect to the plane center of the piezoelectric element 21, respectively. And are formed respectively.

On the other hand, although not shown in FIG. 3, as shown in FIG. 4, plating, sputtering, vapor deposition, etc. over almost the entire surface of each piezoelectric element 21 opposite to the side where the electrodes 211 to 215 are formed. The electrode 210 as a metal film is formed by any of the methods described above, and this electrode 210 is electrically connected to the reinforcing plate 22 through the solder layer 30. The reinforcing plate 22 also functions as an electrode of the piezoelectric element 21.
The electrode 210 has a base layer made of Ni or Ni alloy having a thickness of about 1.0 μm and a surface layer film having good wettability with solder made of Au or Au alloy having a thickness of about 0.1 μm. The surface coating of the electrode 210 is not limited to Au or an Au alloy coating, but may be an alloy of Pd and Ag, Ni, Cu, or the like. However, when the surface layer coating of the electrode 210 is a metal that is very easily oxidized, such as Ni or Cu, handling in an inert atmosphere, for example, an N ₂ atmosphere is required.
In the present embodiment, Sn 42% and Bi 58% cream solder is used as the solder of the solder layer 30, and the melting point of this solder is 139 ° C. However, the present invention is not limited to this, and various solders such as Sn—Ag—Cu, Sn—Cu, Pb—Ag, Sn—Bi, and Sn—Pb alloys can be used. In addition, the thickness of the solder layer 30 in this embodiment is about 10.0 μm.

[3-2. Reinforcement plate configuration]
Returning to FIG. 3, the reinforcing plate 22 is formed of SUS301 in the present embodiment, and has a substantially rectangular reinforcing plate body 221 that is a portion on which the piezoelectric elements 21 are stacked, and each short side portion of the reinforcing plate body 221. And a pair of support portions 223 and 223 provided on each of the long side portions of the reinforcing plate main body 221. The reinforcing plate main body 221, the projecting portions 222A and 222B, and the support portion 223 are integrally formed by a press.
Here, the reinforcing plate 22 is formed of a base material (pre-plated material) on which a metal film having Au as a surface layer is formed on each of the front surface and the back surface. That is, as shown in FIG. 6, each reinforcing plate 22 is formed by punching out from the base material 22X with a press. For this reason, the metal film is not formed on the side surface 22L of the reinforcing plate 22, and the SUS301 substrate is exposed. When pressing, the area around the reinforcing plate 22 is punched in several places.
As shown in FIGS. 4 and 5, electrodes 220 and 220 as metal films are formed on the front and back surfaces of the reinforcing plate 22 pressed from the pre-plated material as described above.

  The protrusion 222A is set in a relative position with the rotor 28 so as to come into contact with the outer peripheral surface of the rotor 28 (FIG. 2) with a predetermined force, and between the protrusion 222A and the side surface of the rotor 28. By generating an appropriate frictional force, the vibration of the piezoelectric vibrating body 20 </ b> A is transmitted to the rotor 28. The protrusion 222A may be formed of a member different from the reinforcing plate body 221. The other protrusion 222B is provided as a counter.

Each support portion 223 has a constricted portion 223A provided continuously with the reinforcing plate body 221 and a fixing portion 223B fixed to the bottom plate 141A (FIG. 2) with screws, and supports the piezoelectric element 21. A fixing hole 223C through which a screw is inserted and a positioning hole 223D are formed in the fixing portion 223B.
The constricted portions 223A of the support portions 223 are provided on both sides in the width direction of the piezoelectric vibrating body 20A in the vicinity of the position of the vibration node (the center of the plane of the piezoelectric vibrating body 20A) in the piezoelectric vibrating body 20A.

Here, insulating members 220Z made of epoxy insulating resin are disposed on the surfaces of the support portion 223 and the protrusions 222A and 222B, respectively. Each insulating member 220Z is formed on the support portion 223 and the protrusions 222A and 222B, respectively. Specifically, the insulating member 220Z in the protrusions 222A and 222B is formed on the entire protrusions 222A and 222B, and the insulating member 220Z in the support part 223 is formed on the constricted part 223A. Each insulating member 220 </ b> Z is printed on the surface of the electrode 220.
Since these insulating members 220Z are not wetted with solder, each insulating member 220Z functions as a bonding material non-adhering portion. As shown in FIG. 5, each insulating member 220 </ b> Z is formed to have a thickness equal to or greater than the thickness of the solder layer 30.

[3-3. Structure of the junction between the piezoelectric element and the reinforcing plate]
FIG. 7 is an exploded perspective view of the piezoelectric vibrating body 20 </ b> A and shows the joint surfaces of the piezoelectric elements 21 and 21 and the reinforcing plate 22. That is, the piezoelectric element 21 and the reinforcing plate 22 are joined by solder (not shown) using the surface on which the electrode 210 is formed and the surface on which the electrode 220 is formed as respective joining surfaces.
In the present embodiment, the electrode 210 of the piezoelectric element 21 is formed on the entire bonding surface of the piezoelectric element 21, and the electrode 220 of the reinforcing plate 22 is also formed on the entire bonding surface of the reinforcing plate 22. Here, the joint between the piezoelectric element 21 and the reinforcing plate 22 is an electrode 210, and the joint with the piezoelectric element 21 in the reinforcing plate 22 is an electrode 220.

[4. Electrical configuration of piezoelectric actuator]
FIG. 8 is a conceptual diagram of the electrical configuration of the piezoelectric actuator 20. The electrodes 211 to 215 provided on the piezoelectric element 21 are connected to the drive circuit 20 </ b> X via the lead substrate 27. On the other hand, the reinforcing plate 22 is connected to the drive circuit 20X by a lead wire (not shown) provided in the fixing portion 223B (FIG. 3).
The reinforcing plate 22 is connected to the GND as an electrode common to the piezoelectric elements 21 and 21, and between the electrodes 211 to 215 of the one piezoelectric element 21 and the reinforcing plate 22 and the other piezoelectric element 21 by the drive circuit 20 </ b> X. An AC voltage is applied between each of the electrodes 211 to 215 and the reinforcing plate 22. In addition, although each electrode 211-215 is selectively used so that it may mention later, the same electrodes provided in each piezoelectric element 21, ie, electrodes 211 and 211, electrodes 212 and 212, electrodes 213 and 213, and electrode 214, respectively. 214 and electrodes 215 and 215 are simultaneously applied with the same potential.

  The drive circuit 20X is mounted on a main board (not shown), and includes a voltage application unit that applies an AC voltage to the piezoelectric elements 21 and 21, and a vibration detection unit that detects the vibration state of the piezoelectric vibrating body 20A. The drive circuit 20 </ b> X is provided with a selector that energizes each of the electrodes 211 to 215 to either the voltage application device or the vibration detection device according to the rotation direction of the rotor 28. The waveform of the voltage applied by the voltage application unit of the drive circuit 20X is not particularly limited, and for example, a sine wave, a rectangular wave, a trapezoidal wave, or the like is employed.

In the present embodiment, the phase of the drive signal oscillated by the voltage application unit of the drive circuit 20 </ b> X is a single phase, and the electrodes 211 to 215 and the reinforcing plate 22 are supplied with drive signals having the same phase.
Here, in the piezoelectric vibrating body 20A, the length ratio and thickness of the vertical and horizontal dimensions of the piezoelectric elements 21 and 21 are such that the protrusion 222A (FIG. 9) draws a good vibration locus and the rotor 28 can be driven with high efficiency. The frequency of the drive voltage is set for the piezoelectric vibrating body 20A designed in this way. This drive frequency is set so that the resonance point of longitudinal vibration and the resonance point of bending vibration are close to each other when the piezoelectric vibrating body 20A vibrates.

[5. Operation of piezoelectric actuator]
The operation of the piezoelectric actuator 20 will be described with reference to FIG.
In the piezoelectric actuator 20 of the present embodiment, by properly using the electrodes 211 to 215, the rotor 28 (FIG. 2) is driven in the forward direction R + or the reverse direction R− to drive the date wheel 72 (FIG. 2) in the forward and reverse directions. It is possible to drive in either direction.
A potential is applied to the electrode 213 extending in the longitudinal direction at the approximate center of the piezoelectric element 21 when the rotor 28 rotates in the forward direction R + and in the reverse direction R−. In addition, a potential is applied to the electrodes 211 and 215 arranged on one diagonal line only when the rotor 28 rotates in the positive direction R +, and the rotor 28 is applied to the electrodes 212 and 214 arranged on the other diagonal line. A potential is applied only during rotation in the positive direction R-.
Note that the electrodes 211 and 215 or the electrodes 212 and 214 to which no potential is applied are used as detection electrodes for extracting the vibration state of the piezoelectric actuator 20 as a voltage signal in accordance with forward and reverse rotation of the rotor 28. The vibration detection signal is detected as a differential signal which is a difference between the potentials of the electrodes 211 and 215 with respect to the reference signal or a difference between the potentials of the electrodes 212 and 214 with respect to the reference signal, using the potential of the reinforcing plate 22 as a reference signal.

Specifically, when the rotor 28 is rotated in the positive direction R +, a potential is applied to the electrode 213 and the electrodes 211 and 215, and the piezoelectric elements 21 and 21 are longitudinal in the region of these electrodes 211, 213, and 215. The piezoelectric vibrating body 20A excites longitudinal primary vibration along the longitudinal direction. At this time, due to the arrangement of the electrodes 211 and 215, a moment is generated clockwise in FIG. 9 about the plane center of the piezoelectric vibrating body 20A, and the piezoelectric vibrating body 20A induces a bending secondary vibration that is bent and displaced in the width direction. . The piezoelectric actuator 20 excites in a mixed mode in which the longitudinal vibration and bending vibration are synthesized. Due to the phase difference between the longitudinal vibration and the bending vibration, the protrusion 222A draws an elliptical orbit +, and the rotor 28 (FIG. 2) is driven in the positive direction R + in a direction tangential to the elliptical orbit +. The date wheel 72 is driven to rotate in the forward direction through the rotation of the rotor 28.
At this time, the electrodes 212 and 214 are connected to the vibration detection unit of the drive circuit 20X, and the frequency of the drive voltage output from the voltage application unit of the drive circuit 20X is based on the vibration state detected from the electrodes 212 and 214. Variablely controlled.

On the other hand, when the rotor 28 is rotated in the reverse direction, a potential is applied to the electrode 213 and the electrodes 212 and 214, and the electrodes 211 and 215 are connected to the vibration detection unit of the drive control device.
Here, due to the arrangement of the electrodes 212 and 214, a moment is generated in the piezoelectric vibrating body 20 </ b> A counterclockwise in FIG. 9, and the protrusion 222 </ b> A draws an elliptical orbit. Thereby, the rotor 28 is rotationally driven in the reverse direction R-, and the date indicator 72 is rotationally driven in the reverse direction.

[6. Method for manufacturing piezoelectric vibrator]
Next, a method for manufacturing the piezoelectric vibrating body 20A will be described. The piezoelectric element 21 and the reinforcing plate 22 are respectively prepared in advance. In the case of the piezoelectric element 21, after forming the electrode 210 and the electrodes 211 to 215 on a PZT base material having a thickness of 0.15 mm, the base material is diced to manufacture individual piezoelectric elements 21. On the other hand, the reinforcing plate 22 is formed by pressing from a base material 22X which is a pre-plated material of SUS301 as shown in FIG.

The joining process of the piezoelectric element 21 and the reinforcing plate 22 will be described with reference to FIGS.
FIG. 10 shows the bonding surface of the piezoelectric element 21. As described above, the electrode 210 is formed on the bonding surface of the piezoelectric element 21. In this embodiment, the solder 31 is arranged on the surface of the electrode 210 in an island shape by screen printing. That is, a screen (not shown) in which holes are formed in the form of dots is used, and cream-like solder is uniformly supplied to the surface of the electrode 210 through this screen. As a result, as shown in FIG. 10B, the solder 31 rises from the surface of the electrode 210 in accordance with the thickness of the screen (in this embodiment, 0.03 mm).
The placement of the solder 31 by screen printing is performed in the same manner for each of the piezoelectric elements 21 and 21. FIG. 11 shows a mode in which the piezoelectric elements 21 and 21 on which the solder 31 is disposed and the reinforcing plate 22 are laminated.

FIG. 12 shows a process of joining the piezoelectric elements 21 and 21 and the reinforcing plate 22 using the pressurizing device 110 and the heating device 120. In this embodiment, the pressurizing device 110 and the heating device 120 are configured independently, and pressurization by the pressurization device 110 and heating by the heating device 120 are performed at appropriate timings.
The pressurizing device 110 generally includes a lower plate 111 on which the piezoelectric elements 21 and 21 and the reinforcing plate 22 are disposed, an upper plate 112 facing the lower plate 111, and a weight 113 provided on the upper plate 112. Yes.
The upper plate 112 is lowered in parallel with the lower plate 111 by a screw member or the like (not shown), and the piezoelectric elements 21 and 21 and the reinforcing plate 22 are pressed between the lower plate 111 and the upper plate 112.

  The lower plate 111 has a mounting portion 111A on which the piezoelectric elements 21 and 21 and the reinforcing plate 22 are mounted. The mounting portion 111A extends substantially along the joint surfaces of the piezoelectric element 21 and the reinforcing plate 22, and has a plurality of grooves 111B. In the mounting portion 111 </ b> A, the portion of each groove 111 </ b> B is a non-contact portion that does not contact the piezoelectric element 21, and the portion where the groove 111 </ b> B is not formed is a contact portion that contacts the piezoelectric element 21. Here, since the groove 111B is formed in the vicinity of the outer edge portion 21L of the piezoelectric element 21 and at a position in the plane of the piezoelectric element 21, the distance D from the outer edge portion 21L where the piezoelectric element 21 contacts the mounting portion 111A. Is shorter.

The heating device 120 has an arbitrary heat source, and is in contact with a portion of the reinforcing plate 22 that protrudes from the outer peripheral portion of the piezoelectric element 21, for example, the support portion 223. An elastic member 121 is provided on a portion of the heating device 120 that is in contact with the support portion 233.
When the supporting unit 223 is heated by the heating device 120, the solder 31 is melted by heat conduction in the reinforcing plate 22. The heating temperature by the heating device 120 is determined corresponding to 139 ° C., which is the melting point of the solder 31. Since the melting point of the solder 31 is less than half of the Curie point of the piezoelectric element 21, the characteristics of the piezoelectric element 21 do not deteriorate during heating.
Since the reinforcing plate 22 and the piezoelectric element 21 are guided to the position of the solder 31 by the surface tension of the molten solder 31, the relative position between the piezoelectric element 21 and the reinforcing plate 22 is easily determined. In the present embodiment, the self-alignment using the molten solder and the positioning pins 111 </ b> C provided upright on the lower plate 111 are used together for positioning the piezoelectric element 21 and the reinforcing plate 22.

Here, since the base material of the reinforcing plate 22 is exposed on the side surface 22L of the reinforcing plate 22, the solder 31 does not get wet and does not conform to the side surface 22L (see FIG. 11). For this reason, the solder 31 does not flow out to the side surface 22 </ b> L of the reinforcing plate 22 from between the bonded portion (electrode 210) of the piezoelectric element 21 and the bonded portion (electrode 220) of the reinforcing plate 22.
Further, since the distance D is set short, even if the interface between the solder 31 and the electrodes 210 and 220 is alloyed and the flux is discharged, the flux is in the gap between the piezoelectric element 21 and the mounting portion 111A. The inflow distance is the longest and is limited to the distance D. The flux is stored inside the groove 111B.
Furthermore, the solder 31 does not get wet with the insulating member 220Z and does not fit. For this reason, the solder 31 is wetted only by the electrode 210 and the electrode 220 in the reinforcing plate main body 221, and the solder 31 does not protrude from the support portion 223 or the protrusions 222A and 222B.
The piezoelectric element 21 and the reinforcing plate 22 are joined by the solder 31 being alloyed with the electrodes 210 and 220, respectively.

FIG. 32 is an enlarged cross-sectional view showing a state where the piezoelectric element 21 and the reinforcing plate 22 are joined by the pressurizing device 110 and the heating device 120 described above. Here, the molten solder 31 spreads over the entire surface of the surface of the electrode 210 and the surface of the electrode 220, and Sn and Au are metal in each of the surfaces of the solder 31 and the electrode 210 and the surface of the solder 31 and the electrode 220. A bonded alloy layer 31A is formed. That is, the piezoelectric element 21 and the reinforcing plate 22 are firmly bonded using the region where the respective electrodes 210 and 220 are formed as a bonding portion.
Thus, the piezoelectric element 21 and the reinforcing plate 22 are joined via the alloy layer 31A, and the thermal conductivity of Sn is as high as 68 W / m · k. Therefore, the heat generated by the piezoelectric element 21 when the piezoelectric actuator 20 is driven is Heat is efficiently radiated to the reinforcing plate 22 through the alloy layer 31A. Further, heat is radiated from the reinforcing plate 22 to the bottom plate 141A (FIG. 2) and further to the exterior case of the timepiece 1.

[7. Effects of this embodiment]
According to the embodiment described above, the following effects can be obtained.
(1) Regarding the joining of the piezoelectric elements 21 and 21 and the reinforcing plate 22 of the piezoelectric actuator 20, the electrodes 210 having good wettability with the solder on the joint surfaces between the piezoelectric elements 21 and 21 and the reinforcing plate 22, respectively. By forming 220, the piezoelectric element 21 and the reinforcing plate 22 were joined with the solder 31. Thereby, the heat of the piezoelectric element 21 is sequentially radiated to the reinforcing plate 22, the base 12, the housing 4 and the like via the solder 31, so that the problem of self-heating of the piezoelectric element 21 can be solved. Thereby, the characteristic of the piezoelectric element 21 is stabilized and reliability can be ensured.
Further, since the temperature rise of the piezoelectric element 21 is suppressed, it is not necessary to add a heat radiating fin or the like, and the piezoelectric vibrating body 20A can be miniaturized, and the advantage of the piezoelectric actuator 20 that is small and has high power is drawn out. be able to.

(2) Furthermore, since the bonding between the piezoelectric element 21 and the reinforcing plate 22 is microscopically a metal bond, a higher bonding force can be obtained than in the case of bonding based on intermolecular force, and the bonding can be performed for a long time. Reliability can be secured.

(3) Furthermore, unlike the case of the adhesive, since the electrode 210 of the piezoelectric element 21 and the electrode 220 of the reinforcing plate 22 are electrically connected to each other by the solder 31, the conduction is stable and electrically stable. The conduction resistance is obtained.
And in the manufacturing process which joins with the solder 31, since the solder 31 should just be arrange | positioned to the piezoelectric element 21 or the reinforcement board 22 by screen printing, for example, a manufacturing process becomes simple. That is, manufacturing efficiency can be improved.

(4) Since the solder 31 having a melting point much lower than the Curie point of the piezoelectric element 21 is used, it is possible to prevent deterioration of the characteristics of the piezoelectric element 21 due to heating during bonding.

(5) Since the metal film is not formed on the side surface 22L of the reinforcing plate 22, the solder 31 does not flow on the side surface 22L, and the solder 31 is allowed to remain in the joint portion, which is the region where the electrode 220 of the reinforcing plate 22 is formed. be able to.
As described above, since the metal film is not formed on the side surface 22L of the reinforcing plate 22, the solder 31 can be prevented from flowing to the outer peripheral portion of the reinforcing plate 22 through the positioning pin 111C. That is, if the solder 31 adheres to a part of the outer peripheral portion of the reinforcing plate 22, the vibration of the piezoelectric vibrating body 20 </ b> A becomes unbalanced and the vibration characteristics shift, but it is possible to prevent variations in vibration characteristics due to such factors.
Since the pre-plated material is used, it is possible to easily manufacture the reinforcing plate 22 in which the metal film is formed only on the flat portion of the reinforcing plate 22 and the metal film is not formed on the side surface portion.

(6) Since the solder 31 does not flow to the side surface 22L of the reinforcing plate 22, the side surface of the protruding portion 222A can be in a state where the substrate of the reinforcing plate 22 is exposed. Thereby, the uniform frictional resistance between the protrusion 222A and the rotor 28 can be maintained.

(7) Furthermore, since the solder 31 does not flow to the side surface 22L of the reinforcing plate 22, it is possible to prevent the solder 31 from flowing from the side surface of the reinforcing plate 22 to the electrodes 211 to 215 of the piezoelectric element 21. Thereby, it can prevent that the reinforcement board 22 and the electrodes 211-215 short-circuit.

(8) By providing the insulating member 220Z, it is possible to restrict the flow of the solder 31 from the reinforcing plate body 221 toward the support portion 223. As a result, it is possible to more reliably prevent the vibration characteristics from shifting and the vibration characteristics from varying and the short circuit between the electrodes.
Here, since this insulating member 220Z is provided on the surface of the electrode 220, a bonding material non-adhered portion is formed, and therefore masking during electrode formation can be eliminated as in the second embodiment described later.

(9) Since screen printing is adopted as a method of arranging the solder 31 before joining, the solder 31 can be easily supplied only to a necessary portion of the joining surface of the piezoelectric element 21.

(10) Since the groove 111B is formed in the mounting portion 111A of the pressure device 110, and the distance D from the outer edge portion 21L of the piezoelectric element 21 in contact with the mounting portion 111A, the distance D is small. It is possible to suppress the flux that has flowed out between the piezoelectric element 21 and the reinforcing plate 22 from flowing between the mounting portion 111 </ b> A and the piezoelectric element 21. For this reason, even if the flux is fixed, the piezoelectric vibrating body 20A can be easily detached from the mounting portion 111A.

(11) The adoption of the piezoelectric actuator 20 is not affected by magnetism, has high responsiveness, enables fine feed, is advantageous for downsizing and thinning, and has high torque and large holding torque (the rotor position is maintained even when no current is applied) Can be enjoyed).

(12) Further, since the piezoelectric actuator 20 is thin, it is suitable for incorporation into a watch in which thinning is an important issue, and the piezoelectric actuators 21 and 21 are electrically connected in parallel to reduce the thickness. Since a large displacement can be obtained by voltage, the application to the electronic timepiece 1 driven by a battery is particularly suitable.

[Second Embodiment]
Next, a second embodiment of the present embodiment will be described. In this embodiment, the pre-plated material is not used for the reinforcing plate, and the solder is arranged at the joint by a method other than screen printing. Except for these points, the piezoelectric actuator of the present embodiment is configured in the same manner as the piezoelectric actuator 20 of the first embodiment.

FIG. 13 is an exploded perspective view of the piezoelectric actuator 30 of the present embodiment. However, FIG. 13 does not show solder for joining the piezoelectric element 21 and the reinforcing plate 32.
The reinforcing plate 32 of the present embodiment includes a rectangular reinforcing plate main body 321 laminated on the piezoelectric element 21, projecting portions 322A and 322B, and a support portion 323, which are based on SUS301 that is not a pre-plated material. The material is pressed and formed integrally.
In the present embodiment, the electrodes 320 are formed on the front surface and the back surface of the reinforcing plate body 321 by masking the protrusions 322A and 322B and the support portion 323 and performing electroplating or the like. The electrode 320 has a base made of Ni or Ni alloy having a thickness of about 1.0 μm and a coating made of Au or Au alloy having a thickness of about 0.1 μm. The surface layer coating of the electrode 320 is not limited to Au or an Au alloy coating, but may be an alloy of Pd and Ag.
Here, the support portion 323 and the protrusions 322A and 322B are non-coating portions 320X where the substrate of SUS310 is exposed, and the non-coating portions 320X are inferior in wettability with solder than the electrodes 320, so that no bonding material adheres It functions as a part. That is, it is possible to form the bonding material non-adhering portion using the non-coating portion 320X without providing the insulating member 220Z that functions as the bonding material non-adhering portion as in the first embodiment.

  FIG. 14 shows a state in which solder for joining the piezoelectric element 21 and the reinforcing plate is disposed on the reinforcing plate 32. In this embodiment, the coating 33 by solder plating is laminated | stacked on the electrodes 320 and 320 of the surface and back surface of the reinforcement board main body 321, respectively. The reinforcing plate 32 on which the solder plating film 33 is formed and the piezoelectric elements 21 and 21 are sequentially laminated as shown in FIG. 14, and heating and pressing are performed in the same manner as in the first embodiment to perform the piezoelectric element 21. And the reinforcing plate 32 are joined. At this time, since the support portion 323 and the protrusions 322A and 322B are the non-coating portion 320X, the non-coating portion 320X is not wetted with solder and does not become familiar. As a result, the solder of the film 33 stays in the respective regions of the electrode 210 and the electrode 320 as the joint portion, and the solder does not protrude from the support portion 323 and the protruding portions 322A and 322B.

According to this embodiment, in addition to the effects similar to (1) to (4) described in the first embodiment, there are the following effects.
(13) The formation of the non-coating portion 320X can restrict the flow of solder from the reinforcing plate body 321 toward the protrusions 322A and 322B and the support portion 323. As a result, it is possible to prevent the vibration characteristics from shifting and the vibration characteristics from varying, and a short circuit between the electrodes.
Further, since the protrusion 322A is the non-coating part 320X and the base of the reinforcing plate 32 is exposed, uniform frictional resistance between the protrusion 322A and the rotor 28 (FIG. 2) can be maintained.

  Here, although the material of the reinforcing plate 32 of this embodiment is stainless steel, the material of the reinforcing plate 32 in this embodiment is a plastic molding material such as polyimide (280 ° C.), PPS (250 ° C.), PET ( 230 ° C.) (continuous use temperature in parentheses). Since these materials can be molded, the reinforcing plate 32 can be easily manufactured.

[Third Embodiment]
Next, a third embodiment of the present embodiment will be described. In this embodiment, in addition to the support part and protrusion part of a reinforcement board, the non-coating part in which a metal film is not formed is formed also in a part of reinforcement board main body. Further, a non-coating portion where a metal coating is not formed is also formed on a part of the piezoelectric element. Except for these points, the piezoelectric actuator of this embodiment is configured in substantially the same manner as the piezoelectric actuator 30 of the second embodiment.

FIG. 15 is an exploded perspective view of the piezoelectric actuator 40 of the present embodiment. However, FIG. 15 does not show solder for joining the piezoelectric element 21 and the reinforcing plate 32.
An electrode 410 is formed at a joint portion of each piezoelectric element 21 with the reinforcing plate 32, and this electrode 410 is excluded from the vicinity of the protrusions 322 A and 322 B of the reinforcing plate 32 and the vicinity of the support portion 323. Formed in the region. As a result, each piezoelectric element 21 has a non-coating portion 410X, which is less wettable with the solder than the electrode 410, at a position near the protrusions 322A and 322B and a position near the support portions 323 and 323, respectively. Is formed.

  In addition, electrodes 420 and 420 are formed at the joint portions of the reinforcing plate 32 with the piezoelectric elements 21 and 21, respectively. The electrodes 420 include the supporting portion 323, the protruding portions 322 A and 322 B, and the protruding portions of the reinforcing plate main body 321. It is formed in a region excluding the positions 321A and 321A in the vicinity of 322A and 322B and the positions 321B and 321B in the vicinity of the support portions 323 and 323 in the reinforcing plate main body 321. Each region where the electrode 420 is not formed is a non-coating portion 420X that is less wettable with solder than the electrode 420, and the non-coating portion 420X is formed on the reinforcing plate 32 in the second embodiment. In addition to the region of the non-coating portion 320X, the reinforcing plate body 321 is formed to include the vicinity positions 321A and 321A of the protrusions 322A and 322B and the vicinity positions 321B and 321B of the support portion 323.

FIG. 16 is a diagram in which solder 31 is arranged at the joint in the piezoelectric element 21. In the present embodiment, the solder 31 is arranged on the piezoelectric element 21 by screen printing as in the first embodiment. Note that the holes of the screen where the solder 31 is squeezed are not formed in the portions corresponding to the non-coating portions 410X and 420X.
The piezoelectric elements 21 and 21 on which the solder 31 is disposed and the reinforcing plate 32 are laminated, and the piezoelectric element 21 and the reinforcing plate 32 are joined by heating and pressing in the same manner as in the first embodiment. At this time, since the non-coating portions 410X and 420X are formed, the solder does not flow from the electrodes 410 and 420 as the joint portions toward the support portion 323 and the projection portions 322A and 322B.

According to this embodiment, in addition to the effects substantially similar to those of the second embodiment, the following effects can be obtained.
(14) The non-coating portion 420X is formed to include the positions 321A and 321A in the vicinity of the protrusions 322A and 322B in the reinforcing plate body 321 and the positions 321B and 321B in the vicinity of the support portion 323. It is possible to more reliably regulate the protrusion of solder from the positions 321B and 321B to the vicinity of the support portion 323 from 321.

[Modification of Third Embodiment]
Here, FIGS. 17 and 18 show a modification of the third embodiment.
In the third embodiment, as shown in FIG. 15, regions where the metal coating is not formed (non-coating portions 410 </ b> X and 420 </ b> X) are formed on both the joining surface of the piezoelectric element 21 and the joining surface of the reinforcing plate body 321. However, as shown in FIG. 17, the non-coating portion 410 </ b> X may be formed only on the bonding surface of the piezoelectric element 21, and the electrode 320 may be formed on the entire bonding surface of the reinforcing plate body 321. Even with such a configuration, since the protrusion of the solder can be restricted by the non-coating portion 410X, the same effect as in the third embodiment can be obtained.
In contrast to FIG. 17, as shown in FIG. 18, the non-coating portion 420 </ b> X may be formed on the joint surface of the reinforcing plate 32, and the electrode 210 may be formed on the entire joint surface of the piezoelectric element 21. Even with such a configuration, since the protrusion of the solder can be restricted by the non-coating portion 420X, the same effect as in the third embodiment can be obtained.

[Fourth Embodiment]
Next, a fourth embodiment of the present embodiment will be described. This embodiment is different from the third embodiment in the position of the non-coating portion formed on the reinforcing plate body. Moreover, the method of arrange | positioning solder to a junction part differs from the said each embodiment. Furthermore, the pressurization heating apparatus different from 1st Embodiment is illustrated. Except for these points, the piezoelectric actuator of the present embodiment is configured in the same manner as the piezoelectric actuator 40 of the third embodiment.

  FIG. 19 is an exploded perspective view of the piezoelectric actuator 45 of the present embodiment. Electrodes 210 are formed on the entire surface of the piezoelectric element 21 where the reinforcing plate 32 is joined. On the other hand, the reinforcing plate body 321 of the reinforcing plate 32 is formed with electrodes 452 having a shape different from that of the third embodiment. Specifically, the electrodes 452 are provided at two locations on each long side portion of the reinforcing plate body 321. Each is formed in a region excluding a total of six locations, one at each short side. Thereby, the non-coating part 452X whose wettability with a solder is inferior to the electrode 452 is formed in six places. The positions of these non-coating portions 452X correspond to the positions of jig pins described later.

  A solder foil 453 is disposed between the piezoelectric elements 21 and 21 and the reinforcing plate 32. The solder foil 453 is formed in a vertical and horizontal dimension that is slightly smaller than the electrode 452, and a notch 453 </ b> A is formed in a portion corresponding to each non-coating portion 452 </ b> X in the reinforcing plate body 321.

FIG. 20 is a schematic view of a pressurizing / heating device that performs pressurization and heating. This pressurizing / heating device includes a pressurizing jig 130 and a plate-like heating member 139.
The pressing jig 130 includes a lower plate 131 and an upper plate 132 each having a rectangular shape in plan view. Pins 133 are erected at the four corners of the lower plate 131, and guide holes 134 for guiding these pins 133 are formed in the upper plate 132. The upper plate 132 is maintained parallel to the lower plate 131 by the pins 133 and the guide holes 134.

  FIG. 21 is a plan view of the lower plate 131. On the lower plate 131, columnar positioning pins (positioning jigs) 135 for defining the relative positions of the piezoelectric elements 21 and 21 and the reinforcing plate 32 are erected. Six of these positioning pins 135 are provided for one piezoelectric actuator 45, and each non-coating portion 452X (FIG. 19) in the reinforcing plate main body 321 described above is positioned at the position of the six positioning pins 135, respectively. Correspondingly formed.

The heating and pressurizing steps in this embodiment are performed as follows. First, the piezoelectric element 21, the solder foil 453, the reinforcing plate 32, the solder foil 453, and the piezoelectric element 21 are sequentially stacked on the lower plate 131 of the pressing jig 130, and the upper plate 132 is disposed thereon.
Then, the pressurizing jig 130 is placed on the heating member 139 that has been heated to about 150 ° C. in advance by an arbitrary heat source, and a preheated weight 136 is placed on the upper plate 132 and heated for about 10 minutes while being pressed. Thus, the piezoelectric element 21 and the reinforcing plate 32 are joined. At this time, since each non-coating portion 452X is formed, the solder does not flow from the electrodes 210 and 420 as the joint portions to the positioning pins 135.

According to this embodiment, in addition to the effects substantially similar to those of the second embodiment, the following effects can be obtained.
(15) Since the non-coating portion 452X is formed in the vicinity of the positioning pin 135 in the reinforcing plate main body 321, the solder does not protrude from the reinforcing plate main body 321 and is restricted from flowing through the positioning pin 135. it can. This can prevent a shift in vibration characteristics, and can also prevent a short circuit between the electrodes. Furthermore, since the flux does not flow between the lower plate 131 and the piezoelectric element 21 through the positioning pin 135, the piezoelectric actuator 45 can be easily detached from the pressure jig 130.

[Modification of Fourth Embodiment]
In the fourth embodiment, as shown in FIG. 19, only the reinforcing plate 32 of the piezoelectric element 21 and the reinforcing plate 32 is formed with the portion (non-coated portion 452X) where the metal coating is not formed. Such a non-coating portion may be formed on both the piezoelectric element 21 and the reinforcing plate 32, or may be formed only on the piezoelectric element 21.

[Fifth Embodiment]
Next, a fifth embodiment of the present invention will be described. In the present embodiment, unlike the above-described embodiments, the size of the bonding surface of the piezoelectric element and the size of the bonding surface of the reinforcing plate are inconsistent. Except for this point, the piezoelectric actuator of the present embodiment is configured in the same manner as the piezoelectric actuator 20 of the first embodiment.

FIG. 22A is a plan view of the piezoelectric actuator 50 of this embodiment, and the piezoelectric actuator 50 includes a piezoelectric element 51 and a reinforcing plate 22.
Here, the piezoelectric element 51 is formed slightly smaller than the reinforcing plate body 221 of the reinforcing plate 22, and the length and width of the piezoelectric element 51 are shorter than the length and width of the reinforcing plate 22, respectively.

FIG. 22B is an end view taken along line BB in FIG. In addition, although electrodes are formed on the joint portion of the piezoelectric element 51 with the reinforcing plate 22 and the joint portion of the reinforcing plate 22 with the piezoelectric element 51, these electrodes are not shown. The same applies to the following FIGS.
The outer peripheral surface 51 </ b> A of the piezoelectric element 51 is arranged to be offset inside the outer peripheral surface 22 </ b> A of the reinforcing plate 22, and the bonding surface 22 </ b> B of the reinforcing plate 22 extends outside the bonding surface 51 </ b> B of the piezoelectric element 51. .
When the piezoelectric element 51 and the reinforcing plate 22 are joined by solder, the flux 31F is guided to the joining surface 22B of the reinforcing plate 22, and the flux 31F is held between the joining surface 22B and the outer peripheral surface 51A of the piezoelectric element 51. Is done.

According to this embodiment, in addition to the same effects as (1) to (4) and the like extended in the first embodiment, the following effects are also obtained.
(16) Since the joining surface of the piezoelectric element 51 is formed smaller than the joining surface of the reinforcing plate 22, the flux 31 </ b> F can be held on the joining surface 22 </ b> B of the reinforcing plate 22 extending outside the piezoelectric element 51. It becomes. As a result, it is possible to avoid problems such as vibration characteristics shifting due to the adhesion of the flux 31F and adhering to the jig.
In addition, since the flux 31F does not go around the surface of the piezoelectric element 51, it is possible to prevent poor conduction when a probe is connected to the electrodes 211 to 215 for inspection.

Here, as a bonding material between the piezoelectric element 51 and the reinforcing plate 22, it is possible to use an adhesive instead of solder. In this case, the bonding surface 22 </ b> B of the reinforcing plate 22 is connected to the piezoelectric element 51 and the reinforcing plate 22. Since it is a liquid storage space for the adhesive protruding from between the two, it has the same effect as the above (16).
However, in this embodiment in which the planar dimensions of the piezoelectric element 51 and the reinforcing plate 22 are different, it is desired to position the piezoelectric element 51 and the reinforcing plate 22 using, for example, stepped pins. Since the adhesive accumulated on the surface 22B adheres to the pins, the positioning of the piezoelectric element 51 and the reinforcing plate 22 becomes difficult.
In that respect, if the solder is used as described above, the relative position in the plane direction between the piezoelectric element 51 and the reinforcing plate 22 is accurately determined by the self-alignment effect of the solder, so that the positioning pin can be dispensed with. That is, the use of solder has an advantage that the relative positions of the piezoelectric element 51 and the reinforcing plate 22 can be accurately defined even if the planar dimensions of the piezoelectric element 51 and the reinforcing plate 22 are different.
The solder self-alignment effect is considered to be caused by the action of the molten solder to reduce its surface area.

[Sixth Embodiment]
Next, a sixth embodiment of the present invention will be described. In this embodiment, contrary to the fifth embodiment, the reinforcing plate is formed smaller than the piezoelectric element.

FIG. 23A is a plan view of the piezoelectric actuator 53 of this embodiment. FIG. 23B is an end view taken along line BB in FIG.
The piezoelectric actuator 53 includes the piezoelectric element 21 and a reinforcing plate 52.
Here, the reinforcing plate 52 includes a reinforcing plate body 521 that is formed slightly smaller than the piezoelectric element 21, projecting portions 222 </ b> A and 222 </ b> B, and a support portion 223. The length and width of the reinforcing plate body 521 are shorter than the length and width of the piezoelectric element 21, respectively.
Note that electrodes (not shown) are formed on the front and back surfaces of the reinforcing plate 52, respectively.

The outer peripheral surface 521A of the reinforcing plate main body 521 is arranged to be offset inside the outer peripheral surface 21A of the piezoelectric element 21, and the bonding surface 21B of the piezoelectric element 21 extends outside the bonding surface 52B of the reinforcing plate 52. . Accordingly, a recess 523 is formed by the bonding surface 21B of one piezoelectric element 21, the outer peripheral surface 521A of the reinforcing plate body 521, and the bonding surface 21B of the other piezoelectric element 21.
When the piezoelectric element 21 and the reinforcing plate 52 are joined by solder, the flux 31F is guided and held in the recess 523.
According to the present embodiment, the same effects as in the fifth embodiment can be obtained.

[Seventh Embodiment]
Next, a seventh embodiment of the present invention will be described. In the present embodiment, the dimensions of the joining surface of the piezoelectric element and the dimensions of the joining surface of the reinforcing plate are inconsistent in a manner different from the fifth and sixth embodiments.

FIG. 24A is a plan view of the piezoelectric actuator 55 of the present embodiment. FIG. 24B is an end view taken along line BB in FIG.
The piezoelectric actuator 55 includes a piezoelectric element 56 and a reinforcing plate 22.
Here, the long side surface and the short side surface of the piezoelectric element 56 are inclined surfaces 56A that form an acute angle with the joint surface 22B of the reinforcing plate 22 by oblique dicing. As described above, since the side surface of the piezoelectric element 56 is the inclined surface 56 </ b> A, the bonding surface 22 </ b> B of the reinforcing plate 22 extends outside the bonding surface 56 </ b> B of the piezoelectric element 56.
When the piezoelectric element 56 and the reinforcing plate 52 are joined by solder, the flux 31F is guided to the joining surface 22B, and the flux 31F is held between the joining surface 22B and the inclined surface 56A.

According to this embodiment, in addition to the same effects as those of the fifth embodiment, the following effects can be obtained.
(17) By forming the side surface of the piezoelectric element 56 as the inclined surface 56A, the edge of the piezoelectric element 56 is formed while forming a dimension mismatch portion (bonding surface 22B) between the bonding surface of the piezoelectric element 56 and the bonding surface of the reinforcing plate 22. Therefore, the positioning of the piezoelectric element 56 and the reinforcing plate 22 can be facilitated.

[Eighth Embodiment]
Next, an eighth embodiment of the present invention will be described. In this embodiment, in a manner different from that of the seventh embodiment, the position of each edge of each of the piezoelectric element and the reinforcing member is determined while creating a dimension mismatching portion between the bonding surface of the piezoelectric element and the bonding surface of the reinforcing member. Aligned.

FIG. 25A is a plan view of the piezoelectric actuator 57 of the present embodiment. FIG. 25B is an end view taken along line BB in FIG.
The piezoelectric actuator 57 includes a piezoelectric element 58 and a reinforcing plate 22.
Here, a stepped portion 58A having a corner shape is formed on the outer peripheral portion of the bonding surface 58B of the piezoelectric element 58 by step cutting. Since the stepped portion 58A is formed in the piezoelectric element 58 in this way, the bonding surface 22B of the reinforcing plate 22 extends outside the bonding surface 58B of the piezoelectric element 58.

When the piezoelectric element 58 and the reinforcing plate 22 are joined by solder, the flux 31F is guided to the joining surface 22B, and the flux 31F is held inside the stepped portion 58A.
According to the present embodiment, the same effects as in the seventh embodiment can be obtained.

[Ninth Embodiment]
Next, a ninth embodiment of the present invention will be described.
FIG. 26 is a cross-sectional view of the piezoelectric actuator 59 of this embodiment. In the present embodiment, a gap material 591 formed of silica (silicon dioxide), glass fiber, plastic, or the like is provided between the piezoelectric element 21 and the reinforcing plate 22. The gap material 591 is mixed in the solder 31 in advance, but since the melting point of the gap material 591 is higher than the melting point of the solder 31, it is not melted at the time of joining. Since the gap G is provided by the gap material 591 between the piezoelectric element 21 and the reinforcing plate 22, the flux 31 </ b> F is held between the bonding surface of the piezoelectric element 21 and the bonding surface of the reinforcing plate 22.

According to the present embodiment, the flux 31F stays in the gap between the piezoelectric element 21 and the reinforcing plate 22 formed by the gap material 591. Therefore, the vibration characteristics shift due to the adhesion of the flux 31F, or are fixed to the jig. Can be avoided.
Moreover, since the flux 31F does not wrap around the surface of the piezoelectric element 21, it is possible to prevent a conduction failure when a probe is connected to the electrodes 211 to 215 (FIG. 22) for inspection.
In addition, the same effects as (1) to (4) extended in the first embodiment are obtained.

[Tenth embodiment]
Next, a tenth embodiment of the present invention will be described.
[1. Overall schematic configuration]
FIG. 27 is a schematic diagram of the printer 7 according to the present embodiment. The printer 7 includes a paper tray 2 on which paper is set, a discharge unit 3 from which printed paper PP is discharged, and a paper feed roller 5 installed inside the housing 4.
The roller 5 sends the paper PP printed by a print driving unit (not shown) to the discharge unit 3.

[2. Paper feed roller drive mechanism]
The drive mechanism for driving the roller 5 transmits the piezoelectric actuator 20 (FIG. 3) similar to that of the first embodiment, the rotor 28 rotated by the vibration of the piezoelectric actuator 20, and the rotation of the rotor 28 while decelerating. The reduction gear train 29 is provided.
Note that all the piezoelectric actuators described above can be incorporated in the printer 7 of the present embodiment.
The reduction gear train 29 includes a gear 291 that is provided coaxially with the rotor 28 and rotates integrally with the rotor 28, and a gear 292 that meshes with the gear 291 and is fixed to the rotation shaft of the roller 5. ing.
The piezoelectric actuator 20 and the rotor 28 are unitized as the piezoelectric actuator unit 10 (FIG. 28).

[3. Configuration of piezoelectric actuator unit]
As shown in FIG. 28, the piezoelectric actuator unit 10 includes a substantially rectangular support plate 11 attached to a frame or the like of the housing 4 (FIG. 27), a piezoelectric actuator 20, and a driven body driven by the piezoelectric actuator 20. And the rotor 28. The piezoelectric actuator unit 10 and the rotor 28 are arranged adjacent to each other in plan view, so that the piezoelectric actuator unit 10 is thin.

Bases 12 and 12 to which the piezoelectric actuators 20 are attached project from the support plate 11, and the piezoelectric actuators 20 are fixedly attached to the bases 12 and 12 by screws 12A, respectively. Each base 12 is formed with positioning pins 12B for mounting and fixing the piezoelectric actuators 20 respectively.
In addition, holes 11A for attaching the support plate 11 to the frame of the housing 4 and screw pins 11B for attaching a cover plate (not shown) are formed at the four corners of the support plate 11, respectively.
Also in this embodiment, since the piezoelectric actuator 20 similar to that in the first embodiment is provided, the same effects as in the first embodiment can be obtained.
In the present embodiment, the heat generated by the piezoelectric element 21 when the piezoelectric actuator 20 is driven and radiated to the reinforcing plate 22 is further transferred from the reinforcing plate 22 to the base 12 (FIG. 28) and further to the housing 4 (FIG. To 27).

In each of the above-described embodiments, piezoelectric actuators of various modes have been shown. FIG. 29 shows a piezoelectric actuator 60 of a mode different from the above-described embodiments.
The piezoelectric actuator 60 differs from the piezoelectric actuators of the above-described embodiments in that the support portion 623 is formed only on one side of the reinforcing plate 62 and drives the rotor 28 in one direction, and the protrusions 622A and 622B are eccentric. That is, the electrode 216 formed on the surface of the piezoelectric element 21 is not divided. Since the bending vibrations are induced by the eccentric positions of the protrusions 622A and 622B, the piezoelectric actuator 60 of the present embodiment also excites elliptical vibrations in the same manner as the piezoelectric actuators of the respective embodiments. Therefore, this piezoelectric actuator 60 can also be incorporated in an electronic timepiece or a printer, like the piezoelectric actuator 20 described above.

[Modification of the present invention]
Although the embodiment of the present invention has been specifically described above, the present invention is not limited to the above-described embodiments, and various improvements and modifications can be made without departing from the gist of the present invention.

  FIG. 30 shows a piezoelectric vibrator manufacturing apparatus (jig) according to the present invention. That is, the hanging portion 111D may be formed on the lower plate 111 instead of the groove 111B formed on the lower plate 111 in FIG. Also here, the distance D from the outer peripheral portion of the piezoelectric element 21 where the piezoelectric element 21 contacts the mounting portion 111A is set short, and the solder is guided downward by the hanging portion 111D, so that the piezoelectric actuator 20 is moved from the mounting portion 111A. It can be easily removed.

In the third embodiment (FIG. 15) and the like, wettability with the solder at the joint portion of the reinforcing plate 32 is obtained by forming the electrode 420 as a metal film on the reinforcing plate 32. In addition, a method of removing the oxide film on the surface of the reinforcing plate 32 by a method such as plasma etching is also conceivable.
In FIG. 31, instead of forming electrodes, the joining surface of the reinforcing plate 32 is processed by plasma etching to remove the oxide film. During this oxide film removal process, a metal mask is provided at positions including the positions 321B and 321B in the vicinity of the support 323 and the positions 321A and 321A in the vicinity of the protrusions 322A and 322B, so that the bonding material non-adhered portion 320Z is formed. Even in this case, on the joint surface of the reinforcing plate 32, a portion 320P having good wettability with solder (a portion subjected to the oxide film removal process) and a portion having poor wettability with solder (joint material non-adhered portion) 320Z), it is possible to prevent the solder from flowing to the support portion 323 and the protrusions 322A and 322B by performing the joining step with the oxide film removed.

  In each of the above-described embodiments, the substantially rectangular piezoelectric vibrator is shown. However, the present invention is not limited to this, and the shape of the piezoelectric vibrator may be an annular shape, a circular shape, a truss shape, a trapezoid shape, or the like.

  Further, in each of the above embodiments, the piezoelectric vibrating body that vibrates when an AC voltage is applied is exemplified, but the present invention can also be applied to a mounting structure of a piezoelectric element to which a DC voltage is applied. As such an example, a piezoelectric valve to which a DC voltage is applied can be cited.

  Furthermore, the layout of the electrodes of the piezoelectric vibrator, the stacking mode of the piezoelectric elements and the reinforcing plate, the number of piezoelectric elements stacked on the reinforcing plate, and the like can be arbitrarily configured. The displacement direction of the piezoelectric element may be appropriately set according to the polarization direction and the direction of the electric field, and is not limited to the piezoelectric lateral effect (each embodiment described above), and may exhibit a piezoelectric longitudinal effect, a piezoelectric thickness shear effect, or the like.

The present invention is not limited to those applied to the printer and the electronic timepiece of the above-described embodiment, and can be applied to various electronic devices, and particularly portable devices that are continuously driven or are small and have high power input. Suitable for electronic devices.
Here, examples of the various electronic devices include a mobile phone, a non-contact IC card, a personal computer, a personal digital assistant (PDA), a camera, a digital camera, and a video camera. When applied to a camera, the piezoelectric vibrating body of the present invention can be used to drive a lens focusing mechanism, a zoom mechanism, a diaphragm adjusting mechanism, and the like.
Furthermore, the driving mechanism of meter pointers for measuring instruments, the driving mechanism of instrument pointers for instrument panels of automobiles, piezoelectric buzzers, piezoelectric vibrators for inkjet heads used in printers, paper feed mechanisms for printers, vehicles, Driving mechanism and posture correction mechanism for movable toys such as dolls, ultrasonic motors, hard disk drives, ultrasonic cleaners, ultrasonic humidifiers, ultrasonic welding / welding devices, ultrasonic therapeutic devices, ultrasonic cutters, tube pumps, etc. Alternatively, the piezoelectric vibrator of the present invention may be used.

  In each of the above embodiments, a wristwatch is shown 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 Karakuri doll or the like.

  In each of the above embodiments, a piezoelectric actuator that uses a piezoelectric element as a driving device has been described. However, the usage range of the piezoelectric element is not limited to this, and a voltage that indicates the state of distortion (displacement) of the piezoelectric element due to the positive piezoelectric effect. Informational use of signals, for example, underwater communication devices (sonar), fish detectors (deepening devices), distance meters, nondestructive inspection devices (ultrasonic flaw detectors), ultrasonic diagnostic devices, ultrasonic thickness meters, flow meters Piezoelectric elements can also be used for such as.

Although the best configuration, method and the like for carrying out the present invention have been disclosed in the above description, 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 can be made by those skilled in the art in terms of materials, quantity, and other detailed configurations.
Therefore, the description limited to 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 remove | excluded the limitation of one part or all of such restrictions is included in this invention.

1 is an external plan view of a timepiece according to a first embodiment of the present invention. The top view of the date display apparatus with which the said timepiece is equipped. The perspective view of the piezoelectric actuator with which the said piezoelectric actuator unit is provided. IV-IV sectional view taken on the line of FIG. VV sectional view taken on the line of FIG. The figure which shows the manufacturing process of the reinforcement board with which the said piezoelectric actuator is provided. The disassembled perspective view which shows the joint surface of the piezoelectric element with which the said piezoelectric actuator is provided, and the joint surface of a reinforcement board. The figure which shows the electrical connection of the said piezoelectric actuator. The figure which shows operation | movement of the said piezoelectric actuator. The figure which has arrange | positioned the solder to a piezoelectric element in the manufacturing process of the said piezoelectric actuator. The disassembled perspective view which shows the aspect on which the piezoelectric element in which solder is arrange | positioned, and a reinforcement board are laminated | stacked. The figure which shows the joining process which joins a piezoelectric element and a reinforcement board with the pressurization apparatus and heating apparatus as a manufacturing apparatus of the said piezoelectric actuator. The disassembled perspective view which shows the piezoelectric actuator of 2nd Embodiment. The disassembled perspective view which shows the aspect on which the piezoelectric element in which solder is arrange | positioned, and a reinforcement board are laminated | stacked. The disassembled perspective view which shows the piezoelectric actuator of 3rd Embodiment. The disassembled perspective view which shows the aspect on which the piezoelectric element in which solder is arrange | positioned, and a reinforcement board are laminated | stacked. The figure which shows the 1st modification of 3rd Embodiment. The figure which shows the 2nd modification of 3rd Embodiment. The disassembled perspective view which shows the piezoelectric actuator of 4th Embodiment. The figure which shows the pressurization apparatus and heating plate as a manufacturing apparatus of the said piezoelectric actuator. The top view which shows the lower board of the said pressurization apparatus. The figure which shows the piezoelectric actuator of 5th Embodiment. The figure which shows the piezoelectric actuator of 6th Embodiment. The figure which shows the piezoelectric actuator of 7th Embodiment. The figure which shows the piezoelectric actuator of 8th Embodiment. The figure which shows the piezoelectric actuator of 9th Embodiment. Schematic of a printer in a tenth embodiment. FIG. 3 is a perspective view of a piezoelectric actuator unit incorporated in the printer. The figure which shows the piezoelectric actuator which concerns on this invention. The figure which shows the pressurization jig | tool as a manufacturing apparatus of the piezoelectric vibrating body of this invention. FIG. 6 is an exploded perspective view showing a bonding surface of a reinforcing plate from which an oxide film has been removed and a bonding surface of a piezoelectric element, which is a modification of the present invention. The figure which shows the state by which the piezoelectric element and the reinforcement board were joined with the solder. The figure which shows the prior art example with which the piezoelectric element and the reinforcement board were joined by the adhesive agent.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Electronic timepiece (electronic device), 7 ... Printer (electronic device), 20 ... Piezoelectric actuator, 20A ... Piezoelectric vibrator, 21 ... Piezoelectric element, 21B ... Joining surface, 21L: outer edge portion, 22: reinforcing plate, 22L: side surface (side surface of reinforcing member), 22B: joining surface (joining surface of reinforcing member), 28: rotor (driven body) 30 ... piezoelectric actuator, 30 ... solder layer, 31 ... solder, 31F ... flux, 31A ... alloy layer, 32 ... reinforcing plate, 33 ... coating (solder), 40 ... piezoelectric actuator, 45 ... piezoelectric actuator, 50 ... piezoelectric actuator, 51 ... piezoelectric element, 51B ... joining surface, 52 ... reinforcing plate, 52B ... joining surface, 53 ... Piezoelectric actuator, 55 ... Piezoelectric 56 ... Piezoelectric element, 56A ... Inclined surface, 56B ... Joining surface, 57 ... Piezoelectric actuator, 58 ... Piezoelectric element, 58B ... Joining surface, 58A ... Step part 59 ... piezoelectric actuator, 60 ... piezoelectric actuator, 62 ... reinforcing plate, 91 ... piezoelectric element, 92 ... reinforcing plate, 110 ... pressure device, 111A ... 111B ... groove (non-contact part), 111C ... positioning pin (jig), 111D ... hanging part, 120 ... heating device, 130 ... pressure jig, 135 ... Positioning pins (jigs), 139 ... heating members, 141 ... movement (timer), 142 ... dial (time information display), 143 ... hour hand (time information display), 144 ... minute hand (time information display part), 145 ··· Second hand (time information display part), 210 ··· Electrode (metal coating), 220 ··· Electrode (metal coating), 220Z · · · insulating member, 221 · · · reinforcing plate body, 222A, 222B ..Protrusions (contact portions), 223... Support portion, 320Z... Bonding material non-adhesion portion, 320... Electrode (metal coating), 320X ... non-coating portion, 321A, 321A.・ Near position, 321B, 321B ... Near position, 321 ... Reinforcement plate body, 322A, 322B ... Protrusion part (contact part), 323 ... Support part, 410X ... Non-coating part, 410 ... Electrode (metal coating), 410X ... Non-coating part, 420 ... Electrode (metal coating), 420X ... Non-coating part, 452 ... Electrode (metal coating), 452X ... Non-coating part, 453 ... Solder foil, 521 ... Reinforcement board Body, 591 ... Gap material, 620X ... Non-coating part, 621 ... Reinforcing plate main body, 622A, 622B ... Projection part (contact part), 623 ... Support part.

Claims (17)

A piezoelectric element, and a reinforcing member joined to the piezoelectric element,
The joint portion of the piezoelectric element with the reinforcing member is configured to have a metal film,
The joint portion of the reinforcing member with the piezoelectric element is configured to have a metal film, or the oxide film of the joint portion is removed,
The piezoelectric vibration member, wherein the piezoelectric element and the reinforcing member are bonded to each other at a bonding portion with a metal bonding material. The piezoelectric vibrating body according to claim 1,
The piezoelectric vibration member, wherein the metal bonding material is solder. The piezoelectric vibrating body according to claim 1,
The reinforcing member is plate-shaped,
On the plane of the reinforcing member, a metal coating is formed, at least a part of which constitutes the joint,
No metal coating is formed on the side surface of the reinforcing member,
The piezoelectric vibrating body, wherein the wettability of the metal coating on the plane of the reinforcing member with the metal bonding material is better than the wettability of the side surface with the metal bonding material. The piezoelectric vibrating body according to claim 1,
The reinforcing member has a reinforcing member body having a joint with the piezoelectric element, and a portion other than the reinforcing member body,
At least in the vicinity of the joint portion of the reinforcement member main body in a portion other than the reinforcement member main body, the wettability with the metal joint material is greater than the wettability with the metal joint material at the joint portion of the reinforcement member main body. A piezoelectric vibration member characterized in that a bonding material non-adhered portion which is inferior is formed. The piezoelectric vibrating body according to claim 4,
Only the reinforcing member main body in the reinforcing member is formed with a metal film that constitutes the joint portion,
The bonding material non-adhering portion is a non-coating portion where a metal coating is not formed on the reinforcing member. The piezoelectric vibrating body according to claim 4,
A metal film, at least a part of which constitutes the joint, is continuously formed on the reinforcing member body and a portion other than the reinforcing member body,
The bonding material non-adhering portion is provided on a surface of the metal film. The piezoelectric vibrating body according to claim 4 or 6,
The bonding material non-adhering portion is formed of an insulating member. The piezoelectric vibrating body according to claim 1,
The reinforcing member has a reinforcing member main body having a joint with the piezoelectric element, and a portion other than the reinforcing member main body,
The reinforcing member main body is formed with a metal coating that constitutes the joint portion,
A position near a portion other than the reinforcing member main body in at least one of the piezoelectric element and the reinforcing member main body is a non-coating portion where a metal coating is not formed. In the piezoelectric vibrating body according to any one of claims 4 to 8,
The part other than the reinforcing member main body is a support portion that is connected to the reinforcing member main body and supports the piezoelectric element. In the piezoelectric vibrating body according to any one of claims 4 to 9,
A piezoelectric actuator that drives the driven body by transmitting the vibration of the piezoelectric vibrating body;
A portion other than the reinforcing member main body is a contact portion that is connected to the reinforcing member main body and is in contact with the driven body. The piezoelectric vibrating body according to claim 1,
The piezoelectric element and the reinforcing member are laminated and bonded to each other,
At the time of joining, a jig that extends along the laminating direction and contacts the outer peripheral portion of the piezoelectric element and the outer peripheral portion of the reinforcing member is used,
The reinforcing member is formed with a metal film that constitutes the joint portion,
A piezoelectric vibrating body, wherein a position in the vicinity of the jig in at least one of the piezoelectric element and the reinforcing member is a non-coating portion where a metal coating is not formed. The piezoelectric vibrating body according to claim 1,
The piezoelectric element and the reinforcing member are laminated and bonded to each other,
The bonding surface of the piezoelectric element with the reinforcing member and the bonding surface of the reinforcing member with the piezoelectric element have different sizes.
One of the joining surface of the piezoelectric element and the joining surface of the reinforcing member extends to the outside of the other. The piezoelectric vibrator. The piezoelectric vibrating body according to claim 12,
The piezoelectric element and the reinforcing member are each formed as a plate-like member having different plane dimensions,
The piezoelectric vibrator and the reinforcing member are laminated and joined in a thickness direction. A piezoelectric vibrating body according to any one of claims 1 to 13,
An electronic apparatus comprising: a driven body driven by vibration of the piezoelectric vibrating body. The electronic device according to claim 14 is:
A timepiece that measures time and a time information display unit that displays time information by the time unit, and the driven body is a driving body that drives the time information display unit. Electronic equipment. A bonding step of bonding a piezoelectric element having a metal film and a reinforcing member for reinforcing the piezoelectric element;
The joint of the piezoelectric element with the reinforcing member is configured with a metal coating, and the joint of the reinforcing member with the piezoelectric element is configured with a metal coating or oxidation of the joint. In a state where the film is removed, in the joining step, the piezoelectric element and the reinforcing member are joined with a metal joining material. The method for manufacturing a piezoelectric vibrating body according to claim 16,
In the bonding step, a metal bonding material is supplied to either the bonding portion in the reinforcing member or the bonding portion in the piezoelectric element by any one of screen printing, solder plating, and arrangement of solder foil, A method of manufacturing a piezoelectric vibrating body, characterized in that no metal bonding material is supplied to any other part.

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