A flip-chip piezoelectric stack

Abstract

The application discloses a flange electrode type piezoelectric stack, which comprises at least one second piezoelectric sheet, the second piezoelectric sheet comprising a second substrate, a third electrode and a fourth electrode, the second substrate being provided with a second through hole penetrating through the thickness of the second substrate, the second substrate having a third surface and a fourth surface opposite in the axial direction, and a second outer ring surface located on the radial outside and a second inner ring surface located on the radial inside, the third electrode being arranged on the third surface and extending to the fourth surface through the second outer ring surface or the second inner ring surface, the fourth electrode being arranged on the fourth surface and extending to the second outer ring surface or the second inner ring surface, and the third electrode and the fourth electrode being insulated from each other; when stacked, the at least one second piezoelectric sheet is configured to be connected with corresponding electrodes of a first piezoelectric sheet, and / or a plurality of second piezoelectric sheets are connected in sequence. Through the design of the flange electrode, the arrangement of the electrode in the three-dimensional space is realized, and stable and reliable electrical connection can be realized without complex internal connecting wires or external jumpers.

Description

Technical Field

[0001] This application relates to the field of piezoelectric stack technology, and in particular discloses a flipped electrode type piezoelectric stack. Background Technology

[0002] Piezoelectric stacks are key actuation components that can convert electrical energy into mechanical energy. Their basic principle is to utilize the inverse piezoelectric effect generated by multiple piezoelectric ceramic sheets under the action of an electric field. They are stacked in parallel through electrical connection, thereby obtaining a large cumulative displacement or output force under relatively low voltage drive. Therefore, their performance directly determines the output capability of the entire system. Piezoelectric stacks are widely used in precision positioning, vibration control, microelectromechanical systems, and active vibration reduction. In these applications, the core requirements for piezoelectric stacks are always higher output force and more compact structure.

[0003] However, traditional piezoelectric stacks typically employ a planar electrode structure, where electrodes are only arranged on the upper and lower surfaces of the piezoelectric element. This structure often requires the introduction of complex internal wiring or external circuitry for multi-layer stacking and electrical interconnection, which not only increases the difficulty and cost of manufacturing but may also lead to reduced overall reliability of the stack, internal stress concentration, and problems such as response hysteresis or signal crosstalk under high-frequency dynamic conditions. Furthermore, the planar electrode design limits the flexibility of electrode lead-out, restricting the stack in terms of structural compactness, diverse connection methods, and configuration of different polarization directions. Therefore, improvements are needed. Utility Model Content

[0004] The purpose of this application is to provide a piezoelectric stack with a flanged electrode.

[0005] To achieve the above objectives, the technical solution adopted in this application is as follows: a flanged electrode type piezoelectric stack, comprising at least one second piezoelectric sheet, the second piezoelectric sheet comprising a second substrate, a third electrode and a fourth electrode, the second substrate having a second through hole penetrating its thickness, the second substrate having a third surface and a fourth surface opposite to each other along the axial direction, and a second outer ring surface located radially outward and a second inner ring surface located radially inward, the third electrode being disposed on the third surface and extending to the fourth surface through the second outer ring surface or the second inner ring surface, the fourth electrode being disposed on the fourth surface and extending to the second outer ring surface or the second inner ring surface, the third electrode and the fourth electrode being mutually insulated; when stacked, at least one second piezoelectric sheet is configured to be connected to the corresponding electrode of the first piezoelectric sheet, and / or several second piezoelectric sheets are connected sequentially.

[0006] As a preferred embodiment, the portion of the third electrode located on the third surface is annular, and when the fourth electrode extends to the second outer annular surface, the outer diameter of the annular surface is configured to be smaller than the outer diameter of the second substrate, and when the fourth electrode extends to the second inner annular surface, the inner diameter of the annular surface is configured to be larger than the diameter of the second through hole; the portion of the fourth electrode located on the fourth surface is a notched annular surface, and the portion of the third electrode extending to the fourth surface is located at the corresponding notch.

[0007] Further preferably, the first piezoelectric sheet includes a first substrate, a first electrode, and a second electrode. The outer diameter of the first substrate is equal to the outer diameter of the second substrate. The first substrate has a first surface and a second surface that are axially opposed, and a first outer annular surface located radially outward. The first electrode is disposed on the first surface and extends to the first outer annular surface. The fourth electrode extends to the second outer annular surface and is configured to communicate with the first electrode. The second electrode is disposed on the second surface, and its outer diameter is equal to the outer diameter of the annular portion of the third electrode located on the third surface. The second electrode is configured to communicate with the third electrode. The third electrode extends to the fourth surface through the second inner annular surface.

[0008] Further preferably, the first piezoelectric sheet includes a first substrate, a first electrode, and a second electrode. The first substrate has a first through hole penetrating its thickness, and its size is the same as that of the second substrate. The first substrate has a first surface and a second surface opposite to each other along the axial direction, and a first outer annular surface located radially outward and a first inner annular surface located radially inward. The first electrode is disposed on the first surface and extends to the first inner annular surface. The fourth electrode extends to the second inner annular surface and is configured to communicate with the first electrode. The second electrode is disposed on the second surface, and its inner diameter is equal to the inner diameter of the annular portion of the third electrode located on the third surface. The second electrode is configured to communicate with the third electrode. The third electrode extends to the fourth surface through the second outer annular surface.

[0009] Further preferably, the first piezoelectric sheet includes a first substrate, a first electrode, and a second electrode. The first substrate has a first through-hole penetrating its thickness, and its size is the same as that of the second substrate. The first substrate has a first surface and a second surface opposite to each other along the axial direction, and a first outer annular surface located radially outward and a first inner annular surface located radially inward. The first electrode is disposed on the first surface and extends to the first inner annular surface. The fourth electrode extends to the second inner annular surface and is configured to communicate with the first electrode. The second electrode is disposed on the second surface, and its inner diameter is equal to the inner diameter of the annular portion of the third electrode located on the third surface. The second electrode is configured to communicate with the third electrode. The third electrode extends to the fourth surface through the second inner annular surface.

[0010] Further preferably, the first piezoelectric sheet includes a first substrate, a first electrode, and a second electrode. The outer diameter of the first substrate is equal to the outer diameter of the second substrate. The first substrate has a first surface and a second surface that are axially opposed, and a first outer annular surface located radially outward. The first electrode is disposed on the first surface and extends to the first outer annular surface. The fourth electrode extends to the second outer annular surface and is configured to communicate with the first electrode. The second electrode is disposed on the second surface, and its outer diameter is equal to the outer diameter of the annular portion of the third electrode located on the third surface. The second electrode is configured to communicate with the third electrode. The third electrode extends to the fourth surface through the second outer annular surface.

[0011] Another technical solution adopted in this application is: a flanged electrode type piezoelectric stack, including at least one second piezoelectric sheet, the second piezoelectric sheet including a second substrate, a third electrode and a fourth electrode, the second substrate having a third surface and a fourth surface opposite to each other along the axial direction, and a second outer ring surface located radially outward, the third electrode being disposed on the third surface and extending to the fourth surface through the second outer ring surface, the fourth electrode being disposed on the fourth surface and extending to the second outer ring surface, the third electrode and the fourth electrode being mutually insulated; when stacked, at least one second piezoelectric sheet is configured to be connected to the corresponding electrode of the first piezoelectric sheet, and / or a plurality of second piezoelectric sheets are connected sequentially.

[0012] As a preferred embodiment, the portion of the third electrode located on the third surface is circular, and its outer diameter is configured to be smaller than the diameter of the second substrate; the portion of the fourth electrode located on the fourth surface is circular with a notch, and the portion of the third electrode extending to the fourth surface is located at the corresponding notch.

[0013] Further preferably, the first piezoelectric sheet includes a first substrate, a first electrode, and a second electrode. The outer diameter of the first substrate is equal to the outer diameter of the second substrate. The first substrate has a first surface and a second surface that are axially opposed to each other, and a first outer annular surface located radially outward. The first electrode is disposed on the first surface and extends to the first outer annular surface. The fourth electrode extends to the second outer annular surface and is configured to communicate with the first electrode. The second electrode is disposed on the second surface, and its outer diameter is equal to the diameter of the circular portion of the third electrode located on the third surface. The second electrode is configured to communicate with the third electrode. The third electrode extends through the second outer annular surface to the edge of the fourth surface.

[0014] Further preferably, the first piezoelectric sheet includes a first substrate, a first electrode, and a second electrode. The outer diameter of the first substrate is equal to the outer diameter of the second substrate. The first substrate has a first surface and a second surface that are axially opposed, and a first outer annular surface located radially outward. The first electrode is disposed on the first surface and extends to the first outer annular surface. The fourth electrode extends to the second outer annular surface and is configured to communicate with the first electrode. The second electrode is disposed on the second surface, and its outer diameter is equal to the diameter of the circular portion of the third electrode located on the third surface. The second electrode is configured to communicate with the third electrode. The third electrode extends through the second outer annular surface to the center of the fourth surface.

[0015] Compared with the prior art, the beneficial effects of this application are as follows: (1) By adopting the design of the flanged electrode, the third electrode and the fourth electrode are extended from the surface of the second piezoelectric sheet to the second outer ring surface or the second inner ring surface, respectively, realizing the arrangement of the electrodes in three-dimensional space. This structure does not require the complex internal wires or external jumpers in the traditional design. Stable and reliable electrical connection can be achieved through the direct contact of the electrodes during stacking. This not only simplifies the assembly process and reduces the manufacturing cost, but also fundamentally avoids the risk of failure caused by internal wire breakage or poor connection, and significantly improves the overall reliability and life of the piezoelectric stack.

[0016] (2) This application provides specific electrode configuration methods applicable to piezoelectric sheets with and without through holes, enabling reliable connections between the first piezoelectric sheet and the second piezoelectric sheet, and / or between several second piezoelectric sheets themselves in various forms. This modular and standardized design greatly enhances the versatility of piezoelectric stacks, allowing for flexible selection and combination of different types of piezoelectric sheets according to different performance requirements such as output force, displacement, and stiffness, to meet diverse application scenario needs.

[0017] (3) In this application, since the third electrode and the fourth electrode are designed to be mutually insulated, the risk of short circuit between layers and between electrodes in the same layer can be effectively reduced when stacked. This clear electrical isolation design also reduces the possibility of signal crosstalk, which is conducive to the piezoelectric stack maintaining stable and accurate response characteristics under high-frequency dynamic conditions and improving its performance in high-precision control applications. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the first stacked three-dimensional structure of this utility model.

[0019] Figure 2 This is an exploded view of the first stacked three-dimensional structure of this utility model. The left column of the figure is a top view and the right column is a bottom view.

[0020] Figure 3 This is a schematic diagram of the second stacked three-dimensional structure of this utility model.

[0021] Figure 4 This is an exploded view of the second stacked three-dimensional structure of this utility model. The left column of the figure is a top view and the right column is a bottom view.

[0022] Figure 5 This is a schematic diagram of the third stacked three-dimensional structure of this utility model.

[0023] Figure 6 This is an exploded view of the third stacked three-dimensional structure of this utility model. The left column of the figure is a top view and the right column is a bottom view.

[0024] Figure 7 This is a schematic diagram of the fourth stacked three-dimensional structure of this utility model.

[0025] Figure 8 This is an exploded view of the fourth stacked three-dimensional structure of this utility model. The left column of the figure is a top view and the right column is a bottom view.

[0026] Figure 9 This is a schematic diagram of the fifth stacked three-dimensional structure of this utility model.

[0027] Figure 10 This is the fifth exploded view of the stacked three-dimensional structure of this utility model. The left column of the figure is a top view and the right column is a bottom view.

[0028] Figure 11 This is a schematic diagram of the sixth stacked three-dimensional structure of this utility model.

[0029] Figure 12 This is an exploded view of the sixth stacked three-dimensional structure of this utility model. The left column of the figure is a top view and the right column is a bottom view.

[0030] In the figure: 1. First piezoelectric element; 11. First substrate; 12. First electrode; 13. Second electrode; 14. First through hole; 2. Second piezoelectric element; 21. Second substrate; 22. Third electrode; 23. Fourth electrode; 24. Second through hole. Detailed Implementation

[0031] The present application will be further described below with reference to specific embodiments. It should be noted that, without conflict, the various embodiments or technical features described below can be arbitrarily combined to form new embodiments.

[0032] In the description of this application, it should be noted that the terms "center", "lateral", "longitudinal", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", etc., which indicate the orientation and positional relationship based on the orientation or positional relationship shown in the accompanying drawings, are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and should not be construed as limiting the specific protection scope of this application.

[0033] It should be noted that the terms "first," "second," etc., in the specification and claims of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence.

[0034] The terms “comprising” and “having”, and any variations thereof, in the specification and claims of this application are intended to cover non-exclusive inclusion, for example, a process, method, system, product, or device that includes a series of steps or units is not necessarily limited to those steps or units that are explicitly listed, but may include other steps or units that are not explicitly listed or that are inherent to such process, method, product, or device.

[0035] A preferred embodiment of this application, such as Figures 1 to 8As shown, a flanged electrode type piezoelectric stack includes at least one second piezoelectric sheet 2. The second piezoelectric sheet 2 includes a second substrate 21, a third electrode 22, and a fourth electrode 23. The second substrate 21 is provided with a second through hole 24 penetrating its thickness. The second substrate 21 has a third surface and a fourth surface opposite to each other along the axial direction, as well as a second outer ring surface located radially outward and a second inner ring surface located radially inward. The third electrode 22 is disposed on the third surface and extends to the fourth surface through the second outer ring surface or the second inner ring surface. The fourth electrode 23 is disposed on the fourth surface and extends to the second outer ring surface or the second inner ring surface. The third electrode 22 and the fourth electrode 23 are insulated from each other. When stacked, at least one second piezoelectric sheet 2 is configured to be connected to the corresponding electrode of the first piezoelectric sheet 1, and / or a plurality of second piezoelectric sheets 2 are connected sequentially.

[0036] More specifically, the portion of the third electrode 22 located on the third surface is annular, and when the fourth electrode 23 extends to the second outer annular surface, the outer diameter of the annular surface is configured to be smaller than the outer diameter of the second substrate 21. When the fourth electrode 23 extends to the second inner annular surface, the inner diameter of the annular surface is configured to be larger than the diameter of the second through hole 24. The portion of the fourth electrode 23 located on the fourth surface is a notched annular surface, and the portion of the third electrode 22 extending to the fourth surface is located at the corresponding notch.

[0037] This embodiment ensures that the electrodes are precisely aligned and connected when adjacent piezoelectric sheets are stacked by precisely designing the shape of the electrodes on the surface and their dimensional relationship with the through holes and outer diameter, while maintaining the necessary insulation interval. This ingenious layout allows multilayer piezoelectric sheets to be tightly stacked without additional connection space, thereby integrating more piezoelectric layers in the same volume, which helps to improve the total output force and displacement of the stack, achieving a compact structure and improved performance.

[0038] In this embodiment, since the third electrode 22 and the fourth electrode 23 are designed to be mutually insulated, the risk of short circuits between layers and between electrodes in the same layer can be effectively reduced when stacked. This clear electrical isolation design also reduces the possibility of signal crosstalk, which is conducive to the piezoelectric stack maintaining stable and accurate response characteristics under high-frequency dynamic conditions and improving its performance in high-precision control applications. As for the specific size settings, they can be adjusted by those skilled in the art according to actual needs.

[0039] Based on the above-described toroidal piezoelectric stack design, this embodiment provides four specific stack structures: The first type of stacking, such as Figures 1 to 2As shown, the first piezoelectric sheet 1 includes a first substrate 11, a first electrode 12, and a second electrode 13. The outer diameter of the first substrate 11 is equal to the outer diameter of the second substrate 21. The first substrate 11 has a first surface and a second surface that are axially opposite each other, and a first outer ring surface located radially outward. The first electrode 12 is disposed on the first surface and extends to the first outer ring surface. The fourth electrode 23 extends to the second outer ring surface and is configured to communicate with the first electrode 12. The second electrode 13 is disposed on the second surface, and its outer diameter is equal to the outer diameter of the annular portion of the third electrode 22 located on the third surface. The second electrode 13 is configured to communicate with the third electrode 22. The third electrode 22 extends to the fourth surface through the second inner ring surface.

[0040] The second type of stacking, such as Figures 3 to 4 As shown, the first piezoelectric sheet 1 includes a first substrate 11, a first electrode 12, and a second electrode 13. The first substrate 11 has a first through hole 14 penetrating its thickness, and its size is the same as that of the second substrate 21. The first substrate 11 has a first surface and a second surface that are axially opposite each other, as well as a first outer ring surface located radially outward and a first inner ring surface located radially inward. The first electrode 12 is disposed on the first surface and extends to the first inner ring surface. The fourth electrode 23 extends to the second inner ring surface and is configured to communicate with the first electrode 12. The second electrode 13 is disposed on the second surface, and its inner diameter is equal to the inner diameter of the annular portion of the third electrode 22 located on the third surface. The second electrode 13 is configured to communicate with the third electrode 22. The third electrode 22 extends to the fourth surface through the second outer ring surface.

[0041] In the two stacked structures described above, it is clear that the positive and negative electrodes of each piezoelectric element in the stack are connected from the outer ring surface and the inner ring surface, respectively. The difference between the two stacked structures is that when the stacks are connected to the power supply in the same way, if the positive electrode of the first stack is connected from the outer ring surface and the negative electrode is connected from the inner ring surface, then the second stack is exactly the opposite, that is, the positive electrode is connected from the inner ring surface and the negative electrode is connected from the outer ring surface.

[0042] The third type of stacking, such as Figures 5 to 6 As shown, the first piezoelectric sheet 1 includes a first substrate 11, a first electrode 12, and a second electrode 13. The first substrate 11 has a first through hole 14 penetrating its thickness, and its size is the same as that of the second substrate 21. The first substrate 11 has a first surface and a second surface that are axially opposite each other, as well as a first outer ring surface located radially outward and a first inner ring surface located radially inward. The first electrode 12 is disposed on the first surface and extends to the first inner ring surface. The fourth electrode 23 extends to the second inner ring surface and is configured to communicate with the first electrode 12. The second electrode 13 is disposed on the second surface, and its inner diameter is equal to the inner diameter of the annular portion of the third electrode 22 located on the third surface. The second electrode 13 is configured to communicate with the third electrode 22. The third electrode 22 extends to the fourth surface through the second inner ring surface.

[0043] In the third stacked structure described above, it is clear that the positive and negative electrodes of each piezoelectric element in the stack are connected from the inner ring surface.

[0044] The fourth type of stacking, such as Figures 7 to 8 As shown, the first piezoelectric sheet 1 includes a first substrate 11, a first electrode 12, and a second electrode 13. The outer diameter of the first substrate 11 is equal to the outer diameter of the second substrate 21. The first substrate 11 has a first surface and a second surface that are axially opposed to each other, and a first outer ring surface located radially outward. The first electrode 12 is disposed on the first surface and extends to the first outer ring surface. The fourth electrode 23 extends to the second outer ring surface and is configured to communicate with the first electrode 12. The second electrode 13 is disposed on the second surface, and its outer diameter is equal to the outer diameter of the annular portion of the third electrode 22 located on the third surface. The second electrode 13 is configured to communicate with the third electrode 22. The third electrode 22 extends to the fourth surface through the second outer ring surface.

[0045] In the fourth stacked structure described above, it is clear that the positive and negative electrodes of each piezoelectric element in the stack are connected from the outer ring surface.

[0046] Another preferred embodiment of this utility model is as follows: Figures 9 to 12 As shown, a flanged electrode type piezoelectric stack includes at least one second piezoelectric sheet 2. The second piezoelectric sheet 2 includes a second substrate 21, a third electrode 22, and a fourth electrode 23. The second substrate 21 has a third surface and a fourth surface that are axially opposed, and a second outer ring surface located radially outward. The third electrode 22 is disposed on the third surface and extends to the fourth surface through the second outer ring surface. The fourth electrode 23 is disposed on the fourth surface and extends to the second outer ring surface. The third electrode 22 and the fourth electrode 23 are insulated from each other. When stacked, at least one second piezoelectric sheet 2 is configured to be connected to the corresponding electrode of the first piezoelectric sheet 1, and / or a plurality of second piezoelectric sheets 2 are connected sequentially.

[0047] More specifically, the portion of the third electrode 22 located on the third surface is circular, and its outer diameter is configured to be smaller than the diameter of the second substrate 21; the portion of the fourth electrode 23 located on the fourth surface is circular with a notch, and the portion of the third electrode 22 extending to the fourth surface is located at the corresponding notch.

[0048] The above-described dimensional design ensures insulation between electrodes and prevents short circuits. The specific dimensions can be adjusted by those skilled in the art according to actual needs.

[0049] Based on the above circular piezoelectric stack design, this embodiment provides two specific stack structures: The fifth type of stacking, such as Figures 9 to 10As shown, the first piezoelectric sheet 1 includes a first substrate 11, a first electrode 12, and a second electrode 13. The outer diameter of the first substrate 11 is equal to the outer diameter of the second substrate 21. The first substrate 11 has a first surface and a second surface that are axially opposed to each other, and a first outer ring surface located radially outward. The first electrode 12 is disposed on the first surface and extends to the first outer ring surface. The fourth electrode 23 extends to the second outer ring surface and is configured to communicate with the first electrode 12. The second electrode 13 is disposed on the second surface, and its outer diameter is equal to the diameter of the circular portion of the third electrode 22 located on the third surface. The second electrode 13 is configured to communicate with the third electrode 22. The third electrode 22 extends through the second outer ring surface to the edge of the fourth surface.

[0050] The sixth type of stacking, such as Figures 11 to 12 As shown, the first piezoelectric sheet 1 includes a first substrate 11, a first electrode 12, and a second electrode 13. The outer diameter of the first substrate 11 is equal to the outer diameter of the second substrate 21. The first substrate 11 has a first surface and a second surface that are axially opposed to each other, and a first outer ring surface located radially outward. The first electrode 12 is disposed on the first surface and extends to the first outer ring surface. The fourth electrode 23 extends to the second outer ring surface and is configured to communicate with the first electrode 12. The second electrode 13 is disposed on the second surface, and its outer diameter is equal to the diameter of the circular portion of the third electrode 22 located on the third surface. The second electrode 13 is configured to communicate with the third electrode 22. The third electrode 22 extends through the second outer ring surface to the center of the fourth surface.

[0051] In the two stacked structures described above, it is clear that the positive and negative electrodes of each piezoelectric element in the stack are connected from the outer ring surface. The difference is that in the fifth stack, the portion of the third electrode 22 that is turned to the fourth surface is located at the edge, while in the sixth stack, the portion of the third electrode 22 that is turned to the fourth surface is located in the middle. The main difference between the two is that they provide connection areas at different locations. Based on the specific design of different products, the connection terminal positions of their external circuits are different. The two stacked structures in this embodiment can be adapted to each other.

[0052] In the above scheme, by designing the specific structure of the first piezoelectric element 1 and / or the second piezoelectric element 2, the piezoelectric stack can be stacked without quantity limit, and the piezoelectric elements are connected in parallel, which can be driven at a lower voltage and has higher power. This piezoelectric stack can be used in multiple fields, such as for buzzers. A metal sheet can be connected to the end of the piezoelectric stack. The diameter of the metal sheet is larger than the diameter of the stack. The vibration of the stack drives the metal sheet to vibrate and produce sound at the same time.

[0053] The basic principles, main features, and advantages of this application have been described above. Those skilled in the art should understand that this application is not limited to the above embodiments. The embodiments and descriptions in the specification are merely the principles of this application. Various changes and modifications can be made to this application without departing from its spirit and scope, and all such changes and modifications fall within the scope of the claims. The scope of protection claimed by this application is defined by the appended claims and their equivalents.

Claims

1. A piezoelectric stack with flanged electrodes, characterized in that, The device includes at least one second piezoelectric element, which comprises a second substrate, a third electrode, and a fourth electrode. The second substrate has a second through-hole extending through its thickness. The second substrate has a third surface and a fourth surface opposite each other along an axial direction, and a second outer annular surface located radially outward and a second inner annular surface located radially inward. The third electrode is disposed on the third surface and extends to the fourth surface through the second outer annular surface or the second inner annular surface. The fourth electrode is disposed on the fourth surface and extends to the second outer annular surface or the second inner annular surface. The third electrode and the fourth electrode are insulated from each other. When stacked, at least one second piezoelectric element is configured to be connected to a corresponding electrode of a first piezoelectric element, and / or a plurality of second piezoelectric elements are connected sequentially.

2. The flanged electrode type piezoelectric stack as described in claim 1, characterized in that, The portion of the third electrode located on the third surface is annular. When the fourth electrode extends to the second outer annular surface, the outer diameter of the annular surface is configured to be smaller than the outer diameter of the second substrate. When the fourth electrode extends to the second inner annular surface, the inner diameter of the annular surface is configured to be larger than the diameter of the second through hole. The portion of the fourth electrode located on the fourth surface is a notched annular surface, and the portion of the third electrode extending to the fourth surface is located at the corresponding notch.

3. The flanged electrode type piezoelectric stack as described in claim 2, characterized in that, The first piezoelectric element includes a first substrate, a first electrode, and a second electrode. The outer diameter of the first substrate is equal to the outer diameter of the second substrate. The first substrate has a first surface and a second surface that are axially opposed to each other, and a first outer annular surface located radially outward. The first electrode is disposed on the first surface and extends to the first outer annular surface. The fourth electrode extends to the second outer annular surface and is configured to communicate with the first electrode. The second electrode is disposed on the second surface, and its outer diameter is equal to the outer diameter of the annular portion of the third electrode located on the third surface. The second electrode is configured to communicate with the third electrode. The third electrode extends to the fourth surface through the second inner annular surface.

4. The flanged electrode type piezoelectric stack as described in claim 2, characterized in that, The first piezoelectric sheet includes a first substrate, a first electrode, and a second electrode. The first substrate has a first through hole penetrating its thickness, and the size of the hole is the same as that of the second substrate. The first substrate has a first surface and a second surface that are axially opposed, as well as a first outer annular surface located radially outward and a first inner annular surface located radially inward. The first electrode is disposed on the first surface and extends to the first inner annular surface. The fourth electrode extends to the second inner annular surface and is configured to communicate with the first electrode. The second electrode is disposed on the second surface, and its inner diameter is equal to the inner diameter of the annular portion of the third electrode located on the third surface. The second electrode is configured to communicate with the third electrode. The third electrode extends to the fourth surface through the second outer annular surface.

5. The flanged electrode type piezoelectric stack as described in claim 2, characterized in that, The first piezoelectric sheet includes a first substrate, a first electrode, and a second electrode. The first substrate has a first through hole penetrating its thickness, and the size of the hole is the same as that of the second substrate. The first substrate has a first surface and a second surface that are axially opposed, as well as a first outer annular surface located radially outward and a first inner annular surface located radially inward. The first electrode is disposed on the first surface and extends to the first inner annular surface. The fourth electrode extends to the second inner annular surface and is configured to communicate with the first electrode. The second electrode is disposed on the second surface, and its inner diameter is equal to the inner diameter of the annular portion of the third electrode located on the third surface. The second electrode is configured to communicate with the third electrode. The third electrode extends to the fourth surface through the second inner annular surface.

6. The flanged electrode type piezoelectric stack as described in claim 2, characterized in that, The first piezoelectric element includes a first substrate, a first electrode, and a second electrode. The outer diameter of the first substrate is equal to the outer diameter of the second substrate. The first substrate has a first surface and a second surface that are axially opposed to each other, and a first outer annular surface located radially outward. The first electrode is disposed on the first surface and extends to the first outer annular surface. The fourth electrode extends to the second outer annular surface and is configured to communicate with the first electrode. The second electrode is disposed on the second surface, and its outer diameter is equal to the outer diameter of the annular portion of the third electrode located on the third surface. The second electrode is configured to communicate with the third electrode. The third electrode extends to the fourth surface through the second outer annular surface.

7. A piezoelectric stack with flanged electrodes, characterized in that, The device includes at least one second piezoelectric element, which comprises a second substrate, a third electrode, and a fourth electrode. The second substrate has a third surface and a fourth surface that are axially opposed, and a second outer annular surface located radially outward. The third electrode is disposed on the third surface and extends to the fourth surface through the second outer annular surface. The fourth electrode is disposed on the fourth surface and extends to the second outer annular surface. The third electrode and the fourth electrode are insulated from each other. When stacked, at least one second piezoelectric element is configured to be connected to a corresponding electrode of a first piezoelectric element, and / or a plurality of second piezoelectric elements are connected sequentially.

8. The flanged electrode type piezoelectric stack as described in claim 7, characterized in that, The portion of the third electrode located on the third surface is circular, and its outer diameter is configured to be smaller than the diameter of the second substrate; the portion of the fourth electrode located on the fourth surface is circular with a notch, and the portion of the third electrode extending to the fourth surface is located at the corresponding notch.

9. A flanged electrode type piezoelectric stack as described in claim 8, characterized in that, The first piezoelectric element includes a first substrate, a first electrode, and a second electrode. The outer diameter of the first substrate is equal to the outer diameter of the second substrate. The first substrate has a first surface and a second surface that are axially opposed, and a first outer annular surface located radially outward. The first electrode is disposed on the first surface and extends to the first outer annular surface. The fourth electrode extends to the second outer annular surface and is configured to communicate with the first electrode. The second electrode is disposed on the second surface, and its outer diameter is equal to the diameter of the circular portion of the third electrode located on the third surface. The second electrode is configured to communicate with the third electrode. The third electrode extends through the second outer annular surface to the edge of the fourth surface.

10. A flanged electrode type piezoelectric stack as described in claim 8, characterized in that, The first piezoelectric element includes a first substrate, a first electrode, and a second electrode. The outer diameter of the first substrate is equal to the outer diameter of the second substrate. The first substrate has a first surface and a second surface that are axially opposed to each other, and a first outer annular surface located radially outward. The first electrode is disposed on the first surface and extends to the first outer annular surface. The fourth electrode extends to the second outer annular surface and is configured to communicate with the first electrode. The second electrode is disposed on the second surface, and its outer diameter is equal to the diameter of the circular portion of the third electrode located on the third surface. The second electrode is configured to communicate with the third electrode. The third electrode extends through the second outer annular surface to the center of the fourth surface.

Images