Piezoelectric micro-flow pump

Abstract

The invention relates to a fluid transfer device, in particular to a piezoelectric micro-flow pump, which comprises a suction cavity, a middle cavity and a discharge cavity, the suction cavity comprises two elastic films, the two elastic films of the suction cavity are respectively connected with a piezoelectric ceramic layer, the piezoelectric ceramic layers of the suction cavity are used for driving the suction cavity to expand or shrink, and the discharge cavity is connected with the middle cavity. The suction cavity is provided with a first fluid inlet channel and a first fluid outlet channel, the discharge cavity comprises two elastic films, the two elastic films of the discharge cavity are respectively connected with a piezoelectric ceramic layer, and the piezoelectric ceramic layers of the discharge cavity are used for driving the discharge cavity to expand or shrink. The discharging cavity is provided with a second fluid inlet channel and a second fluid discharging channel, and the inner cavity of the middle cavity is communicated with the first fluid discharging channel and the second fluid inlet channel. The heat dissipation device is small in size, low in noise, easy to apply to small electronic equipment, more accurate in airflow transmission speed control and suitable for chip heat dissipation.

Description

[0001] This application is a divisional application of the Chinese invention patent application filed by the same applicant with an application date of June 13, 2024, application number 2024107639626, and invention name “Piezoelectric Microfluidic Pump”. Technical Field

[0002] The invention relates to a fluid transfer device, in particular to a piezoelectric microfluidic pump. Background Art

[0003] As the heat flux density of chips increases, electronic products are becoming smaller and smaller, while the requirements for heat dissipation performance are also getting higher and higher. Traditional chip heat dissipation methods have disadvantages such as large size, high noise, and low heat dissipation efficiency. Chip heat dissipation devices such as fans and heat pipes are not suitable for use in small electronic devices due to their large size; liquid cooling is costly and has the risk of leakage. In addition, because the water pump is an indispensable device in the liquid cooling process, the existence of the water pump makes it impossible to reduce the size of the liquid cooling device, and the water pump causes noise pollution due to the high noise when working. Summary of the invention

[0004] The object of the present invention is to provide a piezoelectric microfluidic pump which is small in size, low in noise, easy to be applied to small electronic devices, has more precise air flow transmission speed control, and is suitable for chip heat dissipation.

[0005] To achieve the above-mentioned purpose, the present invention provides a piezoelectric microfluidic pump, comprising a suction chamber, an intermediate chamber, and a discharge chamber, wherein the suction chamber, the intermediate chamber, and the discharge chamber are all closed chambers, the suction chamber comprising two elastic films parallel to each other, the two elastic films of the suction chamber are respectively connected to piezoelectric ceramic layers, the piezoelectric ceramic layers of the suction chamber are used to drive the suction chamber to expand or shrink, a first fluid inlet channel and a first fluid discharge channel are provided on the suction chamber, the discharge chamber comprises two elastic films parallel to each other, the two elastic films of the discharge chamber are respectively connected to piezoelectric ceramic layers, the piezoelectric ceramic layers of the discharge chamber are used to drive the discharge chamber to expand or shrink, a second fluid inlet channel and a second fluid discharge channel are provided on the discharge chamber, the intermediate chamber is connected between the suction chamber and the discharge chamber, and the inner cavity of the intermediate chamber is connected to the first fluid discharge channel and the second fluid inlet channel.

[0006] Further, the piezoelectric microfluidic pump of the present invention includes a first side wall, a second side wall, a first film layer, a second film layer, a third film layer, and a fourth film layer connected to the first side wall and the second side wall and parallel to each other, the first side wall, the second side wall, the first film layer, and the second film layer form the suction chamber, the first side wall, the second side wall, the third film layer, and the fourth film layer form the discharge chamber, the outer walls of the first film layer and the second film layer are respectively connected to the first piezoelectric ceramic layer and the second piezoelectric ceramic layer, the outer walls of the third film layer and the fourth film layer are respectively connected to the third piezoelectric ceramic layer and the fourth piezoelectric ceramic layer, the first piezoelectric ceramic layer and the second piezoelectric ceramic layer are used to drive the suction chamber to expand or shrink, the third piezoelectric ceramic layer and the fourth piezoelectric ceramic layer are used to drive the discharge chamber to expand or shrink, the first fluid inlet channel and the second fluid discharge channel are both arranged on the first side wall, and the first fluid discharge channel and the second fluid inlet channel are both arranged on the second side wall.

[0007] Further, the first fluid inlet channel includes a first air inlet provided on the first side wall and a first air inlet valve provided on the first air inlet, the first fluid outlet channel includes a first exhaust port provided on the second side wall and a first exhaust valve provided on the first exhaust port, the second fluid inlet channel includes a second air inlet provided on the second side wall and a second air inlet valve provided on the second air inlet, and the second fluid outlet channel includes an exhaust port provided on the first side wall and an exhaust valve provided on the exhaust port.

[0008] Furthermore, the first intake valve, the first exhaust valve, the second intake valve, and the second exhaust valve all adopt elastic thin plates, the first intake valve is located on the inner side of the first intake port, the first exhaust valve is located on the outer side of the first exhaust port, the second intake valve is located on the inner side of the second intake port, and the second exhaust valve is located on the outer side of the second exhaust port.

[0009] Furthermore, the first fluid inlet channel and the second fluid outlet channel are respectively a first air inlet and a second air outlet arranged on the first side wall, the first fluid outlet channel and the second fluid inlet channel are respectively a first air outlet and a second air inlet arranged on the second side wall, the first air inlet and the second air inlet are both cones that gradually expand along the fluid inlet direction, and the first exhaust port and the second exhaust port are both cones that gradually expand along the fluid discharge direction.

[0010] The piezoelectric microfluidic pump of the present invention has at least the following beneficial effects:

[0011] The piezoelectric microfluidic pump of the present invention has a suction chamber comprising two elastic films parallel to each other, the two elastic films of the suction chamber are respectively connected with piezoelectric ceramic layers, the piezoelectric ceramic layers of the suction chamber are used to drive the suction chamber to expand or contract, and the discharge chamber comprises two elastic films parallel to each other, the two elastic films of the discharge chamber are respectively connected with piezoelectric ceramic layers, the piezoelectric ceramic layers of the discharge chamber are used to drive the discharge chamber to expand or contract, and the fluid is driven by piezoelectric ceramic driving. The pump has a small size and low noise, is easily applied to small electronic devices, can be packaged together with a chip for chip heat dissipation, and can control the airflow transmission speed by changing the driving frequency and amplitude voltage. The piezoelectric microfluidic pump has high movement accuracy and can control the airflow transmission speed. The system is more precise, and the piezoelectric ceramics can adopt a micron-level thin film structure, or a multi-layer micron-level thin film structure, so as to achieve low-voltage drive. Since the piezoelectric ceramics are capacitive elements, the heat generation is low under the same heat dissipation performance conditions. The piezoelectric microfluidic pump of the present invention is used for chip heat dissipation to further improve the heat dissipation effect of the chip; further, the piezoelectric microfluidic pump of the present invention adopts a jet fluid to dissipate the heat of the chip. The piezoelectric microfluidic pump body is not in direct contact with the chip, and there is no need to press the chip or apply a heat dissipation medium, so the chip will not be damaged. The piezoelectric microfluidic pump of the present invention can also be used for various fluid delivery purposes in other fields such as precise proportioning of reagents and control of reaction rate in chemical reagent preparation, continuous supply of insulin in biomedicine, blood delivery, etc.

[0012] The piezoelectric microfluidic pump of the present invention is described in detail below with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 This is an overall structural diagram of a first embodiment of a piezoelectric microfluidic pump according to the present invention;

[0014] Figure 2 Schematic diagram of the air intake and exhaust process of the first embodiment of the piezoelectric microfluidic pump of the present invention;

[0015] Figure 3 Schematic diagram of the internal gas transfer process of the piezoelectric microfluidic pump embodiment 1 of the present invention;

[0016] Figure 4 This is an overall structural diagram of a second embodiment of a piezoelectric microfluidic pump according to the present invention;

[0017] Figure 5 Schematic diagram of the air intake and exhaust process of the second embodiment of the piezoelectric microfluidic pump of the present invention;

[0018] Figure 6 Schematic diagram of the gas internal transmission process of the second embodiment of the piezoelectric microfluidic pump of the present invention;

[0019] Figure 7 This is an overall structural diagram of the third embodiment of the piezoelectric microfluidic pump of the present invention;

[0020] Figure 8 This is an overall structural diagram of a fourth embodiment of a piezoelectric microfluidic pump according to the present invention;

[0021] Fig. 9 It is a schematic diagram of the structure of the piezoelectric microfluidic pump used for chip heat dissipation of the present invention. DETAILED DESCRIPTION

[0022] like Figure 1 As shown, a piezoelectric microfluidic pump of the present invention comprises a suction chamber 01, an intermediate chamber 02, and a discharge chamber 03. The suction chamber 01, the intermediate chamber 02, and the discharge chamber 03 are all closed chambers. The suction chamber 01 comprises two elastic films parallel to each other, and piezoelectric ceramic layers are respectively connected to the two elastic films of the suction chamber 01. The piezoelectric ceramic layers of the suction chamber 01 are used to drive the suction chamber 01 to expand or shrink. The suction chamber 01 is provided with a first fluid inlet channel and a first fluid discharge channel. The discharge chamber 03 comprises two elastic films parallel to each other, and piezoelectric ceramic layers are respectively connected to the two elastic films of the discharge chamber 03. The piezoelectric ceramic layers of the discharge chamber 03 are used to drive the discharge chamber 03 to expand or shrink. The volume of the intermediate chamber 02 remains unchanged. The piezoelectric ceramic layers of the suction chamber 01 and the discharge chamber 03 are both connected to a power supply. The discharge chamber 03 is provided with a second fluid inlet channel and a second fluid discharge channel. The intermediate chamber 02 is connected between the suction chamber 01 and the discharge chamber 03. The inner cavity of the intermediate chamber 02 is communicated with the first fluid discharge channel and the second fluid inlet channel. The piezoelectric microfluidic pump of the present invention has a suction chamber 01 for sucking fluid, gas or liquid. In the embodiment of the present invention, the suction of gas is taken as an example. The piezoelectric microfluidic pump of the present invention is divided into a suction and exhaust process and an internal fluid circulation process according to the time sequence of the work process, which are as follows:

[0023] During the suction and exhaust process, the piezoelectric ceramic layer of the suction chamber 01 and the piezoelectric ceramic layer of the exhaust chamber 03 are controlled to change in voltage, so that the piezoelectric ceramic layer of the suction chamber 01 and the piezoelectric ceramic layer of the exhaust chamber 03 are bent, the volume of the suction chamber 01 is forced to increase, and the internal air pressure of the suction chamber 01 is reduced. Under the action of the pressure difference, the first fluid inlet channel of the suction chamber 01 is opened and the first fluid outlet channel is closed, so that the suction chamber 01 forms an air suction action, the volume of the exhaust chamber 03 is forced to decrease, the internal air pressure of the exhaust chamber 03 is increased, the second fluid inlet channel of the exhaust chamber 03 is closed, and the second fluid outlet channel is opened, so that the exhaust chamber 03 forms an exhaust action;

[0024] Internal gas circulation process: by controlling the voltage changes of the piezoelectric ceramic layer of the suction chamber 01 and the piezoelectric ceramic layer of the discharge chamber 03, the piezoelectric ceramic layer of the suction chamber 01 and the piezoelectric ceramic layer of the discharge chamber 03 are bent, so that the volume of the suction chamber 01 is forced to decrease, and the internal air pressure of the suction chamber 01 increases. Under the action of the pressure difference, the first fluid discharge channel on the suction chamber 01 is opened, and under the action of the pressure difference, the first fluid inlet channel of the suction chamber 01 is closed, the volume of the discharge chamber 03 is forced to increase, and the internal air pressure of the discharge chamber 03 is reduced, the second fluid inlet channel of the discharge chamber 03 is opened, and the second fluid discharge channel is closed, and the gas in the suction chamber 01 enters the intermediate chamber 02, and enters the discharge chamber 03 through the intermediate chamber 02.

[0025] The piezoelectric microfluidic pump of the present invention forms air flow transmission in one cycle through the process of suction and exhaust and the process of internal gas circulation. The process of air flow transmission can be used to cool the chip, such as Fig. 9 As shown, the piezoelectric microfluidic pump of the present invention is packaged together with the chip for heat dissipation of the chip, and an air inlet 71 and an air outlet 72 are provided on the chip package 07.

[0026] The piezoelectric microfluidic pump of the present invention has a suction chamber 01 including two elastic films parallel to each other, the two elastic films of the suction chamber 01 are respectively connected with piezoelectric ceramic layers, the piezoelectric ceramic layers of the suction chamber 01 are used to drive the suction chamber 01 to expand or contract, and a discharge chamber 03 includes two elastic films parallel to each other, the two elastic films of the discharge chamber 03 are respectively connected with piezoelectric ceramic layers, the piezoelectric ceramic layers of the discharge chamber 03 are used to drive the discharge chamber 03 to expand or contract, and the fluid is driven by piezoelectric ceramic driving. The pump has a small size and low noise, and is easily applied to small electronic devices. The pump can be packaged together with a chip for heat dissipation of the chip, such as Fig. 9 As shown, the air flow transmission speed can be controlled by changing the driving frequency and the amplitude voltage. The piezoelectric microfluidic pump has high motion accuracy and more accurate air flow transmission speed control. In addition, the piezoelectric ceramic can adopt a micron-level thin film structure, or a multi-layer micron-level thin film structure, so as to achieve low-voltage drive. For example, the piezoelectric microfluidic pump of the present invention can be operated when the voltage does not exceed 3.82V. Since the piezoelectric ceramic is a capacitive element, the heat generation is low under the same heat dissipation performance conditions. The piezoelectric microfluidic pump of the present invention is used for chip heat dissipation to further improve the chip heat dissipation effect; further, the piezoelectric microfluidic pump of the present invention adopts a jet fluid to dissipate the chip. The piezoelectric microfluidic pump body is not in direct contact with the chip, and there is no need to press the chip or apply a heat dissipation medium, which will not cause damage to the chip. The piezoelectric microfluidic pump of the present invention can also be used for various fluid delivery purposes in other fields such as precise proportioning of reagents and control of reaction rate in chemical reagent preparation, continuous supply of insulin in biomedicine, and blood delivery.

[0027] like Figure 1The first embodiment of the present invention is a piezoelectric microfluidic pump, comprising a first side wall 41, a second side wall 42, a third side wall 43, and a first film layer 51, a second film layer 52, and a third film layer 53 connected between the first side wall 41 and the second side wall 42 and parallel to each other, wherein the first film layer 51, the second film layer 52, and the third film layer 53 are all made of elastic material, and a suction cavity 01 is formed between the first film layer 51, the second film layer 52, the first side wall 41, and the second side wall 42, and the second film layer 52, the third film layer 53, the first side wall 41, and the second side wall 43 are connected to each other and parallel to each other. 2, an exhaust cavity 03 is formed between the second side wall 42 and the third side wall 43, an intermediate cavity 02 is formed between the second side wall 42 and the third side wall 43, a side of the first film layer 51 away from the second film layer 52, a side of the second film layer 52 away from the first film layer 51, and a side of the third film layer 53 away from the second film layer 52 are respectively connected with the first piezoelectric ceramic layer 61, the second piezoelectric ceramic layer 62, and the third piezoelectric ceramic layer 63, the first fluid inlet channel and the second fluid outlet channel are both arranged on the first side wall 41, and the first fluid outlet channel and the second fluid inlet channel are both arranged on the second side wall 42. Specifically, the first film layer 51, the second film layer 52, and the third film layer 53 can be made of high-strength and high-elastic copper alloy, stainless steel or PPSU (polyphenylene sulfone resin).

[0028] The first fluid inlet channel includes a first air inlet 411 arranged on the first side wall 41 and a first air inlet valve 412 arranged on the first air inlet 411, the first fluid outlet channel includes a first exhaust port 421 arranged on the second side wall 42 and a first exhaust valve 422 arranged on the first exhaust port 421, the second fluid inlet channel includes a second air inlet 423 arranged on the second side wall 42 and a second air inlet valve 424 arranged on the second air inlet 423, and the second fluid outlet channel includes a second exhaust port 413 arranged on the first side wall 41 and a second exhaust valve 414 arranged on the second exhaust port 413. Specifically, the first air intake valve 412, the first exhaust valve 422, the second air intake valve 424, and the second exhaust valve 414 can all be made of elastic thin plates, such as stamped stainless steel thin plates, 304 stainless steel, 316L stainless steel, or thermoplastic formed PPSU plates. The first air intake valve 412 is located on the inside of the first air intake port 411, the first exhaust valve 422 is located on the outside of the first exhaust port 421, the second air intake valve 424 is located on the inside of the second air intake port 423, and the second exhaust valve 414 is located on the outside of the second exhaust port 413.

[0029] like Figure 2As shown, a piezoelectric microfluidic pump of the present invention controls the voltage change of the first piezoelectric ceramic layer 61, the second piezoelectric ceramic layer 62, and the third piezoelectric ceramic layer 63 during the suction and exhaust process, so that the first film layer 51 and the third film layer 53 are bent upward as shown in the figure, and the second film layer 52 is bent downward. At this time, the volume of the suction chamber 01 is forced to increase, and the internal air pressure is reduced. Under the action of the pressure difference on both sides, the first air inlet valve 412 overcomes its own elastic force and changes from a closed state to an open state, forming an air suction action. The first exhaust valve 422 is kept in a closed state due to mechanical limitation, and its seal is tighter under the action of the pressure difference on both sides; at the same time, the volume of the discharge chamber 03 is forced to decrease, and the internal air pressure increases. Under the action of the pressure difference on both sides, the second exhaust valve 414 overcomes its own elastic force and changes from a closed state to an open state, forming an exhaust action. The second air inlet valve 424 is kept in a closed state due to mechanical limitation, and its seal is tighter under the action of the pressure difference on both sides.

[0030] like Figure 3 As shown, during the internal fluid circulation process, the voltage changes of the first piezoelectric ceramic layer 61, the second piezoelectric ceramic layer 62, and the third piezoelectric ceramic layer 63 are controlled to make the first film layer 51 and the third film layer 53 bend downward as shown in the figure, and the second film layer 52 bends upward. At this time, the volume of the suction chamber 01 is forced to decrease, and the internal air pressure increases. Under the action of the pressure difference on both sides, the first exhaust valve 422 overcomes its own elastic force and changes from a closed state to an open state, and presses the gas from the suction chamber 01 into the middle chamber 02. The first intake valve 412 remains in a closed state due to mechanical limitation, and its seal is tighter under the action of the pressure difference on both sides; at the same time, the volume of the discharge chamber 03 is forced to increase, and the internal air pressure decreases. Under the action of the pressure difference on both sides, the second intake valve 424 overcomes its own elastic force and changes from a closed state to an open state, and the gas in the middle chamber 02 is sucked into the discharge chamber 03. The second exhaust valve 414 remains in a closed state due to mechanical limitation, and its seal is tighter under the action of the pressure difference on both sides. The first piezoelectric ceramic layer 61, the second piezoelectric ceramic layer 62, and the third piezoelectric ceramic layer 63 can be piezoelectric ceramics in the shape of a cylinder, a cuboid, or other shapes. Since the first piezoelectric ceramic layer 61, the second piezoelectric ceramic layer 62, and the third piezoelectric ceramic layer 63 are longitudinally distributed, the movement of the piezoelectric microfluidic pump of the present invention is balanced and the vibration is reduced. In addition, since the first piezoelectric ceramic layer 61, the second piezoelectric ceramic layer 62, and the third piezoelectric ceramic layer 63 are arranged in sequence along the deformation direction, fluid transmission is achieved by changing the volumes of the suction chamber and the discharge chamber through coordinated action. The suction chamber and the discharge chamber are arranged longitudinally. Compared with a transverse arrangement, the piezoelectric microfluidic pump of the present invention is smaller in size.

[0031] like Figure 4The second embodiment shown is a piezoelectric microfluidic pump of the present invention, which is different from the above-mentioned embodiment one in that the first fluid inlet channel and the second fluid outlet channel are respectively a first air inlet 415 and a second air outlet 416 arranged on the first side wall 41, and the first fluid outlet channel and the second fluid inlet channel are respectively a first air outlet 425 and a second air inlet 426 arranged on the second side wall 42, and the first air inlet 415 and the second air inlet 426 are both tapered in shape gradually expanding along the fluid inlet direction, and the first exhaust port 425 and the second exhaust port 416 are both tapered in shape gradually expanding along the fluid exhaust direction.

[0032] like Figure 5 As shown, during the air intake and exhaust process, by controlling the voltage changes of the first piezoelectric ceramic layer 61, the second piezoelectric ceramic layer 62, and the third piezoelectric ceramic layer 63, the first film layer 51 and the third film layer 53 are bent upward as shown in the figure, and the second film layer 52 is bent downward. At this time, the volume of the suction chamber 01 is forced to increase, and the internal air pressure decreases. Under the action of the pressure difference on both sides, external air enters the suction chamber 01 through the first air inlet 415, and the air in the middle chamber 02 enters the suction chamber 01 through the first exhaust port 425. Due to the conical structure, the air intake of the first air inlet 415 is greater than the air intake of the first exhaust port 425; at the same time, the volume of the discharge chamber 03 is forced to decrease, and the internal air pressure increases. Under the action of the pressure difference on both sides, the air is discharged from the discharge chamber 03 to the middle chamber 02 through the second air inlet 426, and to the outside of the equipment through the second exhaust port 416. Due to the conical structure, the air outlet discharged to the outside of the equipment through the second exhaust port 416 is greater than the air outlet discharged to the middle chamber 02 through the second air inlet 426, completing the air intake and exhaust process.

[0033] like Figure 6As shown, during the circulation of the internal fluid, the voltage changes of the first piezoelectric ceramic layer 61, the second piezoelectric ceramic layer 62, and the third piezoelectric ceramic layer 63 are controlled so that the first film layer 51 and the third film layer 53 bend downward as shown in the figure, and the second film layer 52 bends upward. At this time, the volume of the suction chamber 01 is forced to decrease and the internal air pressure increases. Under the action of the pressure difference on both sides, the air in the suction chamber 01 is discharged to the outside of the device through the first air inlet 415 and to the middle chamber 02 through the first air outlet 425. Due to the conical structure, the amount of air discharged to the middle chamber 02 through the first air outlet 425 is greater than the amount of air discharged to the outside of the device through the first air inlet 415. At the same time, the volume of the discharge chamber 03 is forced to increase, and the internal air pressure is reduced. Under the action of the pressure difference on both sides, the external air enters the discharge chamber 03 through the second air outlet 416, and the air in the middle chamber 02 enters the discharge chamber 03 through the second air inlet 426. Due to the conical structure, the amount of air entering the discharge chamber 03 through the second air inlet 426 is greater than the amount of air entering the discharge chamber 03 through the second air outlet 416. In one cycle, the amount of air entering the device through the second air outlet 416 is much smaller than the amount of air discharged from the device through the second air inlet 426. The piezoelectric microfluidic pump of the present invention forms airflow transmission through the flow difference.

[0034] like Figure 7 The third embodiment shown in the figure is a piezoelectric microfluidic pump of the present invention, comprising a first side wall 41', a second side wall 42', a third side wall 43', a first film layer 71, a second film layer 72, a third film layer 73, and a fourth film layer 74 connected between the first side wall 41' and the second side wall 42' and parallel to each other, wherein the first side wall 41', the second side wall 42', the first film layer 71, and the second film layer 72 form a suction cavity 01, the first side wall 41', the second side wall 42', the third film layer 73, and the fourth film layer 74 form a discharge cavity 03, an intermediate cavity 02 is formed between the second side wall 42' and the third side wall 43', and the second film layer 72 and the third film layer 73 are connected to each other. A free cavity 04 is formed therebetween, the outer walls of the first film layer 71 and the second film layer 72 are connected to the first piezoelectric ceramic layer 81 and the second piezoelectric ceramic layer 82 respectively, the outer walls of the third film layer 73 and the fourth film layer 74 are connected to the third piezoelectric ceramic layer 83 and the fourth piezoelectric ceramic layer 84 respectively, the first piezoelectric ceramic layer 81 and the second piezoelectric ceramic layer 82 are used to drive the suction cavity 01 to expand or shrink, the third piezoelectric ceramic layer 83 and the fourth piezoelectric ceramic layer 84 are used to drive the discharge cavity 03 to expand or shrink, the first fluid inlet channel and the second fluid discharge channel are both arranged on the first side wall 41', and the first fluid discharge channel and the second fluid inlet channel are both arranged on the second side wall 42'.

[0035] The first fluid inlet channel includes a first air inlet 411' arranged on the first side wall 41' and a first air inlet valve 412' arranged on the first air inlet 411', the first fluid outlet channel includes a first exhaust port 421' arranged on the second side wall 42' and a first exhaust valve 422' arranged on the first exhaust port 421', the second fluid inlet channel includes a second air inlet 423' arranged on the second side wall 42' and a second air inlet valve 424' arranged on the second air inlet 423', and the second fluid outlet channel includes a second exhaust port 413' arranged on the first side wall 41' and a second exhaust valve 414' arranged on the second exhaust port 413'.

[0036] The first air intake valve 412', the first exhaust valve 422', the second air intake valve 424' and the second exhaust valve 414' are all made of elastic thin plates. The first air intake valve 412' is located on the inner side of the first air intake port 411', the first exhaust valve 422' is located on the outer side of the first exhaust port 421', the second air intake valve 424' is located on the inner side of the second air intake port 423', and the second exhaust valve 414' is located on the outer side of the second exhaust port 413'.

[0037] like Figure 8 The fourth embodiment shown is a piezoelectric microfluidic pump of the present invention, which is different from the above-mentioned third embodiment in that the first fluid inlet channel and the second fluid outlet channel are respectively a first air inlet 415' and a second air outlet 416' arranged on the first side wall 41', and the first fluid outlet channel and the second fluid inlet channel are respectively a first air outlet 425' and a second air inlet 426' arranged on the second side wall 42', and the first air inlet 415' and the second air inlet 426' are both tapered in shape gradually expanding along the fluid inlet direction, and the first exhaust port 425' and the second exhaust port 416' are both tapered in shape gradually expanding along the fluid discharge direction.

[0038] Although the disclosure is disclosed as above, the protection scope of the disclosure is not limited thereto. Those skilled in the art may make various changes and modifications without departing from the spirit and scope of the disclosure, and these changes and modifications will fall within the protection scope of the present invention.

Claims

1. A piezoelectric microfluidic pump, characterized in that: The invention comprises an inlet chamber (01), an intermediate chamber (02), and an outlet chamber (03); the inlet chamber (01), the intermediate chamber (02), and the outlet chamber (03) are all closed chambers; the inlet chamber (01) comprises two elastic films parallel to each other; the two elastic films of the inlet chamber (01) are respectively connected to piezoelectric ceramic layers; the piezoelectric ceramic layers of the inlet chamber (01) are used to drive the inlet chamber (01) to expand or contract; the inlet chamber (01) is provided with a first fluid inlet channel and a first fluid outlet channel; the outlet chamber (03) is provided with a first fluid inlet channel and a first fluid outlet channel; the outlet chamber (01 ... The cavity (03) comprises two elastic films parallel to each other, and the two elastic films of the discharge cavity (03) are respectively connected to piezoelectric ceramic layers, and the piezoelectric ceramic layers of the discharge cavity (03) are used to drive the discharge cavity (03) to expand or shrink, and the discharge cavity (03) is provided with a second fluid inlet channel and a second fluid discharge channel, and the intermediate cavity (02) is connected between the suction cavity (01) and the discharge cavity (03), and the inner cavity of the intermediate cavity (02) is connected to the first fluid discharge channel and the second fluid inlet channel.

2. The piezoelectric microfluidic pump according to claim 1, characterized in that: The invention comprises a first side wall (41'), a second side wall (42'), a first film layer (71) parallel to each other and connected between the first side wall (41') and the second side wall (42'), a second film layer (72), a third film layer (73), and a fourth film layer (74), wherein the first side wall (41'), the second side wall (42'), the first film layer (71), and the second film layer (72) form the suction chamber (01), and the first side wall (41'), the second side wall (42'), the third film layer (73), and the fourth film layer (74) form the discharge chamber (02), and the outer side walls of the first film layer (71) and the second film layer (72) are respectively connected to The first piezoelectric ceramic layer (81), the second piezoelectric ceramic layer (82), the third film layer (73), and the fourth film layer (74) are respectively connected to the third piezoelectric ceramic layer (83) and the fourth piezoelectric ceramic layer (84) on their outer walls; the first piezoelectric ceramic layer (81) and the second piezoelectric ceramic layer (82) are used to drive the suction chamber (01) to expand or contract; the third piezoelectric ceramic layer (83) and the fourth piezoelectric ceramic layer (84) are used to drive the discharge chamber (03) to expand or contract; the first fluid inlet channel and the second fluid discharge channel are both arranged on the first side wall (41'); and the first fluid discharge channel and the second fluid inlet channel are both arranged on the second side wall (42').

3. The piezoelectric microfluidic pump according to claim 2, characterized in that: The first fluid inlet channel includes a first air inlet (411') arranged on the first side wall (41') and a first air inlet valve (412') arranged on the first air inlet (411'); the first fluid outlet channel includes a first air outlet (421') arranged on the second side wall (42') and a first air outlet valve (422') arranged on the first air outlet (421'); the second fluid inlet channel includes a second air inlet (423') arranged on the second side wall (42') and a second air inlet valve (424') arranged on the second air inlet (423'); the second fluid outlet channel includes a second air outlet (413') arranged on the first side wall (41') and a second air outlet valve (414') arranged on the second air outlet (413').

4. The piezoelectric microfluidic pump according to claim 3, characterized in that: The first air intake valve (412'), the first exhaust valve (422'), the second air intake valve (424'), and the second exhaust valve (414') are all made of elastic thin plates; the first air intake valve (412') is located on the inner side of the first air intake port (411'), the first exhaust valve (422') is located on the outer side of the first exhaust port (421'), the second air intake valve (424') is located on the inner side of the second air intake port (423'), and the second exhaust valve (414') is located on the outer side of the second exhaust port (413').

5. The piezoelectric microfluidic pump according to claim 4, characterized in that: The first fluid inlet channel and the second fluid outlet channel are respectively a first air inlet (415') and a second air outlet (416') arranged on the first side wall (41'); the first fluid outlet channel and the second fluid inlet channel are respectively a first air outlet (425') and a second air inlet (426') arranged on the second side wall (42'); the first air inlet (415') and the second air inlet (426') are both tapered in shape and gradually expand along the fluid inlet direction; the first air outlet (425') and the second air outlet (416') are both tapered in shape and gradually expand along the fluid outlet direction.

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