Pressure detection system and microflow pump

Abstract

The invention relates to a pressure detection system and a micro-flow pump in the technical field of fluid pumps, and the pressure detection system comprises a shell, a pressure sensor, a pressure sensor and a controller, the elastic film is mounted in the cavity and divides the cavity into a first chamber and a second chamber which are not communicated with each other; the liquid inlet is formed in the shell and is communicated with the first cavity and the exterior of the shell; the first electrode plate is mounted on one side, facing the second cavity, of the elastic film; the second electrode plate is mounted in the second cavity, and the second electrode plate and the first electrode plate are oppositely arranged; and the first flexible hinge is formed on the elastic film, is in an annular shape and is arranged around the first electrode slice. The pressure detection system has good pressure detection sensitivity, alarm information can be timely and accurately transmitted out when the hydraulic pressure of the micro-flow pump exceeds a threshold value, and therefore the risk is reduced.

Description

Technical Field

[0001] The present application relates to the technical field of fluid pumps, and in particular to a pressure detection system and a microfluidic pump. Background Art

[0002] At present, most electronic syringe pumps on the market use a mechanical structure and use piston propulsion to deliver liquids. The different working states of the electronic syringe pump can be judged by detecting the resistance of the push rod. However, due to the existence of piston resistance, this method is not very sensitive and will impose a large cumulative pressure on the liquid path. At the moment of blockage removal, a large dose of liquid may be infused in a short time, which poses certain safety risks.

[0003] As an important part of microfluidic technology, MEMS microfluidic pumps have broad prospects in medical applications, biology, chemistry, agriculture, beauty, bathroom, etc. with their simple structure, light volume, low frequency operation, low power consumption and other advantages. In actual work, the matching abnormal detection and control system is a very important part of the whole system. Especially in applications with high requirements for safety and stability, all states of the equipment must be monitored during operation to prevent potential risks caused by abnormal states such as pipeline blockage, empty reservoir, pump chip failure, bubble retention, liquid leakage, etc. However, the current microfluidic pump has a low pressure detection sensitivity, and it is difficult to transmit alarm information in a timely and accurate manner, which is prone to danger. Summary of the invention

[0004] In view of the problems existing in the background technology, the present application provides a pressure detection system and a microfluidic pump. The pressure detection system has good pressure detection sensitivity, which is conducive to timely and accurate transmission of alarm information when the hydraulic pressure of the microfluidic pump exceeds the threshold, thereby reducing risks.

[0005] According to one aspect of the present invention, there is provided a pressure detection system, comprising: a shell, a cavity being formed in the shell; an elastic membrane, the elastic membrane being installed in the cavity to separate the cavity into a first chamber and a second chamber that are not connected to each other; a liquid inlet, the liquid inlet being opened on the shell to connect the first chamber with the outside of the shell; a first electrode sheet, the first electrode sheet being installed on a side of the elastic membrane facing the second chamber; a second electrode sheet, the second electrode sheet being installed in the second chamber, the second electrode sheet being arranged opposite to the first electrode sheet; and a first flexible hinge, the first flexible hinge being formed on the elastic membrane, in a ring shape, and arranged around the first electrode sheet.

[0006] By using the pressure detection system in the technical solution, the liquid inlet of the shell is connected to the microfluidic pump, and the liquid pumped by the microfluidic pump is connected to the first chamber. When the pressure of the microfluidic pump rises, the hydraulic pressure will overcome the elasticity of the first flexible hinge and the elastic membrane to push the elastic membrane to move in the direction of the second electrode sheet, until the pressure of the microfluidic pump rises to be able to push the elastic membrane and the first electrode sheet thereon to move until the first electrode sheet contacts the second electrode sheet, indicating that the pressure of the microfluidic pump is too high at this time, the first electrode sheet is connected to the second electrode sheet, and an electrical signal is output, which can issue a blockage alarm. The first flexible hinge can improve the accuracy of the elastic membrane moving to the contact between the first electrode sheet and the second electrode sheet under the action of a predetermined hydraulic pressure, so that the pressure detection sensitivity is higher, ensuring that the alarm information is transmitted in a timely and accurate manner when the hydraulic pressure of the microfluidic pump exceeds the threshold, thereby reducing the risk.

[0007] In some embodiments of the present invention, the elastic film is made of polydimethylsiloxane.

[0008] In some embodiments of the present invention, the elastic membrane has a first surface and a second surface facing each other, and the elastic membrane forms a depression on the first surface and / or a depression on the second surface in a certain annular area to form the first flexible hinge.

[0009] In some embodiments of the present invention, the recess is formed on the elastic film by etching.

[0010] In some embodiments of the present invention, the pressure detection system further comprises: an exhaust hole, wherein the exhaust hole is provided on the shell and connects the second chamber with the outside of the shell.

[0011] According to another aspect of the present invention, there is provided a microfluidic pump, comprising: the above-mentioned pressure detection system; a substrate, a flow channel is formed on the substrate, and a liquid inlet and a liquid outlet are formed at both ends of the flow channel respectively; the pressure detection system is installed on the substrate; a pressure detection channel, the pressure detection channel is formed on the substrate, one end of the pressure detection channel is connected to a side of the flow channel close to the liquid outlet, and the other end is connected to the liquid inlet.

[0012] In some embodiments of the present invention, more than two pressure detection systems are installed on the substrate, the liquid inlet of each pressure detection system is connected to the pressure detection channel, and the liquid pressure when the first electrode sheet and the second electrode sheet of each pressure detection system are in contact are arranged in sequence from small to large.

[0013] In some embodiments of the present invention, the flow channel includes a first flow channel and a second flow channel; the microfluidic pump also includes: a film, the film is connected between the first flow channel and the second flow channel, a liquid storage cavity connected to the first flow channel and the second flow channel is formed in the film, the end of the first flow channel away from the liquid storage cavity forms the liquid inlet, and the end of the second flow channel away from the liquid storage cavity forms the liquid outlet; a first one-way valve, the first one-way valve is installed on the first flow channel, the direction is from the liquid inlet to the liquid storage cavity; a second one-way valve, the second one-way valve is installed on the second flow channel, the direction is from the liquid storage cavity to the liquid outlet, and is located between the pressure detection channel and the liquid storage cavity; a driving mechanism, the driving mechanism is installed on the substrate, and is used to squeeze the film to pump out the liquid stored in the liquid storage cavity through the second flow channel, the second one-way valve, and the liquid outlet; or, release the squeezing of the film, the film recovers, the liquid storage cavity expands, and the external liquid is pumped in through the liquid inlet, the second flow channel, and the second one-way valve.

[0014] In some embodiments of the present invention, a mounting groove is provided on the base, and the mounting groove is connected to the position of the film; the driving mechanism includes: a motion actuator installed in the mounting groove; a second flexible hinge connecting the motion actuator and the mounting groove; a piezoelectric ceramic installed in the mounting groove and located on the side of the motion actuator away from the film; the piezoelectric ceramic is deformed when energized, driving the motion actuator to move toward the film, thereby squeezing the film; or, the piezoelectric ceramic is de-energized and restored to its original state, and the second flexible hinge is deformed again to drive the motion actuator to move in a direction away from the film, thereby releasing the squeezing of the film.

[0015] In some embodiments of the present invention, two mounting grooves are provided on the base, and the two mounting grooves are located on opposite sides of the film; and the driving mechanism is installed in both mounting grooves. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Various other advantages and benefits will become apparent to those of ordinary skill in the art by reading the detailed description of the preferred embodiments below. The accompanying drawings are only for the purpose of illustrating the preferred embodiments and are not to be considered as limiting the present application. Also, the same reference symbols are used throughout the accompanying drawings to represent the same components. In the accompanying drawings:

[0017] Figure 1 It is a schematic diagram of the overall structure of the pressure detection system of the present invention;

[0018] Figure 2 yes Figure 1 A partial enlarged view of part A;

[0019] Figure 3 It is a schematic diagram of the overall structure of the microfluidic pump of the present invention;

[0020] Figure 4 is a cross-sectional view of the microfluidic pump of the present invention;

[0021] Figure 5 It is a cross-sectional view showing the assembly of the pressure detection system and the microfluidic pump;

[0022] Figure 6 It is a schematic diagram showing the assembly of more than two pressure detection systems and a microfluidic pump;

[0023] Figure 7 It is a cross-sectional view showing the assembly of two or more pressure detection systems and a microfluidic pump;

[0024] Figure 8 It is a cross-sectional view showing the driving mechanism;

[0025] Fig. 9 It is a schematic diagram showing the symmetrical cooperation between the driving mechanism and the film;

[0026] Fig.10 yes Fig. 9 A partial enlarged view of part B.

[0027] The reference numerals in the accompanying drawings represent the following:

[0028] 100, pressure detection system; 101, housing; 102, elastic membrane; 103, liquid inlet; 104, first electrode sheet; 105, second electrode sheet; 106, first flexible hinge; 107, first chamber; 108, second chamber; 109, exhaust hole; 110, signal line;

[0029] 200, microfluidic pump; 201, substrate; 202, pressure detection channel; 203, liquid inlet; 204, liquid outlet; 205, accommodating chamber; 206, first flow channel; 207, second flow channel; 208, film; 209, first one-way valve; 210, second one-way valve; 211, liquid storage chamber; 212, mounting groove; 213, motion actuator; 214, second flexible hinge; 215, piezoelectric ceramic; 216, channel. DETAILED DESCRIPTION

[0030] It should be clear that the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in the field without creative work are within the scope of protection of the present application.

[0031] When the following description refers to the drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the present application. Instead, they are only examples of devices and methods consistent with some aspects of the present application as detailed in the attached claims.

[0032] In the description of the present application, it should be understood that the terms "first", "second", etc. are used for descriptive purposes only and should not be understood as indicating or implying relative importance. For those of ordinary skill in the art, the specific meanings of the above terms in the present application can be understood according to the specific circumstances. In addition, in the description of the present application, unless otherwise specified, "multiple" refers to two or more. "And / or" describes the association relationship of associated objects, indicating that three relationships may exist. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. The character " / " generally indicates that the objects associated before and after are in an "or" relationship.

[0033] The present application embodiment discloses a pressure detection system. Figure 1 and Figure 2 As shown, the pressure detection system 100 includes a shell 101, an elastic membrane 102, a liquid inlet 103, a first electrode sheet 104, a second electrode sheet 105 and a first flexible hinge 106; wherein a cavity is formed in the shell 101; the elastic membrane 102 is installed in the cavity, and the elastic membrane 102 divides the cavity into a first chamber 107 and a second chamber 108 that are not connected to each other; the liquid inlet 103 is opened on the shell 101, and the liquid inlet 103 connects the first chamber 107 and the outside of the shell 101; the first electrode sheet 104 is installed on the side of the elastic membrane 102 facing the second chamber 108; the second electrode sheet 105 is installed in the second chamber 108, and the second electrode sheet 105 is arranged opposite to the first electrode sheet 104; the first flexible hinge 106 is formed on the elastic membrane 102, the first flexible hinge 106 is annular, and the first flexible hinge 106 is arranged around the first electrode sheet 104.

[0034] By using the pressure detection system 100 in the present technical solution, the liquid inlet 103 of the housing 101 is connected to the microfluidic pump 200, and the liquid pumped by the microfluidic pump 200 is connected to the first chamber 107. When the pressure of the microfluidic pump 200 rises, the hydraulic pressure will overcome the elasticity of the first flexible hinge 106 and the elastic membrane 102 to push the elastic membrane 102 to move in the direction of the second electrode sheet 105, until the pressure of the microfluidic pump 200 rises to be able to push the elastic membrane 102 and the first electrode sheet 104 thereon to move until the first electrode sheet 104 contacts the second electrode sheet 105, indicating that the pressure of the microfluidic pump 200 is too large at this time, the first electrode sheet 104 and the second electrode sheet 105 are connected, and an electrical signal is output, and a blockage alarm can be issued. The first flexible hinge 106 can improve the accuracy of the elastic membrane 102 moving to the contact between the first electrode sheet 104 and the second electrode sheet 105 under the action of a predetermined hydraulic pressure, so that the pressure detection sensitivity is higher, and it is ensured that the alarm information is transmitted in a timely and accurate manner when the hydraulic pressure of the microfluidic pump 200 exceeds the threshold, thereby reducing the risk.

[0035] Furthermore, the first electrode sheet 104 and the second electrode sheet 105 can be connected to an audible and visual alarm through a signal line 110, and the audible and visual alarm can issue a relatively obvious blocking alarm.

[0036] In some embodiments of the present invention, the material of the elastic film 102 is polydimethylsiloxane. Polydimethylsiloxane (PDMS) has the advantages of transparency, excellent elasticity and good biocompatibility.

[0037] Furthermore, the housing 101 may also be made of a transparent material to visualize the status of the pressure detection system 100 .

[0038] Specifically, in this embodiment, the shell 101 is made of PDMS material, the wall thickness of the shell 101 is relatively large, and the shell 101 and the elastic membrane 102 are integrated.

[0039] For PDMS materials, before PDMS is completely polymerized, two layers of PDMS are aligned and stacked together, and there are still active molecules that can be cross-linked at the interface of the two layers. Therefore, heating the two layers of PDMS can further solidify them, making the two layers of PDMS irreversibly bonded together, and finally obtaining a PDMS silicon-based pressure detection system 100 with a three-dimensional structure.

[0040] In some embodiments of the present invention, Figure 1 and Figure 2 As shown, the elastic membrane 102 has a first surface and a second surface facing each other. The elastic membrane 102 forms a depression on the first surface and / or a depression on the second surface in a certain annular area to form a first flexible hinge 106 .

[0041] It should be noted that the elastic membrane 102 can form a depression on the first surface to form the first flexible hinge 106 at a certain ring width, or can form a depression on the second surface to form the first flexible hinge 106, or can form depressions on the first surface and the second surface to form the first flexible hinge 106 together.

[0042] Specifically, in this embodiment, the elastic membrane 102 forms depressions on the first surface and the second surface respectively, which together constitute the first flexible hinge 106; the two depressions are both arc-shaped grooves and are arranged opposite to each other.

[0043] Furthermore, the recess is formed on the elastic film 102 by etching.

[0044] Specifically, in this embodiment, the first flexible hinge 106 is formed by using photolithography technology.

[0045] In this embodiment, the first flexible mechanism can be simplified as a slender straight rod, which is supported at only one end and freely suspended at the other end. In this case, the relationship between the deflection and pressure of the first flexible hinge 106 mechanism can be described by the bending equation of the cantilever beam. The calculation formula for the deformation deflection of the first flexible hinge 106 mechanism is as follows:

[0046] δ = K(P * L^3) / (3 * E * I) (1)

[0047] Among them, δ is the deflection of the first flexible hinge 106 mechanism of the suspension pressure detection system 100, K is the stiffness coefficient of the first flexible hinge 106 mechanism, P is the pressure of the liquid flowing through the microfluidic pump 200, L is the radius value of the first flexible hinge 106 mechanism, E is the Young's modulus of the material of the first flexible hinge 106 mechanism, and I is the cross-sectional moment of inertia of the first flexible hinge 106 mechanism.

[0048] The moment of inertia of the cross section I depends on the geometry of the cross section. For a rectangular cross section, the moment of inertia can be expressed as:

[0049] I = (b * h^3) / 12 (2)

[0050] Where b is the arc length of the cross section and h is the thickness of the cross section.

[0051] Through finite element simulation analysis and calculation, the K value can be obtained, thereby obtaining the displacement required when the two electrode sheets on the pressure detection system 100 are in contact, which corresponds to the pressure value of the liquid.

[0052] In some embodiments of the present invention, Figure 1 As shown, the pressure detection system 100 further includes an exhaust hole 109 , which is opened on the shell 101 and connects the second chamber 108 and the outside of the shell 101 .

[0053] When the hydraulic pressure overcomes the elasticity of the first flexible hinge 106 and the elastic membrane 102 and pushes the elastic membrane 102 to move in the direction of the second electrode sheet 105, the volume of the second chamber 108 will be compressed. The setting of the exhaust hole 109 helps to avoid the gas in the second chamber 108 being compressed and causing the movement of the elastic membrane 102 to be obstructed, so that when the hydraulic pressure of the microfluidic pump 200 exceeds the threshold, the first electrode sheet 104 and the second electrode sheet 105 still cannot contact each other, thereby affecting the accuracy of the hydraulic pressure detection.

[0054] Furthermore, more than two exhaust holes 109 are evenly provided on the shell 101 to improve the exhaust and pressure relief efficiency of the second chamber 108 .

[0055] The present application also discloses a microfluidic pump. Figure 3 and Figure 4 As shown, the microfluidic pump 200 includes the above-mentioned pressure detection system 100, and also includes a substrate 201 and a pressure detection channel 202; wherein, a flow channel is formed on the substrate 201, and a liquid inlet 203 and a liquid outlet 204 are formed at both ends of the flow channel respectively; the pressure detection system 100 is installed on the substrate 201; the pressure detection channel 202 is formed on the substrate 201, one end of the pressure detection channel 202 is connected to a side of the flow channel close to the liquid outlet 204, and the other end is connected to the liquid inlet 103.

[0056] When the microfluidic pump 200 is running, under the pumping pressure, the liquid enters the flow channel through the liquid inlet 203 of the base 201, and is then pumped to the target position through the liquid outlet 204, connecting the liquid inlet 103 of the shell 101 with the side of the flow channel close to the liquid outlet 204 through the pressure detection channel 202. When the flow channel is blocked or the like, the liquid pressure rises, and the liquid will press the elastic membrane 102 in the direction of the second chamber 108 from the first chamber 107 of the shell 101, thereby overcoming the elastic effect of the first flexible hinge 106 to connect the first electrode sheet 104 with the second electrode sheet 105, completing the pressure detection and the alarm when the hydraulic pressure of the microfluidic pump 200 exceeds the threshold.

[0057] In this embodiment, if Figure 3 and Figure 5 As shown, a accommodating cavity 205 adapted to the shell 101 is opened on the base 201, and the accommodating cavity 205 is close to the flow channel and arranged at a distance from the flow channel, so that the distance between the side of the accommodating cavity 205 close to the flow channel and the flow channel is as close as possible, the first chamber 107 and the liquid inlet 103 of the shell 101 are arranged close to the flow channel in the accommodating cavity 205, so that the distance between the liquid inlet 103 and the flow channel is as close as possible, and the pressure detection channel 202 is connected to the liquid inlet 103 and the flow channel in a straight line arrangement on the base 201, so that the pressure detection channel 202 can connect the liquid inlet 103 and the flow channel in a point-to-line connection manner.

[0058] In some embodiments of the present invention, Figure 6 and Figure 7 As shown, more than two pressure detection systems 100 are installed on the substrate 201, and the liquid inlet 103 of each pressure detection system 100 is connected to the pressure detection channel 202. The liquid pressure when the first electrode sheet 104 and the second electrode sheet 105 of each pressure detection system 100 are in contact is arranged in sequence from small to large.

[0059] Specifically, in this embodiment, three accommodating cavities 205 of the same specifications are arranged side by side on the base 201 in a direction perpendicular to the flow channel, and a pressure detection system 100 is installed in each accommodating cavity 205 in the same manner. The liquid inlet 103 of each pressure detection system 100 can be independently connected to the flow channel through its own pressure detection channel 202, or can be connected to a pressure detection channel 202 by opening a channel 216 in parallel on the base 201.

[0060] The liquid pressures of the first electrode sheet 104 and the second electrode sheet 105 of each pressure detection system 100 when in contact are arranged in sequence from small to large, mainly by changing the thickness and radius size of the first flexible hinge 106. When the liquid pressure is gradually increased and the electrode sheets are turned on, liquid contact pressures corresponding to different interface thickness sizes are obtained.

[0061] As shown in the following table, according to the alarm pressure required by the product micro flow pump 200, it can be designed as a low pressure alarm of 60KPa, a medium pressure alarm pressure value of 80KPa and a high pressure alarm pressure value of 100KPa.

[0062] Table 1: Contact pressure corresponding to different interface thicknesses

[0063] Radius size 800μm 800μm 800μm Thickness of the section 10μm 11μm 11.8μm Contact pressure 60KPa 80KPa 100KPa

[0064] For the blockage alarm of the microfluidic pump 200, the alarm is divided into different high, medium and low pressure levels according to the severity of the blockage. Such graded alarm helps the user to quickly and effectively judge the blockage situation and take corresponding measures.

[0065] It should be noted that the specific high, medium and low pressure alarm thresholds depend on the design and application requirements of the microfluidic pump 200, and can be based on the following factors:

[0066] Equipment characteristics: Microfluidic pumps 200 of different models and specifications have different working characteristics, such as maximum working pressure, flow rate, etc., and the corresponding alarm thresholds can be determined based on these characteristics.

[0067] Fluid properties: The microfluidic pumps 200 in different application fields may carry fluids with different properties, such as viscosity, particle content, etc. These fluid properties will affect the severity of the blockage, so the corresponding alarm threshold can be set according to the fluid properties.

[0068] Application requirements: According to different application scenarios and the required flow, pressure and other requirements, the corresponding alarm pressure level can be set. For example, for some applications with high flow requirements, a lower pressure threshold may be defined as a high pressure alarm.

[0069] The pressure detection system 100 with the first flexible hinge 106 of different cross-sectional thicknesses is packaged and installed in the base 201 of the microfluidic pump 200. The flow channels are respectively connected with the first chambers 107 of the low-pressure pressure detection system 100, the medium-pressure pressure detection system 100 and the high-pressure pressure detection system 100. When the pressure in the pipeline reaches the low pressure (60KPa), the electrode sheet of the low-pressure pressure detection system 100 is turned on and sends a signal; when the pipeline pressure rises to the medium pressure (80KPa), the electrode sheet of the medium-pressure pressure detection system 100 is turned on and sends a signal; when the pipeline pressure rises to the high pressure (100KPa), the electrode sheet of the high-pressure pressure detection system 100 is turned on and sends a signal.

[0070] Through the above-mentioned modular pressure detection system 100 with various pressure alarms, pressure alarm thresholds at different stages can be set; it can meet the application scenarios and usage requirements of the microfluidic pump 200, and the modularization of the pressure detection system 100 on the substrate 201 is also convenient for maintenance and replacement.

[0071] Pressure detection system 100 points High, medium and low level pressure detection plays an important role in the normal operation and safety of the micro flow pump 200, and has the following significance:

[0072] Operation monitoring: By detecting the pressure of the microfluidic pump 200, its working status can be monitored in real time. The normal low pressure threshold can be used to confirm whether the microfluidic pump 200 is operating normally, so as to promptly detect possible faults or abnormal conditions. If the pressure value is abnormal, it may mean that there is a blockage, leakage, overload or other problems. Timely pressure detection can help users avoid further damage and accidents.

[0073] Safety protection: The pressure detection of the microfluidic pump 200 is also one of the important measures to ensure the safety of users and equipment. When the pressure exceeds the high pressure threshold setting range, the alarm and safety shutdown device can be triggered to prevent the equipment from overloading, being damaged or endangering the safety of the operator. Through timely alarm and emergency shutdown, liquid leakage, explosion or other dangerous situations caused by excessive pressure can be prevented.

[0074] Quality control: Pressure detection can also help monitor and control the quality and stability of fluid delivery. Different application scenarios have specific requirements for flow and pressure. By real-time detection of the pressure of the microfluidic pump 200, feedback control or alarm can be performed on the flow to ensure the stability and consistency of fluid delivery.

[0075] Fault diagnosis: Regularly testing and recording the pressure of the microfluidic pump 200 can help users perform fault diagnosis and maintenance. By analyzing historical data and pressure trends, potential faults can be predicted and prevented, and repair or replacement measures can be taken in time to ensure the reliability and continuous operation of the microfluidic pump 200.

[0076] In some embodiments of the present invention, the substrate 201 is made of an elastic material, and further, it can be made of an elastic and transparent material to visualize the running state of the flow channel.

[0077] In this embodiment, the substrate 201 is made of PDMS material, which has the advantages of transparency and good biocompatibility.

[0078] Furthermore, the housing 101 and the substrate 201 can be integrated to obtain a PDMS silicon-based microfluidic pump 200 with a pressure detection system 100, which can precisely control the MEMS microfluidic pump 200, accurately detect whether the pressure exceeds a threshold, and promptly alarm.

[0079] In some embodiments of the present invention, Figure 4 and Figure 8 As shown, the flow channel includes a first flow channel 206 and a second flow channel 207; the microfluidic pump 200 also includes a film 208, a first one-way valve 209, a second one-way valve 210 and a driving mechanism.

[0080] Among them, the film 208 is connected between the first flow channel 206 and the second flow channel 207, and a liquid storage cavity 211 connected to the first flow channel 206 and the second flow channel 207 is formed in the film 208. The end of the first flow channel 206 away from the liquid storage cavity 211 forms a liquid inlet 203, and the end of the second flow channel 207 away from the liquid storage cavity 211 forms a liquid outlet 204.

[0081] The first one-way valve 209 is installed in the first flow channel 206, and the direction of the first one-way valve 209 is from the liquid inlet 203 to the liquid storage chamber 211; the second one-way valve 210 is installed in the second flow channel 207, and the direction of the second one-way valve 210 is from the liquid storage chamber 211 to the liquid outlet 204, and the second one-way valve 210 is located between the pressure detection channel 202 and the liquid storage chamber 211.

[0082] The driving mechanism is installed on the base 201, and is used to squeeze the film 208 to pump out the liquid stored in the liquid storage chamber 211 through the second flow channel 207, the second one-way valve 210, and the liquid outlet 204; or, the driving mechanism releases the squeezing of the film 208, the film 208 recovers, and the liquid storage chamber 211 expands, and the external liquid is pumped into the liquid storage chamber 211 through the liquid inlet 203, the second flow channel 207, and the second one-way valve 210.

[0083] In some embodiments of the present invention, Figure 8 As shown, a mounting groove 212 is provided on the base 201 , and the mounting groove 212 is connected to the position of the film 208 , that is, the mounting groove 212 is connected to the space where the film 208 is located.

[0084] The driving mechanism includes a motion actuator 213, a second flexible hinge 214 and a piezoelectric ceramic 215, wherein the motion actuator 213 is installed in the mounting groove 212; the second flexible hinge 214 connects the motion actuator 213 and the mounting groove 212; the piezoelectric ceramic 215 is installed in the mounting groove 212, and the piezoelectric ceramic 215 is located on the side of the motion actuator 213 away from the film 208.

[0085] When the piezoelectric ceramic 215 is energized, it deforms and drives the motion actuator 213 to move toward the film 208, thereby squeezing the film 208; alternatively, when the piezoelectric ceramic 215 is de-energized and restored to its original state, the second flexible hinge 214 recovers its deformation and drives the motion actuator 213 to move away from the film 208, thereby releasing the squeezing of the film 208.

[0086] Furthermore, the second flexible hinge 214 is formed on the substrate 201 by etching.

[0087] Specifically, in this embodiment, the second flexible hinge 214 is formed by using photolithography technology.

[0088] It should be understood that, based on the substrate 201 of PDMS material, the second flexible hinge 214 structure, the motion actuator 213 and the mounting groove 212 are formed by photolithography, and the vibration is transmitted to the motion actuator 213 through the piezoelectric ceramic 215. The motion actuator 213 is displaced by the driving force of the piezoelectric ceramic 215, and then the motion actuator 213 drives the film 208 to be pressed down, and the one-way valve arranged near the liquid inlet 203 and the liquid outlet 204 pushes the medicine liquid siphoned in and stored in the liquid storage cavity 211 of the film 208 toward the liquid outlet 204; because the motion actuator 213 has the second flexible hinge 214 structure, it can realize the reset function, and the film 208 opens, thereby continuing to absorb water from the liquid inlet 203, and so on, to achieve the purpose of continuous infusion of medicine.

[0089] The MEMS motion actuator 213 with a structure designed by driving the second flexible hinge 214 through the piezoelectric ceramic 215 is beneficial to improving the performance of the microfluidic pump 200 .

[0090] In some embodiments of the present invention, Fig. 9 and Fig.10 As shown, two mounting grooves 212 are provided on the base 201 , and the two mounting grooves 212 are located on two opposite sides of the film 208 ; driving mechanisms are installed in the two mounting grooves 212 .

[0091] By arranging the piezoelectric ceramic 215 drive and motion actuator 213 symmetrically up and down, it is helpful to compress the film 208 to a state where the upper and lower films 208 are tightly fitted, and it is helpful to replenish the complete liquid from the liquid inlet 203 to the liquid storage cavity 211 of the film 208 in time through the siphon effect, which is helpful to further improve the performance of the microfluidic pump 200.

[0092] The above is only a preferred specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily thought of by a person skilled in the art within the technical scope disclosed by the present invention should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.

Claims

1. A pressure detection system, characterized in that: include: a housing, wherein a cavity is formed in the housing; an elastic membrane, the elastic membrane being installed in the cavity to separate the cavity into a first chamber and a second chamber which are not connected to each other; a liquid inlet, the liquid inlet being opened on the shell and communicating with the first chamber and the outside of the shell; A first electrode sheet, the first electrode sheet is installed on a side of the elastic membrane facing the second chamber; a second electrode sheet, the second electrode sheet being installed in the second chamber, and the second electrode sheet being arranged opposite to the first electrode sheet; The first flexible hinge is formed on the elastic membrane, is in a ring shape, and is arranged around the first electrode sheet.

2. The pressure detection system according to claim 1, characterized in that: The elastic film is made of polydimethylsiloxane.

3. The pressure detection system according to claim 1 or 2, characterized in that: The elastic membrane has a first surface and a second surface facing each other. The elastic membrane forms a depression on the first surface and / or a depression on the second surface in a certain annular area to form the first flexible hinge.

4. The pressure detection system according to claim 3, characterized in that: The recess is formed on the elastic film by etching.

5. The pressure detection system according to claim 4, characterized in that: Also includes: An exhaust hole is provided on the shell and communicates with the second chamber and the outside of the shell.

6. A microfluidic pump, characterized in that: include: The pressure detection system according to any one of claims 1 to 5; A substrate, wherein a flow channel is formed on the substrate, and a liquid inlet and a liquid outlet are formed at two ends of the flow channel respectively; the pressure detection system is installed on the substrate; A pressure detection channel is formed on the substrate, one end of the pressure detection channel is connected to a side of the flow channel close to the liquid outlet, and the other end is connected to the liquid inlet.

7. The microfluidic pump according to claim 6, characterized in that: More than two pressure detection systems are installed on the substrate, and the liquid inlet of each pressure detection system is connected to the pressure detection channel. The liquid pressure when the first electrode sheet and the second electrode sheet of each pressure detection system are in contact is arranged in order from small to large.

8. The microfluidic pump according to claim 6, characterized in that: The flow channel includes a first flow channel and a second flow channel; The microfluidic pump also includes: A film, wherein the film is connected between the first flow channel and the second flow channel, a liquid storage cavity communicating with the first flow channel and the second flow channel is formed in the film, an end of the first flow channel away from the liquid storage cavity forms the liquid inlet, and an end of the second flow channel away from the liquid storage cavity forms the liquid outlet; A first one-way valve, which is installed in the first flow channel and is oriented from the liquid inlet to the liquid storage chamber; A second one-way valve, which is installed in the second flow channel, with the direction from the liquid storage chamber to the liquid outlet, and is located between the pressure detection channel and the liquid storage chamber; A driving mechanism is installed on the base, and is used to squeeze the film to pump out the liquid stored in the liquid storage chamber through the second flow channel, the second one-way valve, and the liquid outlet; or, release the squeezing of the film, the film recovers, the liquid storage chamber expands, and the external liquid is pumped in through the liquid inlet, the second flow channel, and the second one-way valve.

9. The microfluidic pump according to claim 8, characterized in that: The base is provided with a mounting groove, and the mounting groove is connected to the position of the film; The driving mechanism comprises: A motion actuator is installed in the installation slot; A second flexible hinge connects the motion actuator and the mounting slot; A piezoelectric ceramic is installed in the installation groove and is located on a side of the motion actuator away from the film; The piezoelectric ceramic is deformed when energized, driving the motion actuator to move toward the film, thereby squeezing the film; or, the piezoelectric ceramic is restored to its original state when power is turned off, and the second flexible hinge recovers its deformation and drives the motion actuator to move away from the film, thereby releasing the squeezing of the film.

10. The microfluidic pump according to claim 9, characterized in that: The base body has two mounting grooves, and the two mounting grooves are located on two opposite sides of the film; The driving mechanism is installed in both of the installation slots.

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