JP5576013B2 - Piezoelectric transformer - Google Patents

Description

  The present invention relates to a piezoelectric transformer that applies an input voltage to a piezoelectric body and obtains a transformed output voltage by utilizing the mechanical vibration.

As a prior art related to this type of piezoelectric transformer, one having a structure in which a piezoelectric transformer main body is accommodated in a box-shaped case having an open bottom is known (for example, see Patent Document 1). In this prior art, the primary and secondary pin terminals are provided in the case, the primary electrode and the primary pin terminal formed on the outer surface of the piezoelectric transformer body, and the secondary electrode and the secondary side Each pin terminal is connected via a gold thread wire.
JP 2006-108332 A (FIG. 7)

  The prior art piezoelectric transformer can be mounted on the circuit board through the case. When an input voltage is applied to the piezoelectric transformer body through the primary-side pin terminal, mechanical vibration is generated in the piezoelectric transformer body within the case, and the boosted voltage is output through the secondary-side pin terminal. A gold thread wire is a structure in which a copper foil is wound around a core material made of a large number of fine wires in a rope shape, so even if mechanical vibration repeatedly occurs in the piezoelectric transformer body, it flexibly follows it. Can assure stable operation over a long period of time.

  As described above, the prior art is a preferable example of the structure of the piezoelectric transformer, and the piezoelectric transformer main body is accommodated in the case so that it is excellent in handling at the time of mounting work. Therefore, it is excellent in that it has sufficient durability for long-term use.

  In addition, the present invention has been made with an object of providing a technique capable of improving the practicality while taking advantage of the prior art.

  The piezoelectric transformer of the present invention has a piezoelectric body having an electrode formed on the outer surface, and a terminal disposed so as to face the electrode, and in particular, two types of elasticity between the electrode and the terminal of the piezoelectric body. This is a structure in which members are arranged. Among these, the first elastic member has conductivity, and can contact both of the electrodes and the terminals to make them conductive with each other. The second elastic member is disposed between the electrode and the terminal of the piezoelectric body together with the first elastic member, and holds the first elastic member in contact with at least one of the electrode and the terminal. is there.

  According to the above-described structure, the electrical connection between the electrode of the piezoelectric body and the terminal is realized via the first elastic member. Since the first elastic member itself has elasticity as well as conductivity, the first elastic member can flexibly follow the mechanical vibration of the piezoelectric body while achieving conductivity. In addition, the present invention employs a structure in which the first elastic member is held by the second elastic member. For example, when a conductive material is mixed into an elastic member such as rubber, the mechanical strength of the material may be reduced. In the present invention, the first elastic member is held by the second elastic member. Compared with the structure using the first elastic member alone, the mechanical strength can be further improved.

  On the other hand, according to the structure of the present invention, since the necessary conductivity is achieved by the first elastic member and this is held by the second elastic member, the first and second elastic members are combined. It is possible to reduce the ratio and absolute amount of the conductive material occupying the entire size and capacity. For example, regarding the total size of the first and second elastic members combined, when the size that can ensure the ease of handling at the time of assembling the piezoelectric transformer is 100, the ratio of the first elastic member occupying the size is 100%. If it is made as small as possible (however, it is greater than 0), the amount of the conductive material used can be reduced as a whole. Since the amount of the conductive material used is greatly reflected in the cost, there is an advantage that reducing the amount used greatly contributes to reducing the manufacturing cost of the piezoelectric transformer.

  More preferably, a structure in which the piezoelectric body is accommodated in the case is employed in the present invention. In this case, the outside of the case (for example, the wiring pattern on the circuit board) can be electrically connected to the piezoelectric body through the terminal. The terminal is the same as the above in that the terminal is arranged facing the electrode in a state where the piezoelectric body is accommodated in the case.

  The first and second elastic members are press-fitted between the electrodes of the piezoelectric body and the terminals in the case. In this case, the first elastic member can be brought into strong contact with both the electrode and the terminal by the repulsive force, and the electrical resistance at the contact surface can be reduced and the both can be conducted more reliably. Therefore, even if the capacity and size of the first elastic member are made as small as possible, sufficient electrical conduction can be achieved with a strong crimping force, so that the amount of conductive material used can be further reduced. In addition, the second elastic member strongly adheres to the electrode and the terminal by its repulsive force, so that the piezoelectric body that vibrates in the case can be reliably supported.

  The first and second elastic members described above may have a laminated structure in which the first and second elastic members are alternately overlapped when viewed in the longitudinal direction defined by the terminals. In this case, since each of the layers intersects with the longitudinal direction of the terminal, all the layers of the first elastic member having conductivity can be brought into contact with the terminal, and the electrical continuity thereof. Can be achieved reliably.

More practical forms of the present invention are provided below.
That is, in the piezoelectric body, primary electrodes are formed on two outer surfaces that make a pair with each other, and secondary electrodes are formed on the outer surface at positions different from these primary electrodes. The piezoelectric body is accommodated in a case, and a plurality of terminals respectively facing the primary electrode and the secondary electrode are arranged in the case in which the piezoelectric body is accommodated. These terminals are used for electrical connection with the piezoelectric body (primary electrode, secondary electrode) outside the case.

  A primary conductive rubber layer, an insulating rubber layer, and an elastic holding member are disposed between the primary electrode and the terminal facing the primary electrode. Of these, the conductive rubber layer is placed between each primary electrode of the piezoelectric body and the terminal facing it in the case, and both the primary electrode and the terminal are in contact with each other to conduct electricity to each other. It is something to be made. In addition, the insulating rubber layer is press-fitted between the primary electrodes of the piezoelectric body and the terminals facing the piezoelectric body in the case in a state of being superimposed on the conductive rubber layer. The conductive rubber layer is held in contact with both of them. The elastic holding member is disposed by being press-fitted between each primary electrode of the piezoelectric body and the terminal facing the piezoelectric body in the case together with the conductive rubber layer and the insulating rubber layer, and is in contact with at least the primary electrode And holding both the conductive rubber layer and the insulating rubber layer.

  According to said structure, the laminated | stacked part of an electroconductive rubber layer and an insulating rubber layer respond | corresponds to the part which contacts a terminal, The electrical conduction with a primary electrode and a terminal is achieved by the electroconductive rubber layer. Further, by adopting the laminated structure, the proportion of the conductive rubber layer in the whole can be suppressed, and the amount of the conductive material used can be suppressed correspondingly. On the other hand, since the elastic holding member is provided separately from the laminated portion of the conductive rubber layer and the insulating rubber layer, it is possible to sufficiently secure the overall mechanical strength combining them.

  A secondary-side conductive rubber layer and an insulating rubber layer are disposed between the secondary electrode and the terminal facing the secondary electrode. Of these, the conductive rubber layer is disposed in the case by being press-fitted between the secondary electrode of the piezoelectric body and the terminal opposite to the piezoelectric electrode. It is made to conduct. In addition, the insulating rubber layer is disposed so as to be press-fitted between the secondary electrode of the piezoelectric body and the terminal facing the piezoelectric material in the case in a state of being superimposed on the conductive rubber layer on the secondary side. The conductive rubber layer is held in contact with both the secondary electrode and the terminal.

  Since the portion of the piezoelectric body on which the secondary electrode is formed has a larger amplitude than the portion of the primary electrode, the conductive rubber layer itself may have a mechanical strength higher than that of the primary conductive rubber layer. desirable. When a metal (for example, silver) having a lower electric resistance is used as the conductive material for the conductive rubber layer on the primary side, the nonconductive metal layer that can ensure mechanical strength than the secondary conductive rubber layer. It is preferable to use a material (for example, carbon). In this case, on the secondary side, even if only two types of conductive rubber layer and insulating rubber layer are used, sufficient mechanical strength can be exhibited while achieving necessary conductivity.

  For example, when the secondary electrode is formed only on one side of the two outer surfaces that form a pair in the thickness direction among the outer surfaces of the piezoelectric body, an elastic member is provided between the outer surface opposite to the secondary electrode and the inner surface of the case. Can be arranged. One surface of the piezoelectric body is supported by an elastic member, and the other surface is supported by a secondary conductive rubber layer and an insulating rubber layer, so that the piezoelectric body is sandwiched between them. Accordingly, the piezoelectric body can be supported in a balanced manner in the case, and it is possible to prevent the biased force from being applied to the piezoelectric body.

  According to the present invention, a stable operation is realized by absorbing mechanical vibration generated in the piezoelectric body while achieving necessary electrical conduction between the electrode and the terminal of the piezoelectric body by an elastic member having conductivity. can do. Furthermore, by arranging an elastic member different from the conductive elastic member together, the overall mechanical strength can be increased, and a highly reliable piezoelectric transformer that can sufficiently withstand long-term use can be obtained.

  Further, by suppressing the amount of the conductive material used in a product unit as a piezoelectric transformer, the manufacturing cost can be greatly reduced while achieving necessary conductivity.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a perspective view showing a piezoelectric transformer 100 according to an embodiment in an exploded manner. FIG. 2 is a horizontal sectional view (II-II section in FIG. 1) showing the piezoelectric transformer 100 in a completed state. As shown in FIG. 1, the piezoelectric transformer 100 mainly includes a piezoelectric ceramic 102 and a resin case 104, and the piezoelectric ceramic 102 is accommodated in the resin case 104. 1 is the bottom surface side of the resin case 104, and the piezoelectric transformer 100 is mounted as a whole with the bottom surface of the resin case 104 facing the mounting surface of a circuit board (not shown). The

  The piezoelectric ceramic 2 is obtained by polarizing a piezoelectric body such as lead zirconate titanate ceramic (PZT). Although the shape of the piezoelectric ceramic 102 is not particularly limited, a rectangular parallelepiped shape (flat plate shape) can be given as an example here.

  A primary electrode 106 is formed on each of the outer surfaces of the piezoelectric ceramic 102 that are paired in the thickness direction. Although only one side is shown in FIG. 1, a similar primary electrode 106 is formed on the opposite side. Further, on the outer surface of the piezoelectric ceramic 102, a secondary electrode 108 is formed at the other end in the longitudinal direction on one surface (one surface shown in the figure) that is paired in the thickness direction. The primary electrode 106 and the secondary electrode 108 are formed on the outer surface of the piezoelectric ceramic 102 by, for example, screen printing using a metal paste.

  A housing portion 104 a is formed inside the resin case 104, and the housing portion 104 a is open on the bottom surface side of the resin case 104. Although not shown in FIG. 1, the opening of the resin case 104 is only on the bottom surface side, and the upper surface (located below in FIG. 1) is closed. In the accommodating part 104a, the piezoelectric ceramics 102 can be accommodated in a vertically placed posture (a state in which the side end surface around the waist is set upside down). A side wall 104 b is formed around the accommodating portion 104 a, and the side wall 104 b is slightly higher than the length of the piezoelectric ceramic 102 in the vertical direction.

  The resin case 104 is provided with recesses 104c, 104d, 104e, and 104f at four locations in the accommodating portion 104a. All of these four concave portions 104c to 104f are formed so as to scoop (depress) the side wall 104b from the inside of the accommodating portion 104a toward the outside with a certain width. Of these, the two concave portions 104c and 104d are in a positional relationship facing each other with the piezoelectric ceramic 102 interposed therebetween in the accommodating portion 104a, and the concave portions 104c and 104d have the same (symmetric) shape. The other recesses 104e and 104f are also in a positional relationship facing each other with the piezoelectric ceramic 102 interposed therebetween, but the other recess 104f is smaller than the one recess 104e.

  The resin case 104 is provided with a total of three terminals 110, 112, and 114. Among these, the two terminals 110 and 112 are disposed in the resin case 104 so as to face the primary electrode 106 of the piezoelectric ceramic 102. Further, the remaining terminals 114 are arranged in the resin case 104 so as to face the secondary electrode 108 of the piezoelectric ceramic 102. The resin case 104 is formed with insertion grooves 104g that penetrate a top plate (not shown) and extend in the vertical direction in the side wall 104b. The three terminals 110, 112, and 114 are respectively inserted into the corresponding insertion grooves 104g. It is installed in the resin case 104 in a state where Since the inner method of each insertion groove 104g is set to be slightly smaller than the thickness of the terminals 110, 112, 114, each terminal 110, 112, 114 is fixed in an interference fit state in the insertion groove 104g.

  The insertion groove 104g communicates with the recesses 104c, 104d, and 104e in the accommodating portion 104a. That is, when viewed from the inside of the accommodating portion 104a, the insertion groove 104g is formed so as to scoop (depress) the side wall 104b further outward in a groove shape on the inner surface of each recess 104c, 104d, 104e. Therefore, the side surfaces of the terminals 110, 112, and 114 are exposed in the recesses 104c, 104d, and 104e in a state where the terminals 110, 112, and 114 are inserted into the insertion grooves 104g.

  In the state in which the piezoelectric ceramic 102 is accommodated in the accommodating portion 104a, the conductor block 116 is installed in each of the two recesses 104c and 104d that make a pair, and another conductor block 120 is disposed in the other recess 104e. Is installed. A block-like silicone rubber 122 is installed in the remaining recess 104f. The piezoelectric ceramic 102 is held in the resin case 104 in a state of being sandwiched between the two conductor blocks 116 and between the conductor block 120 and the silicone rubber 122.

  As shown in FIG. 2, the piezoelectric ceramic 102 is bonded to the resin case 104 using, for example, a silicone adhesive 124. A protruding rib 104h for guiding the piezoelectric ceramic 102 from both sides is formed in the housing portion 104a, and the silicone adhesive 124 is filled in the resin case 104 so as to cover the rib 104h.

  The conductor blocks 116 and 120 have a rubber material having conductivity, and in addition to the elasticity of silicone rubber as a base material, the conductor blocks 116 and 120 also have conductivity by a conductive material kneaded therein. . In the resin case 104, the primary electrode 106 and the secondary electrode 108 of the piezoelectric ceramic 102 and the terminals 110, 112, and 114 are electrically connected through conductor blocks 116 and 120, respectively. Hereinafter, the conductor blocks 116 and 120 will be described in detail.

  FIG. 3 is an enlarged view of a portion around the primary-side conductor block 116 shown in FIG. The two conductor blocks 116 are respectively disposed between the primary electrode 106 of the piezoelectric ceramic 102 and the terminals 110 and 112 in the resin case 104. At this time, the conductor block 116 is fitted into the corresponding recesses 104c and 104d, and is compressed (press-fitted) between the primary electrode 106 and the terminals 110 and 112.

  The conductor block 116 is roughly composed of, for example, a conductive member 116a and an elastic holding member 116b. As seen in the horizontal cross section shown in FIG. 3, the conductor block 116 has a structure in which a conductive member 116a is used as an intermediate layer, and holding layers of elastic holding members 116b are laminated on both sides thereof. Here, the direction of lamination is a direction along the outer surface of the piezoelectric ceramic 102 (longitudinal direction).

  At the positions of both end faces in the longitudinal direction of the conductor block 116 (vertical direction in FIG. 3), the end faces of the conductive member 116a are in close contact with the primary electrode 106 and the terminals 110 and 112, respectively. On both sides, the end face of the elastic holding member 116b is in close contact with the primary electrode 106 and the inner surfaces of the recesses 104c and 104d. Since the conductor block 116 is in a compressed state as a whole as described above, both end surfaces of the conductive member 116a and the primary electrode 106 or the terminals 110 and 112 are strongly pressed by the repulsive force. Therefore, the electrical contact resistance between the conductive member 116a and the primary electrode 106 or between the conductive member 116a and the terminals 110 and 112 is reduced.

  Next, FIG. 4 is an enlarged view of a portion around the secondary side conductor block 120 and the silicone rubber 122 shown in FIG. Among these, the conductor block 120 is disposed between the secondary electrode 108 and the terminal 114 of the piezoelectric ceramic 102 in the resin case 104. The silicone rubber 122 is disposed between the outer surface of the piezoelectric ceramic 102 opposite to the secondary electrode 108 and the side wall 104b. At this time, the conductor block 120 is fitted in the recess 104e and is compressed (press-fitted) between the secondary electrode 108 and the terminal 114. The silicone rubber 122 is also fitted in the recess 104f and is compressed (pressed) between the outer surface of the piezoelectric ceramic 102 and the side wall 104b.

  The conductor block 120 is simply composed of two layers, a conductive rubber layer 120a and a silicone rubber layer 120b. The conductive rubber layer 120a and the silicone rubber layer 120b have a structure in which the resin case 104 is alternately stacked in the depth direction (longitudinal direction of the terminal 114). In the horizontal cross section shown in FIG. 4, only the cross section of either the conductive rubber layer 120a or the silicone rubber layer 120b is shown, and the laminated structure is not shown because of the cross-sectional direction. These laminated structures will be further described later with reference to another drawing.

  At the positions of both end faces of the conductor block 120 in the longitudinal direction (vertical direction in FIG. 4), the end faces of the conductive rubber layer 120a and the silicone rubber layer 120b are in close contact with the secondary electrode 108 and the terminal 114, respectively. is there. Since the conductor block 120 is also in a compressed state as a whole, both end faces of the conductive rubber layer 120a and the secondary electrode 108 or the terminal 114 are strongly pressed by the repulsive force. Therefore, the electrical contact resistance between the conductive rubber layer 120a and the secondary electrode 108 or between the conductive rubber layer 120a and the terminal 114 is also reduced here.

[Primary side]
FIG. 5 is a diagram showing the primary-side conductor block 116 alone. 5A is a perspective view of the conductor block 116, and FIG. 5B is a longitudinal sectional view (BB cross section) thereof.

  As described above, the conductor block 116 has a laminated structure in which the conductive layer of the conductive member 116a is sandwiched at the center and the holding layers of the elastic holding member 116b are formed on both sides thereof. In the present embodiment, the conductive member 116a itself has a multilayer structure (zebra structure). Here, the conductive rubber layer 116c and the insulating silicone rubber layer 116d are stacked in the vertical direction. .

[Primary side conductive rubber layer (first elastic member), primary side insulating rubber layer (second elastic member)]
Of these, the conductive rubber layer 116c is made of, for example, silicone rubber as a base material and kneaded with silver (Ag) therein to provide conductivity and elasticity. The silicone rubber layer 116d is simply made of silicone rubber, and does not exhibit electrical conductivity among the conductive members 116a. Such a silicone rubber layer 116d holds the conductive rubber layer 116c in the stack of the conductive members 116a and contributes to improving the overall mechanical strength.

  As described above, the conductive rubber layer 116c and the silicone rubber layer 116d have a laminated structure in which they overlap each other when viewed in the longitudinal direction of the corresponding terminals 110 and 112, respectively. In addition, the width W of the conductive member 116a is slightly larger than the width of the outer surface of the terminals 110 and 112 exposed in the recesses 104c and 104d. In this case, each conductive rubber layer 116c intersects (substantially orthogonal) with each other in the longitudinal direction of the terminals 110 and 112, so that the end surfaces of all the conductive rubber layers 116c in the conductive member 116a are the terminal 110 , 112 can be brought into contact with each other, and the electrical resistance as a whole can be reduced accordingly.

[Elastic holding member (second elastic member)]
The elastic holding members 116b located on both sides of the conductive member 116a are also made of, for example, simple silicone rubber. Such an elastic holding member 116b holds the conductive member 116a from both sides in the conductor block 116, thereby improving the mechanical strength of the conductor block 116 as a whole. Further, since the elastic holding members 116b are arranged on both sides of the conductive member 116a, the conductor block 116 has an outer shape (size, volume) that is easy to handle as a whole.

〔Secondary side〕
Next, FIG. 6 is a view showing the secondary-side conductor block 120 alone. 6A is a perspective view of the conductor block 120, and FIG. 6B is a longitudinal sectional view (BB cross section) thereof.

[Secondary conductive rubber layer (first elastic member), Secondary insulating rubber layer (second elastic member)]
As described above, the conductor block 120 has a laminated structure (zebra structure) in which the conductive layer of the conductive rubber layer 120a and the holding layer of the silicone rubber layer 120b are alternately stacked.

  Of these, the conductive rubber layer 120a is made by, for example, using silicone rubber as a base material, and kneading carbon fine particles therein to impart conductivity and elasticity. Further, the silicone rubber layer 120 b is simply made of, for example, silicone rubber, and does not exhibit electrical conductivity in the conductor block 120. Such a silicone rubber layer 120b contributes to holding the conductive rubber layer 120a in the stack of the conductor blocks 120 and improving the overall mechanical strength.

  As described above, the conductive rubber layer 120a and the silicone rubber layer 120b have a laminated structure in which they are alternately overlapped when viewed in the longitudinal direction of the corresponding terminal 114. Further, the width W of the entire conductor block 120 is sufficiently larger than the width of the outer surface of the terminal 114 exposed in the recess 104e. In this case, each of the conductive rubber layers 120a intersects (substantially orthogonal) with each other in the longitudinal direction of the terminals 114, so that the end surfaces of all the conductive rubber layers 120a in the conductor block 120 are connected to the terminals 114. The overall electrical resistance can be reduced by that amount. The conductor block 120 corresponding to the secondary electrode 108 has an outer shape (size, volume) that is easy to handle as it is because the width W of the conductive rubber layer 120a is equal to the entire width.

[Elastic member]
As described above, since the secondary electrode 108 is formed only on one surface of the piezoelectric ceramic 102, only one conductor block 120 is required. However, since the conductor block 120 is compressed between the secondary electrode 108 and the terminal 114, considering the balance in the resin case 104, the conductor block 120 is opposite to the secondary electrode 108 as in the present embodiment. Silicone rubber 122 is also preferably disposed on the surface. Such a silicone rubber 122 sandwiches the piezoelectric ceramics 102 from both sides together with the conductor block 120 in the resin case 104, and contributes to absorbing mechanical vibration generated during the operation.

  This completes the description of the structure of the piezoelectric transformer 100 of the present embodiment. In such a piezoelectric transformer 100, the terminals 110, 112, and 114 are connected to the wiring pattern in a state of being mounted on the circuit board as described above. When an input voltage is applied to the primary electrode 106 through the terminals 110 and 112, the primary-side conductor block 116 performs electrical conduction and absorbs mechanical vibration generated in the piezoelectric ceramic 102. . In addition, when the output voltage transformed by the mechanical vibration of the piezoelectric ceramic 102 is taken out from the secondary electrode 108 through the terminal 114, the secondary-side conductor block 120 conducts electrically and is generated in the piezoelectric ceramic 102. It plays a role in absorbing mechanical vibrations.

The piezoelectric transformer 100 of the present embodiment described above exhibits superiority from the following viewpoints, for example.
(1) Since separate conductor blocks 116 and 120 are used for the primary side and the secondary side, and the conductive rubber layer 116c using a metal (silver) as a conductive material is adopted for the primary side, piezoelectric The electric resistance when applying an input voltage to the ceramics 102 can be further reduced.

(2) Since each of the conductor blocks 116 and 120 on the primary side and the secondary side has a structure (zebra structure) in which the conductive rubber layers 116c and 120a and the silicone rubber layers 116d and 120b are laminated, The amount of the conductive material (silver, carbon) that occupies the volume of can be reduced.

(3) Further, on the primary side, since the entire conductor block 116 has a multilayer structure of the conductive member 116a and the elastic holding member 116b, the conductive material (particularly silver) occupies the entire volume compared to the secondary side. The amount used can be reduced.

  The position where the primary-side conductor block 116 is in contact corresponds to a vibration node (position of amplitude 0) viewed in the longitudinal direction of the piezoelectric ceramic 102. For this reason, extremely large friction (shear stress) does not occur at the contact surface between the primary electrode 106 and the conductor block 116. Strictly speaking, however, the vibration node is only on a virtual straight line (a straight line perpendicular to the longitudinal direction of the piezoelectric ceramic 102), and if it deviates slightly in the longitudinal direction from this straight line, the amplitude increases accordingly. Will go. Therefore, if the conductive member 116a is arranged at the center of the vibration node and the silicone rubber elastic holding members 116b are arranged on both sides as in the present embodiment, the vibration generated at a position off the node. Can be satisfactorily absorbed, and the conductive member 116a having a relatively low strength can be brought into contact with the node, whereby the overall durability can be improved.

  However, when the primary side (primary electrode 106) of the piezoelectric ceramic 102 is fixed at the vibration node in the resin case 104, the fixing member may not have elasticity. In this case, at least the fixing member on the secondary side (secondary electrode 108) may be an elastic member (conductor block 120) having conductivity, and the conductive member having no elasticity instead of the conductor block 116 on the primary side. These fixing members may be interposed, or the distance between the terminals 110 and 112 on both sides may be narrowed to contact the primary electrode 106.

  In the present embodiment, for the secondary side conductor block 120 having a larger amplitude than the primary side, the conductive rubber layer 120a is composed of silicone rubber containing carbon fine particles, and this is formed by a simple silicone rubber layer 120b. Since the retained structure is employed, sufficient mechanical strength can be ensured while providing overall conductivity.

[Another embodiment]
FIG. 7 is a diagram independently showing a conductor block 216 different from the embodiment (second example). The conductor block 216 can be used in place of, for example, the primary-side conductor block 116 described in the embodiment. 7A is a perspective view of the conductor block 216, and FIG. 7B is a longitudinal sectional view (BB cross section). In addition, in the figure, the same code | symbol is attached | subjected about the matter which is common with one Embodiment, and the duplicate description shall be abbreviate | omitted.

  The conductor block 216 of the second example has a structure in which the conductive layer of the conductive member 116a is sandwiched in the center, and the holding layers of the elastic holding member 116b are formed on both sides and top and bottom, respectively. In the second example, since the elastic holding members 116b are arranged on the upper and lower sides in addition to the both sides, the overall size of the conductive member 116a is reduced accordingly. Therefore, it is possible to further reduce the amount of the conductive material used as a whole while obtaining the necessary conductivity as the conductive member 116a. In the second example, the elastic holding member 116b holds the conductive member 116a from the periphery, thereby further improving the mechanical strength of the conductor block 116 as a whole.

  In addition, as long as an electrical connection relationship between the conductive member 116a and the terminals 110 and 112 is obtained, a structure in which the elastic holding member 116b is disposed only on one side of the conductive member 116a can be employed. .

  The present invention can be implemented with various modifications without being limited to the above-described embodiments. In the embodiment, separate conductor blocks 116 and 120 are used on the primary side and the secondary side, but both may be common, or the conductor blocks 116 and 120 may be shared on the primary side and the secondary side. 120 may be replaced.

  Further, the number of conductive rubber layers 116c and 120a stacked in each of the conductor blocks 116 and 120 is not particularly limited, and the conductive rubber layers 116c and 120a can be provided if necessary conductivity (electric resistance) is obtained. The number of stacked layers and the layer thickness can be changed as appropriate.

  In addition, the shapes and structures of the members and parts described in the embodiments are merely preferred examples, and it goes without saying that the present invention can be implemented by appropriately modifying them.

It is the perspective view which decomposed | disassembled and showed the piezoelectric transformer of one Embodiment to the component. It is a horizontal sectional view (II-II section in Drawing 1) which shows a piezoelectric transformer in a completed state. FIG. 3 is an enlarged view of a portion around a primary-side conductor block in FIG. 2. FIG. 3 is an enlarged view of a portion around a secondary side conductor block and silicone rubber in FIG. 2. It is a figure which shows the conductor block of a primary side independently. It is a figure which shows the electric conductor block of a secondary side independently. It is a figure which shows the conductor block of a 2nd example independently.

Explanation of symbols

100 Piezoelectric Transformer 102 Piezoelectric Ceramics (Piezoelectric Body)
104 Resin case 106 Primary electrode 108 Secondary electrode 110, 112, 114 Terminal 116, 120 Conductor block 116a Conductive member 116b Elastic holding member 116c Conductive rubber layer 116d Silicone rubber layer 120a Conductive rubber layer 120b Silicone rubber layer 122 Silicone Rubber

Claims (3)

A piezoelectric body in which a primary electrode is formed on each of two outer surfaces that are paired with each other, and a secondary electrode is formed on the outer surface at a position different from these primary electrodes,
A case for housing the piezoelectric body;
A plurality of terminals arranged to face the primary electrode and the secondary electrode of the piezoelectric body in a state where the piezoelectric body is accommodated in the case, and to conduct with the piezoelectric body outside the case;
In the case, the piezoelectric body is press-fitted between each primary electrode of the piezoelectric body and the terminal facing the piezoelectric body, and has electrical conductivity to contact both the primary electrode and the terminal and to make them mutually conductive. Primary side conductive rubber layer,
In the state of being overlaid on the primary-side conductive rubber layer, the case is press-fitted between each primary electrode of the piezoelectric body and the terminal facing the piezoelectric body in the case, and both the primary electrode and the terminal A primary-side insulating rubber layer that holds the conductive rubber layer in contact with
The primary side conductive rubber layer and the primary side insulating rubber layer are disposed in the case so as to be press-fitted between each primary electrode of the piezoelectric body and the terminal facing the primary electrode, and at least contact the primary electrode. A piezoelectric transformer, comprising: an elastic holding member that holds both the primary side conductive rubber layer and the primary side insulating rubber layer in a state of being formed. The piezoelectric transformer according to claim 1 ,
In the case, the piezoelectric electrode is placed between the secondary electrode of the piezoelectric body and the terminal facing the piezoelectric body, and has electrical conductivity that makes contact with both the secondary electrode and the terminal so that they are electrically connected to each other. A secondary conductive rubber layer,
The secondary electrode and the terminal are disposed by being press-fitted between the secondary electrode of the piezoelectric body and the terminal facing the piezoelectric body in the case in a state of being superimposed on the secondary conductive rubber layer. And a secondary insulating rubber layer that holds the secondary conductive rubber layer in contact with both of the piezoelectric transformers. The piezoelectric transformer according to claim 2 ,
Of the outer surface of the piezoelectric body, it is disposed between the outer surface opposite to the secondary electrode and the inner surface of the case, and at this position, the secondary conductive rubber layer and the secondary side insulation A piezoelectric transformer, further comprising an elastic member that supports the piezoelectric body in the case together with a conductive rubber layer.

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