A micro-flow gas system and a micro-flow gas control method

Abstract

The present application discloses a micro-gas flow system and a micro-gas flow control method, which relate to the technical field of gas detectors. The method comprises a gas path system, a feedback and control circuit module, a communication interface module and a power supply module. The gas path system consists of a main gas path, a gas flow loop and an internal circulation loop. The main gas path is used to directly connect pure gas to a target detector. The gas flow loop is used to discharge the exhaust gas of the target detector to the atmosphere outside the system. The internal circulation loop is used to transport the exhaust gas of the target detector back to the system. The feedback and control circuit module is used to control the opening and closing of the main gas path, the gas flow loop and the internal circulation loop. The communication interface module is used to issue control instructions to the feedback and control circuit module and monitor the system status. The power supply module is used to supply power to the gas path system, the feedback and control circuit module, the communication interface module and the power supply module. The present application can greatly improve the gas utilization rate, extend the service life of the gas supply cylinder, and reduce the maintenance cost and operation complexity.

Description

Technical Field

[0001] The present application relates to the field of gas detection technology, and in particular to a micro-flow gas system and a micro-flow gas control method. Background Art

[0002] When the gas detector is working, the composition and purity of the internal gas must remain stable to ensure the stability of its performance. If a small amount of water molecules and oxygen molecules impurities are continuously released by various materials inside the gas chamber and accumulate for a long time, it will have a significant negative impact on the performance of the detector.

[0003] The traditional method uses a continuous flow of gas supply to ensure the long-term stability of the gas detector's performance by continuously renewing the internal working gas. However, this method leads to a large amount of gas waste, which not only increases the cost of use, but also increases the complexity of operation, thus severely limiting the application scope of gas detectors. Summary of the invention

[0004] The purpose of the present application is to provide a micro-gas flow system and a micro-gas flow control method, which can automatically switch between the gas flow mode and the internal circulation mode, improve the gas utilization rate, extend the gas use time, and reduce the maintenance cost and operation complexity.

[0005] To achieve the above objectives, this application provides the following solutions:

[0006] In a first aspect, the present application provides a microfluidic system, comprising:

[0007] Gas circuit system, feedback and control circuit module, communication interface module and power supply module; the gas circuit system consists of a main gas circuit, a gas flow loop and an internal circulation loop; the main gas circuit is used to directly connect pure gas to the target detector; the gas flow loop is used to discharge the exhaust gas of the target detector into the atmosphere outside the system; the internal circulation loop is used to transport the exhaust gas of the target detector back to the system; the feedback and control circuit module is used to control the opening and closing of the main gas circuit, the gas flow loop and the internal circulation loop; the communication interface module is used to issue control instructions to the feedback and control circuit module and monitor the system status based on user needs; the power supply module is used to supply power to the gas circuit system, feedback and control circuit module, communication interface module and power supply module.

[0008] Optionally, the gas in the main gas path in the gas path system passes through a mass flow meter, a first three-way solenoid valve and a pressure / temperature sensor in sequence and then enters the target detector; the mass flow meter is used to accurately control the input flow rate of the gas source gas; the first three-way solenoid valve is used to actively control the switching between the main gas path and the internal circulation loop, and the pressure / temperature sensor is used to monitor the internal temperature and pressure of the gas path.

[0009] Optionally, after the gas in the inner circulation loop in the gas path system is discharged from the target detector, it passes through the second three-way solenoid valve, the purification rod, the micro pump, the first three-way solenoid valve and the pressure / temperature sensor in sequence, and then re-enters the target detector; the second three-way solenoid valve is used to actively control the switching of the gas flow loop and the inner circulation loop; the purification rod is used to remove impurities in the inner circulation loop; the micro pump is used to maintain the gas flow in the inner circulation loop.

[0010] Optionally, the gas in the gas flow circuit in the gas path system is discharged from the target detector and sequentially passes through a second three-way solenoid valve and a float flowmeter before being discharged to the outside of the system; the float flowmeter is used to measure and display the flow of the discharged gas.

[0011] Optionally, the communication interface module uses RS485 standard to communicate with external devices.

[0012] Optionally, the feedback and control circuit module has a built-in slave server based on the Modbus protocol.

[0013] Optionally, control software is also included;

[0014] The control software uses the Modbus protocol to communicate with the microfluidic system; the control software is used to provide users with different working mode options, and is used for fine-tuning parameters of various components of the system and real-time monitoring of the operating status.

[0015] Optionally, the working modes include air flow mode, internal circulation mode and mixed mode; when the working mode is the air flow mode, the valve in the first three-way solenoid valve in the direction of micro pump-first three-way solenoid valve is closed, the valve in the direction of mass flow meter-first three-way solenoid valve-pressure / temperature sensor is opened, the valve in the second three-way solenoid valve-second three-way solenoid valve-purification rod direction is closed, and the valve in the direction of target detector-second three-way solenoid valve-float flowmeter direction is opened; when the working mode is the internal circulation mode, the valve in the first three-way solenoid valve in the direction of mass flow meter-first three-way solenoid valve is closed, the valve in the direction of micro pump-first three-way solenoid valve-pressure / temperature sensor is opened, the valve in the second three-way solenoid valve-second three-way solenoid valve-float flowmeter direction is closed, and the valve in the direction of target detector-second three-way solenoid valve-purification rod direction is opened.

[0016] Optionally, the mixed mode is to cyclically switch the air flow mode and the internal circulation mode at a set time ratio.

[0017] In a second aspect, the present application provides a microfluidic control method based on the microfluidic system, comprising:

[0018] Initialize the microfluidics system;

[0019] Start feedback and control circuit module;

[0020] Run the control software and establish a connection with the microfluidics system via the Modbus protocol;

[0021] According to the working mode selected by the user, the first three-way solenoid valve and the second three-way solenoid valve are controlled to complete the switching of the gas flow path, and the relevant gas path components are started / stopped at the same time to realize different functional modes; when the working mode is the gas flow mode, the valve in the direction of the micro pump-first three-way solenoid valve in the first three-way solenoid valve is closed, the valve in the direction of the mass flow meter-first three-way solenoid valve-pressure / temperature sensor is opened, the valve in the direction of the second three-way solenoid valve-purification rod in the second three-way solenoid valve is closed, and the valve in the direction of the target detector-second three-way solenoid valve-float flowmeter is opened. The valve is opened and the micro pump is turned off at the same time; when the working mode is the internal circulation mode, the valve in the direction of mass flow meter-first three-way solenoid valve in the first three-way solenoid valve is closed, the valve in the direction of micro pump-first three-way solenoid valve-pressure / temperature sensor is opened, the valve in the direction of second three-way solenoid valve-float flowmeter in the second three-way solenoid valve is closed, the valve in the direction of target detector-second three-way solenoid valve-purification rod is opened, and the micro pump is turned on at the same time; when the working mode is the mixed mode, the system automatically switches between the gas flow mode and the internal circulation mode at a time ratio preset by the user.

[0022] According to the specific embodiments provided in this application, this application discloses the following technical effects:

[0023] The present application provides a micro-flow gas system and a micro-flow gas control method, which includes a gas path system, a feedback control circuit module, a communication interface module and a power module; the gas path system consists of a main gas path, an exhaust cycle and an internal cycle; the main gas path is responsible for directly delivering pure gas to the target detector; the exhaust cycle discharges the exhaust gas of the target detector into the atmosphere outside the system; the internal cycle sends the exhaust gas back to the system; the feedback control circuit module controls the switches of the main gas path, the exhaust cycle and the internal cycle; the communication interface module sends control instructions to the feedback control circuit module according to user needs; the power module provides power for the gas path system, the feedback control circuit module, the communication interface module and itself. The present application can greatly improve the gas utilization rate, extend the service life of the gas supply cylinder, reduce maintenance costs and operation complexity, and provide the possibility for the long-term use of gas flow gas detectors in non-laboratory scenarios. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0025] Figure 1 A schematic structural diagram of a microfluidic system provided in one embodiment of the present application.

[0026] Figure 2 A physical diagram of a microfluidic system provided in accordance with an embodiment of the present application.

[0027] Figure 3 A schematic flow chart of a microfluidics control method provided in accordance with an embodiment of the present application. DETAILED DESCRIPTION

[0028] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0029] In order to make the above-mentioned objects, features and advantages of the present application more obvious and easy to understand, the present application is further described in detail below in conjunction with the accompanying drawings and specific implementation methods.

[0030] Embodiment 1

[0031] like Figure 1 The present embodiment provides a micro-gas flow system, comprising: a gas path system, a feedback and control circuit module, a communication interface module and a power supply module; the gas path system consists of a main gas path, a gas flow loop and an internal circulation loop; the main gas path is used to directly connect pure gas to the target detector; the gas flow loop is used to discharge the exhaust gas of the target detector into the atmosphere outside the system; the internal circulation loop is used to transport the exhaust gas of the target detector back to the system; the feedback and control circuit module is used to control the opening and closing of the main gas path, the gas flow loop and the internal circulation loop; the communication interface module is used to issue control instructions to the feedback and control circuit module and monitor the system status based on user needs; the power supply module is used to supply power to the gas path system, the feedback and control circuit module, the communication interface module and the power supply module.

[0032] Among them, Figure 1As shown, the gas in the main gas path in the gas path system passes through the mass flow meter, the first three-way solenoid valve and the pressure / temperature sensor in sequence, and then enters the target detector; the mass flow meter is used to accurately control the input flow rate of the gas source gas; the first three-way solenoid valve is used to actively control the switching of the main gas path and the internal circulation loop, and the pressure / temperature sensor is used to monitor the internal temperature and pressure of the gas path.

[0033] After being discharged from the target detector, the gas in the inner circulation loop in the gas path system passes through the second three-way solenoid valve, the purification rod, the micro pump, the first three-way solenoid valve and the pressure / temperature sensor in sequence, and then re-enters the target detector; the second three-way solenoid valve is used to actively control the switching between the gas flow loop and the inner circulation loop; the purification rod is used to remove impurities in the inner circulation loop; the micro pump is used to maintain the gas flow in the inner circulation loop.

[0034] The gas in the gas flow circuit in the gas path system is discharged from the target detector and sequentially passes through the second three-way electromagnetic valve and the float flowmeter before being discharged to the outside of the system; the float flowmeter is used to measure and display the flow of the discharged gas.

[0035] Specifically, the source gas is connected to the system through the Gas-Inlet; the pure gas is connected to the target detector directly from the outlet DI through the main gas line; the detector exhaust is connected back to the system through the DO port, and the system uses a three-way solenoid valve to control which branch gas line the reflux takes, thereby realizing two basic working states.

[0036] The communication interface module uses RS485 standard to communicate with external devices. The feedback and control circuit module has a built-in slave server based on Modbus protocol.

[0037] In some embodiments, control software is also included; the control software uses the Modbus protocol to communicate with the microfluidic system; the control software is used to provide users with different working mode options.

[0038] Among them, Figure 1As shown, the working modes include air flow mode, internal circulation mode and mixed mode; when the working mode is the air flow mode, the valve in the direction of the micro pump-first three-way solenoid valve in the first three-way solenoid valve is closed, the valve in the direction of the mass flow meter-first three-way solenoid valve-pressure / temperature sensor is opened, the valve in the direction of the second three-way solenoid valve-purification rod in the second three-way solenoid valve is closed, and the valve in the direction of the target detector-second three-way solenoid valve-float flowmeter is opened; when the working mode is the internal circulation mode, the valve in the direction of the mass flow meter-first three-way solenoid valve in the first three-way solenoid valve is closed, the valve in the direction of the micro pump-first three-way solenoid valve-pressure / temperature sensor is opened, the valve in the direction of the second three-way solenoid valve-float flowmeter in the second three-way solenoid valve is closed, and the valve in the direction of the target detector-second three-way solenoid valve-purification rod is opened.

[0039] That is, it is divided into a gas flow state and an internal circulation state. In the gas flow state, the gas passes through the float flowmeter and is directly discharged into the atmosphere. In the internal circulation state, the gas is purified by the purification rod and then returns to the main gas path, and finally supplies gas to the target detector again.

[0040] In addition, a mixed mode is also included, in which the air flow mode and the internal circulation mode are cyclically switched at a set time ratio. When the switching frequency is high, the mode can be approximated as a state of simultaneous air flow and internal circulation.

[0041] Embodiment 2

[0042] like Figure 3 As shown, this embodiment provides a microfluidic control method based on a microfluidic system, including:

[0043] Step 301: Initialize the microfluidic system.

[0044] Step 302: Start the feedback and control circuit module.

[0045] Step 303: Run the control software and establish a connection with the microfluidic system via the Modbus protocol.

[0046] Step 304: According to the working mode selected by the user, the first three-way solenoid valve and the second three-way solenoid valve are controlled to complete the switching of the gas flow path, and the relevant gas path components are started / stopped at the same time to realize different functional modes; when the working mode is the gas flow mode, the valve in the direction of the micro pump-first three-way solenoid valve in the first three-way solenoid valve is closed, the valve in the direction of the mass flow meter-first three-way solenoid valve-pressure / temperature sensor is opened, the valve in the direction of the second three-way solenoid valve-purification rod in the second three-way solenoid valve is closed, the target detector-second three-way solenoid valve-float flowmeter The valve in the direction is opened, and the micro pump is turned off at the same time; when the working mode is the internal circulation mode, the valve in the direction of the mass flow meter-first three-way solenoid valve in the first three-way solenoid valve is closed, the valve in the direction of the micro pump-first three-way solenoid valve-pressure / temperature sensor is opened, the valve in the direction of the second three-way solenoid valve-float flowmeter in the second three-way solenoid valve is closed, the valve in the direction of the target detector-second three-way solenoid valve-purification rod is opened, and the micro pump is turned on at the same time; when the working mode is the mixed mode, the system automatically switches between the gas flow mode and the internal circulation mode at a time ratio preset by the user.

[0047] The present application also provides a specific embodiment of a microfluidic control method, the content of which is as follows:

[0048] In this embodiment, two different situations are considered: one involving the use of a microfluidic system and the other not. Figure 2 As shown in the figure, a small gas cylinder with a capacity of 500mL and a pressure of 10MPa is used. The specific conditions are as follows: the gas flow rate is 10ccm, and the time allocation in the mixed mode is a ratio of gas flow to gas holding of 1:10; the pump running speed is set to 30%. After testing, it is found that after using the micro-flow system, the equipment can operate for three months. Without using this system, a large gas cylinder with a capacity of 40L and a pressure of 5MPa is selected. The specific conditions are: the gas flow rate is 40ccm, and the service life is also three months. By comparing the test results of these two cases, it can be found that since this system can automatically switch to the gas flow mode and the internal circulation mode according to the actual use needs of the gas detector, it can effectively improve the use efficiency of the gas and extend its service life. Therefore, only a small gas cylinder with a smaller volume of 500mL@10MPa is needed to meet the long-term operation requirements of the micro-flow system.

[0049] In summary, this application has the following technical effects:

[0050] The microflow system and microflow control method provided in the present application can automatically switch the gas flow mode and the internal circulation mode according to the use requirements of the gas detector, effectively improve the gas utilization rate, extend the gas use time, reduce maintenance costs and operation complexity, and expand the application scenarios of the gas detector.

[0051] The technical features of the above embodiments may be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0052] This article uses specific examples to illustrate the principles and implementation methods of this application. The description of the above embodiments is only used to help understand the method and core ideas of this application. At the same time, for those skilled in the art, according to the ideas of this application, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as limiting this application.

Claims

1. A microfluidic system, characterized in that: include: Gas circuit system, feedback and control circuit module, communication interface module and power supply module; the gas circuit system consists of a main gas circuit, a gas flow loop and an internal circulation loop; the main gas circuit is used to directly connect pure gas to the target detector; the gas flow loop is used to discharge the exhaust gas of the target detector into the atmosphere outside the system; the internal circulation loop is used to transport the exhaust gas of the target detector back to the system; the feedback and control circuit module is used to control the opening and closing of the main gas circuit, the gas flow loop and the internal circulation loop; the communication interface module is used to issue control instructions to the feedback and control circuit module and monitor the system status based on user needs; the power supply module is used to supply power to the gas circuit system, feedback and control circuit module, communication interface module and power supply module.

2. A microfluidic system according to claim 1, characterized in that: The gas in the main gas path in the gas path system passes through the mass flow meter, the first three-way solenoid valve and the pressure / temperature sensor in sequence, and then enters the target detector; the mass flow meter is used to accurately control the input flow rate of the gas source gas; the first three-way solenoid valve is used to actively control the switching between the main gas path and the internal circulation loop, and the pressure / temperature sensor is used to monitor the internal temperature and pressure of the gas path.

3. A microfluidic system according to claim 2, characterized in that: After being discharged from the target detector, the gas in the inner circulation loop in the gas path system passes through the second three-way solenoid valve, the purification rod, the micro pump, the first three-way solenoid valve and the pressure / temperature sensor in sequence, and then re-enters the target detector; the second three-way solenoid valve is used to actively control the switching between the gas flow loop and the inner circulation loop; the purification rod is used to remove impurities in the inner circulation loop; the micro pump is used to maintain the gas flow in the inner circulation loop.

4. A microfluidic system according to claim 3, characterized in that: The gas in the gas flow circuit in the gas path system is discharged from the target detector and sequentially passes through the second three-way electromagnetic valve and the float flowmeter before being discharged to the outside of the system; the float flowmeter is used to measure and display the flow of the discharged gas.

5. A microfluidic system according to claim 4, characterized in that: The communication interface module uses the RS485 standard to communicate with external devices.

6. A microfluidic system according to claim 5, characterized in that: The feedback and control circuit module has a built-in slave server based on the Modbus protocol.

7. A microfluidic system according to claim 6, characterized in that: Also includes control software; The control software uses the Modbus protocol to communicate with the microfluidic system; the control software is used to provide users with different working mode options, and is used for fine-tuning parameters of various components of the system and real-time monitoring of the operating status.

8. The microfluidic system according to claim 7, characterized in that: The working modes include gas flow mode, internal circulation mode and mixed mode; when the working mode is the gas flow mode, the valve in the direction of the micro pump-first three-way solenoid valve in the first three-way solenoid valve is closed, the valve in the direction of the mass flow meter-first three-way solenoid valve-pressure / temperature sensor is opened, the valve in the direction of the second three-way solenoid valve-purification rod in the second three-way solenoid valve is closed, and the valve in the direction of the target detector-second three-way solenoid valve-float flowmeter is opened; when the working mode is the internal circulation mode, the valve in the direction of the mass flow meter-first three-way solenoid valve in the first three-way solenoid valve is closed, the valve in the direction of the micro pump-first three-way solenoid valve-pressure / temperature sensor is opened, the valve in the direction of the second three-way solenoid valve-float flowmeter in the second three-way solenoid valve is closed, and the valve in the direction of the target detector-second three-way solenoid valve-purification rod is opened.

9. The microfluidic system according to claim 8, characterized in that: The mixed mode is to cyclically switch the air flow mode and the internal circulation mode at a set time ratio.

10. A microfluidic control method of a microfluidic system according to any one of claims 1 to 9, characterized in that: include: Initialize the microfluidics system; Start feedback and control circuit module; Run the control software and establish a connection with the microfluidics system via the Modbus protocol; According to the working mode selected by the user, the first three-way solenoid valve and the second three-way solenoid valve are controlled to complete the switching of the gas flow path, and the relevant gas path components are started / stopped at the same time to realize different functional modes; when the working mode is the gas flow mode, the valve in the direction of the micro pump-first three-way solenoid valve in the first three-way solenoid valve is closed, the valve in the direction of the mass flow meter-first three-way solenoid valve-pressure / temperature sensor is opened, the valve in the direction of the second three-way solenoid valve-purification rod in the second three-way solenoid valve is closed, and the valve in the direction of the target detector-second three-way solenoid valve-float flowmeter is opened. The valve is opened and the micro pump is turned off at the same time; when the working mode is the internal circulation mode, the valve in the direction of mass flow meter-first three-way solenoid valve in the first three-way solenoid valve is closed, the valve in the direction of micro pump-first three-way solenoid valve-pressure / temperature sensor is opened, the valve in the direction of second three-way solenoid valve-float flowmeter in the second three-way solenoid valve is closed, the valve in the direction of target detector-second three-way solenoid valve-purification rod is opened, and the micro pump is turned on at the same time; when the working mode is the mixed mode, the system automatically switches between the gas flow mode and the internal circulation mode at a time ratio preset by the user.

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