Piezoelectric fluid pump

Abstract

The present invention relates to the technical field of piezoelectric pumps, and in particular to a piezoelectric fluid pump, comprising a fluid excitation unit and at least one opposing plate; the fluid excitation unit comprises a piezoelectric sheet, a substrate, a spacer and a diaphragm, and the piezoelectric sheet and the substrate constitute an actuator; a pump chamber is formed between the opposing plate and the diaphragm; at least two holes connected to the pump chamber are penetrated in the area of ​​the opposing plate opposite to the diaphragm, and the holes are inlets or outlets, wherein at least one hole is an inlet, and another at least one hole is an outlet, and at least one hole is provided with a one-way valve; the piezoelectric fluid pump of the present invention uses a diaphragm as an excitation source for exciting the fluid in the pump chamber to produce pressure changes, and the diaphragm is fixedly connected to the actuator through the spacer. Under this structure, the extremely small vibration displacement of the actuator can cause the diaphragm to produce several times or even dozens of times the vibration displacement of the actuator, thereby greatly improving the volume change of the pump chamber during operation, thereby greatly improving the output flow rate.

Description

Technical Field

[0001] The present invention relates to the technical field of piezoelectric pumps, and in particular to a piezoelectric fluid pump. Background Art

[0002] In recent years, as 3C terminal products have continued to develop rapidly towards intelligence and thinness, the heat load of internal electronic devices has gradually increased, and efficient heat dissipation has become a hot topic of research. Placing a microfluidic control device with a piezoelectric transducer as an actuator in the internal space of a terminal product as a heat dissipation device is believed to be able to generate greater thermal benefits, but this also puts forward new requirements for the structural performance of such heat dissipation devices themselves.

[0003] The fluid pump disclosed in the Chinese patent with publication number CN102597520A declares a gas generating device using a piezoelectric transducer as an actuator. The actuator is usually designed to work in a first-order resonance mode or a third-order resonance mode. Even if the actuator is small, it can obtain sufficient amplitude during the bending vibration process, thereby ensuring the output performance of the fluid pump; the blower disclosed in the Chinese patent with publication number CN108317093A similarly declares a gas generating device using a resonant piezoelectric transducer as an actuator; in addition, in order to further improve the structural compactness and miniaturization of the piezoelectric-driven gas generating device, in the process of technological iteration, there are also a vertically supported micro piezoelectric pump disclosed in the Chinese patent with publication number CN209838655U and a staggered support structure and gas control device of a piezoelectric micropump disclosed in the Chinese patent with patent number CN213063904U.

[0004] In the above patent documents, the gas generation principle is the same or similar, and the basic components of the gas generating device, or fluid pump, or blower, or micro piezoelectric pump or fluid control device are also the same or similar. At least they all include a piezoelectric actuator, a deformable flexible plate (or resonance plate, flexible plate, thin-walled portion, etc.) at a central position and nearby position relative to the actuator with a gap, and a side wall that forms an excitation cavity together with the actuator and the flexible plate. The actuator is elastically supported on the side wall by a support portion, and a drainage hole for fluid to pass through is also provided on the flexible plate relative to the central area of ​​the actuator. The actuator is plane-supported on the side wall, or the actuator is vertically supported on the side wall. The actuator vibrates under external excitation. Along with the vibration of the actuator, the gas in the gap between the actuator and the flexible plate produces pressure changes, thereby causing the flexible plate centered on the drainage hole to resonate. Therefore, the vibration amplitude can be substantially increased, thereby increasing the flow rate.

[0005] However, in the above structure, the vibration energy of the actuator is transmitted to the flexible plate through the change of gas pressure in the gap, thereby forcing the flexible plate to resonate. Due to the existence of pneumatic damping, there is a large loss of vibration energy transmitted through fluid-solid coupling, and the energy transfer efficiency is not high. At the same time, the effective working space of the above resonance system is mainly concentrated in the area of ​​the gap opposite to the central large amplitude of the piezoelectric actuator and the flexible plate, while the vibration energy of the area outside the central large amplitude area of ​​the piezoelectric actuator and the flexible plate is not effectively utilized, resulting in low overall energy utilization. The gap volume change under this structure is limited, and the flow output performance is poor. When used as a heat dissipation device, it cannot meet the use requirements. Summary of the invention

[0006] The technical problem to be solved by the present invention is: in order to solve the deficiencies in the prior art, a piezoelectric fluid pump is provided to solve the problems of low energy transfer and utilization efficiency and poor flow output performance in the prior art.

[0007] The technical solution adopted by the present invention to solve the technical problem is: a piezoelectric fluid pump, including a fluid excitation unit and at least one opposing plate;

[0008] The fluid excitation unit comprises a piezoelectric sheet, a substrate, a spacer and a diaphragm. At least one piezoelectric sheet is bonded to one side or both sides of the substrate in the thickness direction. The piezoelectric sheet is bonded to the substrate to form an actuator. The piezoelectric sheet causes the actuator to vibrate under the stimulation of an electrical signal. The actuator comprises a first main surface and a second main surface which are arranged opposite to each other in the thickness direction. The first main surface and / or the second main surface are bonded with the spacer. The spacer is connected to the actuator at one end of the actuator close to the end of the actuator. The spacer and the actuator form a groove having an opening at one end facing away from the actuator. The diaphragm is fixedly connected to the end of the spacer facing away from the actuator and covers the opening of the groove, so that an excitation cavity is formed between the actuator, the groove and the diaphragm.

[0009] The opposing plate is arranged at a distance from the actuator on the side of the diaphragm, so that a pump cavity is formed between the opposing plate and the diaphragm; at least two holes communicating with the pump cavity are penetrated in the area of ​​the opposing plate opposite to the diaphragm;

[0010] When the actuator vibrates, the diaphragm is caused to vibrate, and at least one of the holes is provided in a region of the opposing plate that is opposite to the antinode position of the diaphragm vibration and the region adjacent to the antinode position;

[0011] The hole portion is an inlet or an outlet, wherein at least one hole portion is an inlet, and at least one hole portion is an outlet, and at least one hole portion is provided with a one-way valve;

[0012] At least one hole portion provided with a one-way valve is disposed in a region of the opposing plate that is opposite to an antinode position of diaphragm vibration and a region adjacent to the antinode position;

[0013] When the hole portion with a one-way valve is used as the inlet, the one-way valve at the inlet is used to limit the fluid from the inlet where the one-way valve is located to the pump chamber; and when the hole portion with a one-way valve is used as the outlet, the one-way valve at the outlet is used to limit the fluid from the pump chamber to the outlet where the one-way valve is located. When the diaphragm vibrates, the area corresponding to each hole portion in the pump chamber is stimulated to produce a greater gas pressure change than the area corresponding to the pump chamber at the peripheral edge of the diaphragm, so that the fluid flows into the pump chamber from the inlet and flows out from the pump chamber through the outlet. The area of ​​the pump chamber corresponding to the peripheral edge of the diaphragm is the edge area.

[0014] Furthermore, the holes are all arranged in the area of ​​the opposing plate that is opposite to the antinode position of the diaphragm vibration and the area adjacent to the antinode position;

[0015] Alternatively, the holes are respectively provided in the area of ​​the opposing plate that faces the antinode position and the adjacent area of ​​the antinode position of the diaphragm vibration and the area of ​​the opposing plate that faces the node position and the adjacent area of ​​the node position of the diaphragm vibration.

[0016] Further, the diaphragm vibration has only one antinode, at least one hole portion provided with the one-way valve is used as the first hole, and the remaining hole portions are used as the second hole, and the second hole is not provided with a one-way valve; the first hole is arranged in an area of ​​the opposing plate opposite to the antinode position of the diaphragm vibration and an area adjacent to the antinode position; the second hole is arranged in an area of ​​the opposing plate opposite to the node position of the diaphragm vibration and an area adjacent to the node position;

[0017] One of the first hole and the second hole is an inlet, and the other is an outlet.

[0018] Further, the diaphragm vibration has only one antinode, the hole portions are all provided with a one-way valve, at least one hole portion provided with the one-way valve serves as a first hole, and the remaining hole portions serve as second holes, the one-way valve disposed in the first hole and the one-way valve disposed in the second hole restrict the flow of fluid in opposite directions, the first hole is disposed in an area of ​​the opposing plate that is opposite to the antinode position of the diaphragm vibration and an area adjacent to the antinode position; the second hole is disposed in an area of ​​the opposing plate that is opposite to the node position of the diaphragm vibration and an area adjacent to the node position;

[0019] One of the first hole and the second hole is an inlet, and the other is an outlet.

[0020] Further, the diaphragm vibration has only one antinode, and the hole portions are all provided with a one-way valve, wherein at least one hole portion provided with the one-way valve serves as a first hole, and the remaining hole portions serve as second holes, and the one-way valve disposed in the first hole and the one-way valve disposed in the second hole restrict the flow of fluid in opposite directions, and the first hole and the second hole are both disposed in an area of ​​the opposing plate opposite to the antinode position of the diaphragm vibration and an area adjacent to the antinode position;

[0021] One of the first hole and the second hole is an inlet, and the other is an outlet.

[0022] Further, the diaphragm vibration has at least two antinodes;

[0023] At least one hole portion provided with the one-way valve is used as a first hole, and the remaining hole portions are used as second holes, the second holes are not provided with a one-way valve, the first hole is provided in an area of ​​the opposing plate that is opposite to at least one antinode position of the diaphragm vibration and an area adjacent to the antinode position; the second hole is provided in an area of ​​the opposing plate that is opposite to a node position of the diaphragm vibration and an area adjacent to the node position;

[0024] One of the first hole and the second hole is an inlet, and the other is an outlet.

[0025] Further, the diaphragm vibration has at least two antinodes, the hole portions are all provided with a one-way valve, at least one hole portion provided with the one-way valve is used as a first hole, and the remaining hole portions are used as second holes, the first hole is provided in an area of ​​the opposing plate opposite to at least one antinode position of the diaphragm vibration and an area adjacent to the antinode position, the second hole is provided in an area of ​​the opposing plate opposite to a node position of the diaphragm vibration and an area adjacent to the node position, and the one-way valve provided in the first hole and the one-way valve provided in the second hole restrict the flow of fluid in opposite directions;

[0026] One of the first hole and the second hole is an inlet, and the other is an outlet.

[0027] Further, the diaphragm vibration has at least two antinodes;

[0028] At least one hole portion provided with the one-way valve is used as a first hole, and the remaining hole portions are used as second holes, the second hole is not provided with a one-way valve, and the first hole and the second hole are respectively provided in the area of ​​the opposing plate opposite to at least one antinode position of the diaphragm vibration and the adjacent area of ​​the antinode position;

[0029] One of the first hole and the second hole is an inlet, and the other is an outlet.

[0030] Further, the diaphragm vibration has at least two antinodes;

[0031] The hole portions are all provided with a one-way valve, at least one hole portion provided with the one-way valve is used as a first hole, and the other hole portions are used as second holes, the first hole and the second hole are respectively provided in the area of ​​the opposing plate opposite to at least one antinode position and the adjacent area of ​​the antinode position of the diaphragm vibration; the one-way valve provided in the first hole and the one-way valve provided in the second hole restrict the flow of fluid in opposite directions;

[0032] One of the first hole and the second hole is an inlet, and the other is an outlet.

[0033] Furthermore, the spacer is an annular structure, the inner peripheral wall of the spacer and the actuator enclose an annular groove, and the end of the spacer away from the actuator is fully or partially engaged with the diaphragm on an annular path around the groove.

[0034] Furthermore, the spacer portion has a plurality of spacers, each of which is joined to the first main surface or the second main surface, and the plurality of spacers are distributed circumferentially around the excitation cavity to form the groove portion with the actuator, and one end of the spacer facing away from the actuator is fully or partially joined to the diaphragm.

[0035] Furthermore, the piezoelectric ceramic sheet is in a ring-shaped structure with a hole running through the center, and the hole is arranged opposite to the excitation cavity.

[0036] Furthermore, the diaphragm is made of a polymer material, or a composite material of a polymer material and a metal material.

[0037] Furthermore, it also includes a frame plate and an elastic connecting part, the frame plate surrounds the actuator, one end of the connecting part is connected to the frame plate, and the other end is connected to the actuator, and the outer periphery of the side surface of the opposing plate opposite to the diaphragm is fixed to the frame plate.

[0038] The actuator is connected to the opposing plate. Regarding the connection structure between the actuator and the opposing plate, the following solutions can be adopted:

[0039] In one embodiment, the frame plate surrounds the actuator with a gap therebetween except for the connection portion.

[0040] Furthermore, the actuator has at least one connecting boss protruding from one side surface of the opposing plate and located outside the spacer portion, and the opposing plate has a notch in the area opposite to the connecting boss, an elastic support portion is formed in the notch, and the connecting boss is fixedly connected to the elastic support portion opposite to it.

[0041] Secondly, at least one connecting boss located outside the spacer protrudes from one side surface of the actuator facing the opposing plate, the connecting boss is elastic, and the connecting boss is fixedly connected to the side of the opposing plate close to the base plate.

[0042] Thirdly, it further comprises a frame portion and a support portion, wherein the frame portion surrounds the actuator and has a height protruding from the actuator in the thickness direction of the substrate;

[0043] The supporting portion includes a cantilever portion and a holding portion, wherein the holding portion is engaged at a node position of vibration of the actuator, and the holding portion is arranged on a side of the actuator away from the opposing plate. One end of the cantilever portion is connected to a surface of the holding portion away from the actuator, and the other end is connected to a side of the frame portion away from the opposing plate. The frame portion is fixedly connected to the opposing plate on a side facing the opposing plate.

[0044] The beneficial effects of the present invention are:

[0045] 1) The piezoelectric fluid pump of the present invention uses a diaphragm as an excitation source to excite the fluid in the pump chamber to produce pressure changes. The diaphragm is fixedly connected to the actuator through a spacer. Under this structure, the extremely small vibration displacement of the actuator can cause the diaphragm to produce a displacement several times or even dozens of times the vibration displacement of the actuator, thereby greatly increasing the volume change of the pump chamber between the diaphragm and the opposing plate during operation, thereby greatly increasing the output flow rate;

[0046] 2) In the piezoelectric fluid pump of the present invention, the actuator generates vibration under external excitation and transmits the vibration energy to the diaphragm, thereby causing the diaphragm to vibrate. Since the vibration displacement of the diaphragm is several times or even dozens of times greater than the vibration displacement of the actuator, when the diaphragm is used as an excitation source to excite the gas in the excitation chamber to generate pressure changes, it is not necessary to set the diaphragm to work in the first-order resonance mode, the third-order resonance mode, or a higher-order centrosymmetric resonance mode. In a non-centrosymmetric resonance mode, for example, the second-order resonance mode or the fourth-order resonance mode, the effective working space of the gap between the diaphragm and the opposing plate is no longer mainly concentrated in the central area of ​​the diaphragm, but extends to a larger area than the central area, and the utilization rate of the vibration energy is higher;

[0047] 3) In the piezoelectric fluid pump of the present invention, the diaphragm is fixedly connected to the actuator through the spacer, and the vibration of the actuator causes the diaphragm to vibrate, and this process is accompanied by the transfer of energy. The vibration energy generated by the actuator under the excitation of the external electrical signal, on the one hand, drives the fluid in the excitation chamber to produce pressure changes when the actuator vibrates, thereby causing the diaphragm to vibrate and transfer the energy to the diaphragm. More importantly, the energy is directly transferred to the diaphragm through the mechanical coupling formed by the actuator and the diaphragm. Compared with the prior art that only relies on the fluid to transfer vibration energy, the energy transfer efficiency is higher. Under the same excitation conditions, it can cause the diaphragm to produce a larger amplitude to achieve a higher flow output; under the same amplitude requirement, it can reduce the input power of the actuator, reduce heat, and improve energy utilization, product stability and service life.

[0048] Other features and advantages of the present application will become apparent from the following detailed description of exemplary embodiments of the present application with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0049] The present invention is further described below in conjunction with the accompanying drawings and embodiments.

[0050] Figure 1 It is a schematic diagram of the structure of the groove formed by the spacer plate and the base plate in the present invention;

[0051] Figure 2 It is a schematic diagram of the structure in which the spacer and the piezoelectric sheet in the present invention are arranged on the same side surface of the substrate in the thickness direction;

[0052] Figure 3 A schematic diagram of a structure in which both main surfaces of the actuator of the present invention are provided with spacers combined with a substrate, and a piezoelectric sheet is provided on any one side surface of the substrate in the thickness direction;

[0053] Figure 4 It is a structural schematic diagram of the actuator of the present invention in which piezoelectric sheets and spacers are provided on both main surfaces of the actuator, and the spacers are bonded to the piezoelectric sheets;

[0054] Figure 5 A schematic diagram of a structure in which spacers are provided on both main surfaces of the actuator of the present invention, and the spacers on one side are bonded to the piezoelectric sheet, and the spacers on the other side are bonded to the substrate;

[0055] Figure 6 The diaphragm in Example 1 vibrates in a first-order resonance mode with central symmetry, and a first hole and a second hole are arranged on the opposing plates;

[0056] Figure 7 for Figure 6 An exploded diagram of a piezoelectric process pump;

[0057] Figure 8 for Figure 6 An exploded schematic diagram of a piezoelectric process pump from another perspective;

[0058] Fig. 9 It is a schematic diagram of the pump chamber sucking fluid during operation;

[0059] Fig.10 It is a schematic diagram of the pump chamber discharging fluid during operation;

[0060] Fig.11 It is a schematic diagram of the diaphragm in Example 1 vibrating in a centrally symmetrical first-order resonance mode, and the first hole and the second hole are both provided with a one-way valve;

[0061] Fig.12 The diaphragm in Example 1 vibrates in a first-order resonance mode with a central symmetry, and the opposing plate has at least two holes with one-way valves, both of which are arranged in the area of ​​the opposing plate opposite to the antinode position of the diaphragm vibration and the adjacent area of ​​the antinode position;

[0062] Fig.13 It is a schematic diagram of the diaphragm in Example 1 vibrating in a centrally symmetrical third-order resonance mode, with the first hole being arranged at an antinode position and the second hole without a one-way valve being arranged at a node position;

[0063] Fig.14 for Fig.13 An exploded diagram of a piezoelectric process pump;

[0064] Fig.15 for Fig.13 An exploded schematic diagram of a piezoelectric process pump from another perspective;

[0065] Fig.16 It is a schematic diagram of the diaphragm in Example 1 vibrating in a centrally symmetrical third-order resonance mode, with the first hole being arranged at an antinode position and the second hole with a one-way valve being arranged at a node position;

[0066] Fig.17 The diaphragm in Example 1 vibrates in a third-order resonance mode with a central symmetry, and the opposing plate has a hole portion with a valve and a hole portion without a valve disposed in an area of ​​the opposing plate opposite to at least two antinode position areas in a vibration direction opposite to the vibration direction of the diaphragm;

[0067] Fig.18 The diaphragm in Example 1 vibrates in a third-order resonance mode with a central symmetry, and the vibration directions of the antinode positions of the diaphragm vibration relative to the first hole and the second hole are the same;

[0068] Fig.19 It is a schematic structural diagram of the piezoelectric process pump in the second-order subresonance mode in which the diaphragm is centrally symmetrical in Example 1;

[0069] Fig. 20 It is a bottom-up structural schematic diagram of the diaphragm in Example 1, which is convexly deformed in one direction under the second-order subresonance mode with central symmetry;

[0070] Fig.21 It is a bottom-up structural schematic diagram of the diaphragm in Example 1 in a second-order subresonance mode in which the diaphragm is convexly deformed in another direction under a centrally symmetrical mode;

[0071] Fig. 22 It is a bottom view schematic diagram of the opposing plate when the diaphragm in Example 1 is in a centrally symmetrical second-order resonant mode;

[0072] Fig.23 It is a bottom-up structural schematic diagram of the diaphragm in Example 1, which is convexly deformed in one direction under the fourth-order resonance mode with centrosymmetry;

[0073] Fig.24 It is a bottom-up structural schematic diagram of the diaphragm in Example 1, which is convexly deformed in another direction under the fourth-order resonance mode with centrosymmetry;

[0074] Fig.25 It is a bottom view schematic diagram of the opposing plate when the diaphragm in Example 1 is in a fourth-order resonance mode with centrosymmetry;

[0075] Fig.26 It is a schematic diagram of a bottom-up structure of a rectangular diaphragm in Example 1 that is convexly deformed in one direction under a third-order resonance mode when both sides of the short sides are fixed;

[0076] Fig. 27 It is a schematic diagram of the bottom-up structure of the rectangular diaphragm in Example 1, which is convexly deformed in another direction under the third-order resonance mode when both sides of the short sides are fixed;

[0077] Fig.28 It is a bottom-up structural schematic diagram of the rectangular diaphragm in Example 1, which is convexly deformed in one direction under the second-order subresonance mode when both the short sides and the long sides are fixed;

[0078] Fig.29 It is a schematic diagram of a bottom-up structure of the rectangular diaphragm in Example 1 that is convexly deformed in one direction under a higher-order resonance mode when both short sides and long sides are fixed;

[0079] Fig.30 The schematic diagram of the structure of the spacer in Example 2 is a plurality of spacers arranged at intervals and evenly distributed in a ring shape;

[0080] Fig.31 is a schematic diagram of the piezoelectric fluid pump in Example 3;

[0081] Fig.32A schematic diagram of the structure of a piezoelectric fluid pump having a connecting portion with a continuous annular thin plate structure in Example 4

[0082] Fig.33 It is a top view schematic diagram of the connecting portion of the annular thin plate structure type connecting the frame plate and the base plate in Example 4;

[0083] Fig.34 is a schematic diagram of a piezoelectric fluid pump having a connecting portion including a plurality of discretely arranged elastic connecting beams in Example 4;

[0084] Fig.35 It is a top view schematic diagram of a connecting portion including a plurality of discretely arranged elastic connecting beams connecting a frame plate and a base plate in Example 4;

[0085] Fig.36 It is a structural schematic diagram of a piezoelectric fluid pump in which a substrate is elastically supported on an opposing plate in a vertical direction in Example 5;

[0086] Fig.37 It is a partial exploded schematic diagram of the piezoelectric fluid pump in Example 5 including a substrate and an opposing plate;

[0087] Fig.38 A partial exploded schematic diagram of another perspective of the piezoelectric fluid pump including a substrate and an opposing plate in Example 5;

[0088] Fig.39 Schematic diagram of the structure of the piezoelectric fluid pump having a frame portion and a support portion in Example 6.

[0089] In the figure: 1, piezoelectric sheet, 1-1, cavity;

[0090] 2. Substrate;

[0091] 3. Actuator, 3-1. First main surface, 3-2. Second main surface;

[0092] 4, spacer, 4-1, groove, 41, spacer;

[0093] 5. Diaphragm;

[0094] 6. Excitation chamber;

[0095] 7. Opposing plate, 7-1. Hole portion; 7-11. First hole; 7-12. Second hole; 7-2. Notch; 7-3. Elastic support portion;

[0096] 8. Pump chamber; 8-1. Edge area;

[0097] 9. Check valve;

[0098] 10. frame plate, 10-1. connecting part;

[0099] 11. Connecting boss;

[0100] 12. Frame portion, 12-1. Support portion, 12-11. Cantilever portion, 12-12. Holding portion.

[0101] A, antinode position, A1, central antinode, A2, annular antinode;

[0102] B. Node location. DETAILED DESCRIPTION

[0103] The present invention will now be described in further detail with reference to the accompanying drawings. These drawings are simplified schematic diagrams that only illustrate the basic structure of the present invention in a schematic manner, and therefore only show the components related to the present invention, and directions and references (e.g., up, down, left, right, etc.) may only be used to help describe the features in the drawings. Therefore, the following specific embodiments are not to be taken in a limiting sense, and the scope of the subject matter claimed is limited only by the attached claims and their equivalents.

[0104] Example 1

[0105] A piezoelectric fluid pump comprises a fluid excitation unit and an opposing plate 7;

[0106] The fluid excitation unit comprises a piezoelectric sheet 1, a substrate 2, a spacer 4 and a diaphragm 5. At least one piezoelectric sheet 1 is bonded to one or both sides of the substrate 2 in the thickness direction. The piezoelectric sheet 1 and the substrate 2 constitute an actuator 3. The piezoelectric sheet 1 causes the actuator 3 to vibrate under the excitation of an electrical signal.

[0107] The substrate 2 may be, but is not limited to, circular, rectangular, polygonal or elliptical, etc. In this embodiment, the substrate 2 is in the shape of a circular plate as an example. A single piezoelectric film 1 can be bonded to any side surface of the substrate 2 in the thickness direction to form a piezoelectric unimorph actuator 3; or two piezoelectric films 1 are respectively arranged on the two side surfaces of the substrate 2 in the thickness direction to form a piezoelectric dual-chip actuator 3; or multiple piezoelectric films 1 are arranged on the same side surface of the substrate 2 in the thickness direction to form a composite multilayer piezoelectric actuator 3, etc. The piezoelectric film 1 causes the actuator 3 to vibrate under the excitation of an external periodic electrical signal.

[0108] The actuator 3 has a first main surface 3-1 and a second main surface 3-2 that are relatively arranged in the thickness direction. The first main surface 3-1 and / or the second main surface 3-2 are joined with a spacer 4. The spacer 4 is connected to the actuator 3 near one end of the actuator 3, and the spacer 4 and the actuator 3 form a groove 4-1 with an opening at the end facing away from the actuator 3.

[0109] Specifically:

[0110] The spacer 4 can be bonded to one side or both sides of the substrate 2 constituting the actuator 3 in the thickness direction. At this time, it is not difficult to understand that the spacer 4 can be bonded to either one side of the substrate 2 in the thickness direction or the other side of the substrate 2 in the thickness direction. Figure 1 and Figure 2 As shown, of course, when there are multiple spacers 4 at the same time, for example, the piezoelectric fluid pump of the present application can have a bidirectional working function. In this case, the spacers 4 need to be provided on both main surfaces of the actuator 3. The spacers 4 can be provided on both side surfaces of the substrate 2 in the thickness direction, such as Figure 3 As shown; under this structure, when the spacer 4 and the piezoelectric sheet 1 are arranged on the same side surface of the substrate 2 in the thickness direction, the piezoelectric sheet 1 is located in the groove 4-1 of the spacer 4, and at the same time, the spacer 4 has a height protruding from the surface of the piezoelectric sheet 1, as shown in FIG. Figure 2 and 3 When the spacer 4 and the piezoelectric sheet 1 are respectively arranged on both side surfaces of the substrate 2 in the thickness direction, this limitation is not applied, and the bonding between the spacer 4 and the substrate 2 can be bonding or integrally formed.

[0111] In addition, the spacer 4 can also be joined to the side surface of the piezoelectric sheet 1 constituting the actuator 3 that is away from the actuator 3. Under this structure, it is not difficult to understand that when the actuator 3 constitutes the above piezoelectric single-chip actuator 3, the spacer 4 can be joined to the side surface of the piezoelectric sheet 1 constituting the piezoelectric single-chip actuator 3 that is away from the substrate 2; when the actuator 3 constitutes the above piezoelectric dual-chip actuator 3, the spacer 4 can be joined to the side surface of the piezoelectric sheet 1 on either side of the piezoelectric dual-chip actuator 3 that is away from the substrate 2. Of course, when there are multiple spacers 4 at the same time, for example, the piezoelectric fluid pump of the present application can have a bidirectional working function. At this time, the first main surface 3-1 and the second main surface 3-2 of the actuator 3 need to be provided with a spacer 4. The spacer 4 can be respectively provided on the side surfaces of the piezoelectric sheets 1 on both sides of the piezoelectric dual-chip actuator 3 that are away from the substrate 2, such as Figure 4 shown.

[0112] In addition, it is not difficult to understand that when there are multiple spacers 4 at the same time, the above-mentioned bonding methods of the spacers 4 can also be combined with each other. For example, the piezoelectric fluid pump of the present application can have a bidirectional working function. At this time, the first main surface 3-1 and the second main surface 3-2 of the actuator 3 both need to be provided with spacers 4, wherein there is a spacer 4 bonded to the surface of the side of the piezoelectric sheet 1 constituting the actuator 3 away from the actuator 3, and there is another spacer 4 bonded to the side of the substrate 2 away from the actuator 3, such as Figure 5 As shown, under this structure, the connection between the spacer 4 and the substrate 2 can be adhesively bonded or integrally formed.

[0113] Of course, the joining method of the spacer 4 is not limited to this. The joining method of the spacer 4 follows the principle that the end of the spacer 4 close to the actuator 3 is connected to the actuator 3, and the spacer 4 and the actuator 3 form a groove 4-1 with an opening at the end away from the actuator 3.

[0114] In this embodiment, the actuator 3 is constructed as a piezoelectric single-chip actuator 3, the spacer 4 is one, and the spacer 4 is bonded to the surface of the substrate 2 located on the side where the second main surface 3-2 of the actuator 3 is located, for easy understanding.

[0115] The spacer 4 is bonded to the surface of the substrate 2 located on the side where the second main surface 3-2 is located, and the end of the spacer 4 close to the substrate 2 is connected to the substrate 2, and the spacer 4 and the substrate 2 form a groove 4-1 with an opening at the end facing away from the substrate 2, such as Figure 1 As shown; the connection between the spacer 4 and the substrate 2 can be bonding or integrally formed, the spacer 4 is an annular structure, so that the inner peripheral wall of the spacer 4 itself encloses the groove portion 4-1,

[0116] One end of the spacer 4 close to the substrate 2 is joined to the surface of the substrate 2 on the side where the second main surface 3-2 is located, and the diaphragm 5 is connected to the end of the spacer 4 facing away from the substrate 2, so that the vibration of the actuator 3 can directly drive the spacer 4 and the diaphragm 5 to vibrate, so as to transfer the vibration energy to the diaphragm 5 through mechanical coupling.

[0117] The diaphragm 5 is connected to the end of the spacer 4 away from the actuator 3 and covers the opening of the groove 4-1, so that an excitation cavity 6 is formed between the substrate 2, the groove 4-1 and the diaphragm 5;

[0118] Thus, the diaphragm 5 is fixedly connected to the actuator 3 through the spacer 4, and the actuator 3 vibrates, causing the diaphragm 5 to vibrate, and this process is accompanied by energy transfer. The vibration energy generated by the actuator 3 under the excitation of the external electrical signal, on the one hand, drives the fluid in the excitation chamber 6 between the actuator 3 and the diaphragm 5 to produce pressure changes when the actuator 3 vibrates, thereby causing the diaphragm 5 to vibrate and transfer the energy to the diaphragm 5. More importantly, the energy is directly transferred to the diaphragm 5 through the mechanical coupling formed by the actuator 3 and the diaphragm 5. Compared with the prior art that only relies on the fluid to transfer vibration energy, the energy transfer efficiency is higher. Under the same excitation conditions, the diaphragm 5 can be caused to produce a larger amplitude to achieve a higher flow output; under the same amplitude requirement, the input power of the actuator 3 can be reduced, the heat generation can be reduced, and the energy utilization rate, product stability and service life can be improved.

[0119] An opposing plate 7 is provided on the side of the diaphragm 5 facing away from the actuator 3, so that a pump cavity 8 is formed between the opposing plate 7 and the diaphragm 5. Obviously, if the actuator 3 is provided with the spacing portion 4 and the diaphragm 5 only on the first main surface 3-1, then the actuator 3 is also provided with the opposing plate 7 on the side where the first main surface 3-1 is located, so as to form the pump cavity 8 located on the side where the first main surface 3-1 is located; if the actuator 3 is provided with the spacing portion 4 and the diaphragm 5 only on the second main surface 3-2, then the actuator 3 is also provided with the opposing plate 7 on the side where the second main surface 3-2 is located. An opposing plate 7 is arranged on the side to form a pump chamber 8 located on the side where the second main surface 3-2 is located; if the actuator 3 is provided with a spacer 4 and a diaphragm 5 on both the first main surface 3-1 and the second main surface 3-2, then the actuator 3 may also be provided with an opposing plate 7 respectively on the side where the first main surface 3-1 is located and the side where the second main surface 3-2 is located to form a pump chamber 8 located on the side where the first main surface 3-1 is located and a pump chamber 8 located on the side where the second main surface 3-2 is located, so that the piezoelectric fluid pump can have the function of bidirectional operation.

[0120] At least two holes 7-1 communicating with the pump chamber 8 are formed in the area of ​​the opposing plate 7 opposite to the diaphragm 5. When the actuator 3 vibrates, the diaphragm 5 is caused to vibrate. The holes 7-1 are arranged in the area of ​​the opposing plate 7 opposite to the antinode position A of the vibration of the diaphragm 5 and the adjacent area of ​​the antinode position A.

[0121] The hole portion 7-1 is an inlet or an outlet, wherein at least one hole portion 7-1 is an inlet, and at least one hole portion 7-1 is an outlet, and at least one hole portion 7-1 is provided with a one-way valve 9; the hole portion 7-1 having at least one one-way valve 9 is arranged in an area of ​​the opposing plate 7 that is opposite to the antinode position A of the vibration of the diaphragm 5 and an area adjacent to the antinode position A;

[0122] Preferably, the holes 7 - 1 are all disposed in the region of the opposing plate 7 that is opposite to the antinode position A of the vibration of the diaphragm 5 and the region adjacent to the antinode position A;

[0123] Alternatively, the holes 7 - 1 are provided in the area of ​​the opposing plate 7 that faces the antinode position A of the diaphragm 5 and the vicinity of the antinode position A and the area of ​​the opposing plate 7 that faces the node position B of the diaphragm 5 and the vicinity of the node position B.

[0124] When the hole portion 7-1 with a one-way valve 9 is used as an inlet, the one-way valve 9 at the inlet is used to limit the fluid from flowing from the inlet where the one-way valve 9 is located to the pump chamber 8; and when the hole portion 7-1 with a one-way valve 9 is used as an outlet, the one-way valve 9 at the outlet is used to limit the fluid from flowing from the pump chamber 8 to the outlet where the one-way valve 9 is located; when the diaphragm 5 vibrates, the area corresponding to each hole portion 7-1 in the pump chamber 8 is stimulated to produce a more drastic gas pressure change than the area corresponding to the pump chamber 8 at the peripheral edge of the diaphragm 5, so that the fluid flows into the pump chamber 8 from the inlet and flows out from the pump chamber 8 through the outlet; the area corresponding to the pump chamber 8 at the peripheral edge of the diaphragm 5 is the edge area 8-1.

[0125] The actuator 3 vibrates under external excitation and transmits the vibration energy to the diaphragm 5, thereby causing the diaphragm 5 to vibrate. The vibration of the diaphragm 5 causes pressure changes in the pump chamber 8; compared with the prior art, the gap between the diaphragm 5 and the opposing plate 7 constitutes the pump chamber 8. This structure uses the diaphragm 5 as an excitation source to excite the gas in the pump chamber 8 to produce pressure changes. The diaphragm 5 is fixedly connected to the actuator 3 through the spacer 4. Under this structure, the extremely small vibration displacement of the actuator 3 can cause the diaphragm 5 to produce a displacement that is several times or even dozens of times the vibration displacement of the piezoelectric actuator 3. In this way, the volume change of the pump chamber 8 during operation can be greatly increased, thereby greatly increasing the output flow rate.

[0126] The working process of the fluid pump includes an intake stroke and an exhaust stroke. Since the gas has flow inertia, the intake stroke and the exhaust stroke do not have a clear boundary, that is, when the fluid pump is in the intake stroke, exhaust is also carried out synchronously for a period of time. Similarly, when the fluid pump is in the exhaust stroke, intake is also carried out synchronously for a period of time. The intake stroke and exhaust stroke here represent the net inflow and net outflow of gas in the pump chamber 8. Since the holes 7-1 are all arranged relative to the diaphragm 5, within a certain height range of the pump chamber 8, the area corresponding to each hole 7-1 in the pump chamber 8 will definitely produce a greater gas pressure change than the area corresponding to the outer peripheral edge of the pump chamber 8 at the diaphragm 5. When the pump chamber 8 produces periodic volume changes, the gas is mainly inhaled and discharged from the hole 7-1 arranged relative to the diaphragm 5; the area corresponding to the outer peripheral edge of the diaphragm 5, that is, the edge area 8-1, of the pump chamber 8 is not necessarily locked; according to the different vibration modes of the diaphragm 5, the setting of the hole 7-1 includes but is not limited to the following forms:

[0127] First, the vibration of the diaphragm 5 has only one antinode. For example, when the diaphragm 5 vibrates in a first-order resonance mode that is centrally symmetrical, there is only one central antinode A1, and the vibration displacement at the central position of the diaphragm 5 is the largest.

[0128] At this time, at least one hole portion 7-1 provided with a one-way valve 9 may be used as the first hole 7-11, and the other hole portions 7-1 may be used as the second hole 7-12. The first hole 7-11 is provided in the area of ​​the opposing plate 7 opposite to the antinode position A of the vibration of the diaphragm 5 and the adjacent area of ​​the antinode position A. The adjacent area of ​​the antinode position A refers to the area close to the side of the antinode position A but not including the antinode position A in the interval between the node position B and the antinode position A of the vibration of the diaphragm 5; the second hole 7-12 is provided in the area of ​​the opposing plate 7 opposite to the node position B of the vibration of the diaphragm 5 and the adjacent area of ​​the node position B; the adjacent area of ​​the node position B refers to the area close to the side of the node position B but not including the node position B in the interval between the node position B and the antinode position A of the vibration of the diaphragm 5. The second hole 7-12 may be provided with a one-way valve 9 or not; one of the first hole 7-11 and the second hole 7-12 is an inlet, and the other is an outlet;

[0129] When the second hole 7-12 is not provided with a one-way valve 9, it is not important whether the one-way valve 9 in the first hole 7-11 restricts the fluid from flowing into the pump chamber 8 between the diaphragm 5 and the opposing plate 7 or restricts the fluid from flowing out of the pump chamber 8 between the diaphragm 5 and the opposing plate 7. Figure 6 to Figure 8 Assume that the one-way valve 9 in the first hole 7-11 is to limit the fluid from flowing into the pump chamber 8 between the diaphragm 5 and the opposing plate 7. At this time, the first hole 7-11 is used as an outlet and the second hole 7-12 is used as an inlet. The inhalation and discharge of gas are as follows: Figure 9-10 As shown; on the contrary, when the one-way valve 9 in the first hole 7-11 restricts the fluid from flowing out of the pump chamber 8 between the diaphragm 5 and the opposing plate 7, at this time, the first hole 7-11 serves as an inlet, and the second hole 7-12 serves as an outlet;

[0130] When the second hole 7-12 is provided with a one-way valve 9, the one-way valve 9 in the first hole 7-11 and the one-way valve 9 in the second hole 7-12 restrict the flow of the fluid in opposite directions. Assuming that the one-way valve 9 in the first hole 7-11 restricts the fluid from flowing into the pump chamber 8 between the diaphragm 5 and the opposing plate 7, the second hole 7-12 restricts the fluid from flowing out of the pump chamber 8 between the diaphragm 5 and the opposing plate 7. Fig.11 As shown;

[0131] Alternatively, each hole portion 7-1 is provided with a one-way valve 9, wherein at least one hole portion 7-1 provided with a one-way valve 9 serves as the first hole 7-11, and the remaining hole portions 7-1 serve as the second hole 7-12. The first hole 7-11 and the second hole 7-12 are both provided in the region of the opposing plate 7 that is opposite to the antinode position A of the vibration of the diaphragm 5 and the region adjacent to the antinode position A. Under this structure, the directions of the fluid flow restricted by the one-way valve 9 in the first hole 7-11 and the one-way valve 9 in the second hole 7-12 are opposite, as shown in FIG. Fig.12As shown; one of the first hole 7-11 and the second hole 7-12 is an inlet, and the other is an outlet.

[0132] Second, the diaphragm 5 vibrates with at least two antinodes. For example, the diaphragm 5 vibrates in a third-order resonance mode that is centrally symmetrical. The two antinode positions A may be a central antinode A1 and an annular antinode A2. The diaphragm 5 has a central antinode A1 at the central position, and an annular antinode A2 surrounding the central antinode A1 at a position further outward of the central antinode A1. The diaphragm 5 also has a node position B surrounding the central antinode A1 and located between the central antinode A1 and the annular antinode A2.

[0133] At this time, at least one hole portion 7-1 provided with a one-way valve 9 may be a first hole 7-11, and the remaining hole portions 7-1 may be second holes 7-12. The first hole 7-11 is provided in an area of ​​the opposing plate 7 that is opposite to at least one antinode position A of the vibration of the diaphragm 5 and an adjacent area of ​​the antinode position A, and the second hole 7-12 is provided in an area of ​​the opposing plate 7 that is opposite to a node position B of the vibration of the diaphragm 5 and an adjacent area of ​​the node position B. The second hole 7-12 may be provided with a one-way valve 9 or may not be provided with a one-way valve 9; one of the first hole 7-11 and the second hole 7-12 is an inlet, and the other is an outlet;

[0134] When the second hole 7-12 is not provided with a one-way valve 9, it is not important whether the one-way valve 9 in the first hole 7-11 restricts the fluid from flowing into the pump chamber 8 between the diaphragm 5 and the opposing plate 7 or restricts the fluid from flowing out of the pump chamber 8 between the diaphragm 5 and the opposing plate 7. Figure 13 to Figure 15 As shown;

[0135] When the second hole 7-12 is provided with a one-way valve 9, the directions of the fluid flow restricted by the one-way valve 9 in the first hole 7-11 and the one-way valve 9 in the second hole 7-12 must be opposite, such as Fig.16 shown.

[0136] It is also possible that the vibration of the diaphragm 5 has at least two antinodes;

[0137] At least one hole portion 7-1 provided with a one-way valve 9 is used as a first hole, and the remaining hole portions 7-1 are used as second holes 7-12. The first hole 7-11 and the second hole 7-12 are respectively arranged in the area of ​​the opposing plate 7 opposite to the antinode position A of the vibration of the diaphragm 5 and the adjacent area of ​​the antinode position A; here, the first hole 7-11 and the second hole 7-12 are respectively arranged in the area of ​​the opposing plate 7 opposite to the central antinode A1 of the vibration of the diaphragm 5 and the adjacent area of ​​the central antinode A1, or the first hole 7-11 and the second hole 7-12 are respectively arranged in the area of ​​the opposing plate 7 opposite to the vibration of the diaphragm 5 The first hole 7-11 and the second hole 7-12 are arranged in the area of ​​the opposing plate 7 opposite to the central antinode A1 of the vibrating diaphragm 5 and the adjacent area of ​​the central antinode A1, or, one of the first hole 7-11 and the second hole 7-12 is arranged in the area of ​​the opposing plate 7 opposite to the circular antinode A2 of the vibrating diaphragm 5 and the adjacent area of ​​the circular antinode A2; the second hole 7-12 may be provided with a one-way valve 9 or not; one of the first hole 7-11 and the second hole 7-12 is an inlet, and the other is an outlet.

[0138] When the second hole 7-12 is not provided with a one-way valve 9, it is not important whether the one-way valve 9 in the first hole 7-11 restricts the fluid from flowing into the pump chamber 8 between the diaphragm 5 and the opposing plate 7 or restricts the fluid from flowing out of the pump chamber 8 between the diaphragm 5 and the opposing plate 7. Fig.17 As shown;

[0139] When the second hole 7-12 is provided with a one-way valve 9, the directions of the fluid flow restricted by the one-way valve 9 in the first hole 7-11 and the one-way valve 9 in the second hole 7-12 must be opposite, such as Fig.18 shown.

[0140] The above-mentioned setting of the position of the hole 7-1 and the presence or absence of the one-way valve 9 in the hole 7-1 and the setting of the type of the one-way valve 9 follow the principle of enabling the gap between the diaphragm 5 and the opposing plate 7 to form a complete inflow and outflow process. Including but not limited to the several forms listed above; the one-way valve 9 can adopt any one-way valve 9 in the prior art.

[0141] The spacer 4 is an annular structure, and the inner peripheral wall of the spacer 4 encloses an annular groove 4-1, and the end of the spacer 4 away from the actuator 3 is fully or partially engaged with the diaphragm 5 on an annular path around the groove 4-1;

[0142] When the end of the annular spacer 4 facing away from the substrate 2 is completely engaged with the diaphragm 5 along the annular path around the groove 4-1:

[0143] In the first-order resonance mode, since there is only one central wave axis A1, its effective working space is mainly concentrated in the area of ​​the pump chamber 8 between the diaphragm 5 and the opposing plate 7 that is opposite to the central large amplitude of the diaphragm 5, while the vibration energy of the area outside the central large amplitude area of ​​the diaphragm 5 is not effectively utilized, resulting in low overall energy utilization. However, since the vibration displacement of the diaphragm 5 is significantly increased compared with the prior art, even the first-order resonance mode can obtain a higher output flow rate.

[0144] Of course, this situation can be effectively improved when the diaphragm 5 vibrates in a third-order resonance mode, or when the diaphragm 5 vibrates in a higher-order central symmetric resonance mode, because the diaphragm 5 in the high-order central symmetric resonance mode not only has a central wave trunk A1, but also has an annular wave trunk A2 surrounding the central wave trunk A1 at a position further outward from the central wave trunk A1, and the number of annular wave trunks A2 is related to the order of the resonance mode. The vibration of the diaphragm 5 also has wave nodes surrounding the central wave trunk A1, and the number of wave nodes is also related to the order of the resonance mode. Thereby, the effective working space of the pump chamber 8 between the diaphragm 5 and the opposing plate 7 is no longer mainly concentrated in the central area of ​​the diaphragm 5, but is expanded to a larger area than the central area. The vibration energy of the area outside the central large-amplitude area of ​​the diaphragm 5 can also be effectively utilized, and the utilization rate of the vibration energy is higher, so that during the working process, the pump chamber 8 between the diaphragm 5 and the opposing plate 7 can obtain a larger volume change, thereby increasing the output flow rate.

[0145] Of course, the vibration generated by the diaphragm 5 can be a vibration mode in which the center is symmetrical, or a vibration in a high-order resonance mode other than the central symmetrical vibration mode. For example, when the diaphragm 5 vibrates in a second-order resonance mode, it has two antinode positions A in which the axis is symmetrically distributed and a node position B located between the antinode positions A. Figure 19 to Figure 22 As shown in the figure, "+" indicates that the diaphragm 5 is convexly deformed in one direction, and "-" indicates that the diaphragm 5 is convexly deformed in another direction. When the diaphragm 5 vibrates in the fourth-order resonance mode, there are four antinode positions A distributed axially symmetrically and two node positions B located between the antinode positions A, as shown in FIG. Figure 23 to Figure 25 As shown; similarly, the effective working space of the pump chamber 8 between the diaphragm 5 and the opposing plate 7 is no longer mainly concentrated in the central area of ​​the diaphragm 5, but is extended to a larger area than the central area, and the vibration energy of the area outside the central large amplitude area of ​​the diaphragm 5 can also be effectively utilized, and the utilization rate of the vibration energy is higher. In the working process, the gap between the diaphragm 5 and the opposing plate 7 can obtain a larger volume change, thereby increasing the output flow rate.

[0146] Since the vibration displacement of the diaphragm 5 is several times or even dozens of times larger than the vibration displacement of the actuator 3, when the diaphragm 5 is used as an excitation source to excite the gas in the pump chamber 8 to produce pressure changes, it is not necessary to set the diaphragm 5 to operate in a first-order resonance mode, a third-order resonance mode or a higher-order centrally symmetrical resonance mode. In a non-centrally symmetrical resonance mode, for example, the above-mentioned second-order resonance mode or fourth-order resonance mode, the large amplitude area of ​​the diaphragm 5 is no longer mainly concentrated in the central area of ​​the diaphragm 5, but extends to a larger area than the central area, thereby achieving a higher utilization rate of the vibration energy.

[0147] The actuator 3 vibrates under external excitation and transmits the vibration energy to the diaphragm 5, thereby causing the diaphragm 5 to vibrate; the resonance mode of the coordinated vibration of the actuator 3 and the diaphragm 5 is related to the structural shape of the substrate 2, the structural shape of the diaphragm 5, and the connection method between the two. The above factors do not constitute a limitation on the scope of protection of the claims of the present invention. The substrate 2 can be annular, which can be but not limited to circular, rectangular, polygonal or elliptical, etc. The shape of the diaphragm 5 can also be but not limited to circular, square, rectangular, polygonal or elliptical, etc. The spacer 4 connected between the substrate 2 and the diaphragm 5 can also be but not limited to circular, square, rectangular, polygonal or elliptical, etc.

[0148] For example, with respect to the diaphragm 5 alone, the diaphragm 5 may be rectangular, and the two sides of the short sides of the diaphragm 54 are fixedly connected to the substrate 21 through the spacers 43, and the two sides of the long sides of the diaphragm 54 are not fixed:

[0149] When the diaphragm 5 vibrates in the second-order resonance mode, there are two antinode positions A distributed along the long side and a node position B located between the antinode positions A; when the diaphragm 5 vibrates in the third-order resonance mode, there are three antinode positions A distributed along the long side and two node positions B located between the antinode positions A, such as Figure 26-27 As shown;

[0150] For another example, still only referring to the diaphragm 5, the diaphragm 5 is rectangular, and both the short side and the long side of the diaphragm 54 are fixedly connected to the substrate 2 through the spacer 4;

[0151] When the diaphragm 5 vibrates in the second-order resonant mode, there are two antinode positions A distributed along the long side and a node position B located between the antinode positions A, such as Fig.28 When the diaphragm 5 vibrates in a higher-order resonance mode, there are also Fig.29 The resonant mode shown has six anti-node positions A and node positions B located between the anti-node positions A.

[0152] The diaphragm 5 can be made of metal film materials, such as copper foil, titanium foil, stainless steel foil, etc. Preferably, the diaphragm 5 is made of polymer materials, such as PET, PI, PPS, PEI, FEP or other polymer film materials, or the diaphragm 5 is made of a composite material composed of a polymer material and a metal material, such as PI copper clad plate / film, PET copper clad plate / film, PET nickel-plated plate / film, carbon fiber metal composite plate / film, etc.; whether it is a polymer material or a composite material composed of a polymer material and a metal material, compared with metal materials, they all show the characteristics of light weight and high elastic strain limit, and the limit amplitude during resonance is usually much higher than that of metal materials, which is particularly suitable for high requirements on flow output, such as heat dissipation of smart 3C terminal products.

[0153] Example 2

[0154] like Fig.30 As shown, the difference between Example 2 and Example 1 is that the spacer 4 has a plurality of spacers 41, and the spacers 41 are all joined to the surface on the side where the second main surface 3-2 of the substrate 2 is located by bonding or integral molding, and the end of the spacer 41 close to the substrate 2 is connected to the substrate 2, and the plurality of spacers 41 are spaced apart and distributed around the annular path to form a groove 4-1 with the actuator 3, and the end of the spacer 41 facing away from the actuator 3 is fully or partially joined to the diaphragm 5 on the annular path around the groove 4-1.

[0155] That is, the substrate 2, the diaphragm 5 and the spacer 4 form an excitation cavity 6, and the spacer 4 forms the inner wall of the excitation cavity 6. The inner wall of the excitation cavity 6 can be closed and has no channel connected to the outside, and the spacer 4 is a ring structure; the inner wall of the excitation cavity 6 can also be open, and the gaps between the multiple spacers 41 arranged at intervals form channels connected to the outside, and the channels connect the excitation cavity 6.

[0156] Example 3

[0157] like Fig.31 As shown, the difference between Example 3 and Example 1 or 2 is that: the piezoelectric sheet 1 is an annular structure with a hole 1-1 running through the center, and the hole 1-1 is arranged opposite to the excitation cavity 6; the effect brought about by this is that the vibration displacement of the area where the actuator 3 is opposite to the hole 1-1 of the piezoelectric sheet 1 is much larger than the displacement at the periphery. At this time, if the effective vibration area of ​​the diaphragm 5 is also arranged to correspond to the hole 1-1 of the piezoelectric sheet 1, the diaphragm 5 can also produce a larger displacement after being excited, thereby, the excitation cavity 6 can obtain a larger volume change, which can further increase the output flow rate to meet application requirements.

[0158] Example 4

[0159] The difference between Example 4 and Example 1, 2 or 3 is that: it also includes a frame plate 10 and an elastic connecting portion 10-1, the frame plate 10 surrounds the actuator 3, one end of the connecting portion 10-1 is connected to the frame plate 10, and the other end is connected to the substrate 2, the substrate 2 is connected to the frame plate 10 by the connecting portion 10-1, and the actuator 3 is elastically supported on the frame plate 10 in a substantially unconstrained manner, the elastic support does not hinder the vibration of the actuator 3, and the outer periphery of the surface of the side opposite to the diaphragm 5 of the opposing plate 7 is fixed to the frame plate 10; the frame plate 10, the connecting portion 10-1 and the substrate 2 can be set separately or integrally formed. The separate setting method is conducive to reducing the processing difficulty of each component, while the integral forming method can improve the integrity of the structure;

[0160] The connecting portion 10-1 may be formed as a continuous annular thin plate, such as Figure 32-33 As shown; the connecting portion 10-1 can also be formed as a plurality of elastic connecting beams arranged discretely, and the plurality of elastic connecting beams are evenly arranged on the outer circumference of the substrate 2, or the plurality of elastic connecting beams are evenly arranged on the outer circumference of the substrate 2 in groups and pairs, and there are gaps between the plurality of elastic connecting beams arranged discretely, so that the frame plate 10 surrounds the actuator 3 in a manner of gaps at the parts other than the connecting portion 10-1, as shown in FIG. Figure 34-35 As shown; the structural types of the connecting portion 10-1 are various and cannot be listed one by one, and are not limited here. As long as the actuator 3 can be elastically supported on the frame plate 10 in a substantially unconstrained manner, it should be regarded as belonging to the protection scope of the present invention. The actuator 3 in this embodiment is elastically supported on the frame plate 10 in a planar supporting manner. Specifically, the base, the connecting portion 10-1 and the frame plate 10 can be integrally formed.

[0161] Example 5

[0162] like Figure 36 to Figure 38 As shown, the difference between Example 5 and Example 1, 2 or 3 is that: the actuator 3 has at least one connecting boss 11 protruding from one side surface facing the opposing plate 7 and located outside the spacer 4, and the connecting boss 11 can be integrally formed with the substrate 2. When there are multiple connecting bosses 11, the multiple connecting bosses 11 are evenly distributed on the outer periphery of the surface of the substrate 2 facing the opposing plate 7, and the opposing plate 7 has a notch 7-2 in the area opposite to the connecting boss 11, and an elastic support portion 7-3 is formed in the notch 7-2, and the connecting boss 11 is fixedly connected to the elastic support portion 7-3 opposite to it; the substrate 2 in this embodiment is elastically supported on the opposing plate 7 in the vertical direction;

[0163] Alternatively, at least one connecting boss 11 located outside the spacer 4 protrudes from one side surface of the actuator 3 facing the opposing plate 7 . The connecting boss 11 is elastic and fixedly connected to one side of the opposing plate 7 close to the substrate 2 .

[0164] Example 6

[0165] like Fig.39 As shown, the difference between the embodiment 6 and the embodiments 1, 2 or 3 is that: it further comprises a frame portion 12 and a support portion 12-1, the frame portion 12 surrounds the actuator 3 and has a height protruding from the actuator 3 along the thickness direction of the substrate 2;

[0166] The support portion 12-1 includes a cantilever portion 12-11 and a holding portion 12-12, wherein the holding portion 12-12 is connected to a node position B of the vibration of the actuator 3, and the holding portion 12-12 is disposed on a side of the actuator 3 away from the opposing plate 7, wherein one end of the cantilever portion 12-11 is connected to a surface of the holding portion 12-12 away from the actuator 3, and the other end is connected to a side of the frame portion 12 away from the opposing plate 7, and the side of the frame portion 12 facing the opposing plate 7 is fixedly connected to the opposing plate 7. The holding portion 12-12 has one or two or more portions disposed at intervals, and the cantilever portion 12-11 has one or two or more portions disposed at intervals, and the holding portion 12-12 may be an independently constructed annular structure when it is one portion.

[0167] The above-mentioned ideal embodiments of the present invention are for inspiration. Through the above-mentioned description, relevant staff can make various changes and modifications without departing from the technical idea of ​​the present invention. The technical scope of the present invention is not limited to the contents of the specification, and its technical scope must be determined according to the scope of the claims.

Claims

1. A piezoelectric fluid pump, characterized in that: It comprises a fluid excitation unit and at least one opposing plate (7); The fluid excitation unit comprises a piezoelectric sheet (1), a substrate (2), a spacer (4) and a diaphragm (5); at least one piezoelectric sheet (1) is bonded to one or both surfaces of the substrate (2) in the thickness direction; the piezoelectric sheet (1) and the substrate (2) are bonded to form an actuator (3); the piezoelectric sheet (1) causes the actuator (3) to vibrate under the stimulation of an electrical signal; the actuator (3) comprises a first main surface (3-1) and a second main surface (3-2) arranged opposite to each other in the thickness direction; the first main surface (3-1) and the second main surface (3-2) are bonded to each other; 1) or / and the second main surface (3-2) are joined with the spacer (4), the spacer (4) is connected to the actuator (3) at one end close to the actuator (3), the spacer (4) and the actuator (3) enclose a groove (4-1) having an opening at one end facing away from the actuator (3); the diaphragm (5) is fixedly connected to the end of the spacer (4) facing away from the actuator (3) and covers the opening of the groove (4-1), so that an excitation cavity (6) is formed between the actuator (3), the groove (4-1) and the diaphragm (5); The opposing plate (7) is arranged at a distance from the actuator (3) on the side of the diaphragm (5), so that a pump cavity (8) is formed between the opposing plate (7) and the diaphragm (5); at least two holes (7-1) communicating with the pump cavity (8) are penetrated in a region of the opposing plate (7) opposite to the diaphragm (5), When the actuator (3) vibrates, the diaphragm (5) is caused to vibrate, and at least one of the holes (7-1) is arranged in an area of ​​the opposing plate (7) that is opposite to the antinode position (A) of the vibration of the diaphragm (5) and an area adjacent to the antinode position (A); The hole portion (7-1) is an inlet or an outlet, wherein at least one hole portion (7-1) is an inlet, and at least one hole portion (7-1) is an outlet, and at least one hole portion (7-1) is provided with a one-way valve (9); At least one hole portion (7-1) provided with a one-way valve (9) is arranged in an area of ​​the opposing plate (7) that is opposite to the antinode position (A) of the vibration of the diaphragm (5) and an area adjacent to the antinode position (A); When the hole portion (7-1) provided with a one-way valve (9) is used as an inlet, the one-way valve (9) at the inlet is used to limit the flow of fluid from the inlet where the one-way valve (9) is located to the pump chamber (8); and when the hole portion (7-1) provided with a one-way valve (9) is used as an outlet, the one-way valve (9) at the outlet is used to limit the flow of fluid from the pump chamber (8) to the outlet where the one-way valve (9) is located, and when the diaphragm (5) vibrates, the area corresponding to each hole portion (7-1) in the pump chamber (8) is excited to produce a greater gas pressure change than the area of ​​the pump chamber (8) corresponding to the peripheral edge of the diaphragm (5), so that the fluid flows into the pump chamber (8) from the inlet and flows out from the pump chamber (8) through the outlet, and the area of ​​the pump chamber (8) corresponding to the peripheral edge of the diaphragm (5) is the edge area (8-1); The spacer (4) is an annular structure, the inner circumferential wall of the spacer (4) and the actuator (3) enclose an annular groove (4-1), and the end of the spacer (4) facing away from the actuator (3) is fully or partially engaged with the diaphragm (5) on an annular path around the groove (4-1); or, the spacer (4) has a plurality of spacers (41), each of which is engaged with the first main surface (3-1) or the second main surface (3-2), and the plurality of spacers (41) are distributed at circumferential intervals around the excitation cavity (6) to enclose the groove (4-1) with the actuator (3), and the end of the spacer (41) facing away from the actuator (3) is fully or partially engaged with the diaphragm (5).

2. The piezoelectric fluid pump according to claim 1, characterized in that: The holes (7-1) are all arranged in an area of ​​the opposing plate (7) that is opposite to the antinode position (A) of the vibration of the diaphragm (5) and an area adjacent to the antinode position (A); Alternatively, the hole portion (7-1) is respectively arranged in an area of ​​the opposing plate (7) that is opposite to the antinode position (A) of the vibration of the diaphragm (5) and an adjacent area of ​​the antinode position (A), and an area of ​​the opposing plate (7) that is opposite to the node position (B) of the vibration of the diaphragm (5) and an adjacent area of ​​the node position (B).

3. The piezoelectric fluid pump according to claim 2, characterized in that: The diaphragm (5) vibrates with only one antinode, at least one hole portion (7-1) provided with the one-way valve (9) serves as a first hole (7-11), and the remaining hole portions (7-1) serve as second holes (7-12), and the second holes (7-12) are not provided with a one-way valve (9); the first hole (7-11) is arranged in an area of ​​the opposing plate (7) that is opposite to an antinode position (A) of the diaphragm (5) vibration and an area adjacent to the antinode position (A); the second hole (7-12) is arranged in an area of ​​the opposing plate (7) that is opposite to a node position (B) of the diaphragm (5) vibration and an area adjacent to the node position (B); One of the first hole (7-11) and the second hole (7-12) is an inlet, and the other is an outlet.

4. The piezoelectric fluid pump according to claim 2, characterized in that: The vibration of the diaphragm (5) has only one antinode, the hole portions (7-1) are all provided with a one-way valve (9), at least one hole portion (7-1) provided with the one-way valve (9) serves as a first hole (7-11), and the remaining hole portions (7-1) serve as second holes (7-12), the one-way valve (9) arranged in the first hole (7-11) and the one-way valve (9) arranged in the second hole (7-12) restrict the flow of fluid in opposite directions, the first hole (7-11) is arranged in an area of ​​the opposing plate (7) that is opposite to an antinode position (A) of the vibration of the diaphragm (5) and an area adjacent to the antinode position (A); the second hole (7-12) is arranged in an area of ​​the opposing plate (7) that is opposite to a node position (B) of the vibration of the diaphragm (5) and an area adjacent to the node position (B); One of the first hole (7-11) and the second hole (7-12) is an inlet, and the other is an outlet.

5. The piezoelectric fluid pump according to claim 2, characterized in that: The diaphragm (5) vibrates with only one antinode, and each of the hole portions (7-1) is provided with a one-way valve (9), wherein at least one hole portion (7-1) provided with the one-way valve (9) serves as a first hole (7-11), and the remaining hole portions (7-1) serve as second holes (7-12), and the one-way valve (9) disposed in the first hole (7-11) and the one-way valve (9) disposed in the second hole (7-12) restrict the flow of fluid in opposite directions, and the first hole (7-11) and the second hole (7-12) are both disposed in an area of ​​the opposing plate (7) that is opposite to an antinode position (A) of the vibration of the diaphragm (5) and an area adjacent to the antinode position (A); One of the first hole (7-11) and the second hole (7-12) is an inlet, and the other is an outlet.

6. The piezoelectric fluid pump according to claim 2, characterized in that: The vibration of the diaphragm (5) has at least two antinodes; At least one hole portion (7-1) provided with the one-way valve (9) is used as a first hole (7-11), and the remaining hole portions (7-1) are used as second holes (7-12); the second hole (7-12) is not provided with a one-way valve (9); the first hole (7-11) is arranged in an area of ​​the opposing plate (7) that is opposite to at least one antinode position (A) of the vibration of the diaphragm (5) and an area adjacent to the antinode position (A); and the second hole (7-12) is arranged in an area of ​​the opposing plate (7) that is opposite to a node position (B) of the vibration of the diaphragm (5) and an area adjacent to the node position (B); One of the first hole (7-11) and the second hole (7-12) is an inlet, and the other is an outlet.

7. The piezoelectric fluid pump according to claim 2, characterized in that: The vibration of the diaphragm (5) has at least two antinodes, the hole portions (7-1) are all provided with a one-way valve (9), at least one hole portion (7-1) provided with the one-way valve (9) serves as a first hole (7-11), and the remaining hole portions (7-1) serve as second holes (7-12), the first hole (7-11) being arranged in an area of ​​the opposing plate (7) that is opposite to at least one antinode position (A) of the vibration of the diaphragm (5) and an area adjacent to the antinode position (A), the second hole (7-12) being arranged in an area of ​​the opposing plate (7) that is opposite to a node position (B) of the vibration of the diaphragm (5) and an area adjacent to the node position (B), and the one-way valve (9) arranged in the first hole (7-11) and the one-way valve (9) arranged in the second hole (7-12) restrict the flow of fluid in opposite directions; One of the first hole (7-11) and the second hole (7-12) is an inlet, and the other is an outlet.

8. The piezoelectric fluid pump according to claim 2, characterized in that: The vibration of the diaphragm (5) has at least two antinodes; At least one hole portion (7-1) provided with the one-way valve (9) serves as a first hole (7-11), and the remaining hole portions (7-1) serve as second holes (7-12), the second hole (7-12) is not provided with a one-way valve (9), and the first hole (7-11) and the second hole are respectively arranged in an area of ​​the opposing plate (7) that is opposite to at least one antinode position (A) of vibration of the diaphragm (5) and an area adjacent to the antinode position (A); One of the first hole (7-11) and the second hole (7-12) is an inlet, and the other is an outlet.

9. The piezoelectric fluid pump according to claim 2, characterized in that: The vibration of the diaphragm (5) has at least two antinodes; The hole portions (7-1) are all provided with a one-way valve (9), at least one hole portion (7-1) provided with the one-way valve (9) serves as a first hole, and the remaining hole portions (7-1) serve as second holes (7-12), the first hole (7-11) and the second hole (7-12) are respectively arranged in an area of ​​the opposing plate (7) that is opposite to at least one antinode position (A) of vibration of the diaphragm (5) and an area adjacent to the antinode position (A); the one-way valve (9) arranged in the first hole (7-11) and the one-way valve (9) arranged in the second hole (7-12) restrict the flow of fluid in opposite directions; One of the first hole (7-11) and the second hole (7-12) is an inlet, and the other is an outlet.

10. The piezoelectric fluid pump according to claim 1, characterized in that: The piezoelectric sheet (1) is in the form of an annular structure with a cavity (1-1) running through the center, and the cavity (1-1) is arranged opposite to the excitation cavity (6).

11. The piezoelectric fluid pump according to claim 1, characterized in that: The diaphragm (5) is made of a polymer material, or a composite material consisting of a polymer material and a metal material.

12. The piezoelectric fluid pump according to any one of claims 1 to 11, characterized in that: It also includes a frame plate (10) and an elastic connecting portion (10-1), wherein the frame plate (10) surrounds the actuator (3), one end of the connecting portion (10-1) is connected to the frame plate (10), and the other end is connected to the actuator (3), and the outer periphery of the surface of the side of the opposing plate (7) opposite to the diaphragm (5) is fixed to the frame plate (10).

13. The piezoelectric fluid pump according to claim 12, characterized in that: The frame plate (10) surrounds the actuator (3) with a gap therebetween except for the connecting portion (10-1).

14. The piezoelectric fluid pump according to any one of claims 1 to 11, characterized in that: At least one connecting boss (11) located outside the spacer (4) protrudes from a surface of one side of the actuator (3) facing the opposing plate (7); a region of the opposing plate (7) opposite to the connecting boss (11) has a notch (7-2); an elastic support portion (7-3) is formed in the notch (7-2); and the connecting boss (11) and the elastic support portion (7-3) opposite to the notch (7-2) are fixedly connected.

15. The piezoelectric fluid pump according to any one of claims 1 to 11, characterized in that: At least one connecting boss (11) located outside the spacer (4) protrudes from a surface of one side of the actuator (3) facing the opposing plate (7); the connecting boss (11) is elastic and fixedly connected to a side of the opposing plate (7) close to the base plate (2).

16. The piezoelectric fluid pump according to any one of claims 1 to 11, characterized in that: It also comprises a frame portion (12) and a support portion (12-1), wherein the frame portion (12) surrounds the actuator (3) and has a height protruding from the actuator (3) along the thickness direction of the substrate (2); The support portion (12-1) comprises a cantilever portion (12-11) and a retaining portion (12-12); the retaining portion (12-12) is joined to a node position (B) of vibration of the actuator (3); the retaining portion (12-12) is arranged on a side of the actuator (3) away from the opposing plate (7); one end of the cantilever portion (12-11) is connected to a surface of the retaining portion (12-12) on a side away from the actuator (3); the other end is connected to a side of the frame portion (12) away from the opposing plate (7); and the frame portion (12) is fixedly connected to the opposing plate (7) on a side facing the opposing plate (7).

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