A gas detection calibration cabinet and self-calibration method

Abstract

The present invention proposes a gas detection calibration cabinet and a self-calibration method. The gas detection calibration cabinet includes multiple gas storage and delivery devices, an industrial computer and multiple gas grid groups; wherein the control signal output end of the industrial computer is connected to the control signal input end of the gas storage and delivery device; the gas outlet of the gas storage and delivery device is connected to the gas inlet of the gas grid group through a pipeline. The automatic calibration method includes placing the gas detector to be calibrated in the gas grid, controlling the zeroing standard gas to zero the gas grid through the industrial computer, and completing the zeroing adjustment of the gas detector to be calibrated; when the gas grid is in the zeroing state of the gas concentration to be calibrated, the industrial computer controls the calibration standard gas corresponding to the gas type to be calibrated to enter the gas grid according to the gas type to be calibrated of the gas detector to be calibrated, so that the gas detector to be calibrated completes automatic calibration.

Description

Technical Field

[0001] The invention provides a gas detection calibration cabinet and a self-calibration method, belonging to the technical field of automatic calibration of a gas detector to be calibrated. Background Art

[0002] Industrial hazardous gas detection is a necessary safety measure for some factories. The current hazardous gas detectors to be calibrated are based on the principle of Yuanxue reaction. As the use time increases, the gas detectors to be calibrated will have deviations, so the deviation of the equipment needs to be calibrated regularly. The calibration equipment on the market is currently single-device calibration. Although the deviation of the equipment can be compensated, it requires special personnel to operate, and the calibration process is complicated and time-consuming. Summary of the invention

[0003] The present invention provides a gas detection calibration cabinet and a self-calibration method to solve the above technical problems in the prior art. The technical solutions adopted are as follows:

[0004] A gas detection calibration cabinet, comprising a plurality of gas storage and delivery devices, an industrial computer and a plurality of gas grid groups; wherein a control signal output end of the industrial computer is connected to a control signal input end of the gas storage and delivery device; a gas outlet of the gas storage and delivery device is connected to a gas inlet of the gas grid group through a pipeline;

[0005] The industrial computer is used to control the gas flow rate of the gas storage and delivery device, and to control the operation of the gas grid group;

[0006] The gas storage and delivery device is used to input the input gas into a corresponding column of gas grid groups according to the gas flow rate determined by the industrial computer;

[0007] The gas grid group is used to accommodate the gas detector to be calibrated, and automatically calibrate the gas detector by respectively inputting the zeroing standard gas and the calibration standard gas.

[0008] Furthermore, the gas storage and delivery device includes a plurality of gas storage tanks corresponding to a plurality of input gases; each of the gas storage tanks is used to store a single input gas, and the input gas includes a zeroing gas and a calibration gas; wherein the output sides of the plurality of gas storage tanks are aggregated to a first aggregate pipeline, the output side of the first aggregate pipeline is connected to the main calibration pipeline through a first connecting pipeline, and a pressure reducing valve and a first normally closed control valve are provided between the output side of each gas storage tank and the first aggregate pipeline;

[0009] A flow regulating valve and a second normally closed control valve are arranged on the first connecting pipeline accordingly;

[0010] The first normally closed control valve, the flow regulating valve, and the second normally closed control valve are all electrically connected to the industrial computer; the gas storage tank is communicatively connected to the industrial computer via a 485 bus.

[0011] Furthermore, the gas grid group includes a plurality of evenly arranged groups of gas grids, each group of gas grids is connected to a corresponding branch pipeline, and is connected to a main calibration pipeline through the branch pipeline, each group of gas grids includes a plurality of evenly arranged gas grids, and the gas input port of each gas grid is connected to the branch pipeline through a sub-pipeline, a third normally closed control valve is provided on the sub-pipeline, and the third normally closed control valve is electrically connected to the industrial control machine.

[0012] Furthermore, it also includes an exhaust system, which is used to discharge the gas flowing through the gas detector to the outside. The gas grid is provided with a gas output port, and the gas output port is connected to an output pipeline. The various output pipelines are aggregated to a second aggregate pipeline, and the second aggregate pipeline is connected to the exhaust system. The exhaust system is electrically connected to the industrial control computer.

[0013] Furthermore, a charging calibration seat is provided inside the gas grid, and a charging port compatible with the gas detector is provided at the bottom of the charging calibration seat for charging the gas detector to be calibrated. The gas detector to be calibrated is located on the charging calibration seat; a gas inlet and a gas outlet are respectively provided on two side surfaces of the charging calibration seat, and the input gas entering the gas grid enters the gas detector through the gas inlet, and the gas passing through the gas detector is discharged through the gas outlet. The charging calibration seat is connected to the industrial computer via a 485 bus.

[0014] Furthermore, a solenoid valve is provided on the sub-pipeline corresponding to each of the gas grids, and the solenoid valve is controlled by a charging calibration socket.

[0015] Furthermore, it also includes:

[0016] A display device, used to be electrically connected to the industrial control machine, and the display device is used to display the current status information of the gas detector automatic calibration and the cabinet operation;

[0017] A face recognition device is arranged on the display device and is electrically connected to the industrial control machine. The face recognition device allows an operator to open or close the gas grid group based on recognition authority.

[0018] The present invention also discloses an automatic calibration method for a gas detection calibration cabinet, which uses the gas detection calibration cabinet to automatically calibrate a gas detector. The automatic calibration method includes:

[0019] Step 1: Place the gas detector to be calibrated in the gas grid, input the zeroing standard gas into the gas grid through the gas storage and delivery device, control the zeroing standard gas to zero the gas grid through the industrial computer, complete the zeroing adjustment of the gas detector to be calibrated, and obtain the zeroing calibration value;

[0020] Step 2, when the gas grid is in a state where the concentration of the gas to be calibrated is zeroed, the industrial computer controls the calibration standard gas corresponding to the type of gas to be calibrated to enter the gas grid according to the type of gas to be calibrated of the gas detector to be calibrated, completes the median adjustment of the gas detector to be calibrated, and obtains the median calibration value;

[0021] Step 3: The gas detector to be calibrated obtains the zero adjustment value and the median adjustment value, forms a calibration detection curve, and updates and stores it to complete automatic calibration.

[0022] Furthermore, in step 1, the gas detector to be calibrated is placed in the gas grid, and the gas grid is zeroed by controlling the zeroing standard gas through the industrial computer, including:

[0023] Step 101, control the door of the gas grid to be opened through the industrial computer, and place the gas detector to be calibrated on the charging calibration seat in the gas grid. After the gas detector to be calibrated is placed in the gas grid, close the door of the gas grid;

[0024] Step 102, the industrial computer (13) determines the zeroing standard gas according to the calibration requirements, and controls the first normally closed control valve and the second normally closed control valve of the gas storage tank included in the gas storage and delivery device corresponding to the zeroing standard gas to open;

[0025] Step 103, after the first normally closed control valve and the second normally closed control valve of the gas storage tank included in the gas storage and delivery device corresponding to the zeroing standard gas are opened, the industrial computer controls the flow regulating valve to adjust the gas flow, so as to gradually allow the zeroing standard gas to enter the main calibration pipeline, the branch pipeline and the sub-pipeline;

[0026] Step 104, after the main calibration pipeline, branch pipeline and sub-pipeline are filled with the zeroing standard gas, the third normally closed control valve corresponding to the gas grid containing the gas detector to be calibrated is opened by controlling the industrial computer, and the gas flow rate is adjusted to allow the zeroing standard gas to enter the gas grid, so that the gas concentration of the charging calibration seat in the gas grid reaches the zeroing state requirement.

[0027] Further, in step 2, when the gas grid is in a state where the concentration of the gas to be calibrated is zeroed, the industrial computer controls the calibration standard gas corresponding to the type of gas to be calibrated to enter the gas grid according to the type of gas to be calibrated of the gas detector to be calibrated, so that the gas detector to be calibrated completes automatic calibration, including:

[0028] Step 201: When the gas grid reaches a state where the concentration of the gas to be calibrated is zeroed and the state is maintained for a preset time, the industrial computer determines a calibration standard gas corresponding to the type of the gas to be calibrated of the gas detector to be calibrated according to the type of the gas to be calibrated of the gas detector to be calibrated;

[0029] Step 202, the industrial computer controls the first normally closed control valve and the second normally closed control valve of the gas storage tank included in the gas storage and delivery device corresponding to the calibration standard gas to open;

[0030] Step 203, after the normally closed control valve of the gas storage tank included in the gas storage and delivery device corresponding to the calibration standard gas is opened, the industrial computer adjusts the gas flow rate to gradually allow the calibration standard gas to enter the main calibration pipeline, the branch pipeline and the sub-pipeline;

[0031] Step 204, after the main calibration pipeline, branch pipelines and sub-pipelines are filled with the calibration standard gas, the third normally closed control valve corresponding to the gas grid containing the gas detector to be calibrated is opened by controlling the industrial computer, and the gas flow rate is adjusted to allow the calibration standard gas to enter the gas grid, so that the gas grid reaches the concentration calibration state of the gas to be calibrated, the median adjustment of the gas detector to be calibrated is completed, and the median calibration value is obtained.

[0032] Further, in step 3, the gas detector to be calibrated obtains a zero adjustment value and a median adjustment value, forms a calibration detection curve, and updates and stores it, including:

[0033] Step 301, setting the stabilization time according to the gas characteristic parameters of the calibration standard gas;

[0034] Step 302: after the gas detector to be calibrated obtains the median adjustment value, observe the median adjustment value of the gas detector to be calibrated according to a preset stabilization time to stabilize the median adjustment value obtained by the gas detector to be calibrated;

[0035] Step 303: extracting the median adjustment value and the zero adjustment value at the end of the stable time period;

[0036] Step 304: Form a calibration detection curve using the median adjustment value and the zero adjustment value, and update and store it.

[0037] Beneficial effects of the present invention:

[0038] The gas detection calibration cabinet and self-calibration method proposed in the present invention use the calibration cabinet. The calibration process is fully automatic and unattended, and the calibration is automatically performed in idle time without affecting production. The production efficiency of the enterprise is improved. At the same time, cloud services are supported, and the regulatory department can retrieve equipment information. It is helpful to supervise the production safety of the enterprise. At the same time, the flow and type of gas, as well as the flow of gas in the pipeline and gas grid are accurately controlled by the industrial computer, so that high-precision calibration of the gas detector to be calibrated can be achieved. The automated calibration process reduces the steps and time of manual operation and improves the calibration efficiency. Through the comprehensive control of the calibration process by the industrial computer, safety problems caused by human operating errors can be avoided. Regular automatic calibration can ensure the stability and accuracy of the gas detector and extend its service life.

[0039] On the other hand, this method can select the corresponding gas for calibration according to the type of gas to be calibrated of the gas detector to be calibrated, so it is suitable for the calibration of various gas types. At the same time, it can be easily integrated with existing gas detection systems and equipment, and can be expanded and customized as needed. In terms of performance indicators, the effect of this technology can be specifically reflected as follows: the calibrated gas detector has higher measurement accuracy and stability, and the error rate is significantly reduced; the degree of automation of the calibration process is improved, the calibration time is shortened, and the calibration efficiency is improved; at the same time, due to the reduction of manual operations, the safety and reliability of the calibration process have also been significantly improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Figure 1 This is a schematic diagram of the structure of the gas detection calibration cabinet of the present invention;

[0041] Figure 2 is a flow chart of the self-calibration method of the present invention;

[0042] Figure 3 This is a process diagram of the self-calibration method of the present invention.

[0043] 1. Gas storage tank; 2. Pressure reducing valve; 3. First normally closed control valve; 4. Flow regulating valve; 5. Second normally closed control valve; 6. Gas grid; 7. Third normally closed control valve; 8. First connecting pipeline; 9. Main calibration pipeline; 10. Branch pipeline; 11. Exhaust system; 12. Display device; 13. Industrial computer; 14. Face recognition device. DETAILED DESCRIPTION

[0044] The preferred embodiments of the present invention are described below in conjunction with the accompanying drawings. It should be understood that the preferred embodiments described herein are only used to illustrate and explain the present invention, and are not used to limit the present invention.

[0045] The embodiment of the present invention provides a gas detection calibration cabinet, such as Figure 1 As shown, the gas detection calibration cabinet includes multiple gas storage and delivery devices, an industrial computer 13 and multiple gas grid groups; wherein the control signal output end of the industrial computer 13 is connected to the control signal input end of the gas storage and delivery device; the gas outlet of the gas storage and delivery device is connected to the gas inlet of the gas grid group through the main calibration pipeline 9;

[0046] The industrial computer 13 is used to control the gas flow rate of the gas storage and delivery device, and to control the operation of the gas grid group;

[0047] A gas storage and delivery device, used to input the input gas into a corresponding column of gas grid groups according to the gas flow rate determined by the industrial computer 13;

[0048] The gas grid group is used to accommodate the gas detector to be calibrated, and automatically calibrate the gas detector by inputting zeroing standard gas and calibration standard gas respectively.

[0049] Among them, the gas storage and delivery device includes multiple gas storage tanks 1 corresponding to multiple gases; each gas storage tank 1 is used to store a single input gas. Two types of input gases are usually required in the calibration process of the gas detector, one is the zeroing gas, and the other is the calibration gas. The zeroing gas corresponds to the zeroing standard gas in the calibration method below, and the calibration gas corresponds to the calibration standard gas in the calibration method below. The zeroing gas usually includes compressed air and nitrogen. The calibration gas includes multiple types. The standard gas is set for different models of gas detectors. The gas detector supports calibration of multiple standard gases. Each standard gas is filled in the gas Inside the storage tank, usually, different gas detectors can usually detect one or more of the gases such as hydrogen sulfide, carbon monoxide, oxygen, sulfur dioxide, phosphine, ammonia, nitrogen dioxide, hydrogen cyanide, chlorine, chlorine dioxide, ozone and combustible gas. For example, if one of the gas detectors can detect oxygen, carbon monoxide and sulfur dioxide, then when calibrating the gas detector, the prepared oxygen, carbon monoxide and sulfur dioxide are respectively filled into different gas storage tanks as calibration gases. Usually, the zeroing gas is only nitrogen or compressed air, but the calibration gas is different, so it can be applied to the calibration process of different types of gas detectors. After calibrating one gas, you can recalibrate another gas, and so on, calibrating one by one.

[0050] The output sides of multiple gas storage tanks are aggregated to a first aggregate pipeline, and the output side of the first aggregate pipeline is connected to the main calibration pipeline 9 through a first connecting pipeline 8. A pressure reducing valve 2 and a first normally closed control valve 3 are provided between the output side of each gas storage tank 1 and the first aggregate pipeline. The pressure reducing valve 2 is usually provided as a manual pressure reducing valve, which can reduce the gas pressure of the input gas in the gas storage tank 1 to below 1Mpa to meet the need for gas circulation in the pipeline after output. The first normally closed control valve 3 is used to ensure that the gas storage tank remains in a normally closed state when not in operation, and to ensure the sealing and safety of the gas storage tank. The gas in the gas storage tank 1 can be output in the open state. This setting matches each gas storage tank 1 with a first normally closed control valve 3. When a part of the gas storage tank 1 is used, the gas in other gas storage tanks 1 that are not in use can still remain sealed without affecting the operation of other gas storage tanks 1.

[0051] The first connecting pipeline 8 is provided with a flow regulating valve 4 and a second normally closed control valve 5, and the first normally closed control valve 3, the flow regulating valve 4, and the second normally closed control valve 5 are all electrically connected to the industrial computer 13; the gas storage tank 1 is connected to the industrial computer 13 through a 485 bus for communication. The second normally closed control valve 5 is provided on the first connecting pipeline 8, which can ensure that each gas storage tank 1 is in a sealed state as a whole when not in operation. The flow regulating valve 4 controls the flow of the input gas, and the flow regulating valve 4 can adjust the gas flow output from the gas storage tank 1 under the control of the industrial computer 13. The flow regulating valve 4 can ensure that the required flow of zeroing gas and / or calibration gas is output during the gas calibration process, and the gas storage tank 1 is connected to the industrial computer 13 for communication through a 485 bus.

[0052] Among them, the gas grid group includes multiple groups of gas grids 6 arranged evenly, each group of gas grids 6 is connected to a corresponding branch pipeline 10, and is connected to the main calibration pipeline 9 through the branch pipeline 10. Each group of gas grids 6 includes multiple single gas grids 6 arranged evenly, which is equivalent to multiple single gas grids 6 being aggregated into one branch pipeline 10. Multiple branch pipelines 10 of multiple groups of gas grids 6 are then aggregated into the main calibration pipeline 9, and the gas input port of each gas grid 6 is connected to the branch pipeline 10 through a sub-pipeline. This layout method can ensure that the detection gas can be transmitted to each gas grid 6 at the same time through the main calibration pipeline 9. Multiple gas grids 6 in the gas grid group can automatically calibrate the gas detector at the same time, forming batch processing, improving work efficiency, and greatly reducing the workload of calibrating a single gas detector one by one. In addition, synchronous calibration can achieve unified calibration standards, and the calibration effect is stable and reliable. By connecting the branch pipeline to the main calibration pipeline 9, uniform diffusion between gases can be achieved, and the series connection ensures that the gas concentration in each gas grid 6 is the same, providing the same calibration environment.

[0053] At the same time, a charging calibration seat is arranged inside each gas grid 6, and a charging port compatible with the gas detector is arranged at the bottom of the charging calibration seat, which is used to charge the gas detector to be calibrated. The gas detector to be calibrated is located on the charging calibration seat, and a gas inlet and a gas outlet are respectively provided on both sides of the charging calibration seat. The input gas entering the gas grid 6 enters the gas detector through the gas inlet, and the gas passing through the gas detector is discharged through the gas outlet. During use, the gas detector to be calibrated is placed on the charging calibration seat to charge the gas detector to be calibrated, ensuring that the gas detector clock is in a powered state.

[0054] In addition, a third normally closed control valve 7 is provided on the sub-pipeline corresponding to each gas grid 6. The third normally closed control valve 7 can be selected as a solenoid valve. Each branch pipeline manages a row of equipment, and a row has M equipment. The calibration air intake path of each equipment is connected to the branch pipeline 10 through the third normally closed control valve 7. In addition, the third normally closed control valve 7 is controlled by a charging calibration seat. A solenoid valve control circuit is provided in the charging calibration seat for controlling the charging and communication management of the solenoid valve. The charging calibration seat is connected to the industrial computer 13 through an RS485 bus. After receiving the control signal of the industrial computer, the charging calibration seat can control the opening and closing of the third normally closed control valve 7 through the solenoid valve control circuit, thereby realizing the corresponding flow regulation of the gas flow on the sub-pipeline. The third normally closed control valve 7 can also be electrically connected to the industrial computer 13, and the opening and closing of the third normally closed control valve 7 can be controlled by the industrial computer 13. The third normally closed control valve 7 can ensure that the gas grid 6 is opened only when needed.

[0055] The calibration cabinet of the present invention also includes an exhaust system 11, which is used to discharge the gas flowing through the gas detector to the outside. A gas output port is provided on the gas grid 6, and the gas output port is connected to the output pipeline. Each output pipeline is aggregated to the second aggregate pipeline. The second aggregate pipeline is connected to the exhaust system 11. The exhaust system 11 is electrically connected to the industrial computer 13, and the exhaust system 11 is controlled by the industrial computer 13 to realize the exhaust cycle. That is, in the process of calibrating a specific gas detector, the zeroing gas is first selected, and the zeroing gas is transported to each gas grid by the gas storage and delivery device through the main calibration pipeline. The pipeline in the gas grid will introduce the gas into the gas detector to be calibrated, and the gas flowing through the detection equipment will be collected in the exhaust system through the second aggregate pipeline and discharged to the outside.

[0056] The external power supply of the cabinet is 220v single-phase electricity, and a power module is provided inside the cabinet to output the 24V electricity required by the equipment. All equipment (such as gas storage and delivery device) and gas are controlled by the industrial computer, which is linked to each device through the 485 bus to control the unlocking, calibration, charging and other states of the gas grid. At the same time, the cabinet of the present invention also includes a display device 12, which is electrically connected to the industrial computer 13. The display device 12 is used to display the current automatic calibration of the gas detector and the state information of the cabinet operation. Through the display device 12, it is convenient for the staff to intuitively understand the calibration process and calibration effect of the gas detector; and also includes a face recognition device 14, which is arranged on the display device 12 and electrically connected to the industrial computer 13. The face recognition device 14 is based on the recognition authority for the operator to open or close the gas grid group. Only under the premise of ensuring that the operator has the operation authority, can it be allowed to perform the calibration work, thereby improving the safety of the calibration cabinet, wherein the operation authority of each operator can be pre-set and face input can be performed, and the authority identification can be quickly passed through the face recognition method, and the degree of intelligence is high. The cabinet supports opening the electronic lock of the gas grid 6 through face recognition. The worker can automatically open the corresponding gas grid 6 after successful face recognition. After the gas grid 6 is opened, the worker can take out or put the gas detector into the charging and calibration base.

[0057] The gas detector in each gas grid 6 can be calibrated independently, and the gas detector in each gas grid 6 is a single or multi-in-one gas detector;

[0058] When performing gas calibration, before selecting a standard gas for calibration, for example, selecting nitrogen N2 as the zeroing gas, that is, the cleaning gas, first open the first normally closed control valve 3 on one side of the gas storage tank 1 filled with nitrogen N2 and the second normally closed control valve 5 on the first connecting pipeline, and adjust the flow rate through the flow regulating valve 4, clean the main calibration pipeline and the branch pipeline with dry nitrogen N2 gas, and empty the other gases originally stored in the calibration pipeline 9 and the branch pipeline 10; then close the first normally closed control valve 3 of nitrogen N2, open the first normally closed control valve 3 of the gas to be calibrated and the second normally closed control valve 5 on the first connecting pipeline, and adjust the flow rate through the flow regulating valve 4, and then from right to left, from top to bottom, open the third normally closed control valve 7 on the gas grid equipped with the gas detector to be detected in turn, and set the gas detector to the calibration mode of the corresponding gas, and calibrate each gas detector in turn; the entire calibration process and cabinet status are controlled by the industrial computer 13 of the calibration cabinet.

[0059] The effects of the above technical solutions are as follows: First, the fully automatic, unattended calibration process greatly reduces the burden of manual operations, reduces the risk of human error, and ensures the accuracy and consistency of calibration data. This instant and accurate calibration capability enables the gas detector to be calibrated to continue to maintain the best working condition, effectively avoiding false alarms or missed alarms due to equipment inaccuracy, and ensuring the safety and stability of the production environment. Secondly, by intelligently scheduling idle time for calibration, this technology maximizes the use of production gaps, achieves seamless integration of production and calibration, and does not require additional downtime, thereby significantly improving the company's production efficiency. This flexible calibration strategy not only reduces the waste of production costs, but also accelerates the product's time to market and enhances market competitiveness.

[0060] At the same time, through the precise control of the gas flow, type and gas flow in each pipeline and gas grid by the industrial computer 13, high-precision calibration of the gas detector to be calibrated is achieved. This precise control ensures the stability and consistency of the calibration process, thereby improving the accuracy of the calibration results. The automated calibration process significantly reduces the steps and time of manual operation, making the calibration process more efficient. At the same time, the rapid response and precise control of the industrial computer 13 also further shorten the calibration cycle and improve production efficiency. Through the comprehensive control of the calibration process by the industrial computer 13, safety problems caused by human operating errors are avoided. In addition, the automated calibration process also reduces the contact between personnel and harmful gases, ensuring the health and safety of the staff. Regular automatic calibration can ensure the stability and accuracy of the gas detector, timely discover and solve potential problems, thereby extending the service life of the gas detector. The system can flexibly select the corresponding gas for calibration according to the type of gas to be calibrated of the gas detector to be calibrated. This flexibility makes the method suitable for the calibration of multiple gas types, meeting the needs of different industries and application scenarios. The technical solution can be easily integrated with existing gas detection systems and equipment without making major changes to the existing system. At the same time, this technical solution also has good scalability and can be customized and expanded according to actual needs. In addition, due to the high degree of automation, the maintenance cost is relatively low. At the same time, the industrial computer can record the data of the entire calibration process, including gas flow, type, calibration time, etc., which provides convenience for subsequent data analysis and equipment maintenance. By analyzing the calibration data, the changing trend of equipment performance can be discovered in time, providing strong support for the preventive maintenance of the equipment.

[0061] In summary, this technical solution has shown significant technical effects in improving calibration accuracy, efficiency, safety, and equipment stability, and is highly flexible and easy to use, suitable for calibration needs of various gas types. The gas detection calibration cabinet and its self-calibration method not only improve the production efficiency and data accuracy of the enterprise, but also strengthen safety production management through intelligent and automated means, laying a solid foundation for the sustainable development of the enterprise.

[0062] The embodiment of the present invention provides an automatic calibration method for a gas detection calibration cabinet, see Figure 2 and Figure 3 , the automatic calibration method comprises:

[0063] Step 1: Place the gas detector to be calibrated in the gas grid 6, input the zeroing standard gas into the gas grid through the gas storage and delivery device, control the zeroing standard gas to zero the gas grid 6 through the industrial computer 13, complete the zeroing adjustment of the gas detector to be calibrated, and obtain the zeroing calibration value;

[0064] Step 2, when the gas grid 6 is in a state where the concentration of the gas to be calibrated is zeroed, the industrial computer controls the calibration standard gas corresponding to the type of gas to be calibrated to enter the gas grid through the industrial computer 13 according to the type of gas to be calibrated of the gas detector to be calibrated, completes the median adjustment of the gas detector to be calibrated, and obtains the median calibration value;

[0065] Step 3: The gas detector to be calibrated obtains the zero adjustment value and the median adjustment value, forms a calibration detection curve, and updates and stores it to complete automatic calibration.

[0066] The gas detector to be calibrated is placed in the gas grid 6, and the zeroing standard gas is controlled by the industrial computer 13 to perform zeroing control on the gas grid 6, including:

[0067] Step 101, control the cabinet door of the gas grid 6 to open through the industrial computer 13, and place the gas detector to be calibrated on the charging calibration seat in the gas grid 6. After the gas detector to be calibrated is placed in the gas grid 6, close the cabinet door of the gas grid 6;

[0068] Step 102: The industrial computer determines the zeroing standard gas according to the calibration requirements, and controls the first normally closed control valve and the second normally closed control valve of the gas storage tank included in the gas storage and delivery device corresponding to the zeroing standard gas to open;

[0069] Step 103, after the first normally closed control valve 3 and the second normally closed control valve 5 of the gas storage tank 1 included in the gas storage and delivery device corresponding to the zeroing standard gas are opened, the industrial computer 13 controls the flow regulating valve 4 to adjust the gas flow, so that the zeroing standard gas gradually enters the main calibration pipeline 9, the branch pipeline 10 and the sub-pipeline;

[0070] Step 104, when the main calibration pipeline 9, the branch pipeline 10 and the sub-pipeline are filled with the zeroing standard gas, the third normally closed control valve 7 corresponding to the gas grid 6 containing the gas detector to be calibrated is controlled by the industrial computer 13 to open, and the gas flow rate is adjusted to allow the zeroing standard gas to enter the gas grid 6, so that the gas concentration of the charging calibration seat in the gas grid 6 reaches the zeroing state requirement, and the zero point value is obtained.

[0071] Among them, when the gas grid 6 is in a state where the concentration of the gas to be calibrated is zeroed, the industrial computer 13 controls the calibration standard gas corresponding to the type of gas to be calibrated to enter the gas grid 6 according to the type of gas to be calibrated of the gas detector to be calibrated, so that the gas detector to be calibrated completes automatic calibration, including:

[0072] Step 201: When the gas grid 6 reaches a state where the concentration of the gas to be calibrated is zeroed and the state is maintained for a preset time, the industrial computer 13 determines a calibration standard gas corresponding to the type of the gas to be calibrated of the gas detector to be calibrated according to the type of the gas to be calibrated of the gas detector to be calibrated;

[0073] Step 202, the industrial computer 13 controls the first normally closed control valve 3 and the second normally closed control valve 5 of the gas storage tank 1 included in the gas storage and delivery device corresponding to the calibration standard gas to open;

[0074] Step 203, after the first normally closed control valve 3 and the second normally closed control valve 5 of the gas storage tank 1 included in the gas storage and delivery device corresponding to the calibration standard gas are opened, the industrial computer 13 adjusts the gas flow rate to gradually allow the calibration standard gas to enter the main calibration pipeline 9, the branch pipeline 10 and the sub-pipeline;

[0075] Step 204, when the main calibration pipeline 9, the branch pipeline 10 and the sub-pipeline are filled with the calibration standard gas, the third normally closed control valve 7 corresponding to the gas grid 6 containing the gas detector to be calibrated is controlled by the industrial computer 13 to open, and the gas flow is adjusted to allow the calibration standard gas to enter the gas grid 6, so that the gas grid 6 reaches the calibration state of the gas concentration to be calibrated, completes the median adjustment of the gas detector to be calibrated, and obtains the median calibration value. The calibration state of the gas concentration to be calibrated is usually the median concentration state of the gas detector, and the median value is obtained. The gas detector can draw a standard detection curve based on the zero point value and the median value, and the drawn standard detection curve is updated and stored as the standard value data of the calibrated gas detector.

[0076] The working principle of the above technical solution is as follows: the automatic calibration method mainly relies on the control of the industrial computer 13 over the gas storage and delivery device, as well as the flow of gas in each pipeline and the gas grid 6. First, the industrial computer 13 controls the zeroing standard gas to enter the gas grid 6, and the gas detector to be calibrated placed therein is zeroed and adjusted. The zeroing standard gas is used as zeroing gas for zero point calibration. Then, according to the type of gas to be calibrated of the gas detector to be calibrated, the industrial computer 13 controls the corresponding calibration standard gas to enter the gas grid 6. The calibration standard gas is used to calibrate the median value, which is the middle concentration of the range. After calibrating the median value, the gas detector to be calibrated completes the automatic calibration.

[0077] Specifically, the industrial computer 13 first controls the door of the gas grid 6 to open, places the gas detector to be calibrated in the gas grid 6, and closes the door. Then, the industrial computer 13 determines the zeroing standard gas according to the calibration requirements, and controls the first normally closed control valve 3 and the second normally closed control valve 5 of the gas storage tank 1 of the corresponding gas storage and delivery device to open. Next, the industrial computer 13 adjusts the gas flow rate so that the zeroing standard gas gradually enters the main calibration pipeline 9, the branch pipeline 10 and the sub-pipeline, and finally enters the gas grid 6, so that the gas concentration of the charging calibration seat in the gas grid 6 reaches the zeroing state requirement.

[0078] After the gas grid 6 reaches the state where the concentration of the gas to be calibrated is zero, the industrial computer 13 maintains this state for a preset length of time. Then, according to the type of gas to be calibrated of the gas detector to be calibrated, the industrial computer 13 determines the corresponding calibration standard gas, and controls the first normally closed control valve 3 and the second normally closed control valve 5 of the gas storage tank 1 of the corresponding gas storage and delivery device to open. Then, the industrial computer 13 adjusts the gas flow rate again, so that the calibration standard gas gradually enters the main calibration pipeline 9, the branch pipeline 10 and the sub-pipeline, and finally enters the gas grid 6, so that the gas grid 6 reaches the calibration state of the gas concentration to be calibrated, and the gas detector to be calibrated completes the automatic calibration.

[0079] The effect of the above technical solution is: by accurately controlling the flow rate and type of gas, as well as the flow of gas in the pipeline and gas grid through the industrial computer 13, high-precision calibration of the gas detector to be calibrated can be achieved. The automated calibration process reduces the steps and time of manual operation and improves the calibration efficiency. Through the comprehensive control of the calibration process by the industrial computer 13, safety problems caused by human operation errors can be avoided. Regular automatic calibration can ensure the stability and accuracy of the gas detector and extend its service life. The method can select the corresponding gas for calibration according to the type of gas to be calibrated of the gas detector to be calibrated, so it is suitable for the calibration of multiple gas types. At the same time, it can be easily integrated with existing gas detection systems and equipment, and can be expanded and customized as needed. In terms of performance indicators, the technical effect can be specifically reflected as follows: the calibrated gas detector has higher measurement accuracy and stability, and the error rate is significantly reduced; the degree of automation of the calibration process is improved, the calibration time is shortened, and the calibration efficiency is improved; at the same time, due to the reduction of manual operation, the safety and reliability of the calibration process are also significantly improved.

[0080] In one embodiment of the present invention, after the normally closed control valve of the gas storage tank included in the gas storage and delivery device corresponding to the zeroing standard gas is opened, the detailed steps of the industrial computer 13 for regulating the gas flow are as follows:

[0081] Determine input gas and its corresponding gas delivery module, wherein the gas delivery module includes a plurality of gas storage tanks 1;

[0082] Open the first normally closed control valve 3 and the second normally closed control valve 5 provided on the gas supply module to transmit the input gas to the gas grid 6;

[0083] When the input gas is compressed and transmitted to the gas grid 6, the flow rate of the input gas is adjusted by controlling the first normally closed control valve 3 and the second normally closed control valve 5 so that the flow rate of the input gas reaches a preset first standard flow rate value; wherein the first standard flow rate value is obtained by the following formula:

[0084]

[0085] Among them, G 01 Indicates the first standard flow rate value; G c Indicates the preset initial standard flow rate value; V z Represents the overall volume of the gas grid; V y represents the gas volume corresponding to the remaining gas of the last input gas calibration; g represents the adjustment coefficient; and the adjustment coefficient is obtained by the following formula:

[0086]

[0087] Among them, V d It indicates the volume of gas compressed into the gas grid per unit time of operation, and the unit time is 15s-60s; when season

[0088] Controlling the input gas according to the first standard flow rate value to replace all the remaining gas from the last input gas calibration in the gas grid 6;

[0089] After all the remaining gas in the gas grid 6 is replaced, the input gas concentration is controlled to return to zero.

[0090] The working principle of the above technical solution is as follows: first, determine the required first or second input gas according to the calibration requirements, and select the corresponding gas delivery module. Open the first normally closed control valve 3 and the second normally closed control valve 5 on the gas delivery module to compress the input gas and deliver it to the gas grid.

[0091] The first standard flow rate value (G01) is calculated according to a preset formula, which takes into account the initial standard flow rate value (Gc), the overall volume of the gas grid (Vz), the remaining gas volume from the last calibration (Vy) and the adjustment coefficient (g). The adjustment coefficient (g) is calculated based on the volume of gas (Vd) compressed into the gas grid 6 by the air compressor per unit time, and the unit time can be set to 15 seconds to 60 seconds. The flow rate of the input gas is controlled according to the calculated first standard flow rate value to ensure that the remaining gas from the last calibration remaining in the gas grid is completely replaced by the newly input gas. This process achieves efficient gas replacement by precisely controlling the flow rate. After all the remaining gas in the gas grid 6 has been replaced, the gas concentration in the gas grid is brought to a zero state by further controlling the flow rate of the input gas, in preparation for subsequent calibration operations.

[0092] The technical effect of the above technical solution is: by accurately controlling the flow rate and concentration of the input gas, the accuracy and consistency of the gas composition in the gas grid 6 are ensured, thereby improving the accuracy of subsequent calibration operations. The automated flow rate adjustment and gas replacement process reduces human intervention, reduces operating errors, and enhances the stability and reliability of the entire calibration system. Through fast and accurate gas replacement and concentration zeroing operations, the calibration cycle is shortened and work efficiency is improved. The technical solution can flexibly adjust the flow rate and concentration parameters according to the characteristics and calibration requirements of different gases, and has strong adaptability and flexibility. By recording the key parameters and data in the flow rate adjustment and gas replacement process, it provides strong support for subsequent data analysis and troubleshooting, and enhances the traceability of the data. At the same time, the gas injection flow value will affect the time it takes for the gas to reach uniform distribution in the gas grid, which will lead to differences in the gas concentration received by the gas-sensitive component at different locations or times. At the same time, since the response of the gas-sensitive component to the gas usually has a certain lag time, the inappropriate gas injection flow will cause the accumulation and release of gas on the surface of the component, which may lead to a prolonged response time. Therefore, obtaining the flow rate in the above manner can ensure that the speed of uniform distribution of gas in the gas grid is optimal. The above technical solution can effectively improve the rationality of flow control, so that the gas will enter the gas-sensitive component with a more uniform concentration and speed coordination, thereby improving the response accuracy and stability of the gas-sensitive component and reducing the error caused by uneven gas concentration. Gas-sensitive components have a certain response time when detecting gas. Therefore, by controlling the flow rate of the gas, the residence time of the gas on the surface of the component can be reduced, and its dynamic response speed can be improved, ensuring that the gas-sensitive component can quickly and accurately feedback the current gas concentration during the calibration process. At the same time, flow rate regulation can optimize the sensitivity of gas-sensitive components, so that they can better adapt to gases of different concentration levels during calibration, thereby improving the resolution of calibration. Different types of gases may have different physical and chemical properties (such as density, viscosity, etc.), and the control of the flow rate can be optimized according to the characteristics of the gas to ensure that the best calibration effect can be achieved during the calibration process.

[0093] In summary, this technical solution achieves efficient and accurate gas replacement and concentration zeroing operations by precisely controlling the flow rate and concentration of the input gas, laying a solid foundation for subsequent calibration work.

[0094] In one embodiment of the present invention, after the solenoid valve of the gas storage tank included in the gas storage and delivery device corresponding to the calibration standard gas is opened, the detailed steps of the industrial computer for regulating the gas flow are as follows:

[0095] When the first normally closed control valve 3 and the second normally closed control valve 5 of the gas storage tank 1 included in the gas storage and delivery device corresponding to the calibration standard gas are opened, the flow rate of the input gas is adjusted by controlling the first normally closed control valve 3 and the second normally closed control valve 5, so that the flow rate of the input gas reaches a preset second standard flow rate value; wherein the second standard flow rate value is obtained by the following formula:

[0096]

[0097] Among them, G 02 Indicates the second standard flow rate value; G 01 Indicates the first standard flow rate value; G c represents the preset initial standard flow rate value; g represents the adjustment coefficient;

[0098] After the flow rate of the input gas reaches a preset second standard flow rate value, the concentration of the input gas is controlled to reach a preset calibration target concentration.

[0099] The working principle of the above technical solution is: when the first normally closed control valve 3 and the second normally closed control valve 5 of the gas storage and delivery device corresponding to the calibration standard gas receive an opening signal, the valve opens to allow the gas to flow. The industrial computer 13 calculates the second standard flow rate value (G02) according to a preset formula, which is based on the first standard flow rate value (G01), the preset initial standard flow rate value (Gc) and the adjustment coefficient (g). Then, the industrial computer 13 adjusts the flow rate of the input gas by controlling the first normally closed control valve 3 and the second normally closed control valve 5 to reach this second standard flow rate value. After the flow rate of the input gas reaches the preset second standard flow rate value, the industrial computer 13 further controls the concentration of the input gas to reach the preset calibration target concentration.

[0100] The technical effect of the above technical solution is: the accuracy and stability of the gas calibration process are ensured by the precise control of the flow rate and concentration of the input gas by the industrial computer 13. Automated flow rate and concentration control reduces manual intervention, shortens the calibration cycle, and improves work efficiency. The technical solution can flexibly adjust the flow rate and concentration parameters according to the characteristics of different gases and calibration requirements, and has strong adaptability and flexibility. By precisely controlling the flow rate and concentration of the input gas, the calibration process is more reliable and the quality of the calibration results is improved. The industrial computer 13 records the key parameters and data in the flow rate and concentration control process, providing strong support for subsequent data analysis and troubleshooting. At the same time, the gas injection flow value will affect the time it takes for the gas to reach uniform distribution in the gas grid, which will lead to differences in the gas concentration received by the gas-sensitive components at different positions or times. At the same time, since the response of the gas-sensitive components to the gas usually has a certain lag time, the incompatible gas injection flow will cause the accumulation and release of the gas on the surface of the component, which may lead to a prolonged response time. Therefore, obtaining the flow rate in the above manner can ensure that the speed of uniform distribution of the gas in the gas grid 6 is optimal. The above technical solution can effectively improve the rationality of flow control, so that the gas will enter the gas-sensitive components with a more uniform concentration and speed, thereby improving the response accuracy and stability of the gas-sensitive components and reducing the error caused by uneven gas concentration. Gas-sensitive components have a certain response time when detecting gas. Therefore, by controlling the flow rate of the gas, the residence time of the gas on the surface of the component can be reduced, and its dynamic response speed can be improved, ensuring that the gas-sensitive components can quickly and accurately feedback the current gas concentration during the calibration process. At the same time, flow rate regulation can optimize the sensitivity of gas-sensitive components, so that they can better adapt to gases of different concentration levels during calibration, thereby improving the resolution of calibration. Different types of gases may have different physical and chemical properties (such as density, viscosity, etc.), and the control of the flow rate can be optimized according to the characteristics of the gas to ensure that the best calibration effect can be achieved during the calibration process.

[0101] In summary, this technical solution realizes an efficient and accurate gas calibration process through the precise control of the flow rate and concentration of the input gas by the industrial computer, improves the calibration efficiency and quality, and enhances the adaptability and flexibility of the system.

[0102] In one embodiment of the present invention, in step 3, the gas detector to be calibrated obtains a zero adjustment value and a median adjustment value, forms a calibration detection curve, and updates and stores it, including:

[0103] Step 301, setting the stabilization time according to the gas characteristic parameters of the calibration standard gas;

[0104] Step 302: after the gas detector to be calibrated obtains the median adjustment value, observe the median adjustment value of the gas detector to be calibrated according to a preset stabilization time to stabilize the median adjustment value obtained by the gas detector to be calibrated;

[0105] Step 303: extracting the median adjustment value and the zero adjustment value at the end of the stable time period;

[0106] Step 304: Form a calibration detection curve using the median adjustment value and the zero adjustment value, and update and store it.

[0107] Among them, according to the gas characteristic parameters of the calibration standard gas, the stabilization time is set, including:

[0108] Step 3011: extract the gas characteristic parameters of the calibration standard gas, wherein the gas characteristic parameters include gas density, gas flow rate value (i.e., the second standard flow rate value G 02 ) and gas pressure;

[0109] Step 3012: Using the gas density and gas flow rate value (i.e., the second standard flow rate value G 02 ) and gas pressure to obtain stable time setting coefficient;

[0110] The stable duration setting coefficient is obtained by the following formula:

[0111]

[0112] Among them, λ represents the stable time setting coefficient; ρ represents the gas density; ρ c Indicates the preset gas density reference value; P s Indicates the preset pressure reference value; P indicates gas pressure; G 02 Indicates the second standard flow rate value; G c Indicates the preset initial standard flow rate value;

[0113] Step 3013: retrieve the initial stable duration, and use the initial stable duration combined with the stable duration setting coefficient to obtain the stable duration, wherein the stable duration is obtained by the following formula:

[0114]

[0115] Where, T represents the stable duration; T g represents the initial stable time; λ represents the stable time setting coefficient.

[0116] The working principle of the above technical solution is: extract the gas characteristic parameters of the calibration standard gas, including gas density (ρ), gas flow rate value (G 02) and gas pressure (P). The stabilization time setting coefficient (λ) is calculated using a specific formula using the gas density, gas flow rate value and gas pressure. The above technical solution takes into account the difference between the gas density and the preset density reference value, the difference between the gas pressure and the preset pressure reference value, and the difference between the gas flow rate value and the preset initial standard flow rate value. The initial stabilization time (Tg) is retrieved, and the final stabilization time (T) is adjusted according to the stabilization time setting coefficient (λ). After the gas detector to be calibrated obtains the median adjustment value, it is observed according to the calculated stabilization time to ensure the stability of the median adjustment value. At the end of the stabilization time, the median adjustment value and the zero adjustment value are extracted. These two values ​​are used to form a calibration detection curve, which is updated and stored.

[0117] The technical effect of the above technical solution is: the above technical solution calculates the stabilization time setting coefficient by introducing gas characteristic parameters (such as gas density, gas flow rate value and gas pressure), and then determines the specific stabilization time. This customized stabilization time setting method can ensure the best stability when observing the median adjustment value according to the characteristics of different gases, thereby significantly improving the accuracy of calibration. After the stabilization time is over, the technical solution requires accurate extraction of the median adjustment value and the zero adjustment value. This step ensures the accuracy of the calibration data and provides a reliable basis for the subsequent formation of the calibration detection curve. Calibration curve optimization: Using the accurately extracted median adjustment value and the zero adjustment value, the technical solution can form a more accurate calibration detection curve. This curve reflects the response characteristics of the gas detector under different gas conditions and provides an accurate reference for subsequent gas detection. At the same time, the calibration process in the above technical solution includes multiple steps such as value extraction, calculation, observation and curve formation, which can be automated to reduce manual intervention. This not only improves the calibration efficiency, but also reduces the risk of human error.

[0118] At the same time, setting the stabilization time allows the gas detector to be calibrated to have enough time to observe after obtaining the median adjustment value to ensure that the value reaches a stable state. Stable values ​​can more accurately reflect the performance of the gas detector, thereby improving the accuracy of calibration. During the stabilization time, the gas detector has enough time to adapt to the current gas environment and reduce errors caused by environmental changes or unstable initial state of the instrument. This helps to form a more accurate calibration detection curve and provide a more reliable reference for subsequent gas detection. At the same time, setting the stabilization time is an important part of the calibration process, which ensures the orderly progress of the calibration process. By reasonably arranging the stabilization time, the entire calibration process can be optimized, unnecessary waiting time can be reduced, and calibration efficiency can be improved. Stable values ​​mean that the gas detector can meet the calibration requirements in a short time without repeated calibration. This helps to shorten the calibration cycle and enable the gas detector to be put into practical use faster. By calculating the stabilization time based on the gas characteristic parameters of the calibration standard gas (such as gas density, gas flow rate value, and gas pressure), the technical solution can adapt to the characteristics of different gases. This enables the gas detector to maintain high accuracy and stability in a variety of gas environments and enhances its adaptability. Stable values ​​and calibration processes help ensure that the gas detector maintains high accuracy and stability during long-term use. This helps to extend the service life of the instrument, reduce the failure rate, and improve the reliability of the instrument. At the same time, by reasonably setting the stabilization time, it is possible to avoid waste of resources due to insufficient or excessive observation time. This helps to save manpower, material and time costs and improve resource utilization efficiency. A stable calibration process can ensure the stability and consistency of the calibration quality. This helps to reduce the cost of repeated calibration and maintenance caused by poor calibration quality and improve overall economic benefits.

[0119] In summary, by setting the stabilization time, this technical solution has achieved significant technical effects in terms of performance indicators. It not only improves calibration accuracy and efficiency, but also enhances adaptability and reliability, and optimizes resource utilization. These technical effects together constitute the powerful advantage of this technical solution in improving the performance of gas detectors.

[0120] In one embodiment of the present invention, the control operation of the industrial computer 13 also includes that the face recognition device 14 allows the operator to open or close the gas grid group based on the recognition authority, and the calibration operation process of the gas detector to be calibrated of the gas grid 6 is monitored and controlled by the staff, including:

[0121] Control the face recognition device 14 to collect facial images of staff members in real time;

[0122] Comparing the staff member's facial image with the staff member's input facial image stored in the database for similarity;

[0123] Whether to control the cabinet to open the gas grid 6 is determined according to the similarity comparison result between the staff face image and the staff input face image stored in the database.

[0124] The working principle of the above technical solution is: through the face recognition device 14 installed in the calibration cabinet or the surrounding area, the facial image of the staff in the current working area is captured and collected in real time. This step is performed automatically without manual intervention. The collected facial image of the staff is compared with the facial image of the staff pre-stored in the database, and the similarity between the two is calculated using the face recognition algorithm. The purpose of this step is to verify whether the identity of the current staff matches the authorized person in the database. Based on the result of the similarity comparison, the system determines whether the current staff is an authorized person. If the similarity reaches the preset threshold (that is, it is determined to be the same person), the system considers that the identity authentication is passed, and controls a gas grid (or door, drawer, etc.) of the cabinet (which may be a gas detection calibration cabinet or other equipment that requires safety control) to open, allowing the staff to proceed to the next step. If the similarity does not reach the threshold, the identity authentication fails, the cabinet remains closed, and unauthorized access is prevented.

[0125] The effect of the above technical solution is: by introducing face recognition technology, real-time verification of the identity of the staff is realized, which effectively prevents unauthorized personnel from illegally accessing the calibration cabinet or other sensitive equipment, and significantly enhances the security of the equipment during use. For authorized staff, this automated identity authentication process does not require carrying additional keys, access cards and other items, and identity authentication can be completed through facial recognition, which greatly improves the convenience of operation. The system can automatically record each access attempt and its results, providing detailed data support for the company's security management. Managers can conduct statistical analysis based on this, optimize security management strategies, and improve overall management efficiency. Compared with traditional identity authentication methods (such as passwords, keys, etc.), face recognition technology has higher accuracy and reliability, and can significantly reduce erroneous authentication caused by human negligence or intentional. Combined with cloud services and remote monitoring technology, the company's management or regulatory department can view the use and access records of the cabinet in real time, and realize remote monitoring and management of production safety and production efficiency.

[0126] Specifically, determining whether to control the cabinet to open the gas grid 6 according to the similarity comparison result between the facial image of the staff member and the facial image of the staff member entered and stored in the database includes:

[0127] When the image similarity between the staff member's facial image and the staff member's recorded facial image stored in the database reaches a preset similarity threshold, the cabinet is controlled to open the gas grid 6;

[0128] When the image similarity between the staff member's facial image and the staff member's input facial image stored in the database does not reach a preset similarity threshold, extracting a contrast value of the staff member's facial image as a first contrast value;

[0129] Extracting a contrast value of the facial image entered by the staff member as a second contrast value;

[0130] The target contrast value corresponding to the staff facial image is obtained by using the first contrast value, the second contrast value and the image similarity between the staff facial image and the staff input facial image stored in the database; wherein the target contrast value is obtained by the following formula:

[0131]

[0132] Among them, S m represents the target contrast value corresponding to the staff member's facial image; S 01 Represents the first contrast value; S 02 represents the second contrast value; ΔS represents the contrast compensation amount, and the contrast compensation amount is obtained by the following formula:

[0133]

[0134] Where, ΔS represents the contrast compensation amount; D y Indicates the preset similarity threshold; D 01 Indicates the image similarity between the staff member's facial image and the staff member's input facial image stored in the database;

[0135] Adjusting the contrast value of the staff member's facial image according to the target contrast value to obtain the staff member's facial image after contrast adjustment;

[0136] Comparing the contrast-adjusted facial image of the staff member with the facial image of the staff member entered and stored in the database for similarity;

[0137] When the image similarity between the contrast-adjusted staff facial image and the staff recorded facial image stored in the database reaches a preset similarity threshold, the cabinet is controlled to open the gas grid 6; otherwise, the control body prohibits opening the gas grid 6.

[0138] The working principle of the above technical solution is as follows: First, the system compares the similarity between the real-time collected facial image of the staff and the recorded facial image stored in the database. If the similarity reaches the preset similarity threshold, the cabinet is directly controlled to open the gas grid to allow access. If the preliminary similarity comparison does not reach the threshold, the system will further analyze the cause and try to improve the recognition effect by adjusting the contrast. At this time, the contrast values ​​of the real-time facial image (first contrast value) and the recorded facial image (second contrast value) are extracted respectively. Based on the first contrast value, the second contrast value and the preliminary similarity result, the target contrast value is calculated by a specific formula. This formula takes into account the contrast compensation amount (ΔS), which is dynamically adjusted according to the gap between the preliminary similarity and the threshold, aiming to improve the accuracy of subsequent similarity comparisons by optimizing the contrast. According to the calculated target contrast value, the contrast of the real-time collected facial image of the staff is adjusted to generate a contrast-adjusted facial image. The contrast-adjusted facial image is compared again with the recorded facial image stored in the database for similarity. According to the result of the second similarity comparison, if the similarity reaches a preset similarity threshold, the control cabinet opens the gas grid; if it still does not reach the threshold, the control cabinet prohibits opening the gas grid and prevents access.

[0139] The effect of the above technical solution is: by introducing a contrast adjustment mechanism, the technical solution can overcome the influence of factors such as lighting changes and facial shadows on the accuracy of face recognition to a certain extent, and improve the recognition effect in different environments. The contrast adjustment is dynamically performed based on the similarity difference between the real-time facial image and the recorded image, so the technical solution can better adapt to the changes in facial features of different individuals and improve the flexibility and adaptability of the system. For users, even in poor lighting or changes in facial features, a higher recognition accuracy can be obtained through the system's automatic contrast adjustment mechanism, thereby reducing the inconvenience and trouble caused by recognition failure. Although the contrast adjustment step is added, the overall process still strictly follows the identity authentication principle based on facial image similarity, ensuring that only authorized personnel can access the cabinet, thereby maintaining the security of the equipment and the confidentiality of the data.

[0140] Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include these modifications and variations.

Claims

1. A gas detection calibration cabinet, characterized in that: The invention comprises a plurality of gas storage and delivery devices, an industrial computer (13) and a plurality of gas grid groups; wherein the control signal output end of the industrial computer (13) is connected to the control signal input end of the gas storage and delivery device; and the gas outlet of the gas storage and delivery device is connected to the gas inlet of the gas grid group through a main calibration pipeline; The industrial computer (13) is used to control the gas flow rate of the gas storage and delivery device, and to control the operation of the gas grid group; The gas storage and delivery device is used to input the input gas into a corresponding column of gas grid groups according to the gas flow rate determined by the industrial control computer (13); The gas grid group is used to accommodate the gas detector to be calibrated, and automatically calibrate the gas detector by respectively inputting the zeroing standard gas and the calibration standard gas.

2. The gas detection calibration cabinet according to claim 1, characterized in that: The gas storage and delivery device comprises a plurality of gas storage tanks (1) corresponding to a plurality of input gases; each of the gas storage tanks (1) is used to store a single input gas, wherein the input gas comprises a zeroing gas and a calibration gas; wherein the output sides of the plurality of gas storage tanks (1) are aggregated to a first aggregate pipeline, the output side of the first aggregate pipeline is connected to the main calibration pipeline (9) via a first connecting pipeline (8), and a pressure reducing valve (2) and a first normally closed control valve (3) are provided between the output side of each gas storage tank (1) and the first aggregate pipeline; The first communicating pipeline is provided with a flow regulating valve (4) and a second normally closed control valve (5) in turn; The first normally closed control valve (3), the flow regulating valve (4), and the second normally closed control valve (5) are all electrically connected to the industrial computer; and the gas storage tank is communicatively connected to the industrial computer via a 485 bus.

3. The gas detection calibration cabinet according to claim 1, characterized in that: The gas grid group comprises a plurality of evenly arranged groups of gas grids (6), each group of gas grids (6) is connected to a corresponding branch pipeline (10) and is connected to a main calibration pipeline (9) via the branch pipeline (10), each group of gas grids comprises a plurality of evenly arranged gas grids (6), a gas input port of each gas grid (6) is connected to the branch pipeline via a sub-pipeline, a third normally closed control valve (7) is provided on the sub-pipeline, and the third normally closed control valve (7) is electrically connected to the industrial computer (13).

4. The gas detection calibration cabinet according to claim 3, characterized in that: It also includes an exhaust system, which is used to discharge the gas flowing through the gas detector to the outside. The gas grid (6) is provided with a gas output port, and the gas output port is connected to an output pipeline. The various output pipelines are aggregated into a second aggregate pipeline, and the second aggregate pipeline is connected to the exhaust system (11). The exhaust system (11) is electrically connected to the industrial computer (13).

5. The gas detection calibration cabinet according to claim 3, characterized in that: A charging calibration seat is arranged inside the gas grid (6), and a charging port adapted to the gas detector is arranged at the bottom of the charging calibration seat for charging the gas detector to be calibrated, and the gas detector to be calibrated is seated on the charging calibration seat; a gas inlet and a gas outlet are respectively arranged on two side surfaces of the charging calibration seat, and the input gas entering the gas grid (6) enters the gas detector through the gas inlet, and the gas passing through the gas detector is discharged through the gas outlet, wherein the charging calibration seat is connected to the industrial computer (13) via a 485 bus.

6. The gas detection calibration cabinet according to claim 1, characterized in that: Also includes: A display device (12) is used to be electrically connected to the industrial computer (13), and the display device (12) is used to display current status information of automatic calibration of the gas detector and operation of the cabinet; A face recognition device (14) is arranged on the display device (12) and is electrically connected to the industrial computer (13). The face recognition device (14) allows an operator to open or close the gas grid group based on recognition authority.

7. An automatic calibration method for a gas detection calibration cabinet, using the gas detection calibration cabinet described in any one of claims 1 to 6 to automatically calibrate a gas detector, characterized in that: The automatic calibration method comprises: Step 1: Place the gas detector to be calibrated in the gas grid (6), input zeroing standard gas into the gas grid through the gas storage and delivery device, control the zeroing standard gas to zero the gas grid (6) through the industrial computer (13), complete the zeroing adjustment of the gas detector to be calibrated, and obtain the zeroing calibration value; Step 2, when the gas grid (6) is in a state where the concentration of the gas to be calibrated is zeroed, the industrial computer controls the calibration standard gas corresponding to the type of gas to be calibrated to enter the gas grid through the industrial computer (13) according to the type of gas to be calibrated of the gas detector to be calibrated, completes the median adjustment of the gas detector to be calibrated, and obtains the median calibration value; Step 3: The gas detector to be calibrated obtains the zero adjustment value and the median adjustment value, forms a calibration detection curve, and updates and stores it to complete automatic calibration.

8. The automatic calibration method according to claim 7, characterized in that: In step 1, a gas detector to be calibrated is placed in a gas grid (6), and a zeroing standard gas is controlled by an industrial computer (13) to perform zeroing control on the gas grid (6), including: Step 101, controlling the cabinet door of the gas grid (6) to open by means of the industrial computer (13), and placing the gas detector to be calibrated on the charging calibration seat in the gas grid (6), and after the gas detector to be calibrated is placed in the gas grid (6), closing the cabinet door of the gas grid (6); Step 102, the industrial computer (13) determines the zeroing standard gas according to the calibration requirements, and controls the first normally closed control valve (3) and the second normally closed control valve (5) of the gas storage tank (1) included in the gas storage and delivery device corresponding to the zeroing standard gas to open; Step 103: After the first normally closed control valve (3) and the second normally closed control valve (5) of the gas storage tank (1) included in the gas storage and delivery device corresponding to the zeroing standard gas are opened, the industrial computer (13) controls the flow regulating valve (4) to adjust the gas flow rate, so that the zeroing standard gas gradually enters the main calibration pipeline (9), the branch pipeline (10) and the sub-pipeline; Step 104: After the main calibration pipeline (9), the branch pipeline (10) and the sub-pipeline are filled with the zeroing standard gas, the industrial computer (13) controls the third normally closed control valve (7) corresponding to the gas grid (6) containing the gas detector to be calibrated to open, and adjusts the gas flow rate so that the zeroing standard gas enters the gas grid (6) and the gas concentration of the charging calibration seat in the gas grid (6) reaches the zeroing state requirement.

9. The automatic calibration method according to claim 8, characterized in that: In step 2, when the gas grid (6) is in a state where the concentration of the gas to be calibrated is zeroed, the industrial computer (13) controls the calibration standard gas corresponding to the type of the gas to be calibrated to enter the gas grid (6) according to the type of the gas to be calibrated of the gas detector to be calibrated, thereby completing the median adjustment of the gas detector to be calibrated, including: Step 201, when the gas grid (6) reaches a state where the concentration of the gas to be calibrated is zeroed, and the state where the concentration of the gas to be calibrated is zeroed is maintained for a preset time length, the industrial computer (13) determines, according to the type of the gas to be calibrated of the gas detector to be calibrated, a calibration standard gas corresponding to the type of the gas to be calibrated of the gas detector to be calibrated; Step 202: the industrial computer (13) controls the first normally closed control valve (3) and the second normally closed control valve (5) of the gas storage tank (1) included in the gas storage and delivery device corresponding to the calibration standard gas to open; Step 203: after the first normally closed control valve (3) and the second normally closed control valve (5) of the gas storage tank (1) included in the gas storage and delivery device corresponding to the calibration standard gas are opened, the calibration standard gas is input into the gas grid (6) through the gas storage and delivery device, and the industrial computer (13) adjusts the gas flow rate to gradually allow the calibration standard gas to enter the main calibration pipeline (9), the branch pipeline (10) and the sub-pipeline; Step 204: After the main calibration pipeline (9), the branch pipeline (10) and the sub-pipeline are filled with the calibration standard gas, the industrial computer (13) controls the third normally closed control valve (7) corresponding to the gas grid (6) containing the gas detector to be calibrated to open, and adjusts the gas flow rate so that the calibration standard gas enters the gas grid (6), so that the gas grid (6) reaches the concentration calibration state of the gas to be calibrated, completes the median adjustment of the gas detector to be calibrated, and obtains the median calibration value.

10. The automatic calibration method according to claim 8, characterized in that: In step 3, the gas detector to be calibrated obtains the zero adjustment value and the median adjustment value, forms a calibration detection curve, and updates and stores it, including: Step 301, setting the stabilization time according to the gas characteristic parameters of the calibration standard gas; Step 302: after the gas detector to be calibrated obtains the median adjustment value, observe the median adjustment value of the gas detector to be calibrated according to a preset stabilization time to stabilize the median adjustment value obtained by the gas detector to be calibrated; Step 303: extracting the median adjustment value and the zero adjustment value at the end of the stable time period; Step 304: Form a calibration detection curve using the median adjustment value and the zero adjustment value, and update and store it.

Images