Piezoelectric pump with integrated inlet and outlet double passive valves

Abstract

The invention discloses a piezoelectric pump with integrated inlet and outlet double passive valves, which belongs to the technical field of valved piezoelectric pumps and comprises a piezoelectric vibrator, the integrated inlet and outlet passive valves, a pump body, a lower outlet structure and an inlet structure. The piezoelectric vibrator and the pump body are fixedly connected in a sealed mode to form a pump cavity. An inlet structure and a lower outlet structure are arranged on the pump body; the inlet structure comprises a plurality of inlet runner units which are inwards communicated with the interior of the cavity; the integrated inlet and outlet passive valve comprises a double-layer outlet valve plate, a connecting arm and an inlet double-arc straightable valve plate; the double-layer outlet valve plate and the lower outlet structure are arranged in a sliding mode, and when the piezoelectric vibrator vibrates upwards, the piezoelectric vibrator moves upwards to seal a lower outlet. The inlet double-arc-shaped valve plate capable of being straightened comprises an inner arc-shaped valve plate and an outer arc-shaped valve plate which are integrally connected; the outermost side of the outer arc-shaped valve plate is fixedly connected with the outer end of the inlet runner unit; the outer arc-shaped valve plate is completely attached to the arc-surface stop groove of the inlet flow channel unit before being deformed under stress, and the inlet flow channel unit is sealed.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of valve piezoelectric pumps, and particularly relates to a piezoelectric pump with a conjoined inlet and outlet double passive valve. BACKGROUND

[0002] The piezoelectric pump has become a research hotspot in the microfluid field at home and abroad due to its core advantages of small size, fast response, low noise, high precision and low energy consumption, and is widely used in scenes such as aerospace, micro-nano special processing, electronic device heat dissipation and other scenes with strict requirements for equipment miniaturization and control precision.

[0003] The working principle of the piezoelectric pump is based on the inverse piezoelectric effect of piezoelectric materials: by applying an alternating excitation to the piezoelectric wafer, the piezoelectric ceramic is driven to produce micro deformation and convert it into macro vibration, thereby changing the volume of the pump cavity to cause pressure fluctuation in the cavity, and finally realizing the directional transmission of the fluid.

[0004] The traditional valve piezoelectric pump structure sets a one-way valve piece at the outlet and the inlet respectively, and the overall structure has slow response, large power consumption, relatively complex structure, limited flow and pressure regulation range; in addition, most of them are single outlet and inlet, which makes the overall pumping efficiency of the piezoelectric pump low, so it needs to be improved and optimized.

[0005] In summary, there is an urgent need for a piezoelectric pump with a high-efficiency and fast-response inlet and outlet one-way valve structure to solve the problems of low efficiency of fluid unidirectional pumping and insufficient service life of piezoelectric pumps. SUMMARY

[0006] The purpose of the present application is to solve the above problems, and provide a piezoelectric pump with a conjoined inlet and outlet double passive valve.

[0007] The application adopts the following technical scheme:

[0008] A piezoelectric pump with a conjoined inlet and outlet double passive valve comprises: a piezoelectric vibrator 1, an integrated inlet and outlet passive valve 2, a pump body 3, a lower outlet structure 4, and an inlet structure 5.

[0009] The piezoelectric vibrator 1 is sealingly and fixedly connected with the pump body 3 to form a pump cavity 30;

[0010] The pump body 3 is uniformly provided with k groups of inlet structures 5 and n groups of lower outlet structures 4 in the middle, and k > n;

[0011] The inlet structure 5 comprises a pump body inlet 32, an inlet flow channel unit 50 and an intracavity inlet 30a which are sequentially communicated from the outside to the inside of the cavity;

[0012] The inlet flow channel unit 50 comprises an inner flow channel 50a on the inner side and an arc surface stop groove 50b on the outer side upper wall;

[0013] The lower outlet structure 4 includes, from top to bottom, a limiting support column 41, an internal outlet 30b, a transition chamber 42, a conical flow channel 43, and a pump body outlet 33;

[0014] The cavity outlet 30b is located in the middle of the pump cavity 30, and k limiting support columns 41 are evenly distributed around it to form k column sliding grooves 41b.

[0015] The integrated inlet / outlet passive valve 2 includes a double-layer outlet valve plate 20, a connecting arm 21, and an inlet double-arc straightable valve plate 22;

[0016] The double-layer outlet valve plate 20 includes an upper connecting valve plate 20a, a connecting column 20c, and a lower shut-off valve plate 20b, which are fixedly connected from top to bottom.

[0017] k connecting arms 21 are evenly distributed and fixed around the upper connecting valve plate 20a;

[0018] The k connecting arms 21 are sequentially slid up and down in the k column grooves 41b, and pass outward through the k cavity inlets 30a and are located in the inner flow channel 50a.

[0019] The inlet double arc-shaped straightable valve plate 22 includes an inner arc-shaped valve plate 22a and an outer arc-shaped valve plate 22b integrally connected, and its two sides are slidably attached to the side wall of the inlet flow channel unit 50.

[0020] The inner arc-shaped valve plate 22a is fixedly connected to the outer end of the connecting arm 21, and the outermost end of the outer arc-shaped valve plate 22b is fixedly connected to the lower outer wall of the inlet flow channel unit 50.

[0021] Before the double-arc straightable valve plate 22 at the inlet is deformed by force, the outer arc valve plate 22b is completely fitted with the arc-shaped stop groove 50b, and the inner arc valve plate 22a is tangentially fitted with the inner upper wall of the inlet flow channel unit 50.

[0022] The cavity outlet 30b is circular, and the limiting support column 41 is provided with a baffle 41a;

[0023] The upper connecting valve plate 20a is smaller than the cavity outlet 30b, and its upper end is restricted by the baffle plate 41a;

[0024] The diameter of the transition chamber 42 is larger than the diameter of the cavity outlet 30b;

[0025] The lower shut-off valve plate 20b is circular, and its diameter is greater than or equal to the diameter of the cavity outlet 30b, but always smaller than the diameter of the transition chamber 42;

[0026] When the diameter of the lower shut-off valve plate 20b is larger than the diameter of the cavity outlet 30b, it only moves within the transition chamber 42 and seals the cavity outlet 30b when it comes into contact with the upper end face of the transition chamber 42.

[0027] When the diameter of the lower shut-off valve plate 20b is equal to the diameter of the cavity outlet 30b, it moves between the transition chamber 42 and the cavity outlet 30b. When the upper connecting valve plate 20a is in contact with the baffle plate 41a, the lower shut-off valve plate 20b is located inside the cavity outlet 30b.

[0028] Seal the cavity outlet 30b.

[0029] When in use, the piezoelectric vibrator 1 vibrates up and down;

[0030] When the piezoelectric vibrator 1 vibrates upward, it will drive the double-layer outlet valve plate 20 upward, and the lower shut-off valve plate 20b will seal the outlet 30b in the cavity; the inlet double arc straightable valve plate 22 will be straightened through the connecting arm 21, and the fluid will be pumped into the pump cavity 30.

[0031] When the piezoelectric vibrator 1 vibrates downward, it will drive the double-layer outlet valve plate 20 downward, and the inlet double arc straightable valve plate 22 will return to its original shape. The inner arc valve plate 22a is tangentially attached to the inner upper wall of the inlet flow channel unit 50 to form a first-level cutoff, and the outer arc valve plate 22b is completely attached to the arc surface cutoff groove 50b to form a second-level cutoff, sealing the inlet flow channel unit 50. The fluid in the pump chamber 30 bypasses the double-layer outlet valve plate 20 and is pumped out of the pump body 3 through the lower outlet structure 4.

[0032] When the lower end face of the upper connecting valve plate 20a is higher than the lower end face of the connecting arm 21, the size of the upper connecting valve plate 20a relative to the cavity outlet 30b is not limited;

[0033] When the lower shut-off valve plate 20b moves only within the transition chamber 42, the stop plate 41a may not be provided on the limiting support column 41; when it is required that the end face of the lower shut-off valve plate 20b be larger than the cavity outlet 30b, its shape is not restricted.

[0034] The piezoelectric vibrator 1 is composed of a circular piezoelectric ceramic 10 and an elastic substrate 11 bonded together.

[0035] The pump body 3 can be provided with multiple pump chambers 30, and the number of inlet structures 5 corresponding to each pump chamber is more than twice the number of outlet structures 4.

[0036] The pump body inlet 32 ​​and the inner flow channel 50a are arranged in parallel and are both perpendicular to the axis of the pump body outlet 33.

[0037] Another objective of this invention is to provide a method for preparing a piezoelectric pump with integrated inlet and outlet dual passive valves.

[0038] A method for manufacturing a piezoelectric pump with integrated inlet and outlet dual passive valves, comprising the following steps:

[0039] 1) 3D modeling and slicing

[0040] The structure of the pump body (3) and the integrated inlet and outlet passive valve (2) are designed using 3D modeling software. The inlet double arc straightable valve plate (22) should be defined as an independent component during modeling.

[0041] The model is imported into the slicing software for slicing. The pump body (3) is made of rigid photosensitive resin, the inlet double arc straightable valve plate (22) is made of highly elastic flexible photosensitive resin, and the integrated inlet and outlet passive valve 2 is made of rigid photosensitive resin. The print file is generated.

[0042] 2) Printing and production

[0043] First, the selected flexible photosensitive resin is poured into the resin tank. The resin will be stacked layer by layer under the ultraviolet light of the DLP projector. When the inlet double arc straight valve plate (22) is printed, the printer adopts the "lifting and switching" scheme to replace the material with rigid photosensitive resin and continue to print the remaining structure of the integrated inlet and outlet passive valve (2). The printing process of the pump body (3) is the same as that of the integrated inlet and outlet passive valve 2.

[0044] 3) Clean and remove supports

[0045] The printed structure is placed in isopropanol for ultrasonic cleaning and the support is removed. Finally, it is placed in a UV curing chamber for final curing.

[0046] 4) Adhesive assembly

[0047] Utilizing the flexibility of the inlet double arc straightening valve plate (22), it is inserted into the inlet flow channel unit (50) so that the axes of the pump body (3) and the lower shut-off valve plate (20b) of the integrated inlet and outlet passive valve (2) are aligned. Glue is applied to the end of the inlet double arc straightening valve plate (22) for bonding and fixing.

[0048] A stop plate (41a) is glued to each limiting support column (41), and finally the piezoelectric vibrator 1 is glued to the vibrator mounting groove (31);

[0049] The rigid photosensitive resin is an acrylate resin or a polypropylene resin; the flexible photosensitive resin is polydimethylsiloxane (PDMS).

[0050] This invention provides a piezoelectric pump with integrated inlet and outlet dual passive valves, belonging to the technical field of valved piezoelectric pumps. It includes a piezoelectric vibrator, an integrated inlet and outlet passive valve, a pump body, a lower outlet structure, and an inlet structure. The piezoelectric vibrator is sealed and fixedly connected to the pump body to form a pump cavity. The pump body is provided with an inlet structure and a lower outlet structure. The inlet structure includes multiple inlet flow channel units that communicate inward with the cavity. The integrated inlet and outlet passive valve includes a double-layer outlet valve plate, a connecting arm, and an inlet double-arc pullable valve plate. The double-layer outlet valve plate is slidably disposed with the lower outlet structure; when the piezoelectric vibrator vibrates upward, it moves upward to seal the lower outlet. The inlet double-arc pullable valve plate includes an integrally connected inner arc valve plate and an outer arc valve plate. The outermost edge of the outer arc valve plate is fixedly connected to the outer end of the inlet flow channel unit. Before deformation under stress, the outer arc valve plate completely fits the arc-shaped stop groove of the inlet flow channel unit, sealing the inlet flow channel unit.

[0051] In summary, the beneficial effects of the technical solution adopted in this invention compared with the prior art are as follows:

[0052] 1. In this invention, the inner arc-shaped valve plate of the inlet double arc-shaped straightable valve plate of the integrated inlet passive valve can be tangentially fitted to the upper wall of the inlet flow channel unit to achieve primary shut-off (preliminary shut-off) of the inlet when the fluid is pumped out.

[0053] 2. In this invention, the outer arc-shaped valve plate in the integrated inlet and outlet passive valve can be completely fitted with the arc-shaped cut-off groove in the inlet flow channel unit to achieve a two-stage cut-off (almost complete cut-off) at the inlet when the fluid is pumped out; during operation, the up-and-down vibration of the piezoelectric vibrator can drive the integrated inlet and outlet passive valve to move and deform, thereby achieving efficient suction and pumping of fluid;

[0054] 3. In this invention, the inner flow channel of the inlet flow channel unit can be configured as a conical flow channel (with the small opening on the inside), a stepped flow channel, a Tesla flow channel, or other flow channels with reverse cut-off characteristics, thereby improving the cut-off response speed and further enhancing the reverse cut-off effect.

[0055] 4. The device of the present invention can adjust the number of cavities and the number of inlets and outlets corresponding to each cavity according to the usage requirements. It is necessary to control the number of inlets to be more than twice the number of outlets, thereby improving the overall pumping efficiency of the fluid. Attached Figure Description

[0056] Figure 1 Exploded view A of the overall structure of the piezoelectric pump with integrated inlet and outlet dual passive valves of the present invention;

[0057] Figure 2 Exploded view B of the overall structure of the piezoelectric pump with integrated inlet and outlet dual passive valves of the present invention;

[0058] Figure 3 This is a schematic diagram of the internal structure of a piezoelectric pump with integrated inlet and outlet dual passive valves according to the present invention.

[0059] Figure 4 This is a schematic diagram of the deformed state of the inlet double arc-shaped straightable valve plate of the integrated inlet and outlet passive valve in the piezoelectric pump of the present invention.

[0060] Figure 5 This is a schematic diagram of the inlet double arc-shaped straightable valve plate of the integrated inlet and outlet passive valve in the piezoelectric pump of the present invention, when the integrated inlet and outlet passive valve is not deformed.

[0061] Figure 6 This is a schematic diagram showing the position of the integrated inlet and outlet passive valves when the piezoelectric pump of the present invention pumps out fluid.

[0062] Figure 7 This is a schematic diagram illustrating the working principle of a piezoelectric pump with integrated inlet and outlet dual passive valves according to the present invention.

[0063] Figure 8 This is a schematic diagram showing the deformation cycle of the piezoelectric vibrator and the integrated inlet / outlet passive valve during the operation of the piezoelectric pump of the present invention with an integrated inlet / outlet dual passive valve.

[0064] Figure 9 This is a schematic diagram showing the relationship between the number of inlets and outlets of the pump body in Embodiment 3 of the piezoelectric pump with integrated inlet and outlet dual passive valves of the present invention;

[0065] Figure 10 This is a schematic diagram showing the relationship between the number of inlets and outlets in the pump body in Embodiment 4 of the piezoelectric pump with integrated inlet and outlet dual passive valves of the present invention.

[0066] In the attached diagram:

[0067] 1. Piezoelectric vibrator; 10. Piezoelectric ceramic; 11. Elastic substrate;

[0068] 2. Integrated inlet / outlet passive valve; 20. Double-layer outlet valve plate; 20a. Upper connecting valve plate; 20b. Lower shut-off valve plate; 20c. Connecting column; 21. Connecting arm; 21a. Reinforcing strip; 22. Inlet double-arc straightable valve plate; 22a. Inner arc valve plate; 22b. Outer arc valve plate;

[0069] 3. Pump body; 30. Pump chamber; 30a. Chamber inlet; 30b. Chamber outlet; 31. Vibrator mounting slot; 32. Pump body inlet; 33. Pump body outlet;

[0070] 4. Lower outlet structure; 41. Limiting support column; 41a. Baffle plate; 41b. Column groove; 42. Transition chamber; 43. Conical flow channel;

[0071] 5. Inlet structure; 50. Inlet flow channel unit; 50a. Inner flow channel; 50b. Arc-shaped stop groove. Detailed Implementation

[0072] Example 1: A piezoelectric pump with integrated inlet and outlet dual passive valves

[0073] A piezoelectric pump with integrated inlet and outlet dual passive valves includes: a piezoelectric vibrator 1, an integrated inlet and outlet passive valve 2, a pump body 3, a lower outlet structure 4, and an inlet structure 5.

[0074] The piezoelectric vibrator 1 is circular and is sealed and fixed to the pump body 3 through the vibrator mounting groove 31 on the pump body 3 to form the pump cavity 30;

[0075] The pump body 3 has 4 sets of inlet structures 5 evenly distributed around its four sides and 1 set of lower outlet structures 4 in the middle.

[0076] The inlet structure 5 includes a pump body inlet 32, an inlet flow channel unit 50, and an inlet 30a connected sequentially from the outside to the inside of the cavity;

[0077] The inlet flow channel unit 50 includes an inner flow channel 50a on the inner side and an arc-shaped stop groove 50b on the outer upper wall.

[0078] The lower outlet structure 4 includes, from top to bottom, a limiting support column 41, an internal outlet 30b, a transition chamber 42, a conical flow channel 43, and a pump body outlet 33;

[0079] The cavity outlet 30b is circular and is connected outward to the transition chamber 42, the conical flow channel 43, and the pump body outlet 33 in sequence.

[0080] The cavity outlet 30b is located at the center of the pump cavity 30, and four limiting support columns 41 are evenly distributed around it, thereby forming four column sliding grooves 41b.

[0081] Each of the limiting support columns 41 is provided with a baffle 41a;

[0082] The integrated inlet / outlet passive valve 2 includes a double-layer outlet valve plate 20, a connecting arm 21, and an inlet double-arc straightable valve plate 22;

[0083] The double-layer outlet valve plate 20 includes an upper connecting valve plate 20a, a connecting column 20c, and a lower shut-off valve plate 20b, which are fixedly connected from top to bottom.

[0084] The upper connecting valve plate 20a is circular, with four connecting arms 21 evenly distributed and fixed around it. The outer end of the connecting arm 21 is fixed to the inlet double arc straightable valve plate 22.

[0085] Each of the four connecting arms 21 is provided with a reinforcing strip 21a at its upper end;

[0086] The four connecting arms 21 are slidably mounted on the inner sides of the four column grooves 41b, and their outer ends pass through the four cavity inlets 30a and are located in the inner flow channel 50a.

[0087] The diameter of the upper connecting valve plate 20a is smaller than the diameter of the cavity outlet 30b, and its upper end is restricted by the baffle plate 41a;

[0088] The lower shut-off valve plate 20b is circular, and in this embodiment, the diameter of the lower shut-off valve plate 20b is equal to the diameter of the cavity outlet 30b.

[0089] The diameter of the transition chamber 42 is larger than the diameter of the cavity outlet 30b, and the lower shut-off valve plate 20b moves between the transition chamber 42 and the cavity outlet 30b.

[0090] When the upper end face of the upper connecting valve plate 20a is in contact with the lower end face of the baffle plate 41a, the lower shut-off valve plate 20b is located inside the cavity outlet 30b, sealing the cavity outlet 30b.

[0091] The inlet double arc-shaped straightable valve plate 22 includes an inner arc-shaped valve plate 22a and an outer arc-shaped valve plate 22b integrally connected, which are located in the inlet flow channel unit 50, and the two sides of the inlet double arc-shaped straightable valve plate 22 are slidably attached to the side wall of the inlet flow channel unit 50.

[0092] The inner arc-shaped valve plate 22a is fixedly connected to the outer end of the connecting arm 21, and the outermost end of the outer arc-shaped valve plate 22b is fixedly connected to the lower outer wall of the inlet flow channel unit 50.

[0093] Before the double-arc straightable valve plate 22 at the inlet is deformed by force, the outer arc valve plate 22b is completely fitted with the arc-shaped stop groove 50b, and the inner arc valve plate 22a is tangentially fitted with the inner upper wall of the inlet flow channel unit 50. At this time, the inlet flow channel unit 50 can be sealed.

[0094] When in use, the piezoelectric vibrator 1 vibrates up and down;

[0095] When the piezoelectric vibrator 1 vibrates upward, it will drive the double-layer outlet valve plate 20 upward, and the lower shut-off valve plate 20b will seal the outlet 30b in the cavity; then, through the connecting arm 21, the inlet double arc straightable valve plate 22 will be straightened, and the fluid will be pumped into the pump cavity 30.

[0096] When the piezoelectric vibrator 1 vibrates downward, it will drive the double-layer outlet valve plate 20 downward, and the inlet double arc straightable valve plate 22 will return to its original shape. The inner arc valve plate 22a is tangentially attached to the inner upper wall of the inlet flow channel unit 50 to form a first-level cutoff, and the outer arc valve plate 22b is completely attached to the arc surface cutoff groove 50b to form a second-level cutoff, sealing the inlet flow channel unit 50. The fluid in the pump chamber 30 bypasses the double-layer outlet valve plate 20 and is pumped out of the pump body 3 through the lower outlet structure 4.

[0097] The piezoelectric vibrator 1 is made by bonding a circular piezoelectric ceramic 10 and an elastic substrate 11.

[0098] The pump body inlet 32 ​​and the inner flow channel 50a are arranged in parallel and are both perpendicular to the axis of the pump body outlet 33.

[0099] Example 2: A piezoelectric pump with integrated inlet and outlet dual passive valves

[0100] When the lower end face of the upper connecting valve plate 20a is higher than the lower end face of the connecting arm 21, the size of the upper connecting valve plate 20a relative to the cavity outlet 30b is not limited;

[0101] When the diameter of the lower shut-off valve plate 20b is between the diameter of the cavity outlet 30b and the diameter of the transition chamber 42, the lower shut-off valve plate 20b only moves within the transition chamber 42, and its upper end face can be in contact with the upper end face of the transition chamber 42; that is, the distance from the lower end face of the baffle plate 41a to the upper end face of the transition chamber 42 is greater than the distance from the upper end face of the upper connecting valve plate 20a to the upper end face of the lower shut-off valve plate 20b.

[0102] When the above conditions are met, the stop plate 41a may not be provided on the limiting support column 41.

[0103] Example 3: A piezoelectric pump with integrated inlet and outlet dual passive valves

[0104] See appendix Figure 9 In some embodiments, the structure of the pump body 3 is changed, and five sets of inlet structures 5 are evenly distributed around it, and the integrated inlet and outlet passive valve 2 is provided with five connecting arms 21; that is, a single pump chamber 30 with five inlets and one outlet can also achieve the above function.

[0105] Example 4: A piezoelectric pump with integrated inlet and outlet dual passive valves (see attached diagram). Figure 10 In some embodiments, pumping efficiency is improved by setting more inlets and outlets in a single pump chamber or by setting multiple pump chambers; a single pump chamber 30 with 6 inlets and 2 outlets can be used; or two pump chambers 30 with 3 inlets and 1 outlet in each pump chamber can be used; it has been verified that in the device of the present invention, the effect is better when the number of inlets corresponding to a single pump chamber is more than twice the number of outlets.

[0106] Example 5: A piezoelectric pump with integrated inlet and outlet dual passive valves

[0107] In some embodiments, the inner flow channel 50a portion of the inlet flow channel unit 50 can be configured as a conical flow channel (with the small opening on the inside), a semi-conical flow channel, a stepped flow channel, a Tesla flow channel, or other local flow channels with reverse cut-off characteristics, thereby improving the cut-off response speed of the entire inlet flow channel unit 50 and further enhancing the reverse cut-off effect.

[0108] In summary, the piezoelectric pump structure of the present invention, featuring an integrated inlet and outlet dual passive valve, is ingenious. It can use the vibration of a piezoelectric vibrator in the second-order mode to change the pump chamber volume, causing the pump chamber volume to change periodically. It utilizes the pressure difference and the unidirectional flow effect achieved by the integrated inlet and outlet passive valve to realize the continuous pumping of fluid. Furthermore, the number of chambers and the number of inlets and outlets corresponding to each chamber can be changed to improve the fluid pumping efficiency.

[0109] Example 6: A method for manufacturing a piezoelectric pump with integrated inlet and outlet dual passive valves.

[0110] The materials and processes used in the fabrication of the piezoelectric pump with integrated inlet and outlet dual passive valves of this invention are as follows:

[0111] a. Materials used:

[0112] The pump body 3 can be made of rigid photosensitive resin, such as acrylate resin, polypropylene resin, etc.

[0113] In addition to the double-arc straightable valve plate 22 at the inlet, the integrated inlet and outlet passive valve 2 can also be made of rigid photosensitive resin;

[0114] The inlet double-arc straightable valve plate 22 can be made of flexible photosensitive resin, such as polydimethylsiloxane (PDMS).

[0115] b. Manufacturing process:

[0116] The pump body 3 and the integrated inlet / outlet passive valve 2 are printed separately and then glued together using multi-material digital light processing (DLP) technology.

[0117] Step b.1: 3D modeling and slicing

[0118] The structures of the pump body 3 and the integrated inlet and outlet passive valve 2 were designed using 3D modeling software. The double arc-shaped straightable valve plate 22 at the inlet should be defined as an independent component during modeling to facilitate subsequent multi-material fabrication.

[0119] The model is imported into slicing software for slicing, and different materials are assigned to different parts of the model. The pump body is made of rigid photosensitive resin, the inlet double arc straightable valve plate 22 is made of highly elastic flexible photosensitive resin, and the remaining part of the integrated inlet and outlet passive valve 2 is made of rigid photosensitive resin. A print file is then generated.

[0120] Step b.2: Printing and Production

[0121] First, the selected flexible photosensitive resin is poured into the resin tank. The resin will be stacked layer by layer under the ultraviolet light of the DLP projector. When the inlet double arc straightable valve plate 22 is printed, the printer uses the "lifting and switching" scheme to replace the material with rigid photosensitive resin and continue to print the remaining structure of the integrated inlet and outlet passive valve 2. The printing process of the pump body 3 is similar to that of the integrated inlet and outlet passive valve 2, without changing the material in the middle.

[0122] Step b.3: Post-processing (cleaning, support removal)

[0123] The printed structure is placed in isopropyl alcohol (IPA) for ultrasonic cleaning and the support is removed. Finally, it is placed in a UV curing chamber for final curing.

[0124] Step b.4: Adhesive assembly

[0125] The flexible structure of the inlet double arc-shaped straightable valve plate 22 is used to insert it into the inlet flow channel unit 50, so that the axes of the pump body 3 and the lower shut-off valve plate 20b of the integrated inlet and outlet passive valve 2 coincide. Glue is applied to the end of the inlet double arc-shaped straightable valve plate 22 for bonding and fixing.

[0126] Subsequently, a stop plate 41a is glued to each limiting support column 41, and finally the piezoelectric vibrator 1 is glued to the vibrator mounting groove 31.

[0127] The present invention relates to a piezoelectric pump with integrated inlet and outlet dual passive valves, the working principle of which is as follows:

[0128] Referring to the above embodiments, the present invention can be configured with multiple pump chambers and the number of inlets and outlets can be adjusted, but the working principle is the same. Taking the device structure in Embodiment 1 as an example:

[0129] See appendix Figure 6 and attached Figure 7 When in use, an electrical signal is applied to the piezoelectric vibrator 1, and the piezoelectric vibrator 1 is made to periodically vibrate up and down by utilizing the inverse piezoelectric effect;

[0130] The position of maximum deformation of the piezoelectric vibrator 1 is directly opposite the lower outlet structure 4, which improves the response speed of the integrated inlet and outlet passive valve 2 and the pumping efficiency of the fluid.

[0131] When the piezoelectric vibrator 1 vibrates upward, the double-layer outlet valve plate 20 moves upward under the action of pressure difference and force. The upper end of the upper connecting valve plate 20a is connected to the baffle plate 41a, and the lower shut-off valve plate 20b seals the outlet 30b in the cavity. At the same time, the inlet double arc straightable valve plate 22 is straightened through the connecting arm 21, and the fluid is pumped into the pump cavity 30 through the inlet flow channel unit 50.

[0132] When the piezoelectric vibrator 1 vibrates downward, it is subjected to force, and the double-layer outlet valve plate 20 moves downward. The inlet double arc straightable valve plate 22 returns to its original shape. The inner arc valve plate 22a is tangentially attached to the inner upper wall of the inlet flow channel unit 50 to form a first-level cutoff. The outer arc valve plate 22b is completely attached to the arc surface cutoff groove 50b to form a second-level cutoff, completely sealing the inlet flow channel unit 50. At this time, the fluid in the pump chamber 30 bypasses the double-layer outlet valve plate 20 and is pumped out of the pump body 3 through the lower outlet structure 4.

[0133] See appendix Figure 8 During the fluid pumping process, before the inlet double arc straightening valve plate 22 fully returns to its original state (a short response time is required), when the pumping flow rate is large, the inner flow channel 50a can be set as a conical flow channel (small opening on the inside), a semi-conical flow channel, a stepped flow channel, a Tesla flow channel, or other local flow channels with reverse cut-off characteristics, as described in Example 5. The geometric characteristics of the local flow channel itself are used to respond and compensate to prevent fluid backflow, thereby achieving a better cut-off effect.

[0134] In summary, the device of the present invention can realize continuous pumping in and out of fluid, and the integrated inlet and outlet passive valves have a fast response, thereby indirectly improving the liquid pumping efficiency.

Claims

1. A piezoelectric pump with integrated inlet and outlet dual passive valves, comprising: Piezoelectric vibrator (1), integrated inlet and outlet passive valve (2), pump body (3), lower outlet structure (4), inlet structure (5); The piezoelectric vibrator (1) is sealed and fixed to the pump body (3) to form a pump cavity (30). k sets of inlet structures (5) are evenly distributed on the pump body (3), and n sets of lower outlet structures (4) are set in the middle, where k > n; The inlet structure (5) includes a pump body inlet (32), an inlet flow channel unit (50), and an inlet (30a) that are connected sequentially from the outside to the inside of the cavity. The inlet flow channel unit (50) includes an inner flow channel (50a) on the inner side and an arc-shaped stop groove (50b) on the outer upper wall. The lower outlet structure (4) includes a limiting support column (41), an in-cavity outlet (30b), a transition chamber (42), a conical flow channel (43), and a pump body outlet (33) arranged from top to bottom. The outlet (30b) is located in the middle of the pump cavity (30), and k limiting support columns (41) are evenly distributed around it to form k column grooves (41b). The integrated inlet and outlet passive valve (2) includes a double-layer outlet valve plate (20), a connecting arm (21), and an inlet double arc straightening valve plate (22). The double-layer outlet valve plate (20) includes an upper connecting valve plate (20a), a connecting column (20c), and a lower shut-off valve plate (20b) that are fixedly connected from top to bottom. k connecting arms (21) are evenly distributed and fixed around the upper connecting valve plate (20a); k connecting arms (21) are sequentially slid up and down in k column grooves (41b) and pass outward through k cavity inlets (30a) in sequence within the inner flow channel (50a); The inlet double arc straightening valve plate (22) includes an inner arc valve plate (22a) and an outer arc valve plate (22b) that are integrally connected, and their two sides are slidably attached to the side wall of the inlet flow channel unit (50); The inner arc-shaped valve plate (22a) is fixedly connected to the outer end of the connecting arm (21), and the outermost end of the outer arc-shaped valve plate (22b) is fixedly connected to the lower outer wall of the inlet flow channel unit (50); Before the inlet double arc straightening valve plate (22) is deformed by force, the outer arc valve plate (22b) is completely fitted with the arc-shaped stop groove (50b), and the inner arc valve plate (22a) is tangentially fitted with the inner upper wall of the inlet flow channel unit (50).

2. The piezoelectric pump with integrated inlet and outlet dual passive valves according to claim 1, characterized in that: The cavity outlet (30b) is circular, and the limiting support column (41) is provided with a baffle (41a). The upper connecting valve plate (20a) is smaller than the cavity outlet (30b), and its upper end is restricted by the baffle plate (41a). The diameter of the transition chamber (42) is larger than the diameter of the cavity outlet (30b); The lower shut-off valve plate (20b) is circular, and its diameter is greater than or equal to the diameter of the cavity outlet (30b), but always smaller than the diameter of the transition chamber (42); When the diameter of the lower shut-off valve plate (20b) is larger than the diameter of the cavity outlet (30b), it only moves within the transition chamber (42) and seals the cavity outlet (30b) when it comes into contact with the upper end face of the transition chamber (42). When the diameter of the lower shut-off valve plate (20b) is equal to the diameter of the cavity outlet (30b), it moves between the transition chamber (42) and the cavity outlet (30b). When the upper connecting valve plate (20a) is in contact with the baffle plate (41a), the lower shut-off valve plate (20b) is located inside the cavity outlet (30b). Seal the cavity outlet (30b).

3. The piezoelectric pump with integrated inlet and outlet dual passive valves according to claim 2, characterized in that: When in use, the piezoelectric vibrator (1) vibrates up and down; When the piezoelectric vibrator (1) vibrates upward, it will drive the double-layer outlet valve plate (20) upward, and the lower shut-off valve plate (20b) will seal the outlet (30b) inside the cavity; the inlet double arc straightening valve plate (22) will be straightened through the connecting arm (21), and the fluid will be pumped into the pump cavity (30). When the piezoelectric vibrator (1) vibrates downward, it will drive the double-layer outlet valve plate (20) downward, and the inlet double arc straightening valve plate (22) will return to its original state. The inner arc valve plate (22a) will be tangentially attached to the inner upper wall of the inlet flow channel unit (50) to form a first-level cutoff. The outer arc valve plate (22b) will be completely attached to the arc surface cutoff groove (50b) to form a second-level cutoff, sealing the inlet flow channel unit (50). The fluid in the pump chamber (30) will bypass the double-layer outlet valve plate (20) and be pumped out of the pump body (3) through the lower outlet structure (4).

4. A piezoelectric pump with integrated inlet and outlet dual passive valves according to claim 2 or 3, characterized in that: When the lower end face of the upper connecting valve plate (20a) is higher than the lower end face of the connecting arm (21), the size of the upper connecting valve plate (20a) relative to the cavity outlet (30b) is not limited; When the lower shut-off valve plate (20b) moves only within the transition chamber (42), no baffle plate (41a) is provided on the limiting support column (41); when it is required that the end face of the lower shut-off valve plate (20b) is larger than the cavity outlet (30b), its shape is not restricted.

5. The piezoelectric pump with integrated inlet and outlet dual passive valves according to claim 4, characterized in that: The piezoelectric vibrator (1) is composed of a circular piezoelectric ceramic 10 and an elastic substrate (11) bonded together.

6. The piezoelectric pump with integrated inlet and outlet dual passive valves according to claim 5, characterized in that: The pump body (3) is provided with multiple pump chambers (30), and the number of inlet structures (5) corresponding to each pump chamber is more than twice the number of outlet structures (4).

7. A piezoelectric pump with integrated inlet and outlet dual passive valves according to claim 6, characterized in that: The pump body inlet (32) and the inner flow channel (50a) are arranged in parallel and are both perpendicular to the axis of the pump body outlet (33).

8. The method for preparing a piezoelectric pump with integrated inlet and outlet dual passive valves as described in claim 1, comprising the following steps: 1) 3D modeling and slicing The structure of the pump body (3) and the integrated inlet and outlet passive valve (2) are designed using 3D modeling software. The inlet double arc straightening valve plate (22) should be defined as an independent component during modeling. The model was imported into the slicing software for slicing. The pump body (3) was made of rigid photosensitive resin, the inlet double arc straightening valve plate (22) was made of highly elastic flexible photosensitive resin, and the integrated inlet and outlet passive valve 2 was made of rigid photosensitive resin. The print file was generated. 2) Printing and production First, the selected flexible photosensitive resin is poured into the resin tank. The resin will be stacked layer by layer under the ultraviolet light of the DLP projector. When the inlet double arc straightening valve plate (22) is printed, the printer adopts the "lifting and lowering switching" scheme to replace the material with rigid photosensitive resin and continue to print the remaining structure of the integrated inlet and outlet passive valve (2). The printing process of the pump body (3) is the same as that of the integrated inlet and outlet passive valve 2. 3) Clean and remove supports The printed structure is placed in isopropanol for ultrasonic cleaning and the support is removed. Finally, it is placed in a UV curing chamber for final curing. 4) Adhesive assembly Utilizing the flexibility of the inlet double arc straightening valve plate (22), it is inserted into the inlet flow channel unit (50) so that the axes of the pump body (3) and the lower shut-off valve plate (20b) of the integrated inlet and outlet passive valve (2) are aligned. Glue is applied to the end of the inlet double arc straightening valve plate (22) for bonding and fixing. A stop plate (41a) is glued to each limiting support column (41), and finally the piezoelectric vibrator 1 is glued to the vibrator mounting groove (31).

9. The method for manufacturing a piezoelectric pump with integrated inlet and outlet dual passive valves according to claim 8, characterized in that: The rigid photosensitive resin is an acrylate resin or a polypropylene resin; the flexible photosensitive resin is polydimethylsiloxane (PDMS).

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