A precise liquid volume control system for microfluidic chamber driving

Abstract

The present invention discloses a liquid volume precision control system driven by a microfluidic cavity, which is mainly composed of a liquid storage area, a liquid inlet area, and a liquid outlet area; the liquid storage area is composed of a liquid storage cavity and a microchannel, the liquid inlet area is composed of a microchannel, a one-way valve, an onboard microfluidic pump, and a liquid inlet pipe, and the liquid outlet area is composed of a liquid outlet pipe, a microchannel, a one-way valve, a capillary channel, and an onboard microfluidic pump, and the liquid storage area is connected to the liquid inlet area and the liquid outlet area. The present invention can achieve precise control of micron-level liquid volume in both the liquid inlet and the liquid outlet, so as to improve control accuracy and response speed, while reducing system complexity and maintenance costs.

Description

Technical Field

[0001] The present invention relates to a liquid volume precision control system for micro-liquid chamber driving. Background Art

[0002] Currently, sub-centimeter-scale catheter robots are widely used in procedures such as vascular intervention. These interventional catheter robots typically feature multiple microfluidic chambers to enable motions such as bending and retraction. Existing liquid volume control systems driven by microfluidic chambers generally suffer from low control accuracy and slow response speed. Because microfluidic chambers are relatively small, sometimes only reaching the milliliter level, precise liquid volume control is needed to improve the precise deformation of the microfluidic chambers. This can effectively enhance the operational precision of catheter robots and lay the foundation for further precision operation in interventional surgical environments. Currently, fluid chamber actuation for soft robots relies primarily on mechanical pumps or solenoid valves. These devices are prone to pressure fluctuations during operation, making precise liquid volume control difficult. However, these devices are large, making them difficult to precisely control and drive deformation of tiny liquid chambers. Precise liquid volume control typically requires the addition of complex buffering devices, such as rubber bladders or buffer screws, to reduce pressure fluctuations. Furthermore, precise liquid volume control in two different flow directions—high-pressure to low-pressure and low-pressure to high-pressure—is challenging, necessitating the design of separate devices to achieve this goal. Summary of the Invention

[0003] In order to solve the problems existing in the above-mentioned prior art, the present invention proposes a liquid volume precision control system for micro-liquid chamber drive, which can achieve precise control of liquid volume at the micron level both in liquid inlet and outlet, so as to improve control accuracy and response speed, while reducing system complexity and maintenance costs, and has important practical application value.

[0004] The present invention can be implemented through the following technical solutions:

[0005] A precise liquid volume control system for micro-liquid cavity drive, the system mainly consists of three parts: a liquid storage area, a liquid inlet area, and a liquid outlet area; the liquid storage area consists of a liquid storage cavity and a microchannel, the liquid inlet area consists of a microchannel, a one-way valve, an onboard microfluidic pump, and a liquid inlet pipe, and the liquid outlet area consists of a liquid outlet pipe, a microchannel, a one-way valve, a capillary channel, and an onboard microfluidic pump, and the liquid storage area is connected to the liquid inlet area and the liquid outlet area;

[0006] When liquid is inletted, the onboard microfluidic pump in the liquid outlet area is in a closed state, and the onboard microfluidic pump in the liquid inlet area is in an open state to act as a power device. The liquid flows from the liquid storage chamber through the microchannel, the one-way valve, the onboard microfluidic pump in the liquid inlet area, the one-way valve, and the liquid inlet pipe to the working area in a high-pressure state.

[0007] When discharging liquid, the onboard microfluidic pump in the liquid inlet area is in a closed state, and the onboard microfluidic pump in the liquid outlet area is in an open state to act as a power device. When the onboard microfluidic pump in the liquid outlet area is working, the liquid first flows from the high-pressure working area through the liquid outlet pipe and the microchannel to the capillary channel. The onboard microfluidic pump in the liquid outlet area continuously pumps the liquid flowing out of the capillary channel to the liquid storage chamber until the volume of the discharged liquid reaches the expected liquid discharge volume, thereby realizing accurate flow output of the liquid.

[0008] Furthermore, the liquid volume precision control system is a microfluidic chip made of non-metallic materials, and the microchannel is a tiny channel inside the chip that allows liquid to flow.

[0009] Furthermore, the liquid storage cavity is communicated with the atmosphere, and has holes at the bottom connected to the liquid inlet area and the liquid outlet area respectively.

[0010] Furthermore, the one-way valve is a microchannel with a specific structural form, which is in the form of a Tesla one-way valve structure, allowing liquid to flow in only one direction.

[0011] Furthermore, the internal rotor is driven by the electric motor to rotate unidirectionally. The onboard microfluidic pump is a peristaltic pump, which acts as a power device and a switching device at the same time. There is a soft pipe inside it. The internal rotor is driven by the electric motor to rotate unidirectionally. The internal rotor is continuously squeezed and relaxed. After combining with the one-way valve, the liquid flow in the soft pipe acts as a power device; when the internal rotor selects the squeeze state and the relaxation state, it acts as a switching device.

[0012] Furthermore, the capillary channel is a flow channel with a smaller flow channel width than the microchannel and is distributed in a tortuous manner. The function of the capillary channel is to balance the high-pressure state of the working area when the liquid is discharged, slow down the unit time flow rate of the liquid when it flows from high pressure to low pressure, and facilitate the onboard micro-flow pump in the liquid outlet area to control the precise flow output of the liquid.

[0013] Compared with the prior art, the present invention has the following advantages:

[0014] 1) High control precision: This system adopts advanced micro-control technology, which can achieve precise control of liquid volume and meet the precision requirements of micron level. It is particularly suitable for occasions requiring high-precision liquid delivery.

[0015] 2) Fast response: Through optimized drive mechanism and control system design, the system can quickly respond to changes in liquid volume, reduce delays, and improve the dynamic response performance of the overall system;

[0016] 3) High integration: The system is small in size and compact in design, integrating key control components and drivers into a miniaturized module, making it easy to install and deploy, and suitable for various space-limited application scenarios;

[0017] 4) Wide range of applications: This system is not only suitable for biomedical testing, drug screening and other fields, but can also be used in chemical analysis, environmental monitoring and other application scenarios, with broad market prospects and application value. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a schematic diagram of the overall structure of the present invention;

[0019] Figure 2 This is a schematic diagram of the extrusion state of the onboard microfluidic peristaltic pump of the present invention;

[0020] Figure 3 This is a schematic diagram of the relaxed state of the onboard microfluidic peristaltic pump of the present invention;

[0021] Figure 4 This is a schematic diagram of the working principle of the present invention;

[0022] Figure 5 Schematic diagram of the working principle of the liquid outlet area of ​​the present invention.

[0023] Figure 1 、 Figure 4 The bid number is as follows:

[0024] 1. Liquid storage chamber, 2. Microchannel, 3. One-way valve, 4. Onboard microfluidic pump, 5. Liquid inlet pipe, 6. Liquid outlet pipe, 7. Capillary channel, 8. Microfluidic pump chip substrate.

[0025] Figure 2 、 Figure 3 The bid number is as follows:

[0026] 41. Box, 42. Rotor, 43. Rotating plate, 44. Hose DETAILED DESCRIPTION

[0027] The following describes the embodiments of the present invention through specific embodiments. Those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification.

[0028] like Figure 1-5 As shown, the present invention is a precise liquid volume control system driven by a micro-liquid cavity, which consists of three parts: a liquid storage area, a liquid inlet area, and a liquid outlet area. The liquid storage area consists of a liquid storage cavity 1 and a microchannel 2, and the liquid inlet area can supply the liquid in the liquid storage area to the working area through the microchannel 2. The liquid inlet area consists of a microchannel 2, a one-way valve 3, an onboard microfluidic pump 4, and a liquid inlet pipe 5. When the onboard microfluidic pump 4 is working, the motor is located in the box 41, and the motor rotates to drive the rotating plate 43 to rotate in a circle. At this time, the rotor 42 on the rotating plate 43 will continuously squeeze the hose 44, that is, Figure 2 Figure 3The two states are alternated, causing the liquid to flow forward. Figure 2 When the squeezed state is fixed, it acts as a shut-off switch to prevent the flow of liquid. Figure 3 When the relaxed state is fixed, the liquid can flow. When the internal rotor 42 is continuously squeezed and relaxed, combined with the one-way valve 3, the liquid in the soft pipe can flow, which acts as a power device; when the internal rotor 42 chooses the squeeze and relaxation state, it can act as a switching device. When liquid is entering the liquid inlet area, the onboard micro-fluidic pump 4 in the liquid outlet area is in the closed state, and the onboard micro-fluidic pump 4 in the liquid inlet area is in the open state and acts as a power device. The liquid passes through the microchannel 2, the one-way valve 3, the onboard micro-fluidic pump 4 in the liquid inlet area, and the one-way valve 3 from the liquid storage chamber 1, and flows along the liquid inlet pipe 5 to the working area in the high-pressure state. Due to the closure of the liquid outlet area and the existence of the one-way valve 3 in the liquid inlet area, the liquid will continuously flow from the liquid storage chamber in the low-pressure state to the working area in the high-pressure state. The liquid discharge area consists of a liquid discharge pipe 6, microchannel 2, one-way valve 3, capillary channel 7, and an onboard microfluidic pump 4. During liquid discharge, the onboard microfluidic pump 4 in the liquid inlet area is closed, while the onboard microfluidic pump 4 in the liquid discharge area is open, acting as a power unit. When the onboard microfluidic pump 4 in the liquid discharge area is operating, liquid first flows from the high-pressure working area through the liquid discharge pipe 6 and microchannel to the capillary channel 7. The capillary channel 7 reduces the liquid flow rate per unit time. The onboard microfluidic pump 4 in the liquid discharge area continuously pumps liquid flowing out of the capillary channel 7 into the liquid storage chamber until the volume of liquid discharged reaches the desired output, achieving precise liquid flow output. Through micro-scale fluid volume manipulation, fine adjustment of the hydraulic pressure and deformation of the robot cavity is achieved. Among them, for the infusion and drainage under large hydraulic threshold, a micropump is constructed by pressing the flexible microcavity with a peristaltic pump, and combined with a planar one-way valve such as a Tesla valve, the fluid is pumped in one direction to the microcavity array; the pressure reduction characteristics of the capillary tube and the unique switching characteristics of the peristaltic pump are used to achieve precise control of liquid volume discharge.

[0029] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A precise liquid volume control system for microfluidic chamber drive, characterized in that: The system consists of three parts: a liquid storage area, a liquid inlet area, and a liquid outlet area; the liquid storage area consists of a liquid storage cavity and a microchannel; the liquid inlet area consists of a microchannel, a one-way valve, an onboard microfluidic pump, and a liquid inlet pipe; the liquid outlet area consists of a liquid outlet pipe, a microchannel, a one-way valve, a capillary channel, and an onboard microfluidic pump; the liquid storage area is connected to both the liquid inlet area and the liquid outlet area; When liquid is inletted, the onboard microfluidic pump in the liquid outlet area is in a closed state, and the onboard microfluidic pump in the liquid inlet area is in an open state to act as a power device. The liquid flows from the liquid storage chamber through the microchannel, the one-way valve, the onboard microfluidic pump in the liquid inlet area, the one-way valve, and the liquid inlet pipe to the working area in a high-pressure state. When discharging liquid, the onboard microfluidic pump in the liquid inlet area is in a closed state, and the onboard microfluidic pump in the liquid outlet area is in an open state to act as a power device. When the onboard microfluidic pump in the liquid outlet area is working, the liquid first flows from the high-pressure working area through the liquid outlet pipe and the microchannel to the capillary channel. The onboard microfluidic pump in the liquid outlet area continuously pumps the liquid flowing out of the capillary channel to the liquid storage chamber until the volume of the discharged liquid reaches the expected liquid discharge volume. The capillary channel is a flow channel with a smaller flow channel width than the microchannel and is distributed in a tortuous manner. The function of the capillary channel is to balance the high-pressure state of the working area during liquid discharge, slow down the unit time flow rate of the liquid when it flows from high pressure to low pressure, and achieve accurate flow output of the liquid; The onboard microfluidic pump is a peristaltic pump that acts as both a power device and a switching device. It has a soft pipe inside, and the internal rotor is driven by an electric motor to rotate in one direction. The internal rotor continuously squeezes and relaxes. After combining with a one-way valve, the liquid flow in the soft pipe acts as a power device; when the internal rotor selects the squeeze state or the relaxation state, it acts as a switching device.

2. The liquid volume precision control system for microfluidic chamber drive according to claim 1, characterized in that: The liquid volume precision control system is a microfluidic chip made of non-metallic materials, and the microchannel is a tiny channel inside the chip that allows liquid to flow.

3. The liquid volume precision control system for microfluidic chamber drive according to claim 1, characterized in that: The liquid storage cavity is communicated with the atmosphere, and has holes at the bottom which are respectively connected with the liquid inlet area and the liquid outlet area.

4. The liquid volume precision control system for microfluidic chamber drive according to claim 1, characterized in that: The one-way valve is a microchannel with a Tesla one-way valve structure.

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