A dual-channel controlled spin plate wave source excitation device and preparation method thereof

Abstract

The present invention relates to a dual-channel controlled spin plate wave source excitation device and a preparation method thereof, the device comprises a base, a piezoelectric vibration component array is mounted on the base, the piezoelectric vibration component array is connected to an external dual-channel voltage excitation source, the piezoelectric vibration component array comprises four piezoelectric sheets arranged in a square matrix, wherein two piezoelectric sheets at a diagonal position in the piezoelectric vibration component array are connected to one channel of the dual-channel voltage excitation source, and two piezoelectric sheets at another diagonal position in the piezoelectric vibration component array are connected to another channel of the dual-channel voltage excitation source. Compared with the prior art, the present invention first solves the actual excitation problem of the spin plate wave source, and provides a detailed preparation method of the spin plate wave source excitation device, which has the advantages of being portable and detachable, convenient to prepare, and low cost.

Description

Technical Field

[0001] The present invention relates to the technical field of elastic wave excitation, and in particular to a dual-channel controlled spin plate wave source excitation device and a preparation method thereof. Background Art

[0002] The study of spin has promoted people's understanding of the foundations of symmetry and topology from the quantum level to the classical system. Spin is one of the most important properties in the field of condensed matter physics and quantum mechanics, and is also the basis of topological states. Macroscopically, spin can be reflected in propagation related to directional selectivity, such as unidirectional propagation.

[0003] In recent years, the concept of topology has been rapidly extended to classical wave systems based on periodic structures (such as acoustic metamaterials). Due to its flexible and controllable structure, periodic structures and the classical wave systems therein have become a good platform for testing or realizing many topological physical phenomena. A large number of researchers have conducted research on analog Hall effect, spin Hall effect, valley Hall effect, Weyl point, high-order topology, etc. in acoustic or mechanical systems. A notable feature of topological structure is that waves have a unidirectional transmission phenomenon along the topological boundary composed of two topological antiphase parts. For example, on the topological boundary based on analog spin Hall effect, valley Hall effect, etc. in phononic crystal plate, the plate wave spin source with a specific polarization direction can selectively excite unidirectional boundary states, and the propagation direction of the boundary state of its topological projection is spin-dependent.

[0004] However, there are very few experimental reports on unidirectional transmission boundary states excited by spin-plate wave sources. Therefore, it is urgent to design a spin-plate wave source excitation device to provide key evidence for experimental research on spin-dependent unidirectional transmission and provide an experimental basis for the design and development of related devices. Summary of the invention

[0005] The purpose of the present invention is to overcome the defects of the above-mentioned prior art and to provide a dual-channel controlled spin plate wave source excitation device and a preparation method thereof.

[0006] The objective of the present invention can be achieved through the following technical scheme: a dual-channel controlled spin plate wave source excitation device, comprising a base, on which a piezoelectric vibration component array is mounted, the piezoelectric vibration component array is connected to an external dual-channel voltage excitation source, the piezoelectric vibration component array comprises four piezoelectric sheets arranged in a square matrix, wherein two piezoelectric sheets at a diagonal position in the piezoelectric vibration component array are connected to one channel of the dual-channel voltage excitation source, and two piezoelectric sheets at another diagonal position in the piezoelectric vibration component array are connected to another channel of the dual-channel voltage excitation source.

[0007] Furthermore, the size, material and polarization direction of the four piezoelectric sheets in the piezoelectric vibration component array are the same.

[0008] Furthermore, the piezoelectric sheet is specifically a disc, a ring or a square sheet structure.

[0009] Furthermore, the piezoelectric sheet is mounted on the base via a connecting fixture.

[0010] Furthermore, the connecting and fixing member is specifically epoxy resin.

[0011] Furthermore, the base is specifically a metal sheet.

[0012] Furthermore, the upper surface and the lower surface of the piezoelectric sheet are respectively connected with a first wire and a second wire, and the first wire and the second wire are respectively connected to the positive electrode or the negative electrode of one channel in a dual-channel voltage excitation source.

[0013] Furthermore, among the two piezoelectric sheets at a diagonal position in the piezoelectric vibration component array, the upper surface of one piezoelectric sheet is connected to the positive electrode and the lower surface is connected to the negative electrode, and the upper surface of the other piezoelectric sheet is connected to the negative electrode and the lower surface is connected to the positive electrode.

[0014] Furthermore, both channels of the dual-channel voltage excitation source output multi-cycle sinusoidal pulse voltage signals, and there is a phase difference of π / 2 between the two channels with respect to the center frequency.

[0015] Furthermore, the size of the piezoelectric sheet and the distance between two adjacent piezoelectric sheets are determined according to the wavelength corresponding to the set working frequency of the spin plate wave source.

[0016] A method for preparing a dual-channel controlled spin plate wave source excitation device comprises the following steps:

[0017] S1. According to the wavelength data corresponding to the frequency band required by the spin plate wave source, the sizes of the four piezoelectric sheets in the piezoelectric vibration component array are selected;

[0018] S2, determining the distance between two adjacent piezoelectric sheets according to the wavelength data corresponding to the frequency band required by the spin plate wave source and the size data of the piezoelectric sheets;

[0019] S3, fix a piece of double-sided tape to the work surface, determine the size according to step S1 and step S2, and mark four positions for fixing the piezoelectric piece on the double-sided tape;

[0020] S4. Fix a wire at each of the four locations marked on the double-sided tape;

[0021] S5. Apply a thin layer of epoxy resin to the four locations marked on the double-sided tape.

[0022] S6, placing the four piezoelectric sheets in the marked positions in sequence, and pressing them so that the four piezoelectric sheets are flat and initially fixed in the predetermined positions;

[0023] S7, detecting whether each wire is connected to the lower surface of the corresponding piezoelectric sheet, if not, returning to execute steps S4 to S6 until each wire is connected to the lower surface of the corresponding piezoelectric sheet;

[0024] S8, checking whether each wire is connected to the lower surfaces of the other three piezoelectric sheets that do not correspond to each other, and if so, returning to steps S4 to S7 until each wire is not connected to the lower surfaces of the other three piezoelectric sheets that do not correspond to each other;

[0025] S9. When the piezoelectric sheet and the wire are initially fixed but the epoxy resin is not completely cured, remove the double-sided tape;

[0026] S10, fix the double-sided tape on the workbench again, apply a thin layer of epoxy resin, and then fix the four piezoelectric sheets and wires that have been initially fixed into the epoxy resin and press to fix;

[0027] S11, executing steps S7-S8 again, if each wire is well connected with the corresponding piezoelectric sheet, and each wire is not connected with the lower surfaces of the other three piezoelectric sheets, then place and cure for 2 to 3 hours to obtain a piezoelectric vibration component;

[0028] S12, clean up the double-sided tape, check the cured piezoelectric vibration component, and check whether the wire and the bottom of the piezoelectric vibration component are insulated. If not, return to step S10 and add a layer of epoxy resin under the component; if it is insulated, execute step S13;

[0029] S13, fixing the piezoelectric vibration assembly to a metal sheet using epoxy resin, and welding wires to the upper surfaces of the four piezoelectric sheets to form an integral excitation device;

[0030] S14, connecting the four piezoelectric sheets to an external dual-channel voltage excitation source: two piezoelectric sheets located at a diagonal position in the piezoelectric vibration component array share an excitation voltage signal of one channel, wherein the upper surface of one piezoelectric sheet is connected to a positive electrode and the lower surface is connected to a negative electrode, and the upper surface of the other piezoelectric sheet is connected to a negative electrode and the lower surface is connected to a positive electrode;

[0031] Two piezoelectric sheets at another diagonal position in the piezoelectric vibration component array share an excitation voltage signal of another channel, wherein the upper surface of one piezoelectric sheet is connected to the positive electrode and the lower surface is connected to the negative electrode, and the upper surface of the other piezoelectric sheet is connected to the negative electrode and the lower surface is connected to the positive electrode;

[0032] The two channels of the dual-channel voltage excitation source both output multi-cycle sinusoidal pulse voltage signals, and there is a phase difference of π / 2 between the two channels with respect to the center frequency.

[0033] Compared with the prior art, the present invention has the following advantages:

[0034] 1. The present invention sets a piezoelectric vibration component array, designs the piezoelectric vibration component array to include four piezoelectric sheets arranged in a square matrix, and connects two piezoelectric sheets at a diagonal position in the piezoelectric vibration component array to one channel of a dual-channel voltage excitation source, and two piezoelectric sheets at another diagonal position in the piezoelectric vibration component array are connected to the other channel of the dual-channel voltage excitation source, thereby connecting the dual-channel voltage signal to the piezoelectric vibration component, thereby being able to spontaneously generate spin plate waves, which can be used in related experiments and practical applications of spin plate waves, and provide a basis for related experimental research.

[0035] 2. When preparing the spin plate wave source excitation device, the present invention repeatedly uses double-sided tape to assist, which can not only effectively reduce the difficulty of production, but also ensure the accuracy of processing and production; in addition, the present invention is based on the wavelength data corresponding to the operating frequency to determine the size of the piezoelectric sheet in the piezoelectric vibration component array and the distance between adjacent piezoelectric sheets, so that the subsequently generated spin plate waves can meet the design requirements and ensure the accuracy of the device.

[0036] 3. The spin plate wave source excitation device proposed in the present invention can be pre-packaged to make it a detachable and portable device, and the materials used in the present invention can be customized or purchased, with a simple structure and easy preparation. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 It is a structural schematic diagram of a dual-channel controlled spin plate wave source excitation device in an embodiment;

[0038] Figure 2 A schematic diagram of the disassembly of the installation structure of a single piezoelectric sheet in the embodiment;

[0039] Figure 3 A schematic diagram of the installation effect of a single piezoelectric sheet in the embodiment;

[0040] Figure 4 It is a schematic diagram of dual-channel sinusoidal pulse excitation voltage signal;

[0041] Figure 5 A schematic diagram of the spin plate wave effect produced in the embodiment;

[0042] Explanation of the markings in the figure: 1 to 4, piezoelectric sheets, 5, connecting fixture, 6, base, 7, first wire, 8, second wire. DETAILED DESCRIPTION

[0043] The present invention is described in detail below with reference to the accompanying drawings and specific embodiments.

[0044] Example

[0045] like Figures 1 to 3 As shown, a dual-channel controlled spin plate wave source excitation device includes a base 6, on which a piezoelectric vibration component array is installed, and the piezoelectric vibration component array is connected to an external dual-channel voltage excitation source. The piezoelectric vibration component array includes four piezoelectric sheets 1 to 4 arranged in a square matrix, wherein two piezoelectric sheets (1 and 3) at a diagonal position in the piezoelectric vibration component array are connected to one channel of the dual-channel voltage excitation source, and two piezoelectric sheets (2 and 4) at another diagonal position in the piezoelectric vibration component array are connected to another channel of the dual-channel voltage excitation source, and the piezoelectric sheets 1 to 4 are respectively installed on the base 6 through a connecting fixture 5. The piezoelectric vibration components are connected to the base 6 through the connecting fixture 5, and the base 6 is used to fix the spin plate wave source excitation device to form a whole; each piezoelectric sheet in the piezoelectric vibration component array receives an external input excitation voltage signal, converts the voltage signal into mechanical vibration, and transmits it to the surface of the structure through the connecting fixture 5 and the base 6 to complete the excitation of the elastic wave spin source.

[0046] In addition, the upper surface and the lower surface of the piezoelectric sheet are respectively connected with a first wire 7 and a second wire 8, and the first wire 7 and the second wire 8 are respectively connected to the positive electrode or the negative electrode of one channel in the dual-channel voltage excitation source. For two piezoelectric sheets at a diagonal position in the piezoelectric vibration component array, if the upper surface of one piezoelectric sheet is connected to the positive electrode and the lower surface is connected to the negative electrode, then the upper surface of the other piezoelectric sheet is connected to the negative electrode and the lower surface is connected to the positive electrode. For example Figure 1 In the embodiment, piezoelectric sheet 1 and piezoelectric sheet 3 share an excitation voltage signal of channel 1 (or channel 2), the upper surface of piezoelectric sheet 1 is connected to the positive electrode of the excitation voltage signal, and the lower surface is connected to the negative electrode, and the upper surface of piezoelectric sheet 3 is connected to the negative electrode, and the lower surface is connected to the positive electrode; piezoelectric sheet 2 and piezoelectric sheet 4 share an excitation voltage signal of channel 2 (or channel 1), the upper surface of piezoelectric sheet 2 is connected to the positive electrode, and the lower surface is connected to the negative electrode, and the upper surface of piezoelectric sheet 4 is connected to the negative electrode, and the lower surface is connected to the positive electrode;

[0047] Both channels of the dual-channel voltage excitation source output multi-cycle sinusoidal pulse voltage signals, and there is a phase difference of π / 2 between the two channels with respect to the center frequency;

[0048] The size of the piezoelectric sheet and the distance between two adjacent piezoelectric sheets are determined according to the wavelength corresponding to the set working frequency of the spin plate wave source. When the working frequency is 10 to 40 kHz, the diameter of the piezoelectric sheet can be selected to be 5 mm.

[0049] The four piezoelectric sheets 1 to 4 in the piezoelectric vibration component array have the same size, material and polarization direction. The piezoelectric sheets can be made of circular sheets, circular rings or square sheets.

[0050] In this embodiment, the connecting fixing member 5 is specifically epoxy resin, which has a high connection strength and can be used to fix the piezoelectric sheet to the base 6 and ensure the insulation between the lower surface of the piezoelectric sheet and the base 6;

[0051] The base 6 is specifically a metal sheet.

[0052] The present invention also provides a method for preparing a dual-channel controlled spin plate wave source excitation device, comprising the following steps:

[0053] S1. According to the wavelength data corresponding to the frequency band required by the spin plate wave source, the sizes of the four piezoelectric sheets in the piezoelectric vibration component array are selected;

[0054] S2, determining the distance between two adjacent piezoelectric sheets according to the wavelength data corresponding to the frequency band required by the spin plate wave source and the size data of the piezoelectric sheets;

[0055] S3, fix a piece of double-sided tape to the work surface, determine the size according to step S1 and step S2, and mark four positions for fixing the piezoelectric piece on the double-sided tape;

[0056] S4. Fix a wire at each of the four locations marked on the double-sided tape;

[0057] S5. Apply a thin layer of epoxy resin to the four locations marked on the double-sided tape.

[0058] S6, placing the four piezoelectric sheets in the marked positions in sequence, and pressing them so that the four piezoelectric sheets are flat and initially fixed in the predetermined positions;

[0059] S7, detecting whether each wire is connected to the lower surface of the corresponding piezoelectric sheet, if not, returning to execute steps S4 to S6 until each wire is connected to the lower surface of the corresponding piezoelectric sheet;

[0060] S8, checking whether each wire is connected to the lower surfaces of the other three piezoelectric sheets that do not correspond to each other, and if so, returning to steps S4 to S7 until each wire is not connected to the lower surfaces of the other three piezoelectric sheets that do not correspond to each other;

[0061] S9. When the piezoelectric sheet and the wire are initially fixed but the epoxy resin is not completely cured, remove the double-sided tape;

[0062] S10, fix the double-sided tape on the workbench again, apply a thin layer of epoxy resin, and then fix the four piezoelectric sheets and wires that have been initially fixed into the epoxy resin and press to fix;

[0063] S11, executing steps S7-S8 again, if each wire is well connected with the corresponding piezoelectric sheet, and each wire is not connected with the lower surfaces of the other three piezoelectric sheets, then place and cure for 2 to 3 hours to obtain a piezoelectric vibration component;

[0064] S12, clean up the double-sided tape, check the cured piezoelectric vibration component, and check whether the wire and the bottom of the piezoelectric vibration component are insulated. If not, return to step S10 and add a layer of epoxy resin under the component; if it is insulated, execute step S13;

[0065] S13, fixing the piezoelectric vibration assembly to a metal sheet using epoxy resin, and welding wires to the upper surfaces of the four piezoelectric sheets to form an integral excitation device;

[0066] S14, connecting the four piezoelectric sheets to an external dual-channel voltage excitation source: two piezoelectric sheets located at a diagonal position in the piezoelectric vibration component array share an excitation voltage signal of one channel, wherein the upper surface of one piezoelectric sheet is connected to a positive electrode and the lower surface is connected to a negative electrode, and the upper surface of the other piezoelectric sheet is connected to a negative electrode and the lower surface is connected to a positive electrode;

[0067] Two piezoelectric sheets at another diagonal position in the piezoelectric vibration component array share an excitation voltage signal of another channel, wherein the upper surface of one piezoelectric sheet is connected to the positive electrode and the lower surface is connected to the negative electrode, and the upper surface of the other piezoelectric sheet is connected to the negative electrode and the lower surface is connected to the positive electrode;

[0068] Both channels of the dual-channel voltage excitation source output multi-cycle sinusoidal pulse voltage signals, and there is a phase difference of π / 2 between the two channels with respect to the center frequency.

[0069] In this embodiment, the piezoelectric sheets are all cylindrical piezoelectric ceramics with a diameter of 5 mm, a thickness of 1.2 mm, and a material of PZT-5H. The polarization direction is along the thickness direction, and the distance between the centers of adjacent piezoelectric sheets is 6 mm. The operating frequency of the spin plate wave source excitation device composed of piezoelectric sheets and arrays of this size can at least cover the range of 10 to 40 kHz.

[0070] The specific preparation process includes:

[0071] (1) According to the wavelength data corresponding to the frequency band required by the spin plate wave source, the size of the piezoelectric piece is selected as: a cylindrical piezoelectric ceramic disc with a diameter of 5 mm and a thickness of 1.2 mm, and the material is PZT-5H. Usually, the diameter of the piezoelectric piece is less than one quarter of the corresponding wavelength;

[0072] (2) Determine the distance between two adjacent piezoelectric sheets according to the size of the piezoelectric sheets and the wavelength data corresponding to the frequency band required by the spin plate wave source. In this embodiment, the distance between the centers of adjacent piezoelectric sheets is 6 mm. Specifically, first determine the farthest connection distance between two adjacent piezoelectric sheets according to the wavelength data corresponding to the frequency band required by the spin plate wave source, and then determine the center distance between two adjacent piezoelectric sheets in combination with the size data of the piezoelectric sheets.

[0073] (3) Fix a piece of double-sided tape to the mounting platform (tabletop or workbench, etc.), and draw a position for fixing the piezoelectric piece on one side of the double-sided tape according to the dimensions determined in steps (1) and (2);

[0074] (4) Fix a wire at each of the four locations where the piezoelectric piece is fixed on the double-sided tape;

[0075] (5) Apply a thin layer of epoxy resin on the four locations where the piezoelectric film is fixed on the double-sided tape;

[0076] (6) placing piezoelectric sheet 1, piezoelectric sheet 2, piezoelectric sheet 3 and piezoelectric sheet 4 in the predetermined positions in sequence, and pressing the four piezoelectric sheets to be flatly fixed in the predetermined positions;

[0077] (7) Measure whether each wire is connected to the lower surface of the corresponding piezoelectric sheet. If not, check steps (4) to (6) to ensure that each wire is connected to the lower surface of the corresponding piezoelectric sheet.

[0078] (8) Check whether each wire is connected to the bottom surfaces of the other three piezoelectric sheets that do not correspond to each other. If so, adjust steps (4) to (7) to prevent each wire from being connected to the bottom surfaces of the other three piezoelectric sheets that do not correspond to each other.

[0079] (9) When the piezoelectric piece and the wire are initially fixed but the epoxy resin is not completely cured, remove the double-sided tape;

[0080] (10) Fix the double-sided tape on the mounting table again, apply a thin layer of epoxy resin, and then fix the four piezoelectric sheets and wires that were initially fixed above into the epoxy resin and press them to fix;

[0081] (11) Check steps (7) to (8) again. If each wire is well connected to the corresponding piezoelectric sheet, and each wire is not connected to the lower surfaces of the other three piezoelectric sheets, place and cure for 2 to 3 hours.

[0082] (12) Clean off the double-sided tape and check the components after curing in steps (10) to (11) to see whether the wires are insulated from the bottom of the components. If not, repeat step (10) to add a layer of epoxy resin under the components. If so, proceed to the next step.

[0083] (13) The structure formed in the above steps is fixed to a metal sheet (a thin aluminum sheet is used in this embodiment) with a size similar to that of the component and capable of covering the four piezoelectric sheets using epoxy resin, and wires are welded to the upper surfaces of the four piezoelectric sheets to form a whole excitation device;

[0084] (14) Wire 7 is connected to the upper surface of the piezoelectric piece, and wire 8 is connected to the lower surface of the piezoelectric piece; piezoelectric piece 1 and piezoelectric piece 3 share an excitation voltage signal of channel 1 (or channel 2), wherein the upper surface of piezoelectric piece 1 is connected to the positive pole of the excitation voltage signal, and the lower surface is connected to the negative pole, and the upper surface of piezoelectric piece 3 is connected to the negative pole, and the lower surface is connected to the positive pole; piezoelectric piece 2 and piezoelectric piece 4 share an excitation voltage signal of channel 2 (or channel 1), wherein the upper surface of piezoelectric piece 2 is connected to the positive pole, and the lower surface is connected to the negative pole, and the upper surface of piezoelectric piece 4 is connected to the negative pole, and the lower surface is connected to the positive pole; both channel 1 and channel 2 of the excitation voltage signal use multi-cycle sinusoidal pulse voltage signals, and there is a phase difference of π / 2 between the two channels with respect to the center frequency.

[0085] Figure 4 Schematic diagram of a sinusoidal pulse excitation voltage signal channel 1 and channel 2, the center frequency is 30 kHz, and there is a phase difference of π / 2 between channel 1 and channel 2 with respect to the center frequency 30 kHz;

[0086] Figure 5 This is a rendering of the device of this embodiment, showing the calculation result of an example when the central frequency of the excitation signal is 30 kHz, and the out-of-plane displacement field presents a clockwise spiral distribution.

[0087] In summary, the present invention connects the piezoelectric vibration array to the dual-channel voltage signal according to the wiring method described, and finally generates a spin plate wave in the plate through the connection fixing part and the mounting base. It can be used for related experiments and practical applications of spin plate waves, and provides a basis for related experimental research. In addition, the preparation process of the present invention is simple and convenient, and can ensure the reliability of the device.

Claims

1. A method for preparing a dual-channel controlled spin plate wave source excitation device, characterized in that: The spin plate wave source excitation device comprises a base (6), on which a piezoelectric vibration component array is mounted, the piezoelectric vibration component array is connected to an external dual-channel voltage excitation source, the piezoelectric vibration component array comprises four piezoelectric sheets (1) to (4) arranged in a square matrix, wherein two piezoelectric sheets at a diagonal position in the piezoelectric vibration component array are connected to one channel of the dual-channel voltage excitation source, and two piezoelectric sheets at another diagonal position in the piezoelectric vibration component array are connected to another channel of the dual-channel voltage excitation source; The above preparation method comprises the following steps: S1. According to the wavelength data corresponding to the frequency band required by the spin plate wave source, the sizes of the four piezoelectric sheets in the piezoelectric vibration component array are selected; S2, determining the distance between two adjacent piezoelectric sheets according to the wavelength data corresponding to the frequency band required by the spin plate wave source and the size data of the piezoelectric sheets; S3, fix a piece of double-sided tape to the work surface, determine the size according to step S1 and step S2, and mark four positions for fixing the piezoelectric piece on the double-sided tape; S4. Fix a wire at each of the four locations marked on the double-sided tape; S5. Apply a thin layer of epoxy resin to the four locations marked on the double-sided tape. S6, placing the four piezoelectric sheets in the marked positions in sequence, and pressing them so that the four piezoelectric sheets are flat and initially fixed in the predetermined positions; S7, detecting whether each wire is connected to the lower surface of the corresponding piezoelectric sheet, if not, returning to execute steps S4 to S6 until each wire is connected to the lower surface of the corresponding piezoelectric sheet; S8, checking whether each wire is connected to the lower surfaces of the other three piezoelectric sheets that do not correspond to each other, and if so, returning to steps S4 to S7 until each wire is not connected to the lower surfaces of the other three piezoelectric sheets that do not correspond to each other; S9. When the piezoelectric sheet and the wire are initially fixed but the epoxy resin is not completely cured, remove the double-sided tape; S10, fix the double-sided tape on the workbench again, apply a thin layer of epoxy resin, and then fix the four piezoelectric sheets and wires that have been initially fixed into the epoxy resin and press to fix; S11, executing steps S7-S8 again, if each wire is well connected with the corresponding piezoelectric sheet, and each wire is not connected with the lower surfaces of the other three piezoelectric sheets, then place and cure for 2 to 3 hours to obtain a piezoelectric vibration component; S12, clean up the double-sided tape, check the cured piezoelectric vibration component, and check whether the wire and the bottom of the piezoelectric vibration component are insulated. If not, return to step S10 and add a layer of epoxy resin under the component; if it is insulated, execute step S13; S13, fixing the piezoelectric vibration assembly to a metal sheet using epoxy resin, and welding wires to the upper surfaces of the four piezoelectric sheets to form an integral excitation device; S14, connecting the four piezoelectric sheets to an external dual-channel voltage excitation source: two piezoelectric sheets located at a diagonal position in the piezoelectric vibration component array share an excitation voltage signal of one channel, wherein the upper surface of one piezoelectric sheet is connected to a positive electrode and the lower surface is connected to a negative electrode, and the upper surface of the other piezoelectric sheet is connected to a negative electrode and the lower surface is connected to a positive electrode; Two piezoelectric sheets at another diagonal position in the piezoelectric vibration component array share an excitation voltage signal of another channel, wherein the upper surface of one piezoelectric sheet is connected to the positive electrode and the lower surface is connected to the negative electrode, and the upper surface of the other piezoelectric sheet is connected to the negative electrode and the lower surface is connected to the positive electrode; The two channels of the dual-channel voltage excitation source both output multi-cycle sinusoidal pulse voltage signals, and there is a phase difference of π / 2 between the two channels with respect to the center frequency.

2. The method for preparing a dual-channel controlled spin plate wave source excitation device according to claim 1, characterized in that: The four piezoelectric sheets (1) to (4) in the piezoelectric vibration component array have the same size, material and polarization direction. The piezoelectric sheets are specifically circular sheets, circular rings or square sheets.

3. The method for preparing a dual-channel controlled spin plate wave source excitation device according to claim 1, characterized in that: The piezoelectric sheet is mounted on a base (6) via a connecting fixture (5).

4. The method for preparing a dual-channel controlled spin plate wave source excitation device according to claim 3, characterized in that: The connecting and fixing member (5) is specifically epoxy resin.

5. The method for preparing a dual-channel controlled spin plate wave source excitation device according to claim 1, characterized in that: The base (6) is specifically a metal sheet.

6. The method for preparing a dual-channel controlled spin plate wave source excitation device according to claim 1, characterized in that: The upper surface and the lower surface of the piezoelectric sheet are respectively connected with a first wire (7) and a second wire (8), and the first wire (7) and the second wire (8) are respectively connected to the positive electrode or the negative electrode of one channel in a dual-channel voltage excitation source.

7. The method for preparing a dual-channel controlled spin plate wave source excitation device according to claim 6, characterized in that: Of the two piezoelectric sheets at a diagonal position in the piezoelectric vibration component array, the upper surface of one piezoelectric sheet is connected to the positive electrode and the lower surface is connected to the negative electrode, while the upper surface of the other piezoelectric sheet is connected to the negative electrode and the lower surface is connected to the positive electrode.

8. The method for preparing a dual-channel controlled spin plate wave source excitation device according to claim 1, characterized in that: Both channels of the dual-channel voltage excitation source output multi-cycle sinusoidal pulse voltage signals, and there is a phase difference of π / 2 between the two channels with respect to the center frequency.

9. The method for preparing a dual-channel controlled spin plate wave source excitation device according to claim 1, characterized in that: The size of the piezoelectric sheet and the distance between two adjacent piezoelectric sheets are determined according to the wavelength corresponding to the set working frequency of the spin plate wave source.

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