JP2007150131A - Piezoelectric transformer - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an excellent-in-reliability piezoelectric transformer in which, even if it is set up such that its longer direction is perpendicular to the direction of gravitation force, the fixed part of the piezoelectric transformer's element and case will not have a temporal influence by the gravity, generating no unpleasant sound due to contact of the piezoelectric transformer element and the case's inner wall. <P>SOLUTION: The transformer is structured such that it is fixed by an adhesive and the like through an elastic component 9 such as an elastic binder, etc. to the bottom of a case 3 composed of a frame body having a bottom at two sides that form a thickness of a rectangular plate-shaped piezoelectric transformer element 2. Further, the case 3 is mounted onto a component mounting surface 33 such that the longer direction side surface of the case 3 perpendicularly touches at the component mounting surface 33. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a piezoelectric transformer, and more particularly to a piezoelectric transformer element casing and a substrate mounting structure suitable for a backlight lighting boosting module for lighting a cold cathode tube for a backlight of a liquid crystal display panel.

  In recent years, cold cathode fluorescent lamps have been used as backlights for liquid crystal display panels such as portable personal computers. In order to light up the cold cathode tube, a backlight lighting boosting module (hereinafter referred to as an inverter) for generating a high voltage and applying the high voltage to the cold cathode tube is required. For this inverter, a piezoelectric transformer having features such as downsizing, power saving, and low noise is used.

  Various types of piezoelectric transformer elements have been proposed for piezoelectric transformers. FIG. 1 is a perspective view of a piezoelectric transformer. For example, the piezoelectric transformer element 51 uses a rectangular plate-shaped piezoelectric ceramic plate, has input electrodes 52 on both sides from the center in the longitudinal direction, and has an input portion polarized in the thickness direction indicated by an arrow 54, An output electrode 53 is provided on the end surface 57 in the longitudinal direction on the side where the input electrode 52 is not provided, and an output portion polarized in the length direction indicated by an arrow 55 between the input electrode 52 and the output electrode 53 is provided. A Rosen-type piezoelectric transformer element is known as a general structure. The piezoelectric transformer element 51 applies an input voltage via a lead wire (not shown) attached to the input electrode 52 to mechanically vibrate the piezoelectric ceramic plate, and applies a high voltage generated at the output portion to the output electrode 53. The lead wire (not shown) is taken out.

  In addition, since a high voltage of several kV is generated at the output portion of the piezoelectric transformer element 51, the piezoelectric transformer element 51 needs to be isolated from the surroundings and ensure a creepage distance for safety reasons. Generally, it is housed in a resin case in consideration of attachment to the substrate.

  However, since the piezoelectric transformer element 51 converts mechanical vibration into electrical output by the piezoelectric effect, when the piezoelectric transformer element 51 is housed in a case, the vibration is impaired and the performance is impaired. Therefore, a non-vibrating portion of the piezoelectric transformer element 51, that is, a so-called node portion is bonded and bonded to the case with an elastic adhesive or the like. At this time, in consideration of workability of applying an elastic adhesive, securing a bonding area, and the like, it is common to use a surface having a large surface area of the piezoelectric transformer element 51 as a bonding surface.

  In addition, a general storage structure of the piezoelectric transformer element 51 may be such that a sufficient clearance is secured between the outer shape of the piezoelectric transformer element 51 and the case inner wall so that the piezoelectric transformer element 51 does not contact the inner wall of the case. It is. The contact between the piezoelectric transformer element 51 and the inner wall of the case not only impedes the vibration of the piezoelectric transformer element 51 and deteriorates the performance, but also causes a phenomenon of “sounding” that generates unpleasant noise.

  Various studies have been made on the method for housing the piezoelectric transformer element 51 in the case, including the method for eliminating the above-mentioned “sounding”.

  For example, FIG. 2 is a structural diagram of a conventional piezoelectric transformer. 2A is a perspective view, FIG. 2B is a top view, FIG. 2C is a DD ′ cross-sectional view of FIG. 2B, and FIG. 2D is an EE ′ cross-section of FIG. 2C. FIG. FIG. 2A is a perspective view showing a state in which the conventional piezoelectric transformer 18 is mounted on the mounting surface of the substrate 28. The structure of the conventional piezoelectric transformer 18 includes a piezoelectric transformer element 19 and a case 20 that houses the piezoelectric transformer element 19. Although the piezoelectric transformer element 19 is shown in a transmission diagram, input electrodes 22 are provided on the upper and lower surfaces of the piezoelectric transformer element 19. An output electrode 24 is provided at the longitudinal end of the piezoelectric transformer element 19.

  The case 20 that houses the piezoelectric transformer element 19 is provided with two input terminals 26 and an output terminal 27, and the lead wire 23 soldered to the input electrode 22 of the piezoelectric transformer element 19 is connected to the input terminal 26. A lead wire 25 connected and soldered to the output electrode 24 is connected to the output terminal 27.

  FIG. 2B is a top view of the piezoelectric transformer 18 as viewed from directly above. Further, FIG. 2C shows a cross section of the straight line DD ′ shown in the figure. As shown in FIG. 2C, the piezoelectric transformer element 19 is joined to the bottom surface of the case 20 via an elastic member 21 such as an elastic adhesive at two portions serving as vibration nodes. The piezoelectric transformer 18 is mounted on the substrate 28 in this state.

  FIG. 2D shows a cross section of the straight line EE ′ shown in FIG. As shown in FIG. 2D, the piezoelectric transformer 18 is mounted such that the surface of the piezoelectric transformer element 19 having a large surface area is parallel to the component mounting surface 34 of the substrate 28.

  In the piezoelectric transformer, a “sound” is prevented by forming a gap between the piezoelectric transformer element and the case. Such a piezoelectric transformer is disclosed in Patent Document 1.

JP 2003-133606 A

  FIG. 3 is an explanatory diagram of a conventional backlight unit. 3A is a perspective view, FIG. 3B is a plan view, and FIG. 3C is an FF ′ cross-sectional view of FIG. 3B.

  As shown in FIG. 3A, an inverter 29 for turning on a liquid crystal display panel backlight of a personal computer and a thin TV equipped with the piezoelectric transformer 18 is used to realize the thinning required for the personal computer and the thin TV. In addition, the component mounting surface 34 of the board is arranged so as to be parallel to the backlight unit 30.

  Further, as shown in FIG. 3B, the cold cathode tubes 31 arranged in the backlight unit 30 are arranged so that the longitudinal direction is orthogonal to the direction of gravity indicated by the arrow 35. Therefore, the arrow 36 indicating the direction of the current flowing through the cold cathode tube 31 is also perpendicular to the arrow 35 which is the direction of gravity. This is to prevent the gas sealed in the cold cathode tube 31 from being affected by gravity and being biased toward the direction of gravity over time and causing problems such as uneven brightness.

  Therefore, in accordance with the arrow 36 indicating the direction of the current flowing through the cold cathode tubes 31 arranged in the backlight unit 30 as described above, the direction of the current flowing from the input to the output of the inverter 29 is also the arrow 35 indicating the direction of gravity. Accordingly, the piezoelectric transformer is arranged so that the longitudinal direction is perpendicular to the arrow 35 which is the direction of gravity.

  FIG. 3C is a cross-sectional view showing the F-F ′ cross section of the I portion shown in FIG. When the above-described conventional piezoelectric transformer is used, the piezoelectric transformer 18 is mounted such that the longitudinal direction of the piezoelectric transformer 18 is parallel to the component mounting surface 34 of the substrate 28 as shown in FIG. Therefore, the piezoelectric transformer element 19 is arranged such that the short side direction is parallel to the direction of gravity.

  Therefore, the elastic member 21 that joins the piezoelectric transformer element 19 and the case 20 receives a shearing stress due to the weight of the piezoelectric transformer element 19. There is a problem that the piezoelectric transformer element 19 moves in the direction of gravity indicated by an arrow 35 over time due to the influence of the shear stress.

  Since the piezoelectric transformer element 19 contains lead oxide, has a large specific gravity of around 8 and is a heavy component, the elastic member 21 is significantly affected by the mass of the piezoelectric transformer element 19. This time-dependent movement of the piezoelectric transformer element 19 in the direction of gravity indicated by the arrow 35 eliminates the clearance from the inner wall of the case 20 that is housed, and the piezoelectric transformer element 19 and the inner wall of the case 20 come into contact with each other, thereby inhibiting vibration. There is a problem that performance degradation or “sounding” occurs due to the sound.

  In order to solve this problem, it is a shortcut to select a high-hardness adhesive that is not easily affected by gravity over time for joining the piezoelectric transformer element 19 and the case 20. Such an adhesive hinders mechanical vibration of the piezoelectric transformer element 19, so that the characteristic deterioration is large, and is not suitable as a bonding material for the piezoelectric transformer element 19 and the case 20.

  Furthermore, if the positional change of the piezoelectric transformer element 19 over time is predicted to provide a large clearance between the piezoelectric transformer element 19 and the inner wall of the case 20 in advance, the above problem can be solved, but this clearance is required as an inverter product. Since the piezoelectric transformer element 19 can be equal to the distance that the piezoelectric transformer element 19 moves due to an impact during a mechanical test such as a drop test, if the clearance is large, the lead wire joined to the electrode with solder or the like is disconnected, causing a problem. Is more likely to occur. Furthermore, providing a large clearance also increases the external dimensions of the case 20, which makes it difficult to reduce the size of the inverter product.

  Therefore, an object of the present invention is to solve the above-mentioned problems of the prior art. Specifically, when the component mounting surface of the inverter board is also arranged perpendicular to the horizontal plane in accordance with the backlight unit arranged perpendicular to the horizontal plane, the piezoelectric element is arranged on the inverter board mounting surface. The fixed part of the transformer's piezoelectric transformer element and the case inner wall is not affected by gravity over time, the position of the piezoelectric transformer element is not easily changed, and the clearance according to the design concept can be maintained. The contact between the piezoelectric transformer element and the case inner wall It is an object of the present invention to provide a highly reliable piezoelectric transformer that does not generate “sounding” due to the above, has little deterioration in characteristics, and has high reliability.

  The present invention employs the following means in order to solve the above problems. That is, according to the present invention, the surface that forms the thickness of the piezoelectric transformer element is perpendicular to the direction of gravity when the piezoelectric transformer is mounted on a substrate or the like and is actually used. Thus, the gist is to constitute the case in which the piezoelectric transformer element is arranged.

  According to the present invention, there is provided a piezoelectric transformer comprising a rectangular plate-shaped piezoelectric transformer element and a bottomed frame body capable of accommodating the piezoelectric transformer element, wherein the piezoelectric transformer element has two thicknesses. One side is fixed to the bottom of the frame via an elastic member, and has an input terminal and an output terminal that can be mounted by bringing one of the side surfaces in the longitudinal direction of the frame into contact with the mounting substrate surface. Is obtained.

  The piezoelectric transformer according to the present invention has an elastic member such as an elastic adhesive on the bottom of a case in which one of the two surfaces forming the thickness of the rectangular plate-shaped piezoelectric transformer element, that is, one having a large surface area is a bottomed frame. It is structured to be fixed by bonding or the like via Further, it is assumed that the case is mounted on a substrate or the like. At this time, the piezoelectric transformer is mounted by bringing one side of the longitudinal side surfaces of the frame body, that is, two side surfaces in the longitudinal direction of the case, into contact with the mounting substrate surface with respect to the substrate mounting surface. A positional relationship is formed such that the two surfaces forming the thickness of the element are perpendicular to the mounting substrate surface. In other words, a positional relationship is configured such that the width direction of the piezoelectric transformer element is perpendicular to the mounting substrate surface.

  The case includes an input terminal for inputting an input voltage to an input electrode of the piezoelectric transformer element, and an output terminal for outputting an output voltage obtained by boosting the input voltage. The piezoelectric transformer according to the present invention can be mounted by bonding the input terminal and the output terminal to a wiring pattern on the mounting substrate surface.

  Further, according to the present invention, the bottomed frame body has the two surfaces forming the thickness of the piezoelectric transformer element perpendicular to the gravity direction or not parallel to the gravity direction. A piezoelectric transformer is obtained in which the piezoelectric transformer element is fixed so that the element is mounted on the mounting substrate surface.

  When a substrate such as an inverter on which the piezoelectric transformer of the present invention is mounted is arranged in parallel with a crystal display backlight unit such as a personal computer or a thin TV, for example, the piezoelectric transformer element and the inner wall of the case are joined. Since the elastic member such as the elastic adhesive receives the mass of the piezoelectric transformer element vertically, it does not receive a shearing force, and the position change of the piezoelectric transformer element with time due to the influence of gravity is reduced.

  Accordingly, it is possible to maintain a clearance according to the design concept in which the piezoelectric transformer element and the inner wall of the case do not contact each other. In addition, since the surface having the large surface area of the piezoelectric transformer element is mounted in a relationship perpendicular to the mounting surface of the mounting substrate, the mounting area can be greatly reduced.

  According to the present invention, the piezoelectric transformer element is characterized in that a no-vibration node is fixed to the bottom of the frame.

  In the piezoelectric transformer according to the present invention, the piezoelectric transformer element does not vibrate when the piezoelectric transformer element is fixed to the bottom portion of the case made of the bottomed frame body by bonding or the like via an elastic member such as an elastic adhesive. By fixing the node portion, a highly efficient piezoelectric transformer can be obtained without inhibiting the vibration of the piezoelectric transformer element.

  As described above, according to the present invention, when the component mounting surface of the inverter board is disposed in parallel with the backlight unit, the piezoelectric transformer element of the piezoelectric transformer disposed on the mounting surface of the inverter board and The part fixed to the inner wall of the case is not affected by gravity over time, the position of the piezoelectric transformer element is difficult to change, the clearance according to the design concept can be maintained, and `` sounding '' due to the contact between the piezoelectric transformer element and the inner wall of the case It is possible to provide a piezoelectric transformer that does not occur, has little deterioration in characteristics, and has excellent reliability.

  The piezoelectric transformer according to the present invention includes a rectangular plate-shaped piezoelectric transformer element made of a piezoelectric material such as piezoelectric ceramics, and a bottomed frame that serves as a case for housing the piezoelectric transformer element. The piezoelectric transformer element need only be in the shape of a rectangular plate, and an input electrode is provided from the longitudinal center to the end of both surfaces of the two surfaces forming the thickness, polarization is performed in the thickness direction, and an output electrode is provided on the other end surface. In addition to the so-called Rosen-type piezoelectric transformer provided and polarized in the longitudinal direction between the input electrode and the output electrode, any type of piezoelectric transformer such as a symmetrical third-order Rosen type can be used in the present invention.

  The case is formed of a frame having a bottom, and the shape of the bottom is approximately the same shape, which is several mm larger than the two surfaces forming the thickness of the piezoelectric transformer element. The piezoelectric transformer element is housed so that two surfaces forming the thickness of the piezoelectric transformer element are parallel to the bottom surface of the case. At this time, an elastic member such as an elastic adhesive is interposed between the bottom of the case and the piezoelectric transformer element, and the piezoelectric transformer element is fixed to the bottom of the case. Accordingly, it is preferable that the height of the case be several mm higher than the thickness of the elastic member and the thickness of the piezoelectric transformer element.

  An input terminal and an output terminal are provided on either one of the two side surfaces including the longitudinal direction of the frame of the case. The input electrode and the output electrode of the piezoelectric transformer element are connected to the input terminal and the output terminal by lead wires or the like, respectively. In addition, when the piezoelectric transformer according to the present invention is mounted on a substrate or the like, the input terminal and the output terminal are in contact with the substrate mounting surface and connected to the wiring pattern on the substrate, and the piezoelectric transformer according to the present invention is fixed to the substrate. Make it possible.

  Hereinafter, the piezoelectric transformer of the present invention will be described in more detail with specific examples.

  FIG. 4 is a structural diagram of the piezoelectric transformer of this embodiment. 4 (a) is a perspective view, FIG. 4 (b) is a top view seen from the direction G shown in FIG. 4 (a), FIG. 4 (c) is an AA ′ sectional view of FIG. 4 (b), and FIG. (D) is BB 'sectional drawing of FIG.4 (b). FIG. 4A is a perspective view showing the piezoelectric transformer 1 of this embodiment mounted on the substrate 10. A piezoelectric transformer 1 according to this embodiment includes a piezoelectric transformer element 2 and a case 3.

  The piezoelectric transformer element 2 used in this example was a rectangular plate-shaped piezoelectric ceramic having a length of 42 mm, a width of 8 mm, and a thickness of 2.5 mm. The piezoelectric transformer element 2 is provided with an input electrode 4 on the two surfaces having a length of 42 mm and a width of 8 mm from the center in the longitudinal direction to the end, polarized in the thickness direction, and having a width of 8 mm and a thickness at the other end. This is a Rosen-type piezoelectric transformer element in which an output electrode 7 is provided on an end face of 2.5 mm and polarization is performed in the longitudinal direction between the input electrode 4 and the output electrode 7.

  The case 3 that houses the piezoelectric transformer element 2 includes a bottom 41 and a frame 42. The piezoelectric transformer element 2 was accommodated so that a surface having a length of 42 mm and a width of 8 mm was in contact with the surface of the bottom 41 via an elastic member 9 as shown in FIG. The frame 42 has inner dimensions of 51 mm in length, 14 mm in width, and 5 mm in height so that clearance can be created around the piezoelectric transformer element 2 when the piezoelectric transformer element 2 is housed.

  Also, the input terminal 11 and the output terminal 12 are provided on one of the two side surfaces of the case 3 in the longitudinal direction, and the frame on the side where the input terminal 11 and the output terminal 12 are provided. The side surface of 42 is brought into contact with the substrate 10, and the input terminal 11 and the output terminal 12 are soldered to the substrate 10, whereby the piezoelectric transformer 1 according to the present embodiment is fixed on the substrate 10 and the input terminal. 11 and the output terminal 12 are connected to a wiring pattern on the substrate 10. The wiring pattern is not shown. The input electrode 4 provided on the piezoelectric transformer element 2 is connected to the input terminal 11 through a lead wire 5, and the output electrode 7 is connected to the output terminal 12 through a lead wire 8.

  FIG. 4B shows a top view of the piezoelectric transformer 1 of the present embodiment as seen from the direction of the arrow G shown in FIG. Further, the A-A ′ cross section shown in FIG. 4B is shown in FIG. 4C, and the B-B ′ cross section is shown in FIG. As shown in FIG. 4C, in this embodiment, the piezoelectric transformer element 2 is fixed to the bottom 41 of the case 3 through an elastic member 9 made of a silicone-based adhesive. At this time, the place where the piezoelectric transformer element 2 is fixed is a portion which becomes a vibration node of the piezoelectric transformer element 2.

  In the present embodiment, as described above, when the piezoelectric transformer 1 is mounted on the substrate 10, the width direction of the piezoelectric transformer element 2 is relative to the component mounting surface 33 of the substrate 10 as shown in FIG. A vertically arranged structure was adopted. The case 3 was made of a liquid crystal polymer resin, and the input terminal 11 and the output terminal 12 were produced by injection molding by insert molding.

  FIG. 5 is an explanatory diagram of the backlight unit according to the present embodiment. 5 (a) is a perspective view, FIG. 5 (b) is a plan view, and FIG. 5 (c) is a CC ′ cross-sectional view of FIG. 5 (b). FIG. 5A is a perspective view of a backlight unit of a liquid crystal display panel for a thin TV actually manufactured using the piezoelectric transformer according to the present embodiment. A backlight inverter 13 having 16 piezoelectric transformers 1 according to this embodiment mounted on the component mounting surface 33 of the substrate 10 is disposed in the backlight unit 14.

  As shown in FIG. 5 (b), 16 cold cathode tubes 15 are arranged in the backlight unit 14, and the piezoelectric transformer 1 and the cold cathode tubes 15 are connected via the output connector 17 on the substrate 10. In addition, power can be supplied to the inverter 13 through the input connector 16.

  Usually, the backlight unit 14 is disposed on the back surface of a liquid crystal display panel such as a thin TV. Accordingly, in the backlight unit 14, as shown in FIG. 5A, the surface 43 of the backlight unit 14 is perpendicular to the horizontal plane formed by the coordinates XY shown in FIG. 5A. Will be used in the state.

  FIG. 5C shows a C-C ′ cross-sectional view of the H portion shown in FIG. As shown in FIG. 5 (c), in the actual use state, the piezoelectric transformer element 2 of the piezoelectric transformer 1 of the present embodiment is such that the width direction of the piezoelectric transformer element 2 is perpendicular to the component mounting surface 33 of the substrate 10. Therefore, the elastic member 9 that joins the piezoelectric transformer element 2 to the bottom 41 of the case 3 receives the mass of the piezoelectric transformer element 2 in the direction of the arrow 35 that is the direction of gravity, that is, in the vertical direction. Therefore, the structure is such that the position of the piezoelectric transformer element 2 is not changed over time due to the influence of gravity without receiving shearing force.

  In the embodiment, a silicone-based adhesive having elasticity after curing is used as the elastic member 9, which also serves as fixing of the piezoelectric transformer element 2, but through rubber, sponge or pre-cured silicone, The piezoelectric transformer element 2 may be bonded and fixed to the bottom 41 of the case 3 with an adhesive.

  Further, in this embodiment, the piezoelectric transformer 1 was designed and implemented assuming that the backlight unit 14, the inverter 13, and the substrate 10 thereof are arranged perpendicular to the horizontal plane and parallel to the direction of gravity. However, in consideration of a state in which the backlight unit 14 is actually used, it may be assumed that the backlight unit 14 is used at a certain angle in addition to being perpendicular to the horizontal plane. In this case, the surface forming the thickness of the piezoelectric transformer element 2 by giving an angle corresponding to the angle to the surface of the case 3 mounted on the substrate 10 or using a hinge mechanism or the like, What is necessary is just to design the structure of case 3 suitably so that it may always be arrange | positioned perpendicular | vertical with respect to the gravitational direction. Further, it may be arranged so as to be in a substantially vertical state even if it is not completely perpendicular to the direction of gravity.

  Further, in this embodiment, the surface in the longitudinal direction of the case 3 is used as the mounting surface with the substrate 10 in order to reduce the height dimension from the substrate 10 when the piezoelectric transformer 1 is mounted on the substrate 10. In the case where it is more important to reduce the mounting area of the 13 substrates 10, the surface in the width direction may be used as the mounting surface. In this embodiment, the case 3 has a bottomed frame to increase the insulation. However, if there is no problem with insulation, the case 3 is composed only of the bottom and the mounting surface without using a frame. It is also good.

  As described above, according to the present invention, the fixing portion between the piezoelectric transformer element and the case of the piezoelectric transformer is not affected by the time due to gravity, and the clearance according to the design concept is achieved without causing the position of the piezoelectric transformer element to change. It is possible to provide a piezoelectric transformer that can be maintained, does not generate unpleasant noise due to contact between the piezoelectric transformer element and the inner wall of the case, has little deterioration in characteristics, and has excellent reliability.

  The piezoelectric transformer according to the present invention can be used not only for a backlight inverter of a liquid crystal display panel such as a portable personal computer or a liquid crystal television, but also for a booster circuit in various electronic devices.

The perspective view of a piezoelectric transformer. 2 (a) is a perspective view, FIG. 2 (b) is a top view, FIG. 2 (c) is a sectional view taken along DD 'in FIG. 2 (b), and FIG. 2 (d) is a diagram. EE 'sectional drawing of 2 (c). FIG. 3A is a perspective view, FIG. 3B is a plan view, and FIG. 3C is an FF ′ cross-sectional view of FIG. 3B. FIG. 4 (a) is a perspective view, FIG. 4 (b) is a top view seen from the G direction, FIG. 4 (c) is an AA ′ sectional view of FIG. 4 (b), and FIG. 4 (d) is a BB ′ sectional view of FIG. 4 (b). FIG. 5A is a perspective view, FIG. 5B is a plan view, and FIG. 5C is a CC ′ cross-sectional view of FIG. 5B.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1,18 Piezoelectric transformer 2,19,51 Piezoelectric transformer element 3 Case 4,22,52 Input electrode 5,8,23,25 Lead wire 7,24,53 Output electrode 9,21 Elastic member 10,28 Board | substrate 11,26 Input terminal 12, 27 Output terminal 13, 29 Inverter 14, 30 Backlight unit 15, 31 Cold cathode tube 16 Input connector 17 Output connector 20 Case 33, 34 Component mounting surface 35, 36, 54, 55 Arrow 41 Bottom 42 Frame 43 surface 57 end face

Claims (3)

  A piezoelectric transformer comprising a rectangular plate-shaped piezoelectric transformer element and a bottomed frame that can accommodate the piezoelectric transformer element, wherein one side of the two surfaces forming the thickness of the piezoelectric transformer element is the frame body. A piezoelectric transformer comprising an input terminal and an output terminal which are fixed to a bottom portion via an elastic member and which can be mounted by bringing a side surface of the frame into contact with a mounting substrate surface in the same surface of the side surface. .   The bottomed frame body is configured such that the piezoelectric transformer element is mounted on the mounting substrate surface in a state where two surfaces forming the thickness of the piezoelectric transformer element are perpendicular to the direction of gravity. The piezoelectric transformer according to claim 1, wherein the piezoelectric transformer is fixed.   3. The piezoelectric transformer according to claim 1, wherein the piezoelectric transformer element fixes a node portion that does not vibrate to a bottom portion of the frame body. 4.

Images