JP2008092450A - Piezoelectric element - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a piezoelectric element of a small outer shape dimension for which a wiring process and a soldering process are facilitated even while providing required resistance against the stress of an amplitude or the like, that is to reduce disconnections and solder peeling, etc., to improve the yield of a manufacture process and to improve the quality and reliability of a product. <P>SOLUTION: The piezoelectric element comprises a plurality of substrates 2a and 2b arranged side by side at a fixed interval, ceramic plates 3a and 3b stuck to the respective substrates 2a and 2b, and a wiring material 9 composed of a tinselled wire or a strand for electrically connecting the respective substrates 2a and 2b. Wiring holes 6a and 6b for respectively inserting the wiring material 9 are formed on the respective substrates 2a and 2b, and the respective substrates 2a and 2b are connected through the wiring material 9 inserted to the respective wiring holes 6a and 6b. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a piezoelectric element.

In recent years, panel type speakers using a protection panel of a display device as a diaphragm have been developed. The panel type speaker is configured to excite vibrations in the protective panel by fixing the vibration element to a protective panel used as a diaphragm and transmitting vibration from the vibration element to the protective panel. Since such panel type speakers are small and have high sound quality, they are widely used in small terminal devices such as portable small telephones (see, for example, Patent Document 1).
By the way, conventionally, in order to enjoy music in situations where helmets such as motorcycles are mandatory, there are methods such as wearing normal earphones and headphones, or installing speakers on motorcycle vehicles. Has been done. However, when wearing normal earphones or headphones, the earphones worn on the ears may be caught when the helmet is attached or removed, which may be inconvenient. In addition, when a speaker is installed in a motorcycle vehicle, the volume may leak to the outside if the volume is set to be appropriate for the passenger when wearing a helmet, and the volume may be loud when stopped and cause noise damage to the surroundings. There was sex.
In order to solve such problems, a vibrator for mounting on a cowl or the like of a motorcycle is known.

As a vibration element in such a vibrator, as shown in FIG. 8, for example, two substrates 31a and 31b are arranged vertically in parallel, and the two substrates 31a and 31b are electrically connected to each other. A piezoelectric element 30 having a structure is known.
In such a structure, the protrusions 32a and 32b are provided on the substrates 31a and 31b, and the wiring member 33 such as an electric wire is wound around the protrusions and soldered.
Further, when there is no protrusion on the substrate, the wiring material is soldered by spotting on the side surface of the substrate.
JP 2005-66500 A

However, since the piezoelectric element is provided with a protrusion on the substrate, the size of the piezoelectric element is increased. Accordingly, the vibrator for mounting the piezoelectric element is also increased in size.
In addition, when a large signal is input or the operation is continuously performed, the wiring material cannot withstand a large amplitude and has a problem such as disconnection or solder peeling.
Also, when soldering is performed by spotting the wiring material on the side surface of the board without providing a protrusion on the board, the resistance of the soldered part is weak against stresses such as amplitude because of the spotting, There is a problem that solder peeling is likely to occur.

  The present invention has been made in view of the above points, and provides a piezoelectric element that has a required resistance to stresses such as amplitude and that is easy to wire and solder and has a small outer dimension. It is the purpose. Furthermore, it aims at improving the quality and reliability of a product while improving the yield of a manufacturing process by reducing generation | occurrence | production of a disconnection, solder peeling, etc.

In order to achieve the object, the invention described in claim 1
A plurality of substrates arranged side by side at regular intervals;
A ceramic plate attached to each of the substrates;
A wiring material composed of a tinsel wire or a stranded wire for electrically connecting the substrates;
Each substrate is formed with a wiring hole for inserting the wiring material,
Each of the substrates is connected via the wiring material inserted into each of the wiring holes.

  According to a second aspect of the present invention, in the piezoelectric element according to the first aspect, each of the wiring holes is provided at a position where the central axis is coaxial.

  According to a third aspect of the present invention, in the piezoelectric element according to the first aspect, the wiring holes are provided at positions having different central axes.

  According to a fourth aspect of the present invention, in the piezoelectric element according to any one of the first to third aspects, the ceramic plates are cut away from the wiring holes around the wiring holes. It is characterized by providing.

  According to a fifth aspect of the present invention, in the piezoelectric element according to the fourth aspect, each of the substrates includes an insulating portion in an inner portion of the notch of the ceramic plate.

According to the present invention, since wiring is performed by inserting a wiring material into the wiring hole, there is no need to provide a protrusion on the substrate, and the piezoelectric element can be miniaturized.
Further, since wiring is performed by inserting a wiring material into the wiring hole, there is no need to wrap the wiring material, and the wiring process and the soldering process can be facilitated.

  In addition, by improving the resistance to stress of the wiring material, the occurrence of insulation and solder peeling is reduced, so the durability of the piezoelectric element is improved, the reliability of the product can be improved, and the yield of the manufacturing process is increased. Can be good.

Hereinafter, an embodiment according to the present invention will be described with reference to FIGS. 1 and 2. However, the scope of the invention is not limited to the illustrated examples.
FIG. 1 is a perspective view showing a piezoelectric element 1 according to the present invention, and FIG. 2 is an enlarged view of a main part of the piezoelectric element 1 shown in FIG.

As shown in FIG. 1, the piezoelectric element 1 has two substrates 2 a and 2 b made of rectangular metal plates arranged at a certain interval and vertically in parallel.
On each of the substrates 2a and 2b, rectangular ceramic plates 3a and 3b that are slightly smaller than the substrates 2a and 2b are respectively mounted.

  A gap holding member 4 is disposed in the gap at one end of the substrates 2a and 2b. The upper holding member 5a is provided on the surface of the gap holding member 4 that faces through the substrate 2a (the upper surface of the substrate 2a), and the surface of the gap holding member 4 that faces through the substrate 2b (the lower surface of the substrate 2b). Is provided with a lower holding member 5b. The upper and lower sandwiching members 5a and 5b, the gap holding member 4, and the substrates 2a and 2b are fixed by two screws passing through them, and the substrate 2a and the substrate 2b are cantilever beams having a constant interval. It is supported in the shape.

As shown in FIG. 2, wiring holes 6a and 6b that pass through the substrates 2a and 2b and have a coaxial central axis are formed on one side in the vicinity of the base ends of the substrates 2a and 2b, respectively. The ceramic plates 3a and 3b are formed with semicircular cutouts 7a and 7b that retreat from the wiring holes 6a and 6b around the wiring holes 6a and 6b, respectively. The inside of 7a, 7b is a solder area. A wiring material 9 is inserted linearly into the wiring holes 6a and 6b. The protruding portions of the wiring member 9 from the substrates 2a and 2b are fixed by solder in the solder regions inside the notches 7a and 7b of the substrates 2a and 2b. For this reason, the board | substrate 2a and the board | substrate 2b are electrically connected, without the soldering part and ceramic board 3a, 3b contacting.
Insulating portions for reliably preventing contact between the soldered portions and the ceramic plates 3a and 3b may be provided on the inner portions of the notches 7a and 7b of the substrates 2a and 2b.

  Moreover, the wiring material 9 used here is a tinsel wire or a stranded wire formed by knitting a plurality of so-called single wires in which a heat resistant fiber such as Kevlar is used as a core material and a copper foil is wound around the core material.

  The piezoelectric element 1 is connected to a communication cable (not shown), and for example, a music signal or a voice signal transmitted from a portable music device or the like is input via the communication cable.

Next, an example in which the piezoelectric element 1 is applied to the vibrator 10 will be described.
FIG. 3 is a perspective view of the vibration exciter 10 to which the piezoelectric element 1 of FIG. 1 is attached, and FIG. 4 is a bottom view of the vibration exciter 10. FIG. 5 is a transparent perspective view of the vibrator 10 of FIG.
As shown in FIG. 3 to FIG. 5, the vibrator 10 includes a piezoelectric element 1, a dome-shaped case 11 for housing the piezoelectric element 1, and a case 11 such as a cowl of a motorcycle or a full-face helmet. And a spring-like clip 12 provided so as to be detachable from an installation surface having a curved surface shape such as a shield.

  The case 11 has a bottom plate 13 that is concave so as to follow the curved shape of the installation surface. A lower holding member 5b, which is the lower surface of the piezoelectric element 1, is fixed to the approximate center of the upper surface of the bottom plate 13. In addition, on the lower surface of the bottom surface 13, a sticking surface for bringing the bottom plate 13 into close contact with the installation surface is provided. At the top of the bottom plate 13, a cap 14 is provided in which the piezoelectric element 1 is accommodated in the opening and the lower surface opening is closed by the bottom plate 13, and the piezoelectric element 1 is accommodated in the case 11. The case 11 is formed of, for example, resin or metal, but may have a required hardness and light weight, and the material thereof is not limited.

The case 11 is provided with a clip 12 integrally formed by bending a bar-shaped member such as an elastically deformable metal or resin symmetrically.
One end of the pair of left and right base portions 15, 15 of the clip 12 is inserted into the cap 14 from the surface side of the cap 14 and is fixed inside the cap 14. The other ends of the base portions 15 and 15 are bent and extended downward in an L shape, and are connected to one ends of the holding portions 16 and 16. The sandwiching portions 16, 16 extend below the bottom plate 13 along the bottom plate 13, and the other ends of the sandwiching portions 16, 16 are connected to both ends of the pressing portion 17, respectively. With such a shape, an installation surface can be inserted between the pressing portion 17 and the bottom plate 13. The vibrator 10 is fixed on the installation surface by sandwiching the installation surface between the holding portions 16 and 16 and the bottom plate 13 and pressing the installation surface with the pressing unit 17.

  Next, the operation of this embodiment will be described.

First, the vibration exciter 10 is detachably installed on the installation surface by sandwiching the installation surface with the clip 12. Since the bottom surface 13 of the vibration exciter 10 is a concave surface along the installation surface, it closely contacts the installation surface having a curved surface.
The piezoelectric element 1 accommodated in the vibrator 10 is vibrated via a communication cable that applies a voltage in accordance with an input music signal, audio signal, or the like. Since the lower holding member 5b, which is the lower surface of the piezoelectric element 1, is fixed to the upper surface of the bottom plate 13 of the vibrator 10, the vibration of the piezoelectric element 1 is transmitted to the installation surface via the bottom plate 13 to reproduce music. Is done.

In such a piezoelectric element 1, since the wiring holes 6a and 6b for inserting the wiring material 9 are formed in the substrates 2a and 2b, it is not necessary to separately provide protrusions for electrical connection on the substrates 2a and 2b. At the same time, it is not necessary to wind and connect the wiring material 9.
In addition, since an electric material that is strong against bending, such as a tinted wire or a stranded wire, is used as the wiring material 9, even if a large signal is generated or a large amplitude occurs due to continuous operation, the wiring material 9 It is possible to reduce deterioration of cracks and the like, and to reduce solder peeling due to stress applied to the soldered portion.

Further, since the notches 7a and 7b for retracting the ceramic plates 3a and 3b from the wiring holes 6a and 6b are formed around the wiring holes 6a and 6b, the wiring material 9 protruding from the wiring holes 6a and 6b is formed. Is soldered to the substrates 2a and 2b, contact between the soldered portion and the ceramic plates 3a and 3b can be prevented to avoid conduction.
In addition, when an insulating part is provided in the inner part of the notches 7a and 7b of the substrates 2a and 2b, contact between the soldered part and the ceramic plates 3a and 3b can be surely prevented to avoid conduction.

As described above, according to the piezoelectric element configured as in the present embodiment, it is not necessary to provide a protrusion on the substrate, so that the piezoelectric element can be reduced in size. For this reason, it can be stored in a narrow storage place, and the vibration exciter that accommodates the piezoelectric element can be downsized.
In addition, since it is not necessary to wrap a wiring material for connecting the substrates, wiring work and soldering work can be facilitated in the manufacturing process of the piezoelectric element.
Further, since the deterioration of the wiring material and the soldering portion is reduced, the yield is improved, and thus the reliability of the product itself can be improved.

In the present embodiment, the central axes of the wiring holes 6a and 6b formed in the substrates 2a and 2b are coaxial, but the wiring holes 6a and 6b are located at different positions as shown in FIG. Can also be formed.
Thus, when the central axes of the wiring holes 6a and 6b of the upper and lower substrates 2a and 2b are formed at different positions, the wiring material 9 made of tinsel wire or the like is formed in a crank shape between the substrate 2a and the substrate 2b. It is bent and inserted into the wiring hole 6a and the wiring hole 6b.
By doing in this way, the wiring material 9 can be made into a structure strong against bending.

In the present embodiment, the piezoelectric element having the two substrates 2a and 2b has been described. However, as shown in FIG. 7, a third substrate 2c may be provided. At this time, in order to dispose the substrate 2c between the upper sandwiching member 5a and the lower sandwiching member 5b, it is fundamental except that the second gap holding member 4 is provided between the substrate 2b and the substrate 2c. The structure is the same.
As described above, according to this embodiment, two or more substrates are applicable, and the number is not limited.

  In addition, it is needless to say that the present invention is not limited to the above embodiment and can be modified as appropriate.

1 is a perspective view of a piezoelectric element according to the present invention. It is a perspective view which shows the principal part structure of the piezoelectric element in FIG. It is a perspective view of the vibrator using the piezoelectric element in FIG. It is a bottom view of the vibrator in FIG. FIG. 4 is a transparent perspective view of the vibrator in FIG. 3. It is a modification of the piezoelectric element which concerns on this invention. It is a modification of the piezoelectric element which concerns on this invention. It is a perspective view of the conventional piezoelectric element.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Piezoelectric element 2a, 2b, 2c Board | substrate 3a, 3b Ceramic board 4 Gap holding member 5a Upper clamping member 5b Lower clamping member 6a, 6b Wiring hole 7a, 7b Notch 9 Wiring material 10 Exciter 11 Case 12 Clip 13 Bottom plate 14 Cap 15 Base portion 16 Holding portion 17 Holding portion

Claims (5)

A plurality of substrates arranged side by side at regular intervals;
A ceramic plate attached to each of the substrates;
A wiring material composed of a tinsel wire or a stranded wire for electrically connecting the substrates;
Each substrate is formed with a wiring hole for inserting the wiring material,
Each of the substrates is connected via the wiring material inserted into each of the wiring holes.   The piezoelectric element according to claim 1, wherein each wiring hole is provided at a position where a central axis thereof is coaxial.   The piezoelectric element according to claim 1, wherein the wiring holes are provided at positions where central axes thereof are different from each other.   4. The piezoelectric element according to claim 1, wherein each ceramic plate includes a notch that retreats from the wiring hole around each wiring hole. 5.   5. The piezoelectric element according to claim 4, wherein each of the substrates includes an insulating portion in an inner portion of a notch of the ceramic plate.

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