A valve plate structure, valve assembly and piezoelectric pump

Abstract

The present invention relates to the technical field of piezoelectric pumps, and in particular to a valve plate structure, a valve assembly and a piezoelectric pump, wherein the valve plate structure comprises: a valve plate body, the valve plate body is made of metal, the valve plate body has at least two windows, a valve extending from the valve plate body is provided in the window, and the valve comprises a connecting arm connected to the valve plate body and a valve flap connected to the connecting arm; wherein the valve flap can swing away from or close to the window along the thickness direction of the valve plate body under the action of an external force, and the thickness of the connecting arm is less than the thickness of the valve flap. The present invention fundamentally solves the service life problem of the valve plate by setting the valve plate body to be made of metal material, because the toughness and rigidity of the metal material are higher than those of the existing polymer materials, and by reducing the thickness of the connecting arm on the valve, the valve is easier to open. Compared with the prior art, the service life of the valve plate is improved, and the switching performance of the valve plate is guaranteed.

Description

Technical Field

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

[0002] The basic working principle of ceramic piezoelectric pumps is based on the deformation characteristics of piezoelectric materials. When voltage is applied, the piezoelectric ceramic element will deform, usually bending or stretching. By periodically applying voltage, the piezoelectric ceramic element will vibrate, thereby promoting the flow of liquid or gas. Due to its unique working mechanism and broad application prospects, it has become an important direction for the research and development of micro pump technology.

[0003] In the prior art, a Chinese invention patent application with publication number CN114992098A disclosed on September 2, 2022 a resonantly excited piezoelectric pump, which mainly includes an integrated valve plate arranged on a pump body, a pump chamber connected to the pump body, a substrate arranged in the pump chamber, and a piezoelectric ceramic that drives the substrate to vibrate; during specific operation, the vibration of the piezoelectric ceramic drives the substrate to move up and down in the pump chamber, thereby realizing that the fluid enters from the first valve plate of the pump body valve plate, enters the pump chamber and flows out from the second valve plate, thereby realizing continuous output.

[0004] However, the valve plate of the above-mentioned piezoelectric pump is made of a polymer flexible film material, which greatly reduces the performance and life of the piezoelectric pump. Summary of the invention

[0005] In view of at least one of the above technical problems, the present invention provides a valve plate structure, a valve assembly and a piezoelectric pump, which improve the material and structure to improve the life and performance of the piezoelectric pump.

[0006] According to a first aspect of the present invention, there is provided a valve plate structure, comprising:

[0007] A valve body, wherein the valve body is made of metal and has at least two windows. A valve extending from the valve body is provided in each window. The valve includes a connecting arm connected to the valve body and a valve flap connected to the connecting arm.

[0008] Wherein, the valve flap can swing away from or approach the window along the thickness direction of the valve plate body under the action of external force, and the thickness of the connecting arm is smaller than the thickness of the valve flap.

[0009] In some embodiments of the present invention, the thickness of the valve flap is the same as the thickness of the valve plate body, and the thickness of the connecting arm is 10% to 90% of the thickness of the valve flap.

[0010] In some embodiments of the present invention, the connecting arm and the valve disc are integrally formed, and the connecting arm is processed by a semi-etching process to form a corrosion plane lower than the sealing surface of the valve disc.

[0011] In some embodiments of the present invention, the valve is arranged coplanarly with the valve plate body in an initial state, and the corrosion plane is arranged parallel to the plane where the valve plate body is located in the initial state.

[0012] In some embodiments of the present invention, the connecting arm further has an opening, and the opening penetrates along the thickness direction of the connecting arm.

[0013] In some embodiments of the present invention, the opening is provided in the middle of the connecting arm and extends from the root of the connecting arm to the side wall of the valve flap.

[0014] According to a second aspect of the present invention, there is further provided a valve assembly, comprising a first support plate, a second support plate and a valve sheet structure as described in any one of the first aspects and sandwiched therebetween, wherein:

[0015] The first support plate and the second support plate are both made of metal;

[0016] The first support plate and the second support plate both have a fluid inlet and a fluid outlet, and the fluid inlet and the fluid outlet are respectively arranged on both sides of the window in the thickness direction, and the fluid inlet corresponds to the sealing surface of the valve flap in the valve sheet structure. When the sealing surface of the valve flap is away from the fluid inlet, the fluid inlet and the fluid outlet where the valve flap is located are opened, and when the sealing surface of the valve flap is attached to the fluid inlet, the fluid inlet and the fluid outlet where the valve flap is located are closed.

[0017] In some embodiments of the present invention, the fluid outlet also has a half-etched groove adapted to the window, the half-etched groove is located on a side close to the valve plate structure and extends in a direction away from the valve plate structure, the half-etched groove is used to provide an opening and closing space for the valve, and the half-etched groove is connected to the opening on the valve plate structure so that when the valve is opened, the fluid medium passes through the opening and the valve disc gap at the same time.

[0018] In some embodiments of the present invention, the size of the fluid inlet is adapted to the valve disc, and an annular step coplanar with the valve disc body is etched at the fluid inlet.

[0019] According to a third aspect of the present invention, a piezoelectric pump is also provided, comprising a pump chamber, a substrate connected to the pump chamber, a piezoelectric ceramic fixed on the substrate, a valve assembly as described in any one of the second aspects and connected to the pump chamber, and a base plate connected to the valve assembly.

[0020] The beneficial effects of the present invention are as follows: the present invention fundamentally solves the service life problem of the valve plate by setting the valve plate body to be made of metal material, because the toughness and rigidity of the metal material are higher than those of the existing polymer materials, and the valve is easier to open by thinning the thickness of the connecting arm on the valve. Compared with the prior art, the service life of the valve plate is improved and the switching performance of the valve plate is guaranteed. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0022] Figure 1 It is a structural schematic diagram of the valve plate structure in an embodiment of the present invention;

[0023] Figure 2 In the embodiment of the present invention Figure 1 The AA section view and the structural schematic diagram when all valves are open;

[0024] Figure 3 In the embodiment of the present invention Figure 1 The BB section view and the structural diagram when all valves are open;

[0025] Figure 4 A schematic diagram of the structure of a valve assembly in an embodiment of the present invention;

[0026] Figure 5 It is a schematic diagram of the explosion decomposition structure of the valve assembly in an embodiment of the present invention;

[0027] Figure 6 In the embodiment of the present invention Figure 5 A local enlarged view of point C in FIG.

[0028] Figure 7 In the embodiment of the present invention Figure 5 A local enlarged view of point D in FIG.

[0029] Figure 8 In the embodiment of the present invention Figure 4 EE section view in the figure;

[0030] Fig. 9 4 is a cross-sectional view of a piezoelectric pump in an embodiment of the present invention. DETAILED DESCRIPTION

[0031] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments.

[0032] It should be noted that when an element is referred to as being "fixed to" another element, it may be directly on the other element or there may be a central element. When an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be a central element at the same time. The terms "vertical", "horizontal", "left", "right" and similar expressions used herein are for illustrative purposes only and do not represent the only implementation method.

[0033] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art of the present invention. The terms used in the specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The term "and / or" used herein includes any and all combinations of one or more related listed items.

[0034] In the embodiment of the present invention, the service life is improved by setting the valve plate structure in the form of a metal part, but the rigidity of the metal part is very strong, so the valve made of a conventional metal cantilever valve is usually not easy to open. The metal valve plate of the piezoelectric pump of the present invention adopts a semi-etched and opened hole solution to reduce the rigidity of the metal valve plate. The thickness of the valve root position of the semi-etched metal valve plate is thinned, and an opening is set at the valve root position of the semi-etched metal valve plate, so that the stress at the root position of the cantilever valve is reduced by at least 50%, so that the metal valve plate is easier to open. The structure of the embodiment of the present invention is described in detail below.

[0035] like Figures 1 to 3 The valve plate structure shown in the figure comprises a valve plate body 1, and the valve plate body 1 is made of metal. Figure 1 As shown in the figure, the valve body 1 has at least two windows 11, and the window 11 has a valve 12 extending from the valve body 1. The valve 12 includes a connecting arm 12a connected to the valve body 1 and a valve flap 12b connected to the connecting arm 12a. In some embodiments of the present invention, the metal material is a material with durability, fatigue resistance and corrosion resistance, for example, it can be stainless steel, titanium alloy, copper alloy and the like.

[0036] like Figure 2As shown in, in the embodiment of the present invention, the valve flap 12b can swing away from or close to the window 11 along the thickness direction of the valve plate body 1 under the action of external force, where the external force refers to the suction or pressure on the valve 12 caused by the pressure change of the pump chamber 4 in the piezoelectric pump, and the thickness of the connecting arm 12a is less than the thickness of the valve flap 12b. In the embodiment of the present invention, the thickness of the valve plate body 1 is about 0.05mm-0.2mm. By setting the thickness of the connecting arm 12a to be lower than the thickness of the valve flap 12b, the valve 12 can be opened easily, avoiding the problem of difficulty in opening due to the excessive rigidity of the valve 12.

[0037] In the above embodiment, by setting the valve plate body 1 to be a metal material, since the toughness and rigidity of the metal material are higher than those of the existing polymer materials, the problem of the service life of the valve plate is fundamentally solved, and by reducing the thickness of the connecting arm 12a on the valve 12, the valve 12 is easier to open. Compared with the prior art, the service life of the valve plate is improved and the switching performance of the valve plate is guaranteed.

[0038] Based on the above examples, please continue to refer to Figure 2 In order to facilitate the opening and closing of the valve 12, the thickness of the valve flap 12b is the same as the thickness of the valve body 1. At the same time, in order to make the connecting arm 12a easy to open, the thickness of the connecting arm 12a is 10% to 90% of the thickness of the valve flap 12b. For example, this thickness can be 40%, 50%, 60%, etc., and those skilled in the art can choose according to actual needs. Figure 2 As shown in , when the valve 12 is horizontal, the valve flap 12b contacts the valve port to achieve closure, and when the valve flap 12b is pressed by the fluid, the connecting arm 12a bends, thereby achieving the opening of the valve 12.

[0039] In the embodiment of the present invention, the connecting arm 12a and the valve flap 12b are integrally formed, and the connecting arm 12a is processed by a semi-etching process to form an erosion plane 12c lower than the sealing surface of the valve flap 12b. Figure 1 As shown in the figure, the shape of the window 11 is cut out on the valve body 1 by etching or laser cutting, so that the cantilever valve 12 is formed, and the valve 12 is semi-etched by semi-etching process, so that the thickness of the root of the valve 12 is corroded to form a corrosion plane 12c. The semi-etching process makes the valve 12 respond faster, the starting pressure is lower, the fatigue response is reduced, and the fluid dynamics performance is optimized.

[0040] Please continue to refer to Figure 2The valve 12 is arranged coplanar with the valve body 1 in the initial state, and the corrosion plane 12c is arranged parallel to the surface of the valve body 1 in the initial state. This arrangement further improves the reliability and stability of the valve 12 when it is closed. Since the upper surface of the valve flap 12b is coplanar with the upper surface of the valve body 1 in the initial state, the valve port only needs to fit the valve body 1 to achieve contact with the valve flap 12b, thereby cooperating with the rigidity of the metal valve 12 itself to improve its sealing performance when it is closed.

[0041] In the embodiment of the present invention, in order to further improve the response speed of the valve 12 and reduce the starting pressure of the valve 12, the connecting arm 12a is further provided with an opening 12d, which runs through the thickness direction of the connecting arm 12a. The width of the opening 12d can be 10% to 90% of the width of the connecting arm 12a. For example, the width of the opening 12d can be 40%, 50%, 60%, etc. By setting the opening 12d, the area of ​​the connecting arm 12a is further reduced, so that the valve 12 is easier to open. The specific position of the opening 12d is as follows. Figure 1 As shown in the figure, the opening 12d is arranged in the middle of the connecting arm 12a and extends from the root of the connecting arm 12a to the side wall of the valve flap 12b. By arranging it in the middle and making the area of ​​the opening 12d as large as possible, the connecting arm 12a is symmetrical on both sides and as long as possible, thereby further reducing the pressure of the valve 12 to start.

[0042] While transforming the metal valve disc, we also redesigned the metal upper and lower supports, taking into account the sealing performance of the metal valve disc and the metal upper and lower supports, as well as the slight deformation of the metal valve disc and the metal upper and lower supports caused by the materials and process. The larger the contact area between the metal valve disc and the metal upper and lower supports, the worse the sealing effect will be. Therefore, we retained the sealing step on the metal upper and lower supports while adding a semi-etched step, so that the contact surface between the metal valve and the metal support is small enough, thereby making it easier to achieve a sealing effect; at the same time, the semi-etched step also reserves sufficient vibration space for the metal valve disc; the specific structural form of the valve assembly in the embodiment of the present invention is introduced in detail below.

[0043] like Figures 4 to 8 As shown in the figure, a valve assembly is also provided in an embodiment of the present invention, comprising a first support plate 2, a second support plate 3 and the above-mentioned valve plate structure sandwiched therebetween, wherein: the first support plate 2 and the second support plate 3 are both made of metal; it should be pointed out here that the metal material can adopt the same structural form as the above-mentioned valve plate body 1, and in terms of thickness, it will be greater than the thickness of the valve plate body 1 in order to provide sufficient support.

[0044] Please continue to refer to Figure 4 and Figure 5In the embodiment of the present invention, the first support plate 2 and the second support plate 3 are both provided with a fluid inlet 31 and a fluid outlet 21, which are respectively arranged on both sides of the window 11 in the thickness direction, and the fluid inlet 31 corresponds to the sealing surface of the valve flap 12b in the valve sheet structure. When the sealing surface of the valve flap 12b is away from the fluid inlet 31, the fluid inlet 31 and the fluid outlet 21 where the valve flap 12b is located are opened, and when the sealing surface of the valve flap 12b is attached to the fluid inlet 31, the fluid inlet 31 and the fluid outlet 21 where the valve flap 12b is located are closed. Figure 8 As shown in the figure, when the valve flap 12b is in contact with the fluid inlet 31, the inlet and outlet where the valve flap 12b is located are closed; while on the right side, when the valve flap 12b is open, the fluid can flow from the inlet to the outlet.

[0045] Please refer to Figure 6 The fluid outlet 21 also has a half-etched groove 22 adapted to the window 11. The half-etched groove 22 is located on the side close to the valve plate structure and extends in the direction away from the valve plate structure. The half-etched groove 22 is used to provide an opening and closing space for the valve 12. The half-etched groove 22 is connected to the opening 12d on the valve plate structure, so that when the valve 12 is opened, the fluid medium passes through the opening 12d and the gap between the valve flap 12b at the same time. In this way, by setting the opening 12d on the valve 12 and cooperating with the half-etched groove 22 at the fluid outlet 21, when the valve flap 12b is opened, Figure 8 As shown in , part of the fluid flows out from the opening 12d, and part flows out from the other side of the valve flap 12b, thereby reducing the flow resistance and making it easier for the fluid to pass through the inlet and outlet. Figure 8 It can be seen that Figure 8 The E in the figure is the opening area of ​​a conventional valve, while the F is the excess valve opening area of ​​the present application compared with the prior art; that is, through the above arrangement, the cross-sectional area through which the liquid passes is increased, thereby reducing the flow resistance and allowing the liquid to pass through the valve hole more easily.

[0046] In the embodiment of the present invention, in order to further improve the sealing performance, Figure 7 As shown in the figure, the size of the fluid inlet 31 is matched with the valve flap 12b, and an annular step 32 coplanar with the valve body 1 is etched at the fluid inlet 31. It should be pointed out here that matching means that the fluid inlet 31 can be blocked when the valve flap 12b is closed, and the annular step 32 is provided to make the contact area between the metal valve 12 and the fluid inlet 31 small enough, so that the pressure will be greater, further improving the sealing effect.

[0047] In an embodiment of the present invention, a piezoelectric pump is also provided. Fig. 9As shown in , it includes a pump chamber 4, a substrate 5 connected to the pump chamber 4, a piezoelectric ceramic 6 fixed on the substrate 5, the valve assembly connected to the pump chamber 4, and a bottom plate 7 connected to the valve assembly. Specifically, during operation, the volume of the pump chamber 4 changes through the vibration of the piezoelectric ceramic 6, that is, when the piezoelectric ceramic 6 drives the substrate 5 to move upward, the pump chamber 4 is under negative pressure, at which time the valve flap 12b on the left is opened and the valve flap 12b on the right is closed, so that the fluid enters the pump chamber 4; on the contrary, when the piezoelectric ceramic 6 drives the substrate 5 to move downward, the pump chamber 4 is under positive pressure, at which time the valve flap 12b on the right is opened and the valve flap 12b on the left is closed, so that the fluid is discharged. The reciprocating vibration of the piezoelectric ceramic 6 realizes the continuous output of the fluid.

[0048] Those skilled in the art should understand that the present invention is not limited to the above embodiments, and the above embodiments and descriptions are only for explaining the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention may have various changes and improvements, and these changes and improvements fall within the scope of the present invention to be protected. The scope of protection of the present invention is defined by the attached claims and their equivalents.

Claims

1. A valve assembly, characterized in that: It includes a first support plate, a second support plate and a valve plate structure sandwiched between the first support plate and the second support plate, wherein: The valve plate structure comprises a valve plate body, the valve plate body is made of metal, the valve plate body has at least two windows, the windows have valves extending from the valve plate body, and the valve comprises a connecting arm connected to the valve plate body and a valve flap connected to the connecting arm; The first support plate and the second support plate are both made of metal; The first support plate and the second support plate are both provided with a fluid inlet and a fluid outlet, the fluid inlet and the fluid outlet are respectively arranged on both sides of the window in the thickness direction, the fluid inlet corresponds to the sealing surface of the valve disc in the valve plate structure, when the sealing surface of the valve disc is away from the fluid inlet, the fluid inlet and the fluid outlet where the valve disc is located are opened, and when the sealing surface of the valve disc is attached to the fluid inlet, the fluid inlet and the fluid outlet where the valve disc is located are closed; The fluid outlet further has a half-etched groove adapted to the window, the half-etched groove is located on a side close to the valve plate structure and extends in a direction away from the valve plate structure, the half-etched groove is used to provide an opening and closing space for the valve, and the half-etched groove is communicated with an opening on the valve plate structure, so that when the valve is opened, the fluid medium passes through the opening and the valve disc gap at the same time; Wherein, the valve flap can swing away from or approach the window along the thickness direction of the valve plate body under the action of external force, and the thickness of the connecting arm is smaller than the thickness of the valve flap.

2. The valve assembly according to claim 1, characterized in that The thickness of the valve flap is the same as the thickness of the valve plate body, and the thickness of the connecting arm is 10% to 90% of the thickness of the valve flap.

3. The valve assembly according to claim 2, characterized in that The connecting arm is integrally formed with the valve disc, and the connecting arm is processed by a semi-etching process to form a corrosion plane lower than the sealing surface of the valve disc.

4. The valve assembly according to claim 3, characterized in that The valve is arranged coplanarly with the valve plate body in an initial state, and the corrosion plane is arranged parallel to the plane where the valve plate body is located in the initial state.

5. The valve assembly according to claim 1, characterized in that The connecting arm also has an opening, and the opening penetrates along the thickness direction of the connecting arm.

6. The valve assembly according to claim 5, characterized in that The opening is arranged in the middle of the connecting arm and extends from the root of the connecting arm to the side wall of the valve flap.

7. The valve assembly according to claim 1, characterized in that The size of the fluid inlet is matched with the valve disc, and an annular step coplanar with the valve disc body is formed by etching at the fluid inlet.

8. A piezoelectric pump, characterized in that: The invention comprises a pump chamber, a substrate connected to the pump chamber, a piezoelectric ceramic fixed on the substrate, a valve assembly as claimed in any one of claims 1 to 7 connected to the pump chamber, and a bottom plate connected to the valve assembly.

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