CN1217427C - Bending Vibration Mode Piezoelectric Step-Up Transformer - Google Patents

Abstract

The piezoelectric ceramic booster transformer and the preparation method utilize a mechanical series connection structure of an input end and an output end to enable the piezoelectric ceramic to generate resonance, and output boosting at the output end, and obtain high electric power conversion efficiency. The piezoelectric transformer is prepared by adopting an integrated co-firing process, and has the characteristics of compact structure, small device size, stable working performance and the like. It is suitable for miniaturized electronic instruments. The main advantages of the device are: the device is shaped as a flat cuboid structure. A co-firing process and a size optimization technology are adopted, and a bending oscillation mode which is less adopted in the general situation is introduced into the design of the step-up transformer. And a multilayer co-firing structure is adopted, so that the regulation range of the input voltage is widened.

Description

Bending Vibration Mode Piezoelectric Step-Up Transformer

technical field

The invention relates to solid-state electronic components, in particular to a piezoelectric ceramic step-up transformer.

Background technique

It is known that in the application field of electronic ceramic power devices, the technology of using piezoelectric ceramics to convert voltage or current through the forward and reverse piezoelectric effect, specifically, this technology is to carry out certain polarization orientation and The electrode design uses the inverse piezoelectric effect to make piezoelectric ceramics produce mechanical oscillations under the excitation of the input voltage, and then uses the positive piezoelectric effect to convert the mechanical vibration energy into electrical energy at the output end, so as to realize the mechanical energy as the medium in the power transmission process. Power exchange. In the energy conversion process, the structure and size of the piezoelectric ceramic transformer, the vibration mode and the electric energy extraction mode affect the input and output electrical impedance characteristics of the piezoelectric ceramic transformer itself. When the electrical impedance of the input and output terminals is not equal, the voltage between the input and output terminals will not be equal under the condition of load matching, which is equivalent to the electromagnetic transformer in effect, which is usually called a piezoelectric ceramic transformer.

Piezoelectric ceramic transformers can be divided into two types from the function of step-up and step-down. The former is mainly aimed at high output voltage, while the latter is mainly aimed at step-down and high output power. They have become electronic ceramic components that have attracted special attention in recent years. The reason is that compared with the electromagnetic transformers that are widely used at present, they are non-flammable, no electromagnetic radiation, small in size, and simple in structure. They are suitable for the rapid development in recent years. Miniaturization of electronic communications, computer equipment, etc. In the early 1990s, major Japanese companies and research institutions, such as NEC, Toshiba, Tokin and the University of Tokyo, targeted computer equipment and carried out research on the application of piezoelectric ceramic transformers. After nearly ten years of research work, it is the first to realize large-scale applications in the field of portable computer LCD screen displays and computer step-down transformers. Therefore, it can be expected that piezoelectric ceramic transformers will play an important role in future electronic components.

Figure 1 shows the piezoelectric ceramic step-up transformer structure first proposed by Rosen in 1956. This kind of transformer uses the piezoelectric gauge d ₃₁ of piezoelectric ceramics to generate transverse vibration, and then uses the piezoelectric gauge d ₃₃ to obtain a longitudinal electric field parallel to the vibration direction to obtain high output voltage. In this structure, the input and output A large difference in terminal resistance can ensure a high output voltage for the load, so the transformer generally adopts an asymmetric structure. At present, most piezoelectric ceramic step-up transformers are developed based on the Rosen type structure, and the ones used for portable computer liquid crystal display screens are based on Rosen's improved multilayer ceramic transformer. Japanese Patent Application No. 09059969 is an example of this type of piezoelectric transformer.

Figure 2 shows the basic structure of a multilayer piezoelectric ceramic step-up transformer. The piezoelectric transformer adopts thickness mode oscillation, firstly it utilizes the piezoelectric strain coefficient d ₃₃ of the piezoelectric ceramic to generate thickness direction vibration, and then uses the piezoelectric strain coefficient d ₃₃ to obtain a longitudinal electric field parallel to the vibration direction to obtain high output voltage . According to the difference of input and output impedance, a higher output voltage is obtained. The input and output current of this structure transformer is larger than other types of step-up transformers, and the step-up transformation ratio is between 1 and 30, so it can meet the growing miniaturization and high transformation ratio AC-AC (AC-AC) and DC-DC (DC-DC) conversion circuit application requirements. NEC Corporation of Japan adopted the input and output structures of multilayer ceramic sheets similar to those shown in Figure 2, and prepared a 15-fold longitudinal thickness vibration mode step-up transformer. US Patent No. 8313971 is an example of such a piezoelectric ceramic transformer.

For the above-mentioned piezoelectric transformer, the piezoelectric ceramics at the input and output ends adopt a mutual-coupled working principle. And the part of the piezoelectric ceramic connected to the input end is driven by the voltage to make the piezoelectric ceramic device produce an overall mechanical movement, and the mechanical energy is transferred to another piezoelectric ceramic as the output end through standing wave vibration to obtain electrical energy. The thickness vibration mode multilayer piezoelectric transformer shown in Figure 2 generally works in a relatively high vibration frequency range due to its structural characteristics, so the aging phenomenon of the device is serious. At the same time, the polarization steps in the manufacturing process of the multilayer piezoelectric transformer with this structure are also relatively complicated. (J.W. Wanders, Piezoelectric Ceramics: properties and applications, Philips, 1991). In addition, in the traditional process, the adhesive bonding method is used to bond the ceramic sheets prepared by the dry pressing method into a multi-layer integrated structure. Although the cost is low and the process is simple, due to the mechanical resistance of the adhesive and the piezoelectric ceramic If they are not matched, the electrical power conversion efficiency of the device will be greatly reduced. In view of the deficiencies in the above traditional device design and manufacturing process, exploring new device design structures and optimizing the manufacturing process method are of great practical value for the production of miniaturized electronic devices suitable for different working environment conditions.

Contents of the invention

An object of the present invention is to provide a structural design of a multilayer piezoelectric transformer in bending vibration mode.

Another object of the present invention is to provide a process for preparing a multilayer piezoelectric transformer in bending vibration mode.

The multilayer piezoelectric transformer in bending vibration mode provided by the present invention includes:

The two-part voltage input terminals located on both sides of the transformer are symmetrically distributed relative to the output terminals. The input end is composed of two layers of piezoelectric ceramics and a platinum metal internal electrode co-fired structure. The output end is a single-layer piezoelectric ceramic structure. The input end and output end are integrated co-firing structure. External electrodes are arranged on the outer surfaces of the input end and the output end. The external electrodes are respectively located on the upper and lower surfaces and the left and right sides of the transformer. The external electrodes of the ground wire lead-out end of the input end are located on the left and right sides of the transformer in the length direction, and are connected to the co-fired internal electrodes between the two layers of piezoelectric ceramics at the input end. The outer electrodes of the live wire lead-out end of the input end and the outer electrodes of the output end are respectively located on the upper and lower surfaces of the transformer, and are evenly coated along the length direction of the transformer surface according to the relationship of 1/3 of the surface length of the transformer. The external electrodes are connected to the lead wires of the input and output ends. It is characterized in that the piezoelectric transformer input ends located on the left and right sides of the transformer have the same polarization direction of the two layers of piezoelectric ceramics, which are both perpendicular to the plane where the inner and outer electrodes are located, and the directions of the input voltages that excite the two layers of piezoelectric ceramics are opposite, so that produce bending mode oscillations. The polarization direction of the output end is parallel to the input end, and according to the positive piezoelectric effect of piezoelectric ceramics, the mechanical energy of bending oscillation is converted into electrical energy for output.

Another feature of the transformer is that it is a flat cuboid structure as a whole. The working effect of the device can be obviously improved through the size optimization technology. The length, width and height of the optimized device are 32:8:1.5. Two parts of input terminals and a part of output terminals are evenly distributed along the length direction of the transformer, each occupying 1/3 of the radial size of the length. The input end is located on both sides of the output end, and the input end contains two layers of piezoelectric ceramics and the inner electrode. The output end is located in the middle of the transformer, and the output end is a single-layer piezoelectric ceramic structure.

Another feature of the transformer of the present invention is that the thickness of the two layers of piezoelectric ceramics at the input end is equal, and the metal inner electrode is located between the two layers of piezoelectric ceramics. The input end is a multi-layer-integrated co-fired structure.

Another aspect of the transformer of the present invention is characterized in that: the transformer is excited in a d ₃₁ manner and generates standing wave oscillation along the length direction, and the bending mode motion is generated through the combined effect of the multilayer structure in different oscillation directions, and then the bending mode is adopted. Mode positive piezoelectric effect to achieve boost output. Vibration modes include low-order and high-order vibration modes.

Another aspect of the transformer of the present invention is characterized in that: the input end includes at least two layers of piezoelectric ceramic structures, and the piezoelectric ceramic sheets are electrically connected in parallel and mechanically connected in series, thereby further increasing the voltage between the output and the input voltage. Proportion.

Another aspect of the transformer of the present invention is characterized in that: the two piezoelectric ceramic sheets are ceramic sheets of different thicknesses made by rolling film method or casting method.

Another aspect of the transformer of the present invention is characterized in that: the integrated structure of the ceramic blank and the metal inner electrode is realized by a hot pressing process and a pressure sintering method.

Another aspect of the transformer of the present invention is characterized in that: the piezoelectric ceramic sheet at the input and output ends is an integrated sintered structure, including a co-fired structure of a ceramic blank at the input end and a platinum inner electrode, and is integrated with the ceramic sheet Sintered silver outer electrodes.

The preparation method of the piezoelectric step-up transformer of the multilayer co-fired structure bending vibration mode of the present invention is as follows:

1). Prepare a piezoelectric ceramic fresh film material with a thickness of 200 microns by rolling film method or casting method.

2). The internal electrode of the input end is coated by screen printing method, and the coating area of the internal electrode is equal to the area of the input end, and is also distributed on the left and right sides of the transformer length direction.

3). The integrated structure of the ceramic green body and the platinum metal internal electrode is realized by using the hot pressing process and pressure sintering.

4).Using the high temperature co-firing process to coat the silver external electrode on the surface of the transformer. The lead-out ends of the ground wires of the external electrodes at the input end are connected to the metal internal electrodes, which are respectively located on the left and right sides of the transformer.

5). Then weld wires in the middle of all the external electrodes at the input end and output end respectively as the external working connection of the transformer.

6). Polarize the input and output terminals of the transformer by using the step-by-step polarization method.

The bending vibration mode piezoelectric ceramic step-up transformer with multi-layer integrated co-fired structure provided by the present invention is characterized in that the transformer has simple structure, convenient preparation, small device thickness, low operating frequency range, aging resistance, and can effectively improve output voltage, and has high electrical power conversion efficiency.

1. From the perspective of the preparation process, the present invention adopts film rolling or casting method to prepare fresh ceramic film material, and adopts hot pressing process and integrated sintering method to prepare multilayer structure piezoelectric step-up transformer. The structure is simple and the technological means are mature.

2. From the perspective of the device structure, since there are two parts of the input end to provide excitation oscillation, the working mode of the device can obtain stable standing wave oscillation in both low-order and high-order. At the same time reduce parasitic vibration and reduce energy consumption.

3. From the perspective of the vibration generation of the device and the conversion of mechanical energy to electricity, due to the use of the piezoelectric system d ₃₁ transverse length stretching mode, through the multi-layer combined motion effect, bending oscillations are generated in the length direction, so a lower operating frequency can be obtained. At the same time, the co-firing method and the bending oscillation mode are used to obtain high mechanical energy and electrical energy conversion efficiency of the device even when the thickness of the device is very thin.

4. From the perspective of device size, since the device adopts a flat cuboid structure, the actual occupied space is small, and it is easy to assemble in an integrated circuit system as a small voltage regulation device. At the same time, the size optimization technology is adopted, and the device has a good working effect.

5. From the perspective of the excitation method of the piezoelectric transformer, the combination of the longitudinal oscillation effects generated by the multi-layer structure at the input end generates the overall bending oscillation mode of the device, and then the positive piezoelectric effect of the bending oscillation mode at the output end Convert mechanical energy into electrical energy and obtain higher voltage output. This is also the key point of the structure of the present invention: it enables the piezoelectric ceramic step-up transformer to have the above advantages, and makes the design and manufacture of the step-up transformer more flexible.

Description of drawings

The features and advantages of the structure of the present invention will be further clarified below with specific examples with reference to the accompanying drawings.

Figure 1 is a structural schematic diagram of a Rosen-type piezoelectric ceramic step-up transformer.

Fig. 2 is a schematic structural diagram of a multilayer piezoelectric ceramic step-up transformer.

Fig. 3 is a structural schematic diagram of a piezoelectric ceramic step-up transformer in a bending vibration mode with a multi-layer integrated co-fired structure according to the present invention.

Fig. 4 is a schematic longitudinal cross-sectional view of a piezoelectric ceramic step-up transformer in bending vibration mode with a multi-layer integrated co-fired structure of the present invention.

5 is a cross-sectional view of the left and right output ends of the bending vibration mode piezoelectric ceramic step-up transformer of the multi-layer integrated co-fired structure of the present invention, and the arrows in the figure indicate the polarization direction of the piezoelectric ceramic.

Fig. 6(a) is a schematic diagram of the third-order bending oscillation deformation mode of the bending vibration mode piezoelectric ceramic step-up transformer of the multi-layer integrated co-fired structure of the present invention.

Fig. 6(b) is a schematic diagram of the third-order bending oscillation stress distribution of the bending vibration mode piezoelectric ceramic step-up transformer of the multi-layer integrated co-fired structure of the present invention.

Fig. 7 is a schematic diagram of an equivalent circuit of longitudinal vibration of the bending vibration mode electric ceramic step-up transformer of the multi-layer integrated co-fired structure of the present invention.

Fig. 8 is the bending vibration mode piezoelectric ceramic step-up transformer of multi-layer integrated co-fired structure of the present invention under the condition of constant load resistance (1187 ohms) and constant input voltage (effective value 0.7 volts), its input and output voltage Schematic diagram of the curve of boost ratio versus operating frequency.

Fig. 9 is the bending vibration mode piezoelectric ceramic step-up transformer of multi-layer integrated co-fired structure of the present invention under the conditions of constant load resistance (1187 ohms) and constant input voltage (effective value 0.7 volts), its output electric power varies with the working Schematic diagram of the curve of frequency change.

Fig. 10 shows the bending vibration mode piezoelectric ceramic step-up transformer with multilayer integrated co-fired structure of the present invention under the conditions of constant load resistance (1187 ohms) and constant input voltage (effective value 0.7 volts), its electric power transmission efficiency varies with Schematic diagram of the curve of the operating frequency change.

Fig. 11 is the curve of the step-up ratio of the input and output voltage changing with the load resistance under the condition of constant operating frequency (approximately 205K Hz) of the bending vibration mode piezoelectric ceramic step-up transformer with multi-layer integrated co-fired structure of the present invention schematic diagram.

Detailed ways

Referring to Fig. 3, what the present invention provides is the bending vibration mode piezoelectric ceramic step-up transformer of the multi-layer integrated co-fired structure of the present invention, which includes: two input end ceramics and metal The internal electrode co-fired structure, the single-layer piezoelectric ceramic structure at the output end located in the middle of the transformer length direction. The input end and output end are integrated co-firing structure. The inner electrode of the input end adopts a high temperature resistant sintered platinum electrode. External electrodes are arranged on the outer surfaces of the input end and the output end. The external electrodes are respectively located on the upper and lower surfaces and the left and right sides of the transformer. The external electrodes of the ground wire lead-out end of the input end are located on the left and right sides of the transformer in the length direction, and are connected to the co-fired internal electrodes between the two layers of piezoelectric ceramics at the input end. The outer electrodes of the live wire lead-out end of the input end and the outer electrodes of the output end are respectively located on the upper and lower surfaces of the transformer, and are evenly coated along the length direction of the transformer surface according to a 1/3 length relationship. The external electrodes are connected to the lead wires of the input and output ends. It is characterized in that the piezoelectric transformer input terminals located on the left and right sides of the transformer have the same polarization direction of the two layers of piezoelectric ceramics, both of which are perpendicular to the plane where the inner and outer electrodes are located, and the voltage at the input terminals of the excitation two layers of piezoelectric ceramics passes through the leads of the outer electrodes They are respectively applied to two layers of polarized piezoelectric ceramic sheets. Due to the connection method of the lead wires, the voltage directions on the two layers of piezoelectric ceramic sheets at the input end are just opposite, resulting in a stretching motion in the length direction opposite to the vibration direction. The length direction of the two aspects The synthetic effect of the stretching motion, that constitutes the bending mode oscillations. The polarization direction of the output end is parallel to the input end, and according to the positive piezoelectric effect of piezoelectric ceramics, the mechanical energy of bending oscillation is converted into electrical energy for output.

The piezoelectric step-up transformer of the present invention is a flat cuboid, and the ratio of its length, width, and thickness after size optimization is roughly 32:8:1.5.

The piezoelectric step-up transformer of the present invention is excited by the vibration mode in the d ₃₁ transverse length direction, and realizes boost output by the bending oscillation mode, and the vibration modes include low-order and high-order vibration modes.

The input end of the piezoelectric step-up transformer of the present invention has a multi-layer structure, two piezoelectric ceramics at the input end are electrically connected in parallel, and the ceramic sheets at the input and output ends are mechanically connected in series.

In the present invention, fresh abrasive materials for piezoelectric ceramics are prepared by extrusion film method or tape casting method, and then their integrated structure is realized by hot pressing and pressure sintering methods, and the surface silver external electrodes are prepared by high temperature co-firing process.

In the present invention, the input ends of the piezoelectric transformer located on the left and right sides of the transformer have the same polarization direction of the two layers of piezoelectric ceramics, both of which are perpendicular to the plane where the inner and outer electrodes are located, and are excited in the transverse d ₃₁ vibration mode. The input terminal voltages for exciting the two layers of piezoelectric ceramics are respectively applied to the two layers of polarized piezoelectric ceramics. The polarization direction is shown as P in Figure 3 or 4, and the direction is just opposite, so that the longitudinal direction of the vibration direction is opposite. The motion, the composite effect of both lengthwise stretching motions, constitutes bending mode oscillations. The polarization direction of the output end is parallel to the input end, and according to the positive piezoelectric effect of piezoelectric ceramics, the mechanical energy of bending oscillation is converted into electrical energy for output.

The preparation method of the piezoelectric step-up transformer of the multilayer co-fired structure bending vibration mode of the present invention comprises:

1). Prepare a piezoelectric ceramic fresh membrane material with a thickness of 200 microns by squeezing the membrane method or casting method. According to the design requirements, the membrane material is cut according to a certain size.

2). The inner electrode of the input terminal is coated by screen printing and dried at 80 degrees Celsius.

3). The integrated structure of the ceramic green body and the platinum metal internal electrode is realized by using the hot pressing process and pressure sintering.

4).Using the high temperature co-firing process to coat the silver external electrode on the surface of the transformer. Wherein, the lead-out end of the external electrode ground wire of the input terminal is connected to the metal internal electrode, which are respectively located on the left and right sides of the transformer. The coating position of the external electrode is shown in the dark gray shaded part in Figure 3.

5). Then weld wires in the middle of all the external electrodes at the input end and output end respectively as the external working connection of the transformer.

6).Use the stepwise polarization method to polarize the input and output ends of the transformer.

Example:

The hard-doped PZT-based piezoelectric ceramic material is used as the basic material of the structure of the present invention to prepare a fresh ceramic membrane material. After printing the platinum inner electrode, the transformer rough blank is prepared by hot pressing process and pressure sintering method, and then coated with silver electrode. The silver electrodes are sintered at high temperature, the wires are welded at the position of minimum strain, and the input and output terminals of the transformer are polarized step by step. The final product is obtained: a multilayer integrated co-fired structure piezoelectric ceramic step-up transformer with bending vibration mode, and its dimensions are as follows:

Length L = 32 mm,

Thickness H = 1.5 mm,

Width W = 8mm.

For the PZT materials used in the above examples, the properties of the prepared single-layer piezoelectric ceramics are as follows: piezoelectric coupling coefficient d ₃₃ =320, mechanical quality factor Q _m =960, dielectric coefficient ε ₃₃ (1KHz)=1300 .

Fig. 6 shows the equivalent circuit of piezoelectric vibration at the input and output ends of the bending vibration mode piezoelectric ceramic step-up transformer of the multi-layer integrated co-fired structure of the present invention. The circuit is measured and the result is:

Input: resonant frequency = 204.8 kHz, anti-resonant frequency = 221.18 kHz,

Piezoelectric coupling coefficient d ₃₃ = 160, equivalent internal resistance = 2.54 ohms,

Equivalent inductance = 0.79 microhenry, equivalent capacitance C _a = 850 picofarads

Equivalent capacitance C _b = 4970 picofarads, mechanical quality factor Q _m = 436.13

Output: resonant frequency = 196.1 kHz, anti-resonant frequency = 209.7 kHz,

Piezoelectric coupling coefficient d ₃₃ = 300, equivalent internal resistance = 16.3 ohms,

Equivalent inductance = 7.2 microhenries, equivalent capacitance C _a = 89.9 picofarads

Equivalent capacitance C _b = 667 picofarads, mechanical quality factor Q _m = 587.5

From the above measurement results, it can be seen that the co-firing method and the introduction of the inner electrode have a certain impact on the overall performance of the piezoelectric device, such as the piezoelectric coupling coefficient and the mechanical quality factor have decreased to a certain extent, but due to the small decrease , so it will not hinder the performance of the device in actual work.

Fig. 8 shows the variation of the input-output voltage ratio with the operating frequency under the condition that the measured input effective voltage is 0.7 volts and the load resistance is 1187 ohms. It can be seen from the figure that at 197.3 kHz, close to the resonance frequency, the input-to-output voltage ratio has the highest value, reaching 5.7.

Fig. 9 shows the variation of the output electric power value with the operating frequency under the condition that the measured input effective voltage is 0.7 volts and the load resistance is 1187 ohms. It can be seen from Fig. 9 that at 197 kHz, close to the resonant frequency, the output electric power has the highest value, reaching 31.5 microwatts.

Fig. 10 shows the variation of power transmission efficiency with operating frequency under the condition that the measured input effective voltage is 0.7 volts and the load resistance is 1187 ohms. It can be seen from the figure that at 205 kHz, close to the anti-resonance frequency, the energy transmission efficiency has the highest value, reaching 80.17%.

Figure 11 shows that in the measurement, when the input operating frequency is roughly constant, the ratio of the effective value of the input voltage to the output voltage changes with the load resistance. It can be seen from the figure that the higher the load resistance is, the higher the step-up ratio of the input and output voltage becomes. When the load resistance reaches 4 megaohms, the step-up ratio basically reaches a stable maximum value of about 9. During the performance measurement of the above piezoelectric ceramic transformer, the temperature of the piezoelectric ceramic transformer did not change.

Claims (7)

1. the piezoelectricity step-up transformer of a multilayer co-firing structure, beam mode, comprising: be positioned at two parts voltage input end of transformer both sides, it distributes with respect to the output left-right symmetric; Input is made of electrode co-sintering structure in two-layer piezoelectric ceramic and the platinum; Output is an individual layer piezoelectric ceramic structure, the integrated co-sintering structure of input and output; The outer surface of input and output is provided with external electrode, external electrode lays respectively at the upper and lower surface and the left and right sides of transformer, wherein the external electrode of input ground wire exit is positioned at the length direction left and right sides of transformer, and it is connected in the interior electrode of common burning between the two-layer piezoelectric ceramic of input; Input live wire exit external electrode and output external electrode lay respectively at the transformer upper and lower surface, and evenly are coated with along the relation of transformer length surface direction according to 1/3 transformer length surface, and external electrode connects the lead-in wire of input and output; It is characterized in that, be positioned at the piezoelectric transformer input of the transformer left and right sides, its two-layer piezoelectric ceramic polarised direction unanimity, all perpendicular to plane, internal and external electrode place, encourage the input terminal voltage direction of two-layer piezoelectric ceramic opposite, thereby produce the beam mode vibration, the output polarised direction is parallel with input, according to the direct piezoelectric effect of piezoelectric ceramic, the mechanical energy that bending is vibrated is converted to the output of electric energy form.

2. according to the transformer of claim 1, it is characterized in that: transformer integral body is a flat rectangular structure, long, wide, scaling relation is on the Senior Three direction: long: wide: height is 32: 8: 1.5, and two parts input and a part of output are evenly distributed along the transformer length direction, respectively accounts for 1/3 length radial dimension, input is positioned at the output both sides, and output is positioned in the middle of the transformer.

3. according to the transformer of claim 2, it is characterized in that: input is for containing the integrated co-sintering structure of metal inner electrode multilayer.

4. according to the transformer of claim 1, it is characterized in that described transformer is with d ₃₁Mode encourages and the direct piezoelectric effect by crooked oscillation mode produces the output of boosting, and mode of oscillation comprises the mode of oscillation of low order and high-order.

5. according to the transformer of claim 1, it is characterized in that: input comprises two-layer piezoelectric ceramic structure at least, and described two-layer piezoelectric ceramic is in parallel on electricity, connects on mechanical structure, thereby further improves the ratio between output and the input voltage.

6. according to transformer any in the claim 1 to 5, it is characterized in that: the integrated sintering structure of described input/output terminal piezoelectric ceramic devices, the co-sintering structure that comprises the plain embryo of input pottery and the interior electrode of platinum, and with the silver-colored external electrode of described two-layer ceramic integral sintering.

7. according to the transformer of claim 1, it is characterized in that: piezoelectric ceramic is in the longitudinal direction with horizontal d ₃₁The vibration mode excitation, the positive piezoelectricity benefit of crooked oscillation mode is boosted, thereby realizes the conversion between electric energy-mechanical energy-electric energy, and its vibration mode comprises low order and high frequent vibration mode.

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