Full-feedback automatic control gas distribution system

Abstract

The utility model provides a full-feedback automatic control gas distribution system which comprises a standard gas cylinder group, the standard gas cylinder group is communicated with a test box, and the test box and the standard gas cylinder group are both communicated with a gas analysis module. Gas flow monitoring control modules are arranged between the standard gas cylinder group and the test box as well as between the standard gas cylinder group and the gas analysis module, and the test box, the gas analysis module and the gas flow monitoring control modules are all connected with the upper computer. According to the utility model, the gas analysis module, the gas flow monitoring control module and the upper computer are used for detecting the type and concentration of gas in the test box in real time and dynamically controlling the rate of the gas input into the test box, so that the type and concentration of the gas in the test box are adjusted, and automatic preparation of environment gas required by an experiment is realized; and the intelligent degree of the gas distribution system is improved.

Description

TECHNICAL FIELD

[0001] The utility model relates to the technical field of gas distribution system especially, relate to an automatic gas distribution system. BACKGROUND

[0002] When producing and calibrating the gas sensor, the gas concentration and temperature of the environment where the gas sensor is located need to be fixed to avoid abnormal calibration data of the gas sensor due to concentration or temperature fluctuation, thereby affecting the concentration output of the gas sensor.

[0003] In order to ensure the concentration output accuracy of each gas sensor, the calibration data of each gas sensor needs to be obtained during production, and these calibration data need to be obtained by preparing standard gas with different temperatures and different concentrations. The higher the accuracy of preparing standard gas with different temperatures and different concentrations, the more accurate the calibration data of the gas sensor obtained, and thus the concentration output accuracy of the gas sensor is more accurate.

[0004] The essence of gas sensor calibration is the mapping relationship between the original signal of the sensor under different temperatures and different concentrations and the calibration data. The existing automatic gas distribution system has limited gas concentration points, and can only prepare gas with standard gas concentration points, which can meet the production and use. In the research and development and testing process of the product, in addition to the zero point and SPAN point, the concentration between the zero point and the SPAN point also needs to be tested.

[0005] The combustible gas sensor is currently manually prepared, that is, the volume of pure combustible gas injected into the gas tank is calculated by calculating the volume of the gas tank, so as to realize the preparation of combustible gas with specified concentration. If the gas tank leaks, the concentration accuracy in the gas tank cannot be guaranteed. If the volume of gas injected into the gas tank is too much or too little, it will also cause the concentration in the gas tank to be too high or too low. These human interference factors are more.

[0006] The invention with publication number CN102425726B relates to a kind of comprehensive gas distribution device and gas distribution method of explosion-proof test of coal mine explosion-proof electric appliance, it sequentially from gas source unit, flow control unit, gas mixing device, test tank unit and pressure transmitter, gas analysis unit, data collector, computer composition, also include the programmable controller PLC control cabinet of flow control unit, test tank unit, pressure transmitter, gas analysis unit by computer control.The invention makes full use of modern means of programmable controller PLC process control, system can carry out real-time data acquisition and analysis in the process of gas distribution test, simultaneously, three-stage gas mixing device is used to make the accuracy and success rate of gas distribution high, system reaction speed is fast, degree of automation is high, gas distribution method ensures the accuracy and success rate of inspection, improves inspection efficiency on the basis of accuracy and success rate.However, the invention does not utilize fan to uniformly mix gas, which can easily cause uneven gas mixing, and the invention does not consider the experimental environment temperature, so the experimental application scenario is narrow.

[0007] The invention patent with publication number CN 1916599 B discloses a gas detector field calibration instrument and a gas distribution method, wherein the gas detector field calibration instrument comprises: a gas cylinder storing high-pressure component gas; a gas pressure stabilizing valve connected to the high-pressure gas cylinder through a gas transmission pipeline; a cover container; a high-speed quantitative electromagnetic valve connected to the component gas pressure stabilizing valve through a gas transmission pipeline and transmitting the component gas to the cover container; a microprocessor system electrically connected to the high-speed quantitative electromagnetic valve; and a power supply module for supplying power to the microprocessor and the high-speed quantitative electromagnetic valve. The gas detector field calibration instrument injects a certain volume of component gas into the container by controlling the opening and closing time and number of the quantitative electromagnetic valve, and detects the effectiveness of the gas alarm. The calibration instrument is small in size, powered by a battery, provides component gas with a miniature high-pressure gas cylinder, and can adapt to multiple component gases, with low power consumption and low cost. However, the field calibration instrument is mainly used for on-site gas concentration detection and does not provide a test chamber or other test site, so it cannot be used for sensor experiments. Practical new type content

[0008] To solve the technical problems of low intelligence and unstable gas distribution precision of existing gas distribution systems, the present application provides a full-feedback automatic gas distribution system with high stability, high precision and high expandability.

[0009] To achieve the above-mentioned purpose, the technical scheme of the present application is as follows: a full-feedback automatic control gas distribution system, comprising a standard gas cylinder group, the standard gas cylinder group being in communication with a test chamber, the test chamber and the standard gas cylinder group both being in communication with a gas analysis module, a gas flow monitoring and control module being arranged between the standard gas cylinder group and the test chamber and between the standard gas cylinder group and the gas analysis module, and the test chamber, the gas analysis module and the gas flow monitoring and control module all being connected to an upper computer.

[0010] The standard gas cylinder group comprises a point inspection gas cylinder and at least one gas preparation cylinder, the point inspection gas cylinder is communicated with the gas analysis module, the gas preparation cylinders are communicated with the test box through the air pipes, the electromagnetic valve IV is arranged between the point inspection gas cylinder and the gas analysis module, the electromagnetic valve IV is connected with the upper computer through the electromagnetic valve controller, and the gas preparation cylinder and the test box are provided with the gas flow monitoring control module.

[0011] The test box is a high-low temperature test box, the high-low temperature test box comprises a shell, a control chip, a temperature control module and a gas stirring module are arranged in the shell, the temperature control module and the gas stirring module are connected with the control chip, and the control chip is connected with the upper computer.

[0012] The gas stirring module is a circulating fan, the motor of the circulating fan is connected with the control chip.

[0013] The temperature control module comprises a temperature sensor, a heating module and a refrigeration module, the temperature sensor, the heating module and the refrigeration module are connected with the control chip, and the control chip is connected with the upper computer.

[0014] The gas flow monitoring control module comprises a gas preparation electromagnetic valve and a mass flow controller, the gas preparation cylinder, the gas preparation electromagnetic valve, the mass flow controller and the high-low temperature test box are sequentially communicated, the gas preparation electromagnetic valve is connected with the electromagnetic valve controller, and the electromagnetic valve controller and the mass flow controller are connected with the upper computer.

[0015] The control chip is connected with the upper computer through a network cable or a wireless signal.

[0016] The gas analysis module is an infrared gas analyzer, the standard gas cylinder group and the high-low temperature test box are communicated with an external gas analyzer, and the external gas analyzer is connected with the upper computer.

[0017] The control chip is an MCU chip.

[0018] The infrared gas analyzer, the mass flow controller and the electromagnetic valve controller are connected with the upper computer through an RS485 bus.

[0019] The beneficial effects of the present invention are as follows: the present invention utilizes a gas analysis module, a gas flow monitoring and control module, and a host computer to detect the type and concentration of gas in the test chamber in real time, dynamically controls the gas rate input into the test chamber, and then adjusts the type and concentration of gas in the test chamber, thereby realizing automatic preparation of the environmental gas required for the experiment, and improving the intelligence level of the gas distribution system. After the automatic gas distribution system is put into use, it is more convenient for R&D personnel to regularly conduct characteristic data experiments of sensors under different gas concentrations to prevent product performance fluctuations caused by batch differences of key components. At the same time, the present invention installs a refrigeration module and a heating module in the test chamber to simulate environments at different temperatures, so that the experimental environment is closer to the actual use scenario of the sensor. It can also simulate extreme environments and test the performance of the sensor in extreme environments. In addition, a circulating fan is installed in the test chamber to evenly mix the gas in the test chamber to prevent experimental errors caused by uneven gas mixing. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0021] Figure 1 It is a structural diagram of the present utility model.

[0022] Figure 2 This is a schematic diagram of the connection relationship of the present utility model.

[0023] In the figure, 1 is a standard gas cylinder group, 11 is a standard gas cylinder I, 12 is a standard gas cylinder II, 13 is a standard gas cylinder III, 2 is a high and low temperature test chamber, 3 is an infrared gas analyzer, 4 is a solenoid valve I, 5 is a solenoid valve II, 6 is a solenoid valve III, 7 is a solenoid valve IV, 8 is a mass flow controller I, 9 is a mass flow controller II, 10 is a mass flow controller III, and 14 is a circulation fan. DETAILED DESCRIPTION

[0024] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0025] Example 1

[0026] like Figure 1As shown, a full feedback automatic control gas preparation system includes a standard gas cylinder group 1, the standard gas cylinder group 1 is communicated with a test box, the test box and the standard gas cylinder group 1 are communicated with a gas analysis module, the gas flow monitoring control module is arranged between the standard gas cylinder group 1 and the test box and between the standard gas cylinder group 1 and the gas analysis module, and the test box, the gas analysis module and the gas flow monitoring control module are connected with an upper computer by using an RS485 bus.

[0027] The standard gas cylinder group 1 is usually composed of a plurality of standard gas cylinders, usually includes a nitrogen cylinder, a pure gas cylinder and a plurality of standard gas cylinders with different concentrations, and the standard gas cylinder group 1 is mainly used to provide standard concentration gas with known gas type and known concentration. The gas analysis module is mainly used to detect the gas composition and concentration in the test box in real time during the preparation of the gas, and transmit the detection result to the upper computer to determine whether the gas concentration in the test box meets the standard. The gas analysis module can select an infrared gas analyzer 3. The test box is mainly used to contain the gas required for sensor experiment, and provides an experimental environment with accurate temperature and gas concentration for sensor experiment.

[0028] Embodiment 2

[0029] A full feedback automatic control gas preparation system, as shown Figure 2 Specifically, the standard gas cylinder group 1 includes a point inspection gas cylinder and at least one gas preparation cylinder, the point inspection gas cylinder is communicated with the infrared gas analyzer 3, the gas preparation cylinder is communicated with the test box through an air pipe, the electromagnetic valve IV 7 is arranged between the point inspection gas cylinder and the infrared gas analyzer 3, the electromagnetic valve IV 7 is connected with the upper computer through the electromagnetic valve controller, the gas flow monitoring control module is arranged between the gas preparation cylinder and the test box, and the electromagnetic valve controller is connected with the upper computer through the RS485 bus.

[0030] The point inspection gas cylinder is mainly used to output gas with known concentration to the infrared gas analyzer 3, and the infrared gas analyzer 3 uses the gas with known concentration to determine whether the test result of the infrared gas analyzer 3 on the gas concentration is accurate. The infrared gas analyzer 3 is provided with a gas outlet and a gas inlet, the gas inlet of the infrared gas analyzer 3 is connected with the test box through a hollow hose, and the gas outlet of the infrared gas analyzer 3 is arranged in the external environment to facilitate the discharge of gas. The gas preparation cylinder is mainly used to provide fixed concentration gas for gas preparation experiment, and usually includes a nitrogen cylinder, a pure gas cylinder and a plurality of standard gas cylinders with different concentrations. The electromagnetic valve IV 7 is closed when the infrared gas analyzer 3 is inspected to prevent the gas in the test box from entering the infrared gas analyzer 3 and affecting the inspection result and causing misjudgment.

[0031] The test box is a high-low temperature test box 2, which comprises a shell, a control chip, a temperature control module and a gas stirring module arranged in the shell, the temperature control module and the gas stirring module are connected with the control chip, the control chip is connected with the upper computer by network cable or wireless signal, and the wireless signal can be selected from WiFi signal, Bluetooth signal and the like. The use of the high-low temperature test box 2 can provide a sealed experimental environment for sensor experiments, and ensure that the gas composition, gas concentration and temperature in the test box are relatively stable during the experiment.

[0032] The shell is mainly used for providing a closed space for sensor experiments. The control chip is mainly used for receiving information from the upper computer and controlling the gas stirring module and the temperature control module according to the information. The temperature control module comprises a temperature sensor, a heating module and a refrigeration module, and the temperature sensor, the heating module and the refrigeration module are connected with the control chip. During use, the temperature sensor collects the temperature information in the high-low temperature test box 2 in real time, and transmits the temperature information to the upper computer through the control chip. The upper computer controls the heating module to generate heat or controls the refrigeration module to refrigerate according to the required temperature of the experiment, so that the temperature in the high-low temperature test box 2 is maintained at the required temperature of the sensor experiment. The temperature sensor can be selected from a PT100 temperature sensor, the heating module can be selected from a graphene heating module, and the refrigeration module can be selected from a TEC small refrigeration module.

[0033] The gas stirring module can be selected from a circulating fan 14, which is arranged on the side of the inner side of the shell. A gap is arranged between the circulating fan 14 and the side of the inner side of the shell. The motor of the circulating fan 14 is connected with the control chip, and the rotating of the circulating fan 14 is controlled by the control chip. The circulating fan 14 is mainly used for disturbing the gas in the high-low temperature test box 2, so that the gas in the high-low temperature test box 2 is fully and uniformly mixed, and the different densities of the gas in different regions of the high-low temperature test box 2 are prevented, so as to affect the experimental results of the sensor.

[0034] The gas preparation cylinder is connected with the test box through a hollow hose, and the gas flow monitoring and control module is arranged on the hollow hose. The gas flow monitoring and control module comprises a gas preparation electromagnetic valve and a mass flow controller. The other end of the hollow hose connected with the gas outlet of the gas preparation cylinder is connected with the gas inlet of the gas preparation electromagnetic valve. The gas outlet of the gas preparation electromagnetic valve is connected with the gas inlet of the mass flow controller through the hollow hose. The gas outlet of the mass flow controller is connected with the gas inlet of the high-low temperature test box 2 through the hollow hose. The gas preparation electromagnetic valve is connected with the electromagnetic valve controller, the mass flow controller is connected with the upper computer, and the electromagnetic valve controller is connected with the upper computer. The gas flow monitoring and control module is mainly used for monitoring the volume of various standard gases input into the high-low temperature test box 2 in real time, and controlling the flow of the standard gas according to the instruction of the upper computer.

[0035] The other structures and principles are the same as those of embodiment 1.

[0036] Example 3

[0037] A method of using a full feedback automatic control gas distribution system is:

[0038] like Figure 1 As shown, the gas preparation cylinders include standard gas cylinder I 11 and standard gas cylinder II 12, the inspection gas cylinders include standard gas cylinder III 13, and the gas preparation solenoid valves include solenoid valve I 4 and solenoid valve II 5. The gases in standard gas cylinders I 11, II 12, and III 13 are all of known type and concentration.

[0039] First, perform a spot check on the infrared gas analyzer 3. An inspection command is input to the host computer, which, through the solenoid valve controller, controls solenoid valve IV 7 to close the gas transmission channel from the high-temperature test chamber 2 to the infrared gas analyzer 3. Simultaneously, the host computer, through the solenoid valve controller, maintains the closed state of solenoid valves I 4 and II 5, while controlling solenoid valve III 6 and mass flow controller III 10 to open. This allows the gas in standard gas cylinder III 13 to enter the infrared gas analyzer 3 under the control of mass flow controller III 10. Mass flow controller III 10 is primarily used to prevent a large amount of gas from entering the high-temperature test chamber 2 all at once. Infrared gas analyzer 3 detects the type and concentration of the gas in standard gas cylinder III 13 and transmits the test results to the host computer. The host computer compares the test results of infrared gas analyzer 3 with the exact type and concentration of the gas in standard gas cylinder III 13 to determine whether the test results of infrared gas analyzer 3 are accurate. If not, technicians will need to adjust the settings of infrared gas analyzer 3 until the test results of infrared gas analyzer 3 are consistent with the exact type and concentration of the gas in standard gas cylinder III 13. After the inspection of infrared gas analyzer 3 is completed, the host computer closes solenoid valve III 6 through the solenoid valve controller.

[0040] Subsequently, the gas concentration and temperature within the high and low temperature test chamber 2 are adjusted. The host computer inputs the required experimental environment information based on the temperature, gas type, and concentration of each gas. This information includes the temperature of the high and low temperature test chamber 2, the gas type, and concentration corresponding to the corresponding gas cylinder. The host computer controls the high and low temperature test chamber 2 to adjust the temperature based on the required experimental environment information and the actual information of the high and low temperature test chamber 2, and adjusts the gas concentration by controlling the gas flow monitoring control module.

[0041] The method for adjusting temperature is that the host computer collects real-time temperature information collected by the temperature sensor and the required temperature of the experiment, and when the real-time temperature is lower than the required temperature of the experiment, the host computer starts the heating module to increase the temperature through the control chip until the real-time temperature reaches the required temperature of the experiment.

[0042] The method for adjusting the gas concentration is that the host computer controls the electromagnetic valve I 4 and the electromagnetic valve II 5 to be opened through the electromagnetic valve controller, and controls the flow rates of the gas in the standard gas cylinder I 11 and the standard gas cylinder II 12 through the mass flow controller I 8 and the mass flow controller II 9, so that the two kinds of gas enter the high-low temperature test box 2 at a fixed ratio within a certain time. The host computer controls the circulating fan 14 to rotate through the control chip, so that the gas entering the high-low temperature test box 2 is uniformly mixed. At the same time, the host computer controls the electromagnetic valve IV 7 to be opened through the electromagnetic valve controller, so that the gas in the high-low temperature test box 2 enters the infrared gas analyzer 3, and the infrared gas analyzer 3 is used to analyze the gas in the high-low temperature test box 2 in real time. When the types of the gas in the high-low temperature test box 2 and the concentration of each gas type reach the required environmental requirements of the experiment, the host computer controls the electromagnetic valve I 4, the electromagnetic valve II 5 and the electromagnetic valve IV 7 to be closed. When the concentration and the temperature of the gas in the high-low temperature test box 2 reach the required environmental requirements of the experiment, the host computer displays that the environment meets the standard, and the experimenters can start the experiment.

[0043] The other structures and principles are the same as those of embodiment 2.

[0044] The above only describes the preferred embodiments of the present application, and is not used to limit the present application. Any modification, equivalent replacement, improvement, etc. made within the spirit and principles of the present application shall be included in the protection scope of the present application.

Claims

1. A full feedback automatic control gas distribution system, characterized in that: The invention comprises a standard gas cylinder group (1), the standard gas cylinder group (1) is connected to a test box, the test box and the standard gas cylinder group (1) are both connected to a gas analysis module, a gas flow monitoring and control module is provided between the standard gas cylinder group (1) and the test box and between the standard gas cylinder group (1) and the gas analysis module, and the test box, the gas analysis module and the gas flow monitoring and control module are all connected to a host computer.

2. The full feedback automatic control gas distribution system according to claim 1, characterized in that: The standard gas cylinder group (1) includes a spot inspection gas cylinder and at least one gas preparation gas cylinder, the spot inspection gas cylinder is connected to the gas analysis module, the gas preparation gas cylinders are connected to the test box through a vent pipe, a solenoid valve IV (7) is provided between the spot inspection gas cylinder and the gas analysis module, the solenoid valve IV (7) is connected to the host computer through a solenoid valve controller, and a gas flow monitoring and control module is provided between the gas preparation gas cylinder and the test box.

3. The full feedback automatic control gas distribution system according to claim 2, characterized in that: The test chamber is a high and low temperature test chamber (2), which comprises a shell, a control chip, a temperature control module and a gas stirring module arranged in the shell, the inspection gas cylinder, the gas preparation gas cylinder and the gas analysis module are all connected to the shell through a ventilation pipe, the temperature control module and the gas stirring module are both connected to the control chip, and the control chip is connected to a host computer.

4. The full feedback automatic control gas distribution system according to claim 3, characterized in that: The gas stirring module is a circulation fan (14), which is arranged on the side surface inside the housing, and a motor of the circulation fan (14) is connected to a control chip.

5. The full feedback automatic control gas distribution system according to claim 3 or 4, characterized in that: The temperature control module includes a temperature sensor, a heating module and a cooling module. The temperature sensor, the heating module and the cooling module are all connected to a control chip, and the control chip is connected to a host computer.

6. The full feedback automatic control gas distribution system according to claim 5, characterized in that: The gas flow monitoring and control module includes a gas preparation solenoid valve and a mass flow controller. The gas preparation cylinder, the gas preparation solenoid valve, the mass flow controller and the high and low temperature test chamber (2) are connected in sequence. The gas preparation solenoid valve is connected to the solenoid valve controller. The solenoid valve controller and the mass flow controller are both connected to the host computer.

7. The full feedback automatic control gas distribution system according to claim 6, characterized in that: The control chip is connected to the host computer via a network cable or a wireless signal.

8. The full feedback automatic control gas distribution system according to claim 7, characterized in that: The gas analysis module is an infrared gas analyzer (3), the standard gas cylinder group (1) and the high and low temperature test box (2) are both connected to the infrared gas analyzer (3), and the external gas analyzer (3) is connected to the host computer.

9. The full feedback automatic control gas distribution system according to claim 8, characterized in that: The control chip is an MCU chip.

10. The full feedback automatic control gas distribution system according to claim 8 or 9, characterized in that: The infrared gas analyzer (3), mass flow controller and solenoid valve controller are all connected to the host computer via the RS485 bus.

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