JP2002141573A - Mounting structure of piezoelectric transformer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a mounting structure for a piezoelectric transformer capable of handling a large electric power of the piezoelectric transformer while standing against external impact. SOLUTION: The mounting structure of a piezoelectric transformer, housed in a case, is provided in which, with a piezoelectric body provided with a primary-side electrode and a secondary-side electrode, the primary-side electrode is applied with an AC voltage so that the piezoelectric body is excited with a mechanical vibration to output a voltage from the secondary-side electrode, with each electrode allowed to be extracted outside. The electrodes are provided to the side surfaces of the piezoelectric body while its case comprises aligned protruding parts corresponding to one of the electrodes on its inside wall surface. At least the inside wall surface of a case comprising the protruding parts is coated with an insulating elastic body, with a conductor piece fitted to the inside surface that forms the protruding part. With the piezoelectric transformer housed in the case, the electrodes contact the conductor pieces on the cased side, to be extracted outside through the conductor pieces.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a piezoelectric transformer used as, for example, a step-up / step-down circuit element, and more particularly to a mounting structure thereof.

[0002]

2. Description of the Related Art Piezoelectric transformers which have been conventionally developed as step-up transformers for high-voltage power supplies have not been commercialized due to material restrictions such as breaking strength of piezoelectric ceramic materials. In recent years, as the development of high-strength piezoelectric ceramic materials has progressed and the demand for miniaturization and thinning of portable information devices (for example, notebook personal computers and portable terminals) has increased, the liquid crystal backing mounted on these devices has been increasing. It is drawing attention again as a step-up transformer for power supply of a light inverter.

[0003] A piezoelectric transformer basically includes a primary electrode (input side electrode) and a secondary side electrode (output side electrode) formed on a piezoelectric ceramic material such as lead zirconate titanate (PZT) or a piezoelectric crystal material such as lithium niobate. Side electrode) is formed, and in such a configuration, the piezoelectric transformer is mechanically vibrated as an AC voltage near the resonance frequency of the piezoelectric transformer is applied to the primary side electrode, This mechanical vibration is converted by the piezoelectric effect, and a high voltage can be output from the secondary electrode. Piezoelectric transformers can be smaller and thinner than conventionally known electromagnetic transformers, and can achieve high conversion efficiency.

Next, an example of a conventionally known piezoelectric transformer will be described. FIG. 11 is a perspective view of a conventional piezoelectric transformer. In this piezoelectric transformer 100, primary electrodes (input electrodes) 111 and 112 are formed at corresponding positions on the front surface and the rear surface at one end side of the flat piezoelectric member 110, respectively. At the other end, a secondary electrode (output electrode) 113 is formed on a part of the surface side. The arrow in FIG. 11 indicates the direction in which the piezoelectric body 110 is polarized in advance, and the piezoelectric body 110 is moved by the primary electrodes 111 and 112 in the thickness direction (arrow a).
And the input electrodes 111 and 112 and the output electrode 113 are polarized in the longitudinal direction (arrow b).

[0005] In the piezoelectric transformer 100 having such a configuration, when an AC voltage near the resonance frequency of the piezoelectric transformer 100 is applied to the primary electrodes 111 and 112, the piezoelectric transformer 100 is driven by the inverse piezoelectric effect. A mechanical vibration that expands and contracts in the length direction (arrow b) is excited, and this mechanical vibration is converted into a high voltage by the piezoelectric effect and output from the secondary electrode 113. At this time, the amplitude of the amplitude is maximum near both end faces in the length direction of the piezoelectric body 110, and has a node near the center, and excites a half-wavelength mechanical vibration along the length direction. Transformers, generally, λ
It is referred to as a piezoelectric transformer of a / 2 vibration mode (λ represents one wavelength).

[0006] In general, the piezoelectric transformer body is packaged and mounted for mechanical protection from the outside and easy handling. As a mounting structure of the piezoelectric transformer, a structure using conductive rubber is well known. FIGS. 12A and 12B are a longitudinal sectional view and a transverse sectional view taken along line AA in FIG. 12A, respectively, showing a mounting structure of the piezoelectric transformer 100 using conductive rubber. is there. Here, the piezoelectric transformer 100
Are driven in the λ / 2 mode, and the input electrodes 111 and 112 correspond to nodes of vibration.

In this structure, the piezoelectric transformer 100 is housed in a case composed of a pair of insulating half members 121a and 121b, and inside the case, two pairs of conductive rubbers 122a and 122b, 123a and 123b are formed. ,
The piezoelectric transformer 100 is supported by being urged from above and below. In a state where the piezoelectric transformer 100 is supported, the conductive rubbers 122a and 122b are electrically connected to the input electrodes 111 and 112 (not shown in FIG. 12), respectively. This is performed via metal electrode extraction members 124a and 124b provided outside the conductive rubbers 122a and 122b. Similarly, the conductive rubber 123a is electrically connected to the output electrode 113, and extraction of the electrode from the output electrode 113 to the outside is performed via a metal electrode extraction member 125a disposed outside the conductive rubber 123a. Done.

[0008]

However, in the mounting structure using such a conductive rubber, it is difficult to handle the large power of the piezoelectric transformer from the following points. That is, in the mounting structure using the conductive rubber, the piezoelectric transformer 100 is fixed by the conductive rubber inside the case.
Although having sufficient resistance to external impact, the resistance component of the conductive rubber cannot be ignored with the increase in the voltage applied to the piezoelectric transformer 100, and as a result, the vibration of the piezoelectric transformer 100 may be hindered. There is. Further, since it is necessary to urge the conductive rubber against the piezoelectric transformer, there is a problem that in order to perform this, the entire mounting structure including the case becomes large.

As a structure different from the mounting structure using conductive rubber, for example, a mounting structure in which electrodes are taken out using an elastic metal material as disclosed in Japanese Patent Application Laid-Open No. H11-121827, JP-A-11-354856
There has been proposed a mounting structure for taking out an electrode by using a flexible member as disclosed in Japanese Patent Application Laid-Open No. H10-260,036.

The present invention has been made in view of the above technical problem, and provides a mounting structure of a piezoelectric transformer capable of handling a large amount of power of the piezoelectric transformer while having sufficient resistance to an external impact. The purpose is to:

[0011]

According to the first aspect of the present invention, a primary electrode and a secondary electrode are formed on a piezoelectric body,
An AC voltage is applied to the primary side electrode, and a piezoelectric transformer that outputs a voltage from the secondary side electrode by exciting mechanical vibrations to the piezoelectric body makes it possible to take out each electrode to the outside. In the mounting structure of the piezoelectric transformer housed therein, the piezoelectric transformer has the primary electrode and the secondary electrode on the side surface of a piezoelectric body, while the case has the primary electrode and the inner electrode on the inner wall surface side. An inner surface having protrusions positioned corresponding to one of the secondary electrodes, and having at least an inner wall surface of a case including the protrusions coated with an insulating elastic material; Each of the electrodes has a conductor piece attached to the piezoelectric transformer, and in a state where the piezoelectric transformer is housed in a case,
It is characterized in that it comes into contact with the conductor piece on the case side and is taken out through the conductor piece.

According to the invention of claim 2 of the present application, a primary electrode and a secondary electrode are formed on a piezoelectric body, an AC voltage is applied to the primary electrode, and mechanical vibration is excited on the piezoelectric body. In the mounting structure of the piezoelectric transformer housed in the case, the piezoelectric transformer that outputs a voltage from the secondary-side electrode allows the electrodes to be taken out of the case. At least one of the surfaces constituting
One has the primary side electrode and the secondary side electrode, while the case has an opening positioned corresponding to one of the primary side electrode and the secondary side electrode, and the inner wall surface of the case has Coated with an insulating elastic material, with the piezoelectric transformer stored in the case,
Each of the electrodes is exposed from the opening and taken out.

Further, the invention according to claim 3 of the present application is characterized in that, in the invention according to claim 2, each electrode exposed from the opening is taken out through a conductive flexible member. is there.

Further, according to a fourth aspect of the present invention, in any one of the first to third aspects of the present invention, the side surface of the case is arranged so that the piezoelectric transformer is housed in the case. The piezoelectric transformer comprises a flat portion facing the side surface along the longitudinal direction of the piezoelectric transformer and a curved surface portion facing the side surface along the width direction.

[0015]

Embodiments of the present invention will be described below with reference to the accompanying drawings. Embodiment 1 FIG. FIG. 1 is a perspective view showing a mounting structure of a piezoelectric transformer according to Embodiment 1 of the present invention. Hereinafter, a case where the piezoelectric transformer is driven at λ / 2 will be described as an example. In this mounting structure, the piezoelectric transformer 1 in which the input electrodes 2 and 3 and the output electrode 4 are provided at predetermined positions of the flat piezoelectric member 5 is housed and fixed in the insulating case 10. The piezoelectric transformer 1 is provided at a pair of primary electrodes (hereinafter, referred to as input electrodes) 12 and 13 formed at substantially the center of both outer wall surfaces extending along the longitudinal direction of the main body, and at one end of the outer wall surfaces. Electrodes 4a, 4c and the electrodes 4
and a secondary electrode (hereinafter referred to as an output electrode) 4 composed of an electrode 4b provided at one end of the surface of the piezoelectric body 5 so as to be continuous with the electrodes a and 4c.

On the other hand, the case 10 has a pair of protrusions 11, 12 provided at substantially the center of both inner wall surfaces extending along the longitudinal direction of the main body, and both inner wall surfaces extending along the longitudinal direction of the main body. A pair of protrusions 13 and 14 provided on one end side of the
And Further, the inner wall surface of the case 10 including the wall surfaces forming the protrusions 11 is coated with an insulating elastic body 15 made of a material such as silicon rubber.

Each of the electrodes 2, 3, 4 on the piezoelectric transformer 1 side
And the respective projecting portions 16, 17, 18, 1 on the case 10 side.
9 are positioned so that they correspond to each other. That is, the input electrodes 2 on the piezoelectric transformer 1 side,
3 are arranged at positions that can correspond to the protruding portions 11 and 12 on the case 10 side, respectively, and the output electrodes 4a and 4c on the piezoelectric transformer 1 side correspond to the protruding portions 13 and 14 on the case 10 side, respectively. It is located in a position where it can be done.

With reference to FIG. 2, a description will be given of a manufacturing process of the mounting structure of the piezoelectric transformer 1. FIG.
(D) shows the steps for mounting the piezoelectric transformer 1 on the molded insulating case 10 sequentially. As can be seen from FIG. 2A, projecting portions 11 facing each other are provided on both inner wall surfaces along the longitudinal direction of the case 10.
And 12, 13, and 14 are formed. In the vicinity of the inside of each of the projections 11, 12, 13, and 14, slit holes 25, 25 are formed along the width direction of each projection.
26, 27 and 28 are formed.

Next, as can be seen from FIG. 2 (b), the inner wall surface of the case 10 is coded with an insulating elastic body 15 after masking the peripheral portion of the inner wall surface of the case 10. Note that, in FIG. 2B, a portion where the elastic body 15 is coated is indicated by oblique lines and bold lines.

Subsequently, as shown in FIG. 2 (c), elongated conductor pieces 21, 22, 2 serving as electrode extraction members to the outside are provided in slit holes 25, 26, 27, 28, respectively.
3 and 24 are inserted. As a material of these conductor pieces, for example, an elastic material such as a phosphor bronze material is used. Then, the portion of each conductor piece protruding toward the back side of the case is bent outward.

Thereafter, a conductive adhesive is applied to the inner surfaces of the one end portions 21a, 22a, 23a and 24a of the conductor pieces protruding toward the case surface side, and as shown in FIG.
Input electrodes 2 and 3 and output electrodes 4a and 4 of piezoelectric transformer 1
c is one end 21a, 22a, 2 of each conductor piece, respectively.
3a and 24a, the piezoelectric transformer 1
Is pressed into the case 10 to cure the conductive adhesive between the electrodes and the conductor pieces. With the above, Case 1
0 is completed.

In the mounting structure manufactured in such a process, the piezoelectric transformer 1 is connected to the conductive pieces 21, 22, 23, 24 having a lower resistance component than the conductive rubber used in the prior art and the conductive adhesive. Since the electrodes are taken out, it is possible to handle the piezoelectric transformer 1 stably with high power. In addition, since the piezoelectric transformer 1 is surrounded by the insulating elastic body 15 in the case 10, sufficient resistance to external impact can be ensured. For example, the electrodes 2 of the piezoelectric transformer 1 bonded by a conductive adhesive
Although the adhesive force between the conductor pieces 3, 4a, 4c and the conductor pieces 21, 22, 23, 24 is relatively weak, the adhesion between the conductor pieces, due to the insulating elastic body that comes into contact with the outer surface side of each conductor piece, is made external. Fully protected from impact from In this mounting structure, the piezoelectric transformer 1 includes relatively thin conductor pieces 21, 22, 23, 2.
Since it is mounted in the case 10 only through the elastic member 4 and the insulating elastic body 15, its structure is relatively small.

In order to further improve the resistance to external shocks, as shown in FIG.
After being bent along the outer wall surface of the piezoelectric transformer 1, a cover panel 29 made of an elastic material may be provided to cover the surface side of the piezoelectric transformer 1 arranged in the case 10. The cover panel 29 is adhered to the case body by an adhesive applied to the upper end of the case 10. In this case,
The piezoelectric transformer 1 is confined in the case 10, but is generated by continuous driving of the piezoelectric transformer 1 by forming a hole in a part of the case 10 for communicating the inner wall surface side and the outer wall surface side of the case 10. The heat may be radiated to the outside.

Further, in order to take out the electrodes of the piezoelectric transformer 1 to the outside, a structure as shown in FIG. 4 may be used. FIG.
(A) and (b) are a plan view and a side view of the mounting structure after the piezoelectric transformer 1 is disposed in the case, respectively. In this structure, the case 30 is provided with slit holes 25 and 2 for inserting conductor pieces as shown in FIG.
6, 27, 28, instead of the inner wall surface and the outer wall surface of the case 30 at the portion where the protrusions 11, 12, 13, 14 on the inner wall surface of the case 30 are provided. Communicating holes 35, 36, 3 formed so as to communicate with each other.
7,38. After the inner wall surface of the case 30 is coated with the insulating elastic body 15, the protrusions 11, 1 are formed.
The conductor pieces 31, 32, 33, 34 are attached to 2, 13, and 14, respectively. These conductor pieces 31 to 34 are
It is not elongated like the conductor pieces 21 to 24 used in the first embodiment, but has a size that can be accommodated in the inner wall surfaces of the protrusions 11 to 14.

The electrodes of the piezoelectric transformer 1 are taken out through the communication holes 3
This is realized by injecting a conductive adhesive 39 into 5, 36, 37 and 38. That is, the communication holes 35, 36, 3
The conductive adhesive 39 injected into the cases 7 and 38 is
Contact the conductor pieces 31, 32, 33, 34 attached to the protruding portions 11, 12, 13, 14. Thereby, each electrode of the piezoelectric transformer 1 and the conductive adhesive 39
Are electrically connected, and the respective electrodes of the piezoelectric transformer 1 are taken out.

Next, another embodiment of the present invention will be described. Embodiment 2 FIG. 5 and 6 are a perspective view showing a mounting structure of a piezoelectric transformer according to Embodiment 2 of the present invention and a vertical sectional view taken along line CC of FIG. 5, respectively. In this embodiment, the piezoelectric transformer 40 has input electrodes 42 and 43 and an output electrode 44 which are continuously formed on the side surface and the surface in order from one end side of the plate-shaped piezoelectric body 41. These input electrodes 42 and 43 and output electrode 44
Both are formed by applying a conductive paste to the piezoelectric body 41, for example.

On the other hand, the case 50 is composed of a cover member 50A that can accommodate the piezoelectric transformer 40 and a base member 50B that forms the bottom surface of the case 50. Cover member 50
On the upper surface of A, the electrodes 42, 43,
44, at each of the circular openings 5
2, 53, 54 are formed. Also, the cover member 5
The inner wall surface of 0A is coated with an insulating elastic body 55.

When the piezoelectric transformer 40 is mounted on the case 50, the piezoelectric transformer 40 is housed in the cover member 50A, and the base member 50B that covers the back side of the piezoelectric transformer 40 is bonded to the lower end of the cover member 50A with an adhesive. It is adhered by. In this manner, the piezoelectric transformer 40 is closed in the case 50 and the piezoelectric transformer 4 is closed.
The electrodes 42, 43, and 44 of the cover member 5
It is exposed from the openings 52, 53, 54 of 0A.

The electrode of the piezoelectric transformer 40 is taken out of the electrode 4
This is realized by injecting a conductive adhesive 57 into the openings 52, 53, 54 where the 2, 43, 44 are exposed, and fixing one end of the wire 56 to each conductive adhesive 57. That is, the wire 56 is connected to the openings 52, 53, 54.
Is electrically connected to the electrodes 42, 43, and 44 of the piezoelectric transformer 40 via the conductive adhesive 57 injected into the piezoelectric transformer 40, whereby each electrode of the piezoelectric transformer 40 is taken out.

In this mounting structure, since the piezoelectric transformer 40 is surrounded by the insulating elastic body 55 in the case 50, sufficient resistance to external impact can be ensured. Further, since the piezoelectric transformer 40 is mounted in the case 10 via only the insulating elastic body 15 coated on the inner wall surface of the cover member 50A, the structure is relatively small.

In the second embodiment, the electrodes are taken out only on the upper surface of the cover member 50A.
You may make it disperse | distribute to another surface and may perform it. When the piezoelectric transformer 40 is set to another vibration mode, the above-described opening may be formed at a place where the electrode can be taken out of the cover member 50A, and the electrode may be taken out. Further, in the second embodiment, the piezoelectric transformer 40 is confined in the case 50. However, by forming a hole in a part of the case 50 for communicating the inner wall surface side and the outer wall surface side of the case 50, The heat generated by the continuous driving of the piezoelectric transformer 40 may be radiated to the outside.

FIG. 7 is a perspective view showing a modification of the cover member 50A according to Embodiment 2 of the present invention from below. Here, the piezoelectric transformer 40 shown in FIG. 5 can be used as the piezoelectric transformer, and further description is omitted. In this modification, rectangular openings 62, 63, 64 are formed on the upper surface of the cover member 60 at portions corresponding to the electrodes 42, 43, 44 of the piezoelectric transformer 40, respectively. These openings 62, 63, 64 are set so as to have a larger opening area than the circular openings 52, 53, 54 shown in FIG. Cover member 5
Similarly to 0A, the inner wall surface of the cover member 60 is coated with an insulating elastic body 65.

In accordance with the use of the cover member 60, a flexible member 70 shown in FIG. 8 is used as a member for taking out the electrode to the outside of the piezoelectric transformer 40. FIGS. 8A and 8B are a plan view and a side view of the flexible member 70, respectively. The flexible member 70 is made of a conductive material, and has conductive portions 71 and 72 in which the conductive material is exposed as it is at both ends, and a conductive material coated between the conductive portions 71 and 72 with resin. And an insulating portion 73. In this embodiment, one conductive portion 71 of the flexible member is
The size and shape are set so as to fit in the openings 62, 63, and 64 formed at zero. In the mounting structure of the piezoelectric transformer 40, the flexible member 7
In a state where 0 is attached to each opening, the conductive portion 71 is electrically connected to the electrodes 42 and 43 of the piezoelectric transformer 40 via the conductive adhesive injected into each opening.

In such a configuration, the openings 62, 63, 64 formed in the cover member 60 are enlarged,
Since the contact area of the piezoelectric transformer 40 with the electrodes 42, 43, and 44 can be increased, a large current can flow through the piezoelectric transformer 40. This allows the piezoelectric transformer 40 to handle large power.

Embodiment 3 FIG. FIG. 9 is a perspective view showing a case used for the mounting structure of the piezoelectric transformer according to Embodiment 3 of the present invention. The side surface of the case 80 is composed of flat portions 81A and 81B and curved portions 82A and 82B. When the piezoelectric transformer is housed in the case 80, the flat portions 81A and 81B extend in the longitudinal direction of the piezoelectric transformer. The curved surface portions 82A and 82B
Faces the side surface along the width direction of the piezoelectric transformer. On the inner wall surfaces of the flat portions 81A, 81B, the protrusions 83A, 8 similar to the protrusions 11 to 14 in the first embodiment are provided.
3B is provided. A communication hole 84 is formed in one curved surface portion 82 </ b> B for communicating the inner wall surface side and the outer wall surface side of the case 80. Further, the inner wall surface of the case 80 is coated with an insulating elastic body 85.

In the third embodiment, conductor pieces 86A and 86B are used as members for taking out input electrodes, and each of the conductor pieces 86A and 86B has a projecting portion 83A, 83B provided on case 80 at one end thereof. Is adhered to by a conductive adhesive. Each of the conductor pieces 86A and 86B extends outward at the other end by being bent along the upper end of the case 80 in the middle thereof.

The piezoelectric transformer 90 (see FIG. 10) disposed in the case 80 having the above structure has input electrodes (not shown) corresponding to the projecting portions 83A and 83b of the case 80 along the longitudinal direction. An output electrode (not shown) corresponding to the through hole 84 of the case 80 is provided on one of the side surfaces along the width direction. Here, a case where the piezoelectric transformer is driven in the λ / 2 mode will be described as an example.

FIG. 10 shows the mounting structure of the piezoelectric transformer 90 on the case 80. In this mounting structure, the input electrode of the piezoelectric transformer 90 is taken out to the outside via the conductor pieces 86A and 86B, and the output electrode is inserted through the through hole 84 and connected to the output electrode at one end. It is taken out through a wire 92. In this mounting structure, the piezoelectric transformer 90 in the case 80 is
When subjected to vibration in the longitudinal direction of the main body, only the corners of the side surfaces come into contact with the curved surface portions 82A and 82B of the case 80, so that sufficient resistance to external impact in the longitudinal direction is obtained. As a result, the piezoelectric transformer 100
Vibration inhibition in the longitudinal direction can be suppressed,
The large electric power of the piezoelectric transformer can be handled.

As described above, in the third embodiment, the piezoelectric transformer 90 is housed in the case 80 whose side surface is formed of a flat portion and a curved portion, thereby protecting the piezoelectric transformer 90 from external impact. In addition, the piezoelectric transformer can handle large power. In the third embodiment, a conductor piece is used as a take-out member for an input electrode of a piezoelectric transformer, and a wire is used as a take-out member for an output electrode. However, the present invention is not limited to this. As an extraction member for each electrode, for example, a flexible member having conductivity may be used.

[0040]

As is apparent from the above description, according to the first aspect of the present invention, a primary electrode and a secondary electrode are formed on a piezoelectric body, and an AC voltage is applied to the primary electrode. In the mounting structure of the piezoelectric transformer which is applied and outputs a voltage from the secondary side electrode by exciting the mechanical vibration to the piezoelectric body, the piezoelectric transformer has the primary side pole and the secondary side on a side surface of the piezoelectric body. While having the electrodes, the case has, on its inner wall surface side, protrusions respectively positioned corresponding to one of the primary side electrode and the secondary side electrode, and at least one of the cases including the protrusions After the wall surface is coated with an insulating elastic body, it has a conductor piece attached to the inner surface forming the protruding portion, and in a state where the piezoelectric transformer is housed in a case, the respective electrodes are Contact the conductor piece on the case side Since the taken out to the outside through the conductor piece, it can have a large power handling of the piezoelectric transformer,
Further, it is possible to realize a mounting structure of a piezoelectric transformer having sufficient resistance to an external impact.

According to the invention of claim 2 of the present application, a primary electrode and a secondary electrode are formed on a piezoelectric body, an AC voltage is applied to the primary electrode, and a mechanical vibration is applied to the piezoelectric body. In the mounting structure of the piezoelectric transformer that outputs a voltage from the secondary electrode by being excited, the piezoelectric transformer has the primary electrode and the secondary electrode on at least one of the surfaces constituting the piezoelectric body. On the other hand, the case has an opening positioned corresponding to one of the primary electrode and the secondary electrode, and an inner wall surface of the case is coated with an insulating elastic material. While the transformer is housed in the case,
Since the piezoelectric transformer is exposed from the opening and is taken out to the outside, it is possible to handle a large amount of electric power of the piezoelectric transformer, and to realize a mounting structure of the piezoelectric transformer having sufficient resistance to external impact.

Further, according to the third aspect of the present invention, since each electrode exposed from the opening is taken out through the conductive flexible member, for example, the conductive portion of the flexible member and the opening of the case are provided. By increasing the size of the portion and increasing the contact area between them, a larger current can be passed through the piezoelectric transformer. As a result, it becomes easier to handle large power of the piezoelectric transformer.

Further, according to the invention according to claim 4 of the present application, the side surface of the case faces the side surface along the longitudinal direction of the piezoelectric transformer in a state where the piezoelectric transformer is housed in the case. Since it is composed of a flat part and a curved part facing the side surface along the width direction, it is possible to handle the large power of the piezoelectric transformer, and it has a sufficient mounting structure for the piezoelectric transformer that has sufficient resistance to external shocks. Can be realized.

[Brief description of the drawings]

FIG. 1 shows a mounting structure of a piezoelectric transformer according to a first embodiment of the present invention.

FIG. 2 shows a manufacturing process of the mounting structure of the piezoelectric transformer according to the first embodiment.

FIG. 3 shows a modification of the mounting structure of the piezoelectric transformer according to the first embodiment.

FIG. 4 shows another modification of the mounting structure of the piezoelectric transformer according to the first embodiment.

FIG. 5 shows a mounting structure of a piezoelectric transformer according to a second embodiment of the present invention.

FIG. 6 is an explanatory vertical sectional view of a mounting structure of the piezoelectric transformer according to the second embodiment.

FIG. 7 shows a modification of the case cover member according to the second embodiment.

FIG. 8 shows a flexible member used according to a modification of the case cover member according to the second embodiment.

FIG. 9 shows a case according to the third embodiment of the present invention.

FIG. 10 shows a mounting structure of a piezoelectric transformer with respect to the case according to the third embodiment.

FIG. 11 is a diagram illustrating an example of a conventional piezoelectric transformer.

FIG. 12A is a vertical cross-sectional explanatory view showing a mounting structure of a conventional piezoelectric transformer. (B) A in FIG.
FIG. 4 is an explanatory cross-sectional view taken along line -A.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Piezoelectric transformer 2, 3 ... Input electrode 4 ... Output electrode 10 ... Case 11, 12, 13, 14 ... Projection part 15 ... Insulating elastic body 21, 22, 23, 24 ... Conductor piece 25, 26, 27, 28 Slit holes 52, 53, 54 Opening 56 Wire 70 Flexible members 81A, 81B Planar portions 82A, 82B Curved portions

 ──────────────────────────────────────────────────の Continuing on the front page (72) Inventor Katsushi Takeda 1006 Kazuma Kadoma, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. F-term (reference) 5H730 AA17 ZZ19

Claims (4)

[Claims] A primary electrode and a secondary electrode are formed on a piezoelectric body, an AC voltage is applied to the primary electrode, and a mechanical vibration is excited on the piezoelectric body, so that a voltage is applied from the secondary electrode. In the mounting structure of the piezoelectric transformer, the piezoelectric transformer has the primary side electrode and the secondary side electrode on a side surface of a piezoelectric body, while the case has the primary side electrode and the secondary side on its inner wall surface side. It has projections respectively positioned corresponding to one of the side electrodes, and at least the inner wall surface of a case including the projections is coated with an insulating elastic body and attached to the inner surface forming the projections. Wherein each of the electrodes is brought into contact with the conductor piece on the case side and taken out through the conductor piece in a state where the piezoelectric transformer is housed in the case. And piezoelectric Mounting structure of Nsu. 2. A secondary electrode according to claim 1, wherein a primary electrode and a secondary electrode are formed on the piezoelectric body, and an AC voltage is applied to the primary electrode to excite mechanical vibration of the piezoelectric body. In a mounting structure of a piezoelectric transformer housed in a case, a piezoelectric transformer that outputs a voltage from the electrode enables each electrode to be taken out of the case, wherein the piezoelectric transformer has at least one of surfaces constituting a piezoelectric body. While having the primary side electrode and the secondary side electrode, the case has an opening positioned respectively corresponding to one of the primary side electrode and the secondary side electrode,
An inner wall surface of the case is coated with an insulating elastic material, and each of the electrodes is exposed from the opening and taken out to the outside while the piezoelectric transformer is housed in the case. Mounting structure of piezoelectric transformer. 3. The mounting structure of a piezoelectric transformer according to claim 2, wherein each electrode exposed from said opening is taken out via a flexible member having conductivity. 4. A side surface of the case, wherein the piezoelectric transformer is housed in the case, and a side surface facing the side surface along the longitudinal direction of the piezoelectric transformer, and a curved surface facing the side surface along the width direction. The mounting structure of the piezoelectric transformer according to claim 1, further comprising: