A gas monitoring control system and method based on a solid oxygen respirator

Abstract

The present application belongs to the technical field of respirator parameter monitoring, in particular to a gas monitoring control system and method based on a solid oxygen respirator, which solves the technical problems of the existing respiratory protection equipment in the aspects of parameter control and monitoring, inability to accurately predict the remaining protection time, and lack of working data storage function. The gas monitoring control system includes a gas parameter monitoring module corresponding to the monitoring point in the gas circuit of the solid oxygen respirator, a central processing and control unit, an electric ignition execution module for controlling each electric igniter to perform ignition start-stop actions, a human-computer interaction terminal, and a power management module. The gas monitoring control method combines gas concentration, gas flow, and multi-dimensional joint criterion control algorithm of running time to control the solid oxygen source module in sequence, aiming to balance oxygen supply and timeliness and system stability, avoid unnecessary ignition oxygen loss, and ensure reliable ignition oxygen supply in the case of oxygen deficiency and time conditions.

Description

Technical Field

[0001] This invention relates to the field of respirator parameter monitoring technology, and in particular to a gas monitoring and control system and method based on a solid oxygen respirator. Background Technology

[0002] Respiratory protection equipment in the emergency rescue field is divided into two main categories based on the type of gas source: air respirators (BRIs) and oxygen respirators (ORRs). Air respirators use high-pressure cylinders to store compressed air, while oxygen respirators are further divided into three categories based on the oxygen source: closed-loop oxygen respirators based on high-pressure oxygen cylinders, regenerative oxygen respirators based on potassium superoxide, and oxygen respirators based on sodium chlorate. A common feature of these respirators is the need to monitor and control key gas parameters (such as oxygen concentration, carbon dioxide concentration, gas temperature, and gas flow rate) to ensure the user's safety.

[0003] Air respirators use high-pressure cylinders (200-300 bar) to store compressed air, supplying it through pressure reducing valves and flow regulators. The supply flow rate is essentially fixed and cannot be dynamically adjusted. Closed-loop oxygen respirators based on high-pressure oxygen cylinders (such as the Dräger PSS series from Germany) use high-pressure oxygen cylinders as the oxygen source, achieving closed-loop circulation by absorbing carbon dioxide with quicklime. Their parameter control methods are basically the same as air respirators. Regenerative oxygen respirators based on potassium superoxide (such as the MSA Oxy-Respirator series from the USA) use potassium superoxide (KO2) as the oxygen generator, producing oxygen and absorbing carbon dioxide through the chemical reaction 4KO2 + 2CO2 → 2K2CO3 + 3O2. The oxygen production rate is determined by the breathing rate. The parameter monitoring methods for these three types of respirators are basically the same, mainly using mechanical or electronic pressure gauges to display the remaining gas pressure, triggering alarms when the cylinder pressure drops to a preset threshold via low-pressure alarm devices, and relying on diaphragm pressure changes to trigger mechanical switches for simple status indication. These monitoring methods are all passive designs, only providing alarms after problems occur, and cannot provide early warnings or proactive control. Some high-end products integrate electronic monitoring systems that can display information such as cylinder pressure and remaining protection time, but they still lack real-time monitoring of key parameters such as oxygen concentration, carbon dioxide concentration, gas temperature, and gas flow rate in the inhaled gas, and cannot provide early warning of the failure of carbon absorption devices or cooling devices.

[0004] While sodium chlorate-based oxygen respirators are widely used in emergency equipment due to their advantages such as small size, large oxygen storage capacity, and flexible storage conditions, existing commercially available products have serious shortcomings in parameter control and monitoring. Regarding parameter control, most products use a one-time ignition start-up method, making it impossible to maintain a constant oxygen production rate after startup. A few products use a mechanical oxygen replenishment trigger mechanism, relying on the degree of airbag expansion or changes in pipeline pressure as trigger conditions, but this suffers from severe response lag, false triggering, and missed triggering problems. There is a lack of intelligent control algorithms based on multi-parameter fusion. Existing detection and control structures adapted to high-pressure cylinders cannot be directly applied to sodium chlorate respirators because the sodium chlorate reaction is irreversible and highly exothermic, requiring a completely different control approach. Regarding parameter monitoring, existing sodium chlorate respirators are basically in a state of no monitoring, completely lacking real-time monitoring of key parameters such as oxygen concentration, carbon dioxide concentration, gas temperature, and gas flow rate in the inhaled gas. Although the products are equipped with decarbonators and cooling devices, users cannot monitor their working status, cannot accurately predict the remaining protection time, and lack working data storage functions, which is not conducive to fault tracing and product optimization. Users are in a state of complete blind operation, unable to understand the working status of the equipment, and unable to proactively respond to emergencies. Summary of the Invention

[0005] To overcome the shortcomings of existing respiratory protection equipment in parameter control and monitoring, such as the inability to accurately predict remaining protection time and the lack of working data storage function, this invention provides a gas monitoring and control system and method based on a solid oxygen respirator.

[0006] This invention provides a gas monitoring and control system based on a solid oxygen respirator. The solid oxygen respirator, arranged sequentially along the gas path, includes an air inlet, a decarbonizer, an air bag, a solid oxygen source module, a purification tank, a cooler, and an air outlet. The solid oxygen source module consists of multiple fixed oxygen candles, each equipped with an independent electric igniter. The system also includes: a gas parameter monitoring module, located at corresponding monitoring points in the gas path of the solid oxygen respirator, including an oxygen concentration sensor, a carbon dioxide concentration sensor, a gas flow sensor, and a multi-point temperature sensor; and a central processing and control unit, whose signal input is connected to the signal output of the gas parameter monitoring module. The central processing and control unit is connected to a data storage module via a data transmission bus. The central processing and control unit is used for... The control logic is calculated based on the data collected by the gas parameter monitoring module, and control commands are output. The electric ignition execution module receives ignition control signals from the central processing and control unit at its signal input terminal, and its signal output terminal is electrically connected to each independent electric igniter to control each electric igniter to perform ignition start and stop actions. The human-machine interface terminal communicates with the central processing and control unit and has an internal energy storage lithium battery. The power management module is electrically connected to the energy storage lithium battery, electric ignition execution module, gas parameter monitoring module, central processing and control unit, and human-machine interface terminal to provide suitable operating voltage for each module. It integrates DC voltage conversion, energy storage lithium battery charge and discharge management, multi-branch power supply switching, and overvoltage, overcurrent, and overtemperature protection functions.

[0007] The carbon remover is located in the air passage between the air inlet and the airbag to remove carbon dioxide from exhaled air; the purification canister is located in the air passage between the solid oxygen source module and the airbag to remove impurity gases generated during the oxygen production of the solid oxygen candle; and the cooler is located in the air passage between the airbag and the air outlet.

[0008] The system described in this invention is functionally divided into five main components: a gas state parameter monitoring module, a central processing and control unit (MCU), a human-machine interface terminal, an electric ignition execution module, and a power management module. The gas state parameter monitoring module is responsible for real-time sensing of various gas state parameters in the gas path. The MCU uses an embedded main control chip as its computing core, completing multi-channel analog signal acquisition, multi-protocol sensor data interaction, control logic operations, data storage and writing, and ignition command output. The human-machine interface terminal enables visualization of equipment status and manual intervention. The electric ignition execution module controls the ignition start and stop actions of the solid oxygen source. The power management module provides a stable power supply for all components of the system.

[0009] The main control chip integrates program storage and runtime memory resources, and its hardware peripherals are equipped with multiple communication and acquisition interfaces such as UART, IIC, and SPI, which can be easily integrated with various sensors, display components, and external storage devices. Simultaneously, the chip supports multiple low-power operating modes to meet the needs of battery-powered portable equipment. The main control relies on general-purpose I / O pins to output logic levels, which drive power switching devices through isolation circuits to achieve controllable switching of the ignition power supply circuit.

[0010] The central processing and control unit has multiple sets of standardized external plug-ins, which are divided into interfaces such as human-machine terminal interface and gas state parameter monitoring module according to function. Each interface is partitioned and the power supply, grounding and various communication signal lines are defined in a standardized manner to realize standardized and quick plug-in assembly of external accessories.

[0011] Human exhaled air enters the solid oxygen respirator through the inlet. After carbon dioxide is removed by the decarbonizer, it flows into the air bag. The central processing and control unit, combined with real-time collected gas state parameters, outputs an ignition control signal to drive the electric igniter to ignite the oxygen-generating agent inside the solid oxygen source to produce oxygen. The newly generated oxygen first passes through a purification tank to remove impurities, and then passes through a gas parameter monitoring module to collect data on gas production temperature and gas flow rate. It is then sent into the air bag to be mixed with the decarbonized exhaled air to form "artificial air." Subsequently, the "artificial air" collects oxygen concentration, carbon dioxide concentration, and inlet temperature in the gas parameter monitoring module. After being cooled by a cooler to a temperature suitable for the user's breathing, it is supplied to the user for inhalation through the outlet.

[0012] Preferably, the oxygen concentration sensor is located in the gas path between the airbag and the cooler. The oxygen concentration sensor is an electrochemical sensing unit with a built-in temperature compensation circuit, and outputs oxygen concentration data through a standardized digital serial port. The carbon dioxide concentration sensor is located in the gas path between the airbag and the cooler. The carbon dioxide concentration sensor is a non-dispersive infrared sensing unit, and outputs measurement data through a general industrial serial port. The detection process is not affected by the ambient oxygen content. It is equipped with dual temperature compensation in both hardware and software, and the measurement range can cover the carbon dioxide concentration variation range of the closed-loop respirator under all operating conditions. The gas flow sensor is located in the gas path between the outlet of the solid oxygen source module and the airbag. The gas flow sensor is a MEMS thermal mass flow sensor chip, and outputs flow data through an IIC communication interface. The multi-point temperature sensor includes a first platinum resistance temperature measuring element located at the outlet of the solid oxygen source module, a second platinum resistance temperature measuring element located at the inlet of the cooler, and a third platinum resistance temperature measuring element located at the outlet of the cooler. Each platinum resistance temperature measuring element is connected to the central processing and control unit through an independent signal conditioning channel. The data acquisition principle is as follows: The central processing and control unit of the solid sample respirator is connected to the oxygen concentration sensor and the carbon dioxide concentration sensor via UART. After the oxygen concentration sensor and the carbon dioxide concentration sensor complete their data acquisition, they pull the voltage low and then continuously send data packets to the solid sample respirator at a specific baud rate. After sending, they pull the voltage high to complete the signal transmission. The central processing and control unit of the solid sample respirator is connected to the gas flow sensor via IIC. After the gas flow sensor completes its data acquisition, it pulls the voltage low and then continuously sends data packets to the solid sample respirator at a specific baud rate. After sending, it pulls the voltage high to complete the signal transmission. The first and second platinum resistance temperature measuring elements are used to detect the temperature at the outlet of the solid oxygen source module and the temperature at the inlet of the cooler, which is also the outlet of the airbag, respectively. After the high-temperature gas is cooled by the airbag, its temperature gradually decreases. The temperature changes detected by the first and second platinum resistance temperature measuring elements can be used for later product performance optimization and fault review.

[0013] The gas parameter monitoring module adopts an integrated modular design, with all types of sensors using standardized electrical interfaces and assembly specifications. The module integrates signal conditioning, filtering, noise reduction, and hardware temperature compensation circuitry. Multiple temperature sensors are deployed at key gas path nodes such as the solid oxygen outlet pipeline and the inlet and outlet of the cooler. All temperature measurement points are connected to the central processing and control unit to form a closed-loop temperature control link. This effectively addresses the technical problems of excessive heat release from the oxygen candle causing respiratory tract burns from inhaled gas and the lack of advance warning for cooling component failure.

[0014] Preferably, the human-machine interface terminal is equipped with a display unit and raised physical power, start, and emergency ignition buttons. The display unit shows oxygen concentration, carbon dioxide concentration, gas flow rate, gas temperature, remaining solid oxygen candle quantity, and overall operating time. The central processing and control unit transmits real-time operating data to the human-machine interface terminal via a serial communication link for display. This communication link also facilitates the transmission of power-on, start-up, and emergency start signals for the solid oxygen respirator. Simultaneously, changes in the main control pin level control the power switch circuit, sequentially managing the power supply to the corresponding electric igniter. The human-machine interface terminal uses an industrial-grade touchscreen or a near-eye display inside the mask to continuously refresh oxygen concentration, carbon dioxide concentration, gas flow rate, gas temperature, remaining solid oxygen quantity, and overall operating time. At the software level, data refresh priorities are defined, with critical safety parameters such as remaining oxygen supply and gas over-limit warnings being updated first to prevent data lag from misleading users. Raised physical buttons are included to facilitate blind operation while wearing protective gloves. A short press of the power button turns on the solid oxygen respirator, powering on the central processing and control unit and initializing all modules and the gas status parameter monitoring module, thus activating the device. A short press turns it off, executing the safety shutdown procedures for all sensors and actuators, saving necessary data to the data storage module, and then cutting off the power. The start button triggers the control program of the central processing and control unit, enabling the solid oxygen module to autonomously ignite and produce oxygen. If the user determines that emergency ignition is required, they can use the emergency ignition button to force ignition.

[0015] Preferably, the drive circuit of the electric ignition execution module includes an isolation circuit and an independent power supply circuit. The independent power supply circuit is connected to the ignition circuit via a lithium battery pack and a step-down circuit. A time-delay disconnect switch is connected in series in the drive circuit of the electric ignition execution module. The ignition action duration is equal to the delay duration of the time-delay disconnect switch, which disconnects the power supply to the ignition circuit after the ignition action is completed. The isolation circuit is used to isolate the impact of the large current during ignition. The independent power supply circuit ensures sufficient ignition energy. During ignition, the system outputs a fixed-duration ignition pulse signal according to the operating conditions. After the electric ignition execution module supplies power to the drive circuit, it ignites the ignition propellant, which then heats the solid oxygen candle to produce oxygen through a chemical reaction. The ignition action duration is equal to the delay duration of the time-delay disconnect switch, ensuring that the power supply to the ignition circuit is immediately cut off after the ignition action is completed, preventing damage to the circuit and electric ignition components from overheating due to prolonged power supply. Each ignition time is automatically written to the local storage log, and the remaining oxygen source quantity is updated synchronously.

[0016] Preferably, the power management module includes a lithium battery pack, a multi-stage voltage regulator circuit, a charge / discharge protection circuit, and a short-circuit / overcurrent protection circuit. The input of the multi-stage voltage regulator circuit is connected to the lithium battery pack, and the output of the multi-stage voltage regulator circuit is connected to the power supply terminals of each module in the system. The charge / discharge protection circuit and the short-circuit / overcurrent protection circuit are connected in the charge / discharge circuit of the lithium battery pack. A low-dropout voltage regulator is used to build the multi-stage voltage regulator circuit. The power management module can output the rated operating voltage adapted to each hardware module. The entire device is powered by a large-capacity energy storage lithium battery, and the power management module includes comprehensive overvoltage, overcurrent, and overtemperature hardware protection circuits. By combining the rated voltage and operating current of each module to calculate the overall power consumption, the theoretical battery life under full charge can be calculated.

[0017] Preferably, the data storage module is a removable external storage medium, and the storage area of ​​the data storage module stores full-time operating parameter data with timestamps. Four heterogeneous sensors with different output protocols—oxygen concentration, carbon dioxide concentration, gas flow rate, and multiple temperature channels—are uniformly connected to the main control acquisition bus. The system is equipped with a large-capacity external storage medium to archive full-time operating parameters with timestamps. This overcomes the shortcoming of traditional solid oxygen respirators lacking parameter recording functionality, enabling the viewing and traceability of data throughout the respirator's entire lifecycle, facilitating subsequent product performance optimization and fault analysis.

[0018] This invention also discloses a gas monitoring and control method based on a solid oxygen respirator, which is implemented based on the gas monitoring and control system based on a solid oxygen respirator described in this invention. The steps are as follows:

[0019] S1. Parameter Acquisition:

[0020] The solid oxygen respirator is powered on via the power button on the human-machine interface terminal. The central processing and control unit is powered on and initializes each module, and the device is activated. When the start button is pressed, the central processing and control unit outputs an ignition control signal, and the electric igniter of one of the unused solid oxygen candles performs the ignition operation, and the burning solid oxygen candle produces oxygen. At the same time, the central processing and control unit controls the gas parameter monitoring module to synchronously collect the oxygen concentration value and instantaneous gas flow value in the gas circuit of the solid oxygen respirator, and synchronously records the cumulative running time of the device according to the built-in timer of the central processing and control unit.

[0021] S2, Level 1 Judgment:

[0022] The oxygen concentration value is compared with the preset safety threshold. If the oxygen concentration value is ≥21%, the current environment is determined to be oxygen-rich. The central processing and control unit forcibly locks the start output of the electric igniter and does not perform the ignition operation, returning to step S1 to continue monitoring. If the oxygen concentration value is <21%, the current environment is determined to be oxygen-deficient, and the process proceeds to step S3.

[0023] S3, Level 2 Judgment:

[0024] Based on the determination of an oxygen deficiency state, the operating conditions are further differentiated according to the instantaneous gas flow rate. If the instantaneous gas flow rate is equal to the design threshold, it is determined to be a state of no breathing flow, indicating that the solid oxygen candle is not producing oxygen normally or the oxygen production is interrupted. Press the emergency ignition button on the human-machine interface terminal briefly, and the central processing and control unit will output an ignition control signal to start an unused solid oxygen candle to supplement oxygen. After the execution is completed, return to step S1. If the instantaneous gas flow rate is greater than the design threshold, it is determined to be a state of breathing flow, indicating that the solid oxygen candle has produced oxygen but the oxygen concentration is insufficient, and proceed to step S4.

[0025] S4, Level 3 Judgment:

[0026] In the case of oxygen deficiency and gas flow, a comprehensive judgment is made based on the cumulative running time of the equipment. If the cumulative running time of the equipment is ≤15 minutes, it is determined that the equipment is in the initial stage of startup, which is the natural reaction observation period of the solid oxygen candle. Ignition is not performed, and the process returns to step S1 to continue monitoring. If the cumulative running time of the equipment is >15 minutes, it is determined that the solid oxygen candle has reacted sufficiently but still cannot meet the oxygen supply demand. The central processing and control unit outputs an ignition control signal to start an unused solid oxygen candle for oxygen replenishment. After the process is completed, the process returns to step S1.

[0027] S5, Execute in a loop:

[0028] Repeat steps S1 to S4 above until all solid oxygen candles in the solid oxygen source module are depleted or the equipment is shut down.

[0029] The gas monitoring and control method based on a solid oxygen respirator described in this invention follows a three-stage pipeline model of "full-parameter perception, highly reliable decision-making, and precise execution." At the perception level, the gas monitoring and control system synchronously collects multi-dimensional gas parameter data (oxygen, carbon dioxide, flow rate, and temperature) through multiple protocol interfaces. At the decision-making level, an embedded real-time logic algorithm is run to fuse and analyze the collected data, accurately determining the working status of the solid oxygen respirator. At the execution level, precise level signals are output to control the high-current drive circuit, and the human-machine interface is simultaneously refreshed to achieve visualization of the status and immediate feedback on operations, thus forming a highly efficient and collaborative intelligent whole.

[0030] The method described in this invention abandons the traditional crude control method that relies on air pressure and mechanical device action triggering, and establishes a multi-dimensional joint judgment criterion control algorithm of "gas concentration-gas flow rate-running time" to overcome the problems of mechanical triggering gas replenishment lag and false triggering, and solve the industry blind spots of the inability to quantitatively monitor the consumption status of decarbonizer consumables, ineffective consumption of reagents, and poor oxygen supply matching.

[0031] Preferably, in S3, when the emergency ignition button on the human-machine interface terminal is pressed briefly, the central processing and control unit receives the signal and prompts whether to confirm ignition through the display unit of the human-machine interface terminal. After the user confirms and presses the emergency ignition button briefly again, the central processing and control unit outputs an ignition control signal.

[0032] Preferably, in S1, while the central processing and control unit controls the gas parameter monitoring module to collect oxygen concentration and instantaneous gas flow rate, it also monitors the temperature data at the outlet of the solid oxygen source module, the inlet of the cooler, and the outlet of the cooler in real time. When the temperature at the outlet of the cooler exceeds the corresponding temperature threshold, the central processing and control unit controls the human-machine interface terminal to issue an over-temperature warning signal corresponding to the location.

[0033] Preferably, the central processing and control unit stores the full-time operating parameter data to the data storage module according to a fixed sampling period. The full-time operating parameter data includes the data collected by the gas parameter monitoring module, the cumulative operating time, the ignition time of each fixed oxygen candle, and the number of unused solid oxygen candles in the solid oxygen source module.

[0034] The technical solution provided by this invention has the following technical effects compared with the prior art:

[0035] This technology effectively fills the technological gap in the field of intelligent closed-loop control of solid oxygen respirators, realizing full-process digital monitoring of key gas parameters of the entire machine. Relying on multi-parameter fusion electronic algorithms to complete operating condition judgment and action output, the execution accuracy of ignition control and over-temperature warning is significantly improved compared to traditional mechanical products. It can accurately match the oxygen supply rhythm according to user needs, effectively reducing solid oxygen agent waste. The entire hardware architecture revolves around the unique characteristics of the exothermic reaction and irreversible chemical reaction of solid oxygen, specifically designing a solid oxygen module composed of multiple short-time oxygen-generating solid oxygen candles, fundamentally solving the industry problem that existing gaseous oxygen control solutions cannot adapt to solid oxygen sources. The equipment relies on multi-point temperature measurement and real-time monitoring of multi-component atmospheres to achieve early warning of high temperature and decarbonant failure, reducing the risk of respiratory burns and carbon dioxide poisoning for users from the source. Simultaneously, the full-cycle operation data retention function enables traceability of equipment operating conditions, providing complete data support for subsequent product performance iterations and fault diagnosis. Attached Figure Description

[0036] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with the invention and, together with the description, serve to explain the principles of the invention.

[0037] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, for those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0038] Figure 1 This is a schematic diagram of the structure of a gas monitoring and control system based on a solid oxygen respirator according to a certain embodiment of the present invention;

[0039] Figure 2 This is a hardware system framework diagram of a gas monitoring and control system based on a solid oxygen respirator according to a certain embodiment of the present invention;

[0040] Figure 3 This is an electrical schematic diagram of a gas monitoring and control system based on a solid oxygen respirator according to a certain embodiment of the present invention;

[0041] Figure 4 This is a schematic diagram of data transmission between the oxygen concentration sensor and the carbon dioxide concentration sensor in a certain embodiment of the present invention;

[0042] Figure 5 This is a schematic diagram illustrating the data acquisition principle of the gas flow sensor in a certain embodiment of the present invention.

[0043] In the diagram: 1. Air inlet; 2. Decarbonizer; 3. Airbag; 4. Solid oxygen source module; 5. Purification tank; 6. Refrigerator; 7. Air outlet; 8. Electric igniter; 9. Oxygen concentration sensor; 10. Carbon dioxide concentration sensor; 11. Gas flow sensor; 12. Temperature sensor; 13. Central processing and control unit; 14. Electric ignition execution module; 15. Human-machine interface terminal; 16. Power management module. Detailed Implementation

[0044] To better understand the above-mentioned objectives, features, and advantages of the present invention, the solutions of the present invention will be further described below. It should be noted that, unless otherwise specified, the embodiments of the present invention and the features thereof can be combined with each other.

[0045] In this description, it should be noted that the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance. It should also be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," and "joint" should be interpreted broadly. For example, they can refer to fixed connections, detachable connections, or integral connections; they can refer to mechanical connections or electrical connections; they can refer to direct connections or indirect connections through an intermediate medium; and they can refer to the internal connection between two components. Those skilled in the art can understand the specific meaning of the above terms according to the specific circumstances.

[0046] Many specific details are set forth in the following description in order to provide a full understanding of the invention, but the invention may also be practiced in other ways different from those described herein; obviously, the embodiments in the specification are only some embodiments of the invention, and not all embodiments.

[0047] The specific embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

[0048] In one embodiment, such as Figure 1 , Figure 2 and Figure 3 As shown, a gas monitoring and control system based on a solid oxygen respirator is disclosed. The solid oxygen respirator, arranged sequentially along the gas path, includes an air inlet 1, a decarbonizer 2, an air bag 3, a solid oxygen source module 4, a purification tank 5, a cooler 6, and an air outlet 7. The solid oxygen source module 4 consists of multiple fixed oxygen candles, each equipped with an independent electric igniter 8. The system also includes: a gas parameter monitoring module, located at corresponding monitoring points in the gas path of the solid oxygen respirator, including an oxygen concentration sensor 9, a carbon dioxide concentration sensor 10, a gas flow sensor 11, and a multi-point temperature sensor 12; and a central processing and control unit 13, whose signal input terminal is connected to the signal output terminal of the gas parameter monitoring module. The central processing and control unit 13 is connected to a data storage module via a data transmission bus. The system is used to perform control logic calculations based on data collected by the gas parameter monitoring module and output control commands; the electric ignition execution module 14 receives ignition control signals from the central processing and control unit 13 at its signal input terminal and is electrically connected to each independent electric igniter 8 at its signal output terminal to control each electric igniter 8 to perform ignition start and stop actions; the human-machine interface terminal 15 is communicatively connected to the central processing and control unit 13 and has an internal energy storage lithium battery; the power management module 16 is electrically connected to the energy storage lithium battery, the electric ignition execution module 14, the gas parameter monitoring module, the central processing and control unit 13, and the human-machine interface terminal 15 to provide suitable operating voltages for each module and integrates DC voltage conversion, energy storage lithium battery charging and discharging management, multi-branch power supply switching, and overvoltage, overcurrent, and overtemperature protection functions.

[0049] Carbon remover 2 is installed in the air passage between air inlet 1 and air bag 3 to remove carbon dioxide from exhaled gas; purification tank 5 is installed in the air passage between solid oxygen source module 4 and air bag 3 to remove impurity gases generated during oxygen production by solid oxygen candle; cooler 6 is installed in the air passage between air bag 3 and air outlet 7.

[0050] The system described in this invention is functionally divided into five main components: a gas state parameter monitoring module, a central processing and control unit 13 (MCU), a human-machine interface terminal 15, an electric ignition execution module 14, and a power management module 16. The gas state parameter monitoring module is responsible for real-time sensing of various gas state parameters in the gas path. The central processing and control unit 13 uses an embedded main control chip as its computing core to complete multi-channel analog signal acquisition, multi-protocol sensor data interaction, control logic operations, data storage and writing, and ignition command output. The human-machine interface terminal 15 enables visualization of equipment status and manual intervention. The electric ignition execution module 14 controls the ignition start and stop actions of the solid oxygen source. The power management module 16 provides a stable power supply guarantee for all components of the system.

[0051] The main control chip integrates program storage and runtime memory resources, and its hardware peripherals are equipped with multiple communication and acquisition interfaces such as UART, IIC, and SPI, which can be easily integrated with various sensors, display components, and external storage devices. Simultaneously, the chip supports multiple low-power operating modes to meet the needs of battery-powered portable equipment. The main control relies on general-purpose I / O pins to output logic levels, which drive power switching devices through isolation circuits to achieve controllable switching of the ignition power supply circuit.

[0052] The central processing and control unit 13 has multiple sets of standardized external plug-ins reserved on the body. According to the function, they are divided into interfaces such as human-machine terminal interface and gas state parameter monitoring module. Each interface is partitioned and the power supply, grounding and various communication signal lines are defined in a standardized manner to realize standardized and quick plug-in assembly of external accessories.

[0053] Human exhaled air enters the solid oxygen respirator through inlet 1. After carbon dioxide is removed by decarbonizer 2, it flows into air bag 3. The central processing and control unit 13, based on real-time collected gas state parameters, outputs an ignition control signal to drive electric igniter 8 to ignite the oxygen-generating agent inside the solid oxygen source to generate oxygen. The newly generated oxygen first passes through purification tank 5 to remove impurities, and then passes through gas parameter monitoring module to collect data on gas production temperature and gas flow rate. It is then sent into air bag 3 to be mixed with the decarbonized exhaled air to form "artificial air". Subsequently, the "artificial air" collects oxygen concentration, carbon dioxide concentration, and inlet temperature in the gas parameter monitoring module. After being cooled by cooler 6 to a temperature suitable for the user's breathing, it is supplied to the user for inhalation through outlet 7.

[0054] Based on the above embodiments, in a preferred embodiment, such as Figure 4 and Figure 5As shown, oxygen concentration sensor 9 is located in the gas path between airbag 3 and cooler 6. Oxygen concentration sensor 9 is an electrochemical sensing unit with a built-in temperature compensation circuit, and outputs oxygen concentration data via a standardized digital serial port. Carbon dioxide concentration sensor 10 is located in the gas path between airbag 3 and cooler 6. Carbon dioxide concentration sensor 10 is a non-dispersive infrared sensing unit, and outputs measurement data via a general industrial serial port. The detection process is unaffected by ambient oxygen content, and it features dual temperature compensation in both hardware and software. The measurement range can cover carbon dioxide concentration changes under all operating conditions of the closed-circuit respirator. The gas flow sensor 11 is located in the gas path between the outlet of the solid oxygen source module 4 and the air bag 3. The gas flow sensor 11 is a MEMS thermal mass flow sensor chip and outputs flow data through an IIC communication interface. The multi-point temperature sensor 12 includes a first platinum resistance thermometer located at the outlet of the solid oxygen source module 4, a second platinum resistance thermometer located at the inlet of the cooler 6, and a third platinum resistance thermometer located at the outlet of the cooler 6. Each platinum resistance thermometer is connected to the central processing and control unit 13 via an independent signal conditioning channel. The acquisition principle is as follows: the central processing and control unit 13 of the solid sample respirator is connected to the oxygen concentration sensor 9 and the carbon dioxide concentration sensor 10 via UART. After the oxygen concentration sensor 9 and the carbon dioxide concentration sensor 10 complete their data acquisition, they pull the level low and then continuously send data packets to the solid sample respirator at a specific baud rate. After sending, the level is pulled high to complete the signal transmission. The central processing and control unit 13 of the solid sample respirator is connected to the gas flow sensor 11 via IIC. After the gas flow sensor 11 completes the data acquisition, it pulls the level low and then continuously sends data packets to the solid sample respirator at a specific baud rate. After the data transmission is completed, it pulls the level high to complete the signal transmission.

[0055] The gas parameter monitoring module adopts an integrated modular design, with all types of sensors using unified electrical interfaces and assembly specifications. The module integrates signal conditioning, filtering and noise reduction, and hardware temperature compensation circuitry. Multiple temperature sensors 12 are deployed at key gas path nodes such as the solid oxygen outlet pipeline and the inlet and outlet of the cooler 6. All temperature measurement points are connected to the central processing and control unit 13 to form a closed-loop temperature control link. This effectively addresses the technical problems of the oxygen candle's intense exothermic reaction causing overheating and respiratory tract burns from inhaled gas, and the lack of prior warning for cooling component failure.

[0056] Based on the above embodiments, in a preferred embodiment, the human-machine interface terminal 15 is equipped with a display unit and raised physical power buttons, start buttons, and emergency ignition buttons. The display unit displays oxygen concentration, carbon dioxide concentration, gas flow rate, gas temperature, remaining solid oxygen candle quantity, and overall machine operating time. The central processing and control unit 13 transmits real-time equipment operation data to the human-machine interface terminal 15 via a serial communication link for screen display. This communication link is also used to transmit power-on, start-up, and emergency start signals for the solid oxygen respirator. Simultaneously, changes in the main control pin level control the power switch circuit to control the power supply to the corresponding electric igniter 8. The human-machine interface terminal 15 uses an industrial-grade touchscreen display or a near-eye display inside the mask to continuously refresh oxygen concentration, carbon dioxide concentration, gas flow rate, gas temperature, remaining solid oxygen quantity, and overall machine operating time. At the software level, data refresh priorities are defined, with key safety parameters such as remaining oxygen supply and gas over-limit warnings being updated first to prevent data lag from misleading users. Raised physical buttons are provided to facilitate blind operation while wearing protective gloves. A short press of the power button turns on the solid oxygen respirator, powering on the central processing and control unit 13 and initializing all modules and the gas status parameter monitoring module, thus activating the device. A short press turns it off, and the central processing and control unit 13 executes the safety shutdown procedures for each sensor and actuator, saves necessary data to the data storage module, and then cuts off the power. The start button triggers the control program of the central processing and control unit 13, enabling the solid oxygen module to autonomously ignite and generate oxygen. If the user determines that emergency ignition is required, they can use the emergency ignition button to force ignition.

[0057] Based on the above embodiments, in a preferred embodiment, the drive circuit of the electric ignition execution module 14 is equipped with an isolation circuit and an independent power supply circuit. The independent power supply circuit is connected to the ignition circuit via a lithium battery pack and a step-down circuit. A time-delay disconnect switch is connected in series in the drive circuit of the electric ignition execution module 14. The ignition action duration is equal to the delay duration of the time-delay disconnect switch, which is used to disconnect the power supply to the ignition circuit after the ignition action is completed. The isolation circuit is to isolate the impact of the large current at the moment of ignition. The independent power supply circuit is set to ensure sufficient ignition energy. During ignition, the system outputs an ignition pulse signal of fixed duration according to the operating conditions. After the electric ignition execution module 14 is powered to the drive circuit, it ignites the ignition propellant, which then heats the solid oxygen candle to produce oxygen through a chemical reaction. The ignition action duration is equal to the delay duration of the time-delay disconnect switch, ensuring that the power supply to the ignition circuit is cut off immediately after the ignition action is completed, preventing the circuit and electric ignition components from being damaged by overheating due to prolonged power supply. Each ignition time is automatically written to the local storage log, and the remaining oxygen source quantity is updated synchronously.

[0058] Based on the above embodiments, in a preferred embodiment, the power management module 16 includes a lithium battery pack, a multi-stage voltage regulator circuit, a charge / discharge protection circuit, and a short-circuit overcurrent protection circuit. The input terminal of the multi-stage voltage regulator circuit is connected to the lithium battery pack, and the output terminal of the multi-stage voltage regulator circuit is connected to the power supply terminals of each module in the system. The charge / discharge protection circuit and the short-circuit overcurrent protection circuit are connected in the charge / discharge circuit of the lithium battery pack. By using low-dropout voltage regulator devices to build the multi-stage voltage regulator circuit, the power management module 16 can output the rated operating voltage adapted to each hardware module. The entire device relies on a large-capacity energy storage lithium battery for power supply. The power management module 16 also includes a complete overvoltage, overcurrent, and overtemperature hardware protection circuit. By combining the rated voltage and operating current of each module to calculate the overall power consumption, the theoretical battery life under full charge conditions can be calculated.

[0059] Based on the above embodiments, in a preferred embodiment, the data storage module is a removable external storage medium. The storage area of ​​the data storage module stores full-time operating parameter data with timestamps. Four heterogeneous sensors with different output protocols—oxygen concentration, carbon dioxide concentration, gas flow rate, and multiple temperature channels—are uniformly connected to the main control acquisition bus. The system is equipped with a large-capacity external storage medium to archive full-time operating parameters with timestamps. This addresses the shortcoming of traditional solid oxygen respirators lacking parameter recording functionality, enabling the viewing and traceability of data throughout the respirator's entire lifecycle, facilitating subsequent product performance optimization and fault analysis.

[0060] One embodiment also discloses a gas monitoring and control method based on a solid oxygen respirator, which is implemented based on the gas monitoring and control system based on a solid oxygen respirator described in this invention. The steps are as follows:

[0061] S1. Parameter Acquisition:

[0062] The solid oxygen respirator is powered on by the power button on the human-machine interface terminal 15. The central processing and control unit 13 is powered on and initializes each module, and the device is activated. When the start button is pressed, the central processing and control unit 13 outputs an ignition control signal, and the electric igniter 8 of one of the unused solid oxygen candles performs the ignition operation, and the burning solid oxygen candle produces oxygen. At the same time, the central processing and control unit 13 controls the gas parameter monitoring module to synchronously collect the oxygen concentration value and instantaneous gas flow value in the gas circuit of the solid oxygen respirator, and synchronously records the cumulative running time of the device according to the built-in timer of the central processing and control unit 13.

[0063] S2, Level 1 Judgment:

[0064] The oxygen concentration value is compared with the preset safety threshold. If the oxygen concentration value is ≥21%, the current environment is determined to be oxygen-rich. The central processing and control unit 13 forcibly locks the start output of the electric igniter 8 and does not perform the ignition operation, and returns to step S1 to continue monitoring. If the oxygen concentration value is <21%, the current environment is determined to be oxygen-deficient, and the process proceeds to step S3.

[0065] S3, Level 2 Judgment:

[0066] Based on the determination of a hypoxic state, the operating conditions are further differentiated according to the instantaneous gas flow rate. If the instantaneous gas flow rate is equal to the design threshold, it is determined to be a state of no breathing flow, indicating that the solid oxygen candle is not producing oxygen normally or the oxygen production is interrupted. Press the emergency ignition button on the human-machine interface terminal 15 briefly, and the central processing and control unit 13 outputs an ignition control signal to start an unused solid oxygen candle to supplement oxygen. After the execution is completed, return to step S1. If the instantaneous gas flow rate is greater than the design threshold, it is determined to be a state of breathing flow, indicating that the solid oxygen candle has produced oxygen but the oxygen concentration is insufficient, and proceed to step S4.

[0067] S4, Level 3 Judgment:

[0068] In the case of oxygen deficiency and gas flow, a comprehensive judgment is made based on the cumulative running time of the equipment. If the cumulative running time of the equipment is ≤15 minutes, it is determined that the equipment is in the initial stage of startup, which is the natural reaction observation period of the solid oxygen candle. Ignition is not performed, and the process returns to step S1 to continue monitoring. If the cumulative running time of the equipment is >15 minutes, it is determined that the solid oxygen candle has reacted sufficiently but still cannot meet the oxygen supply demand. The central processing and control unit 13 outputs an ignition control signal to start an unused solid oxygen candle for oxygen replenishment. After the process is completed, the process returns to step S1.

[0069] S5, Execute in a loop:

[0070] Repeat steps S1 to S4 above until all solid oxygen candles in solid oxygen source module 4 are depleted or the equipment is shut down.

[0071] Table 1. Logic of the Multi-Dimensional Joint Criterion Control Algorithm

[0072]

[0073] The method described in this invention aims to balance the timeliness of oxygen supply with system stability, avoid unnecessary ignition and loss of oxygen candles, and ensure reliable ignition and oxygen supply when oxygen deficiency is critical and time conditions are met.

[0074] The gas monitoring and control method based on a solid oxygen respirator described in this invention follows a three-stage pipeline model of "full-parameter perception, highly reliable decision-making, and precise execution." At the perception level, the gas monitoring and control system synchronously collects multi-dimensional gas parameter data (oxygen, carbon dioxide, flow rate, and temperature) through multiple protocol interfaces. At the decision-making level, an embedded real-time logic algorithm is run to fuse and analyze the collected data, accurately determining the working status of the solid oxygen respirator. At the execution level, precise level signals are output to control the high-current drive circuit, and the human-machine interface is simultaneously refreshed to achieve visualization of the status and immediate feedback on operations, thus forming a highly efficient and collaborative intelligent whole.

[0075] The method described in this invention abandons the traditional crude control method that relies on air pressure and mechanical device action triggering, and establishes a multi-dimensional joint judgment control algorithm of "gas concentration-gas flow rate-running time" to overcome the problems of mechanical triggering gas replenishment lag and false triggering, and solve the industry blind spots of the inability to quantitatively monitor the consumption status of decarbonizer 2 consumables, ineffective consumption of reagents, and poor oxygen supply matching.

[0076] Based on the above embodiments, in a preferred embodiment, in S3, when the emergency ignition button of the human-machine interface terminal 15 is pressed briefly, the central processing and control unit 13 receives the signal and prompts whether to confirm ignition through the display unit of the human-machine interface terminal 15. After the user confirms and presses the emergency ignition button briefly again, the central processing and control unit 13 outputs the ignition control signal.

[0077] Based on the above embodiments, in a preferred embodiment, in S1, while the central processing and control unit 13 controls the gas parameter monitoring module to collect oxygen concentration value and instantaneous gas flow rate value, it also monitors the temperature data at the outlet of the solid oxygen source module 4, the inlet of the cooler 6 and the outlet of the cooler 6 in real time through the gas parameter monitoring module. When the temperature at the outlet of the cooler 6 exceeds the corresponding temperature threshold, the central processing and control unit 13 controls the human-machine interaction terminal 15 to issue an over-temperature warning signal corresponding to the location.

[0078] Based on the above embodiments, in a preferred embodiment, the central processing and control unit 13 stores the full-time operating parameter data to the data storage module according to a fixed sampling period. The full-time operating parameter data includes the data collected by the gas parameter monitoring module, the cumulative operating time, the ignition time of each fixed oxygen candle, and the number of unused solid oxygen candles in the solid oxygen source module 4.

[0079] The core protection of this technology revolves around the real-time acquisition of key gas parameters by multiple types of sensors, and the implementation of closed-loop monitoring and ignition control of solid oxygen respirators in conjunction with intelligent control algorithms. While the core concept remains unchanged, there are a variety of equivalent alternative implementation methods, all of which fall within the scope of protection of this technology.

[0080] At the sensor level, any similar sensing device capable of real-time acquisition of oxygen concentration, carbon dioxide concentration, gas flow rate, and gas path temperature can replace the sensing scheme selected in the embodiment; the control algorithm can replace the fixed threshold lookup logic with intelligent decision-making models such as fuzzy control, PID closed-loop regulation, and adaptive machine learning, dynamically adjusting the ignition control threshold based on historical usage data; the hardware main controller can be replaced with a general-purpose processor of different architectures; the human-machine interface terminal 15 can be replaced with different types of display devices as needed, and additional functions such as voice broadcast, vibration warning, and wireless remote mobile terminal control can be added; the local data storage medium can use onboard integrated storage elements to replace external storage cards, and the original limited data communication can be expanded to multiple wireless transmission methods to achieve remote cloud data upload; the power supply of the whole machine can be replaced with energy storage batteries of different chemical systems; the ignition power drive circuit can also use other switching devices of equivalent power to achieve the same on / off or isolation control function.

[0081] The above description is merely a specific embodiment of the present invention, enabling those skilled in the art to understand or implement the present invention. Although detailed descriptions have been provided with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments, and they should all be covered within the protection scope of the claims.

Claims

1. A gas monitoring and control system based on a solid oxygen respirator, wherein the solid oxygen respirator is provided with an air inlet (1), a decarbonizer (2), an air bag (3), a solid oxygen source module (4), a purification tank (5), a cooler (6), and an air outlet (7) in sequence along the gas path direction; the solid oxygen source module (4) is composed of multiple fixed oxygen candles, each solid oxygen candle being equipped with an independent electric igniter (8); characterized in that, Also includes: The gas parameter monitoring module is set at the corresponding monitoring points in the gas path of the solid oxygen respirator, including an oxygen concentration sensor (9), a carbon dioxide concentration sensor (10), a gas flow sensor (11), and a multi-point temperature sensor (12). The central processing and control unit (13) has its signal input terminal connected to the signal output terminal of the gas parameter monitoring module. The central processing and control unit (13) is connected to the data storage module through the data transmission bus. The central processing and control unit (13) is used to perform control logic operations based on the data collected by the gas parameter monitoring module and output control commands. The electric ignition execution module (14) receives the ignition control signal from the central processing and control unit (13) at its signal input terminal and is electrically connected to each independent electric igniter (8) at its signal output terminal to control each electric igniter (8) to perform ignition start and stop actions. The human-computer interaction terminal (15) is connected to the central processing and control unit (13) and is equipped with an energy storage lithium battery. The power management module (16) is electrically connected to the energy storage lithium battery, the electric ignition execution module (14), the gas parameter monitoring module, the central processing and control unit (13), and the human-machine interaction terminal (15), respectively. It is used to provide the appropriate working voltage for each module and integrates DC voltage conversion, energy storage lithium battery charging and discharging management, multi-branch power supply switching, and overvoltage, overcurrent, and overtemperature protection functions.

2. The gas monitoring and control system based on a solid oxygen respirator according to claim 1, characterized in that, An oxygen concentration sensor (9) is installed in the gas path between the airbag (3) and the cooler (6). The oxygen concentration sensor (9) is an electrochemical sensing unit with a built-in temperature compensation circuit, and outputs oxygen concentration data through a standardized digital serial port. A carbon dioxide concentration sensor (10) is installed in the gas path between the airbag (3) and the cooler (6). The carbon dioxide concentration sensor (10) is a non-dispersive infrared sensing unit, and outputs measurement data through a general industrial serial port. A gas flow sensor (11) is installed at the outlet of the solid oxygen source module (4). In the gas path between the end and the airbag (3), the gas flow sensor (11) is a MEMS thermal mass flow sensor chip, and outputs flow data through the IIC communication interface; the multi-point temperature sensor (12) includes a first platinum resistance temperature measuring element set at the outlet of the solid oxygen source module (4), a second platinum resistance temperature measuring element set at the inlet of the cooler (6) and a third platinum resistance temperature measuring element set at the outlet of the cooler (6), and each platinum resistance temperature measuring element is connected to the central processing and control unit (13) through an independent signal conditioning channel.

3. The gas monitoring and control system based on a solid oxygen respirator according to claim 2, characterized in that, The human-machine interaction terminal (15) is equipped with a display unit and raised physical power button, start button and emergency ignition button. The display unit is used to display oxygen concentration value, carbon dioxide concentration value, gas flow rate value, gas temperature value, remaining solid oxygen candle quantity and whole machine working time.

4. A gas monitoring and control system based on a solid oxygen respirator according to any one of claims 1 to 3, characterized in that, The drive circuit of the electric ignition execution module (14) is equipped with an isolation circuit and an independent power supply circuit. The independent power supply circuit is connected to the ignition circuit by the lithium battery pack through a step-down circuit. A time-delay disconnect switch is connected in series in the drive circuit of the electric ignition execution module (14). The ignition action duration is equal to the delay duration of the time-delay disconnect switch. The time-delay disconnect switch is used to disconnect the power supply to the ignition circuit after the ignition action is completed.

5. A gas monitoring and control system based on a solid oxygen respirator according to claim 4, characterized in that, The power management module (16) includes a lithium battery pack, a multi-stage voltage regulator circuit, a charge / discharge protection circuit, and a short-circuit overcurrent protection circuit. The input terminal of the multi-stage voltage regulator circuit is connected to the lithium battery pack, and the output terminal of the multi-stage voltage regulator circuit is connected to the power supply terminal of each module of the system. The charge / discharge protection circuit and the short-circuit overcurrent protection circuit are connected in the charge / discharge circuit of the lithium battery pack.

6. A gas monitoring and control system based on a solid oxygen respirator according to claim 5, characterized in that, The data storage module is a removable external storage medium, and the storage area of ​​the data storage module stores all-time operating parameter data according to timestamps.

7. A gas monitoring and control method based on a solid oxygen respirator, characterized in that, This is implemented based on the gas monitoring and control system of a solid oxygen respirator as described in claim 6, and its steps are as follows: S1. Parameter Acquisition: The solid oxygen respirator is powered on by the power button of the human-machine interface terminal (15). The central processing and control unit (13) is powered on and initializes each module, and the device is enabled. When the start button is pressed, the central processing and control unit (13) outputs an ignition control signal. The electric igniter (8) of one of the unused solid oxygen candles performs the ignition operation, and the burning fixed oxygen candle produces oxygen. At the same time, the central processing and control unit (13) controls the gas parameter monitoring module to synchronously collect the oxygen concentration value and instantaneous gas flow value in the gas path of the solid oxygen respirator, and synchronously records the cumulative running time of the device according to the built-in timer of the central processing and control unit (13). S2, Level 1 Judgment: The oxygen concentration value is compared with the preset safety threshold. If the oxygen concentration value is ≥21%, the current environment is determined to be oxygen-rich. The central processing and control unit (13) forcibly locks the start output of the electric igniter (8), does not perform the ignition operation, and returns to step S1 to continue monitoring. If the oxygen concentration value is <21%, the current state is determined to be oxygen-deficient, and step S3 is entered. S3, Level 2 Judgment: Based on the determination of hypoxia, the working conditions are further distinguished according to the instantaneous gas flow rate. If the instantaneous gas flow rate is equal to the design threshold, it is determined to be a state of no breathing flow, indicating that the solid oxygen candle is not producing oxygen normally or the oxygen production is interrupted. Press the emergency ignition button of the human-machine interface terminal (15) briefly, and the central processing and control unit (13) outputs the ignition control signal to start an unused solid oxygen candle to supplement oxygen. After the execution is completed, return to step S1. If the instantaneous gas flow rate is greater than the design threshold, it is determined to be a state of breathing flow, indicating that the solid oxygen candle has produced oxygen but the oxygen supply concentration is insufficient. Proceed to step S4. S4, Level 3 Judgment: In the case of oxygen deficiency and gas flow, a comprehensive judgment is made based on the cumulative running time of the equipment. If the cumulative running time of the equipment is ≤15min, it is determined that the equipment is in the initial stage of startup, which is the natural reaction observation period of the solid oxygen candle. Ignition operation is not performed, and the process returns to step S1 to continue monitoring. If the cumulative running time of the equipment is >15 minutes, it is determined that the solid oxygen candle has reacted sufficiently but still cannot meet the oxygen supply demand. The central processing and control unit (13) outputs an ignition control signal to start an unused solid oxygen candle to replenish oxygen. After the execution is completed, it returns to step S1. S5, Execute in a loop: Repeat steps S1 to S4 until all solid oxygen candles in the solid oxygen source module (4) are depleted or the device is shut down.

8. The gas monitoring and control method based on a solid oxygen respirator according to claim 7, characterized in that, In S3, when the emergency ignition button of the human-machine interface terminal (15) is pressed briefly, the central processing and control unit (13) receives the signal and prompts whether to confirm ignition through the display unit of the human-machine interface terminal (15). After the user confirms and presses the emergency ignition button briefly again, the central processing and control unit (13) outputs the ignition control signal.

9. A gas monitoring and control method based on a solid oxygen respirator according to claim 8, characterized in that, In S1, the central processing and control unit (13) controls the gas parameter monitoring module to collect oxygen concentration value and gas instantaneous flow rate value. At the same time, the gas parameter monitoring module also monitors the temperature data at the outlet of the solid oxygen source module (4), the inlet of the refrigerator (6), and the outlet of the refrigerator (6) in real time. When the temperature at the outlet of the refrigerator (6) exceeds the corresponding temperature threshold, the central processing and control unit (13) controls the human-machine interaction terminal (15) to issue an over-temperature warning signal corresponding to the location.

10. A gas monitoring and control method based on a solid oxygen respirator according to claim 9, characterized in that, The central processing and control unit (13) stores the full-time operating parameter data to the data storage module according to the fixed sampling period. The full-time operating parameter data includes the data collected by the gas parameter monitoring module, the cumulative operating time, the ignition time of each fixed oxygen candle, and the number of unused solid oxygen candles in the solid oxygen source module (4).

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