JP3122064B2 - Electrode connection structure of piezoelectric transformer - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an electrode connection structure for a piezoelectric transformer used as a voltage converter.

[0002]

2. Description of the Related Art In general, a piezoelectric transformer generates mechanical vibration by applying an input voltage to a vibrating section, and converts the mechanical vibration into a voltage in a power generating section and outputs the voltage. . Some electrode connection structure is required for each electrode portion formed on the surface of the vibrating portion of the piezoelectric transformer in order to externally apply an input voltage. An example of a conventional electrode connection structure of a piezoelectric transformer is disclosed in
FIG.
It is shown in (A). FIG. 9A is an explanatory view showing a conventional electrode connection structure of a piezoelectric transformer.

In the previous figure, the conventional electrode connection structure of the piezoelectric transformer 101 is such that a flexible metal wire having a predetermined diameter is soldered as a lead wire 102 to each position of a vibration node on the electrode surface of the piezoelectric transformer 101. The piezoelectric transformer 101 to which the lead wire 102 is soldered is housed between the upper and lower cases 103 and 104 made of plastic and accommodated in a loose fit state. The lead wire 102 is drawn out of the through holes 103a, 104a, which are sufficiently larger than the lead wire diameter provided in the upper and lower cases 103, 104, and connected to an electronic circuit (not shown).

Another example of the conventional electrode connection structure of a piezoelectric transformer is disclosed in Japanese Patent Application Laid-Open No. 7-79027, which is shown in FIG. 9 (B). FIG. 9B is an explanatory view showing another conventional electrode connection structure of a piezoelectric transformer.

In the previous figure, another conventional piezoelectric transformer 20 is shown.
The first electrode connection structure is such that a support portion is provided at each position of the vibration node portions P1 and P2 on the electrode surface of the piezoelectric transformer 201, at least the surface of which is made of a conductor such as a metal and protrudes above the insulating plate 202. The piezoelectric transformer 201 is configured to be in contact with and electrically connected to the respective electrodes, sandwich the piezoelectric transformer 201 between the upper and lower insulating plates 202, and support the piezoelectric transformer 201 with the support portions 203. An external lead-out electrode 203a is led out from the support part 203, drawn out to the back surface of each insulating plate 202, and connected to an electronic circuit (not shown).

[0006]

Since the conventional electrode connecting structure of the piezoelectric transformer is configured as described above,
In the former case, when wiring is performed by soldering to each electrode of the vibrating portion of the piezoelectric transformer 101, deterioration of the piezoelectric transformer 101 due to heat of soldering, that is, a change in characteristics is inevitable, and wiring and assembly are troublesome. There is a problem that the manufacturing cost is high. In addition, there is a problem that the soldered portion may be peeled off by the stress due to the vibration of the piezoelectric transformer 101 or an external impact.

On the other hand, in the latter case, the piezoelectric transformer 201
Due to the unevenness of the surface, the actual contact state of the flat support portion 203 surface with the piezoelectric transformer 201 becomes close to a point contact, a sufficient contact area cannot be obtained, the contact resistance increases, and the input voltage is wasted. There was a problem of doing it. Furthermore, the contact between the fixed support portion 203 and the piezoelectric transformer 201 causes wear of the contact portion of the piezoelectric transformer 201, and changes in environmental conditions such as input conditions (drive voltage and the like), output conditions (load and the like), and temperature fluctuations. The frequency of the piezoelectric transformer 201 changes with the
However, even if the physical position of the vibrating node changes, the fixed supporting portion 203 cannot cope with the changed vibrating node, and acts to suppress the vibration of the piezoelectric transformer 201, and the performance decreases. Had the problem that

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problem, and eliminates the cause of a change in the characteristics of a piezoelectric transformer, and has a simple structure, which can improve reliability, can be easily assembled, and can be manufactured at low cost. Yes, and can always support the vibration node with appropriate degrees of freedom regardless of changes in vibration conditions.
An object of the present invention is to provide an electrode connection structure of a piezoelectric transformer that can always maintain a predetermined performance.

[0009]

An electrode connecting structure for a piezoelectric transformer according to the present invention contacts a vibrating node or a position near the vibrating node on an electrode surface of a vibrating portion of the piezoelectric transformer, and holds the piezoelectric transformer from both sides. In the electrode connection structure of the piezoelectric transformer having a contact terminal portion at least the surface of which is electrically connected and made of a conductive material, a contact portion of the contact terminal portion with the piezoelectric transformer has elasticity,
The piezoelectric transformer is formed by being divided into a plurality of pieces in the width direction of the piezoelectric transformer, and becomes a plurality of contact pieces that individually contact the piezoelectric transformer electrode surfaces. As described above, according to the present invention, the contact portion of the contact terminal portion electrically connected to the electrode surface of the piezoelectric transformer is divided into a plurality of pieces in the width direction of the piezoelectric transformer to form a plurality of contact pieces, and the By increasing the density and the followability, even when the electrode surface has irregularities, each contact piece can secure a sufficient contact area corresponding to the electrode surface, the contact resistance does not increase, and the efficiency can be improved. . In addition, assembling can be easily performed with a simple structure, cost can be reduced, and the reliability can be improved without the need for soldering, and there is no deterioration in performance of the piezoelectric transformer or disconnection due to vibration.

[0010] The electrode connecting structure of the piezoelectric transformer according to the present invention may include a support member having a groove parallel to the width direction of the piezoelectric transformer formed in a portion substantially corresponding to a vibration node of the piezoelectric transformer as necessary. The contact terminal portion is a substantially coil-shaped member made of a continuous elastic filament member so as to form a substantially cylindrical surface having a predetermined diameter, and is inserted into the groove portion of the support member in a state where a part of the outer periphery is exposed outside the groove. It is to be arranged. As described above, according to the present invention, the contact terminal portion is formed as a substantially coil-shaped member, and is held in the groove of the support member provided with the piezoelectric transformer interposed therebetween so as to sandwich the vibration node portion of the piezoelectric transformer. Even if there are irregularities on the electrode surface, each coil-shaped stage is provided as a plurality of contact pieces arranged in the width direction of the piezoelectric transformer, so that it can be reliably brought into contact with the electrode surface, regardless of the surface condition of the piezoelectric transformer. An area can be secured to suppress an increase in contact resistance and increase efficiency. Further, the use of a simple and easy-to-mold structure can further reduce costs and improve reliability.

In the electrode connecting structure for a piezoelectric transformer according to the present invention, if necessary, the width of the groove of the support member is formed to have a predetermined width larger than the diameter of a substantially cylindrical surface formed by the contact terminal portion. A terminal portion is rotatably disposed in the groove of the support member. As described above, according to the present invention, the width of the groove portion of the support member is increased, and the contact terminal portion is rotatable and movable in the groove portion. The contact terminal moves within the groove and can easily cope with a new vibration node of the piezoelectric transformer even when the vibration node position on the piezoelectric transformer is caused. Does not hinder vibration and does not cause performance degradation. Also, since the contact terminal is movable with respect to the piezoelectric transformer,
The contact points of the piezoelectric transformer with the contact terminals are dispersed without being concentrated on a specific point, and the piezoelectric transformer is less likely to be worn.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION

(First Embodiment of the Present Invention) Hereinafter, a first embodiment of the present invention will be described with reference to FIGS. This figure 1
2 is a plan view showing an electrode connection structure of the piezoelectric transformer according to the embodiment, and FIG. 2 is a schematic configuration perspective view of a contact terminal portion in the electrode connection structure of the piezoelectric transformer according to the embodiment.

In each of the drawings, the electrode connecting structure of the piezoelectric transformer according to the present embodiment is a rectangular plate-shaped piezoelectric transformer 1.
1. A substrate 12 having a mounting opening 12a having a size that can be accommodated with a gap around the width direction and the longitudinal direction of the substrate 12, and the front and back of the substrate 12 with the mounting opening 12a of the substrate 12 interposed therebetween. Arranged on both sides, one end has a plurality of contact pieces 1
A contact terminal 13 having a contact 3a formed thereon. The contact terminal 13 contacts each contact piece 13a with a predetermined pressure at an electrode surface of a vibrating portion of the piezoelectric transformer 11 and at a vibration node position. 11 is held so as to be able to vibrate.

The piezoelectric transformer 11 is a well-known voltage conversion element formed in the shape of an elongated rectangular plate, and has an input electrode 11a and an earth, which are opposed to both upper and lower surfaces at one end in the longitudinal direction up to approximately half the length of the rectangular plate. An electrode (not shown) is formed on each side, and an output electrode (not shown) is formed on the side surface on the other end side. The gap between the input electrode 11a and the ground electrode is in the thickness direction, and the other portions are longitudinal. In this configuration, polarization processing is performed in the directions to become a vibrating unit and a power generating unit, respectively. Drive is λ
Using the resonance of the mode, the length from both ends is 1/4 of the total length
Are the vibration nodes.

The substrate 12 is a printed wiring board provided with a substantially rectangular hole-shaped mounting opening 12a. The mounting opening 12a is provided with an appropriate gap in the width and longitudinal directions of the piezoelectric transformer 11. It is configured to be drilled with a larger dimension. In particular, in the longitudinal direction of the mounting opening 12a, a predetermined gap is set so that the piezoelectric transformer 11 can move along with the displacement of the vibrating node due to a change in the frequency, so that the vibration of the piezoelectric transformer 11 is not restricted. I have.

The contact terminal portion 13 is made of a thin metal plate having flexibility and elasticity. One end portion of the contact terminal portion 13 projects in a substantially mountain shape, is bent, and is divided into a plurality in the width direction of the piezoelectric transformer 11. And formed as a plurality of contact pieces 13a. The contact piece 13a shows the bending curve of the piezoelectric transformer 11
In a direction parallel to the width direction of the piezoelectric transformer 11, and comes into line contact with the vibration node position on the surface of the vibration section of the piezoelectric transformer 11.

In a state where the above-described members are assembled,
A pair of contact terminals 13 are integrally attached to the substrate 12 at the other end by soldering or the like, and are connected to an electronic circuit (not shown) on the substrate 12. 11 is sandwiched from both sides of the mounting opening 12a. And each contact piece 13 of the contact terminal portion 13
At a point a, the piezoelectric transformer 11 is sandwiched and supported at a plurality of positions in the width direction, and at the same time, each contact piece 13a is electrically connected to the input electrode 11a or the ground electrode.

Next, an operation state of the piezoelectric transformer based on the above configuration will be described. When a predetermined AC voltage is applied to the piezoelectric transformer 11 from an electronic circuit on the substrate 12 connected thereto, a vibration of a predetermined frequency is generated in a vibrating portion sandwiched between the input electrode 11a and the ground electrode of the piezoelectric transformer 11, and The vibration is converted into a predetermined high voltage in the power generation unit and output. At this time, in the contact terminal section 13, the plurality of contact pieces 13a are in contact with the respective electrode surfaces of the piezoelectric transformer 11 to maintain a sufficient contact area even during vibration, and the piezoelectric transformer 11 Can be applied to the input voltage.

As described above, in the electrode connecting structure of the piezoelectric transformer according to the present embodiment, the contact portion of the contact terminal portion 13 is divided into a plurality of pieces in the width direction of the piezoelectric transformer 11 to form a plurality of contact pieces 13a. 11 can be brought into contact with each other by increasing the contact density and the ability to follow the surface in the width direction of each of the contact pieces 13 even if the electrode surface has irregularities.
a can reliably contact the electrode surface to secure a sufficient contact area, and the voltage conversion efficiency can be increased without the contact area becoming extremely small and the contact resistance increasing. In addition, it is easy to assemble with a simple structure that does not require soldering to the piezoelectric transformer 11, and cost reduction can be achieved. Also, there is no deterioration in performance of the piezoelectric transformer 11 or disconnection due to vibration, etc., and reliability is greatly improved. Let me do.

(Second Embodiment of the Present Invention) A second embodiment of the present invention will be described with reference to FIG. FIG. 3 is a plan view and a longitudinal sectional view showing an electrode connection structure of the piezoelectric transformer according to the present embodiment.

In FIG. 3, the electrode connecting structure of the piezoelectric transformer according to the present embodiment is similar to that of the first embodiment in that the piezoelectric transformer 21 is provided in the mounting opening 22a of the substrate 22.
On the other hand, as a different configuration, a configuration is provided in which a coil is used instead of the metal plate as the contact terminal portion 23.

The coil forming the contact terminal portion 23 has an outer peripheral portion, which forms a circumferential surface of a helically wound metal elastic wire member, at a vibrating node position of each vibrating portion of the vibrating portion of the piezoelectric transformer 21. By contacting each of the spiral stages that contact the piezoelectric transformer 21, a plurality of contact pieces 23 arranged at a predetermined pitch are provided.
a. The contact terminals 23 are disposed in a direction parallel to the width direction of the piezoelectric transformer 21 and sandwich the piezoelectric transformer 21 so as to be able to vibrate.

In a state where the above-mentioned members are assembled,
A pair of contact terminals 23 are integrally attached to the substrate 22 at both ends by soldering or the like, and are connected to an electronic circuit (not shown) on the substrate 22. From both sides of the mounting opening 22a. The piezoelectric transformer 21 is sandwiched and supported at a plurality of positions in the width direction by the contact pieces 23a, which are the spiral stages of the contact terminal portion 23, and at the same time, each contact piece 23a and the input electrode 21a or the ground electrode (not shown) are formed. Are electrically connected.

Next, an operation state of the piezoelectric transformer based on the above configuration will be described. When a predetermined AC voltage is applied to the piezoelectric transformer 21 from an electronic circuit on the substrate 22 connected thereto, a vibration of a predetermined frequency is generated in a vibrating portion between the input electrode 21a and the ground electrode of the piezoelectric transformer 21. The vibration is converted into a predetermined high voltage in the power generation unit and output. At this time, in the contact terminal section 23, the plurality of contact pieces 23a are in contact with the respective electrode surfaces of the piezoelectric transformer 21 to maintain a sufficient contact area even during vibration, and the piezoelectric transformer 21 Can be applied to the input voltage.

As described above, in the electrode connecting structure of the piezoelectric transformer according to the present embodiment, a plurality of coil stages are arranged in the width direction of the piezoelectric transformer 21 with the contact portion of the contact terminal portion 23 as the outer peripheral portion of the coil. The contact piece 23a is provided, and even if the electrode surface has irregularities, each contact piece 23a can be reliably brought into contact with the electrode surface, so that a sufficient contact area is ensured regardless of the surface condition of the piezoelectric transformer 21. Suppress resistance rise and increase efficiency. Also, the contact terminal portion 2
By using a coil having a simple structure as 3, the cost can be further reduced and the reliability can be improved.

(Third Embodiment of the Present Invention) A third embodiment of the present invention will be described with reference to FIG. FIG. 4 is a plan view and a longitudinal sectional view showing an electrode connection structure of the piezoelectric transformer according to the present embodiment.

In FIG. 4, the electrode connecting structure of the piezoelectric transformer according to the present embodiment is similar to that of the first embodiment in that the piezoelectric transformer 31 is provided in the mounting opening 32a of the substrate 32.
On the other hand, the mounting opening 3
Two thin plates 33 as support members, which are provided on both front and back sides of the substrate 32 with 2a interposed therebetween, and in which a groove 33a is formed corresponding to a vibration node position of each electrode surface in a vibration portion of the piezoelectric transformer 31; A contact terminal portion 34 of a coil inserted and arranged in a groove portion 33a of the thin plate 33;
Are sandwiched between thin plates 33 in a substantially sandwich shape, and contact terminal portions 34
Is in contact with the position of the vibration node on the electrode surface of the vibrating portion of the piezoelectric transformer 31 to support the piezoelectric transformer 31 so that it can vibrate.

The thin plate 33 is formed of a thin plate having flexibility and elasticity, has a size to cover the mounting opening 32a, is disposed on the front and back of the substrate 32, and faces the piezoelectric transformer 31. A groove 33a is provided at a position corresponding to the vibration node position (or a position near the vibration node) of the vibration section of the piezoelectric transformer 31.
Are formed respectively. This groove 33a is
The contact terminal portion 34 is formed with a width larger than the diameter of the cylinder formed by the coil, and the contact terminal portion 34 is rotatable in the groove 33a and movable in the groove width direction.

The contact terminal portion 34 is disposed between the groove portion 33a and the piezoelectric transformer 31, and an outer peripheral portion thereof is brought into contact with each electrode surface of the vibrating portion of the piezoelectric transformer 31,
In this configuration, each spiral stage that comes into contact with the piezoelectric transformer 31 is formed by a plurality of contact pieces 34a arranged at a predetermined pitch. The contact terminals 34 are electrically connected to an electronic circuit (not shown) on the substrate 32 via a wiring pattern (not shown) provided on the thin plate 33.

In a state where the above-described members are assembled,
A pair of thin plates 33 are integrally attached to the substrate 32 with an adhesive or a double-sided tape, and at the same time, the piezoelectric transformer 31 is sandwiched from both front and back sides of the attachment opening 32a via the contact terminals 34 provided in the groove 33a. . The piezoelectric transformer 31 is sandwiched and supported at a plurality of positions in the width direction by the contact pieces 34a, which are spiral tiers of the contact terminal portion 34 held by the groove 33a of the thin plate 33, and at the same time, each contact piece 34a and the input electrode 31 are supported.
a or the ground electrode is electrically connected.

Next, an operation state of the piezoelectric transformer based on the above configuration will be described. When a predetermined AC voltage is applied to the piezoelectric transformer 31 from an electronic circuit on the board 32 connected thereto, a vibration of a predetermined frequency is generated in a vibrating portion between the input electrode 31a and the ground electrode of the piezoelectric transformer 31. The vibration is converted into a predetermined high voltage in the power generation unit and output. At this time, in the contact terminal section 34, the plurality of contact pieces 34a are in contact with the respective electrode surfaces of the piezoelectric transformer 31 to maintain a sufficient contact area even during vibration, and the piezoelectric transformer 31 Can be applied to the input voltage. Further, even if a change in the frequency occurs due to a change in environmental conditions or the like, and the position of the vibration node on the piezoelectric transformer 31 moves, the contact terminal portion 34 is not affected.
Moves in the groove 33a, and can correspond to a new vibration node position of the piezoelectric transformer 31.

As described above, in the electrode connecting structure of the piezoelectric transformer according to the present embodiment, the vibrating portion of the piezoelectric transformer 31 is held by the thin plate 33 via the contact terminal portion 34, and the inside of the groove 33a of the thin plate 33 is formed. Since the contact terminal portion 34 is movable, the contact terminal portion 34 moves in the groove 33a to move the vibration node portion on the piezoelectric transformer 31 due to the frequency change. Can easily cope with a new vibrating node portion, and the contact terminal portion 34 restrains a portion other than the vibrating node portion so that the piezoelectric transformer 31
It does not hinder the vibration of the device and does not cause a decrease in performance. Further, since the contact terminal portion 34 can move with respect to the piezoelectric transformer 31, the contact portion of the piezoelectric transformer 31 with the contact terminal portion 34 does not concentrate on a specific portion, and the piezoelectric transformer 31
Surface wear is less likely to occur.

(Fourth Embodiment of the Present Invention) A fourth embodiment of the present invention will be described with reference to FIG. FIG. 5 is an exploded perspective view showing the electrode connection structure of the piezoelectric transformer according to the present embodiment.

In FIG. 5, the electrode connecting structure of the piezoelectric transformer according to the present embodiment uses a metal plate-like contact terminal portion 44 similarly to the first embodiment, but has a different structure from the substrate The case 43 has a configuration in which the piezoelectric transformer 41 and the contact terminal portion 44 are housed in a case 43 provided on the case 42.

The case 43 is a plastic molded body obtained by combining an upper case 43a and a lower case 43b.
A hollow portion capable of accommodating the piezoelectric transformer 41 with a suitable gap around the piezoelectric transformer 41 is formed therein.

The upper and lower surfaces of the hollow portion correspond to the vibrating nodes of the power generating unit of the piezoelectric transformer 41, and the inner surfaces in the width direction of the hollow portions correspond to the vibrating nodes of the piezoelectric transformer 41. A piezoelectric transformer 41 is provided on the inner surface of the hollow piezoelectric transformer 41 in the longitudinal direction on the vibrating part side.
In this configuration, a columnar support 43c is provided so as to be able to abut on the surface of the first support member 1. These support members 43c are made of rubber having appropriate elasticity, and the ends of the peripheral side surfaces thereof come into contact with the surface of the piezoelectric transformer 41 by line contact (or point contact), and the piezoelectric transformer 41 is vibrated to a predetermined position in the case 43. It will be held freely.

In a state where the above-described members are assembled,
The piezoelectric transformer 41 and the contact terminal portion 44 are housed in a case 43 in which the upper case 43a and the lower case 43b are integrally combined with an adhesive or a double-sided tape, and the contact terminal portion 44 holds the piezoelectric transformer 41 from both sides. Is done. Here, the piezoelectric transformer 41 is sandwiched and supported at a plurality of positions in the width direction by the respective contact pieces 44a of the contact terminal portion 44, and at the same time, each contact piece 44a is electrically connected to the input electrode 41a or the ground electrode. Becomes Furthermore, case 43
Are integrally attached to the substrate 42 with an adhesive or a double-sided tape, and the end of each contact terminal portion 44 is connected to an electronic circuit (not shown) of the substrate 42.

Next, an operation state of the piezoelectric transformer based on the above configuration will be described. When a predetermined AC voltage is applied to the piezoelectric transformer 41 from an electronic circuit on the board 42 connected to the piezoelectric transformer 41, a vibration of a predetermined frequency is generated in a vibration portion sandwiched between the input electrode 41a and the ground electrode of the piezoelectric transformer 41. The vibration is converted into a predetermined high voltage in the power generation unit and output. At this time, in the contact terminal portion 44, the plurality of contact pieces 44a are in contact with the respective electrode surfaces of the piezoelectric transformer 41 to maintain a sufficient contact area even during vibration, and the piezoelectric transformer 41 does not cause a contact failure or the like. Can be applied to the input voltage.

As described above, in the electrode connecting structure of the piezoelectric transformer according to the present embodiment, the contact portion of the contact terminal portion 44 is divided into a plurality of pieces in the width direction of the piezoelectric transformer 41 to form a plurality of contact pieces 44a. Since the contact can be made while increasing the contact density and the surface followability in the width direction of the contact 41, even if the electrode surface has irregularities, each contact piece 44
a can reliably contact the electrode surface to secure a sufficient contact area, and the voltage conversion efficiency can be increased without the contact area becoming extremely small and the contact resistance increasing. In addition, assembling can be easily performed with a simple structure that does not require soldering to the piezoelectric transformer 41, cost reduction can be achieved, and there is no disconnection due to performance deterioration or vibration of the piezoelectric transformer 41, and reliability is greatly improved. Let me do.

(Fifth Embodiment of the Present Invention) A fifth embodiment of the present invention will be described with reference to FIG. FIG. 6 is an exploded perspective view showing the electrode connection structure of the piezoelectric transformer according to the present embodiment.

Referring to FIG. 6, the electrode connecting structure of the piezoelectric transformer according to the present embodiment is different from the fourth embodiment in that the piezoelectric transformer 51 is disposed in a case 53 on a substrate 52, while having a different configuration. A groove 53d is formed corresponding to the position of the vibrating node of each electrode surface in the vibrating portion of the piezoelectric transformer 51 of the case 53.
Terminal 54 of the coil inserted and arranged in the groove 53d
A configuration in which the piezoelectric transformer 51 is sandwiched in a substantially sandwich shape by the case 53, the contact terminal portion 54 abuts on a vibration node portion of the electrode surface of the vibrating portion of the piezoelectric transformer 51, and the piezoelectric transformer 51 is oscillated. It is.

In the case 53, a coil serving as a contact terminal portion 54 is inserted and disposed at a position facing the piezoelectric transformer 51 and corresponding to a vibration node position of a vibration portion of the piezoelectric transformer 51 (or a position in the vicinity thereof). The configuration is such that grooves 53d are respectively formed.

The contact terminal portion 54 is provided between the groove 53d and the piezoelectric transformer 51, and the outer peripheral portion thereof is brought into contact with each electrode surface of the vibrating portion of the piezoelectric transformer 51,
In this configuration, each spiral stage that comes into contact with the piezoelectric transformer 51 is constituted by a plurality of contact pieces 54a arranged at a predetermined pitch. The contact terminals 54 are electrically connected to electronic circuits (not shown) on the substrate 52 at both ends penetrating the case 53.

In a state where the above-mentioned members are assembled,
The piezoelectric transformer 51 and the contact terminal portion 54 are housed in a case 53 in which the upper case 53a and the lower case 53b are integrally combined by an adhesive or a double-sided tape.
The piezoelectric transformer 5 is connected to the piezoelectric transformer 5
Hold 1 from both sides. Here, the piezoelectric transformer 51 is sandwiched and supported at a plurality of positions in the width direction by the contact pieces 54a, which are the spiral stages of the contact terminal portion 54, and at the same time, each contact piece 54a
a is electrically connected to the input electrode 51a or the ground electrode. Further, the case 53 is integrally attached to the substrate 52 with an adhesive or a double-sided tape, and at the same time, each contact terminal portion 54 is connected to the electronic circuit of the substrate 52.

Next, the operation state of the piezoelectric transformer based on the above configuration will be described. When a predetermined AC voltage is applied to the piezoelectric transformer 51 from an electronic circuit on the board 52 connected to the piezoelectric transformer 51, a vibration of a predetermined frequency is generated in a vibrating portion sandwiched between the input electrode 51a and the ground electrode of the piezoelectric transformer 51. The vibration is converted into a predetermined high voltage in the power generation unit and output. At this time, in the contact terminal portion 54, the plurality of contact pieces 54a are in contact with the respective electrode surfaces of the piezoelectric transformer 51 to maintain a sufficient contact area even during vibration, and the piezoelectric transformer Can be applied to the input voltage.

As described above, in the electrode connecting structure of the piezoelectric transformer according to the present embodiment, a plurality of coil stages are arranged in the width direction of the piezoelectric transformer 51 with the contact portion of the contact terminal portion 54 as the outer peripheral portion of the coil. The contact piece 54a is formed, and even if the electrode surface has irregularities, each contact piece 54a can be reliably brought into contact with the electrode surface, so that a sufficient contact area is secured regardless of the surface condition of the piezoelectric transformer 51. Suppress resistance rise and increase efficiency. In addition, the contact terminal portion 5
By using a coil having a simple structure as 4, the cost can be further reduced and the reliability can be improved.

In the electrode connecting structure of the piezoelectric transformer according to the fifth embodiment, the contact terminal 54 is fixed in the groove 53d. However, as in the third embodiment. The groove 53d may be formed to have a width larger than the cylindrical diameter of the coil serving as the contact terminal 54, and the contact terminal 54 may be rotatable within the groove 53d and movable in the groove width direction. The contact terminal portion 54 moves in the groove 53d even when the position of the vibration node on the piezoelectric transformer 51 is moved due to the frequency fluctuation, so that it can easily cope with a new vibration node. In addition, the performance of the piezoelectric transformer 51 does not deteriorate, and the contact point of the piezoelectric transformer 51 with the contact terminal portion 54 does not concentrate on a specific place, so that the piezoelectric transformer 51 is hardly worn. And
The connection between the contact terminal portion 54 and the substrate 52 in this case is shown in FIG.
As shown in (1), a configuration in which the process is performed via a plate-shaped conductive member 55 can be adopted.

In the electrode connecting structure of the piezoelectric transformer according to each of the third and fifth embodiments, the contact terminal portion is a coil. However, the present invention is not limited to this. As shown in FIG. A predetermined-shaped plate member having a plurality of striated portions may be bent into a cylindrical shape and used as a substantially coil-shaped member, thereby simplifying the manufacturing process and achieving further cost reduction.

Further, in the electrode connecting structure of the piezoelectric transformer according to each of the third, fourth and fifth embodiments, the space for accommodating the piezoelectric transformer is sealed, and inert gas such as nitrogen gas is contained in the space. A configuration in which a gas is sealed can be adopted, and oxidation of the contact terminal portion can be prevented, thereby further improving reliability.

Further, in each of the first to fifth embodiments, the piezoelectric transformer of the type having two vibrating nodes has been described as an example. However, the present invention is not limited to the above embodiments. The present invention is also applicable to a piezoelectric transformer of a type having another vibration pattern, for example, a tertiary Rosen (three vibration nodes are generated) type piezoelectric transformer.

[0051]

As described above, according to the present invention, a plurality of contact pieces are formed by dividing a contact portion of a contact terminal portion electrically connected to an electrode surface of a piezoelectric transformer into a plurality of pieces in the width direction of the piezoelectric transformer. By increasing the contact density and followability with respect to the electrode surface, even when the electrode surface has irregularities, each contact piece can secure a sufficient contact area corresponding to the electrode surface, and the contact resistance does not increase, This has the effect of improving efficiency. In addition, the structure can be easily assembled with a simple structure, cost can be reduced, and there is no need for soldering to the piezoelectric transformer, so that the performance of the piezoelectric transformer is not degraded and there is no disconnection due to vibration, so that reliability is improved. . Further, in the present invention, the contact terminal portion is a substantially coil-shaped member, and the contact terminal portion is held in a groove portion of a support member disposed to sandwich the piezoelectric transformer and sandwiches the vibration node portion of the piezoelectric transformer, thereby forming a substantially coil-shaped member. Even if there are irregularities on the electrode surface as a plurality of contact pieces arranged in the width direction of the piezoelectric transformer, each stage can be reliably brought into contact with the electrode surface,
There is an effect that a sufficient contact area is ensured irrespective of the surface state of the piezoelectric transformer to suppress an increase in contact resistance and increase efficiency. Further, the use of a simple and easy-to-mold structure has the effect of further reducing costs and improving reliability. Further, in the present invention, the width of the groove of the support member is increased, and the contact terminal is movable in the groove. The contact terminal moves in the groove and can easily cope with a new vibration node of the piezoelectric transformer even if the position of the vibration node is moved. Has the effect of not causing Furthermore, since the contact terminals are movable with respect to the piezoelectric transformer, the contact points of the piezoelectric transformer with the contact terminals are dispersed without concentrating on a specific location, and the piezoelectric transformer is less likely to be worn. Having.

[Brief description of the drawings]

FIG. 1 is a plan view showing an electrode connection structure of a piezoelectric transformer according to a first embodiment of the present invention.

FIG. 2 is a schematic configuration perspective view of a contact terminal portion in the electrode connection structure of the piezoelectric transformer according to the first embodiment of the present invention.

FIG. 3A is a plan view showing an electrode connection structure of a piezoelectric transformer according to a second embodiment of the present invention. (B) is a longitudinal sectional view showing an electrode connection structure of a piezoelectric transformer according to a second embodiment of the present invention.

FIG. 4A is a plan view showing an electrode connection structure of a piezoelectric transformer according to a third embodiment of the present invention. (B) is a longitudinal sectional view showing an electrode connection structure of a piezoelectric transformer according to a third embodiment of the present invention.

FIG. 5 is an exploded perspective view showing an electrode connection structure of a piezoelectric transformer according to a fourth embodiment of the present invention.

FIG. 6 is an exploded perspective view showing an electrode connection structure of a piezoelectric transformer according to a fifth embodiment of the present invention.

FIG. 7 is an essential part exploded perspective view showing another example of the electrode connection structure of the piezoelectric transformer according to the fifth embodiment of the present invention.

FIG. 8 is a schematic structural explanatory view of another contact terminal portion in an electrode connection structure of a piezoelectric transformer according to a fifth embodiment of the present invention.

FIG. 9A is a cross-sectional view showing a conventional electrode connection structure of a piezoelectric transformer. (B) is an exploded perspective view showing another conventional electrode connection structure of a piezoelectric transformer.

[Explanation of symbols]

11, 21, 31, 41, 51, 101, 201 Piezoelectric transformers 11a, 21a, 31a, 41a, 51a Input electrodes 12, 22, 32, 42, 52 Substrates 12a, 22a, 32a Mounting openings 13, 23, 34, 44, 54 Contact terminal part 13a, 23a, 34a, 44a, 54a Contact piece 33 Thin plate 33a, 53d Groove part 43, 53 Case 43a, 53a, 103 Upper case 43b, 53b, 104 Lower case 43c, 53c Support 55 Conductive member 102 Lead wire 103a, 104a Free through hole 202 Insulating plate 203 Support 203a External lead-out electrode

Claims (3)

(57) [Claims] A contact is made between a vibrating node portion or a position near the vibrating node portion on an electrode surface of a vibrating portion of a piezoelectric transformer, the piezoelectric transformer is sandwiched from the front and back, and at least the surface electrically connected is made of a conductive material. In the electrode connecting structure of a piezoelectric transformer having a terminal portion, a contact portion of the contact terminal portion with the piezoelectric transformer has elasticity and is formed by being divided into a plurality of pieces in the width direction of the piezoelectric transformer, and each of the piezoelectric transformer electrodes is independently formed. An electrode connection structure for a piezoelectric transformer, comprising a plurality of contact pieces that come into contact with a surface. 2. The electrode connecting structure for a piezoelectric transformer according to claim 1, further comprising: a support member having a groove parallel to a width direction of the piezoelectric transformer formed at a portion substantially corresponding to a vibration node of the piezoelectric transformer. The contact terminal portion is a substantially coil-shaped member made of an elastic linear member that is continuous to form a substantially cylindrical surface having a predetermined diameter, and is inserted and arranged in the groove portion of the support member with a part of the outer periphery exposed outside the groove. An electrode connection structure for a piezoelectric transformer, which is provided. 3. The electrode connection structure for a piezoelectric transformer according to claim 2, wherein the width of the groove of the support member is formed to have a predetermined width larger than the diameter of a substantially cylindrical surface formed by the contact terminal. An electrode connection structure for a piezoelectric transformer, wherein the portion is rotatably disposed in the groove of the support member.