Mining positive-pressure anti-explosion cooperative mechanical arm and gas control system and method thereof

Abstract

The invention relates to the technical field of mining robot mechanical arms, in particular to a mining positive-pressure anti-explosion cooperative mechanical arm and a gas control system and method thereof. The mining positive-pressure anti-explosion cooperative mechanical arm gas control system comprises a gas source processing unit and a gas storage unit, gas is directly taken from a mine laneway environment through a gas pump, the concentration of methane in the gas is detected in real time through a methane gas sensor in a buffer cavity, and a circulating purification and waste discharge path is formed through an electromagnetic valve set; and it is ensured that only qualified gas is stored in the gas storage cavity. The whole machine adopts the vertical layout of the air cavity, the equipment cavity and the mechanical arm body, and the structure is compact; the control method comprises the steps of gas purification, purging, positive pressure maintaining and the like, and through multi-stage pressure sensing and closed-loop control, the stable positive pressure, 50 Pa higher than the ambient atmospheric pressure, in the equipment cavity is dynamically maintained. According to the invention, gas source self-supply in an underground explosive environment of a coal mine is realized, and the device has the advantages of high load self-weight ratio, small transformation degree and reliable operation.

Description

Technical Field

[0001] This invention relates to the field of mining robot arm technology, and in particular to a positive pressure explosion-proof collaborative robot arm for mining, and its gas control system and method. Background Technology

[0002] With the deepening of intelligent construction in coal mines, various intelligent equipment such as collaborative robotic arms have become key tools for improving production efficiency. However, the explosive gas mixtures such as methane (gas) and coal dust that are prevalent in the underground coal mine environment pose a serious explosion threat to all electrical equipment, including collaborative robotic arms.

[0003] To ensure safety, the equipment must comply with national explosion-proof standards (such as GB / T 3836-2021). Currently, the main explosion-proof types include flameproof, intrinsically safe, and pressurized types. For collaborative robotic arms, their application faces the following significant challenges: 1. Traditional explosion-proof designs are difficult to apply: Explosion-proof type: This type uses a heavy-duty explosion-proof structure to withstand internal explosion pressure. If this solution is applied to multi-joint collaborative robotic arms, each joint would require a heavy-duty explosion-proof shell, drastically increasing the arm's weight. Since collaborative robotic arms typically have a small load capacity (less than 50kg), the significant increase in the end-effector's mass will drastically reduce its effective load capacity, resulting in an extremely low load-to-weight ratio. Furthermore, the excessive inertia prevents it from meeting the flexibility and safety requirements of human-robot collaboration, rendering it impractical.

[0004] Intrinsically safe type: This type prevents sparks by limiting circuit energy, but its extremely low power limit cannot meet the power requirements of components such as drive motors in collaborative robotic arms, and therefore cannot be adopted.

[0005] 2. Limitations of existing positive pressure explosion-proof solutions: Positive pressure explosion-proof systems maintain an internal pressure higher than the external environment by continuously introducing clean protective gas into the equipment casing, thus preventing the entry of explosive gases and offering a potential direction for lightweight explosion-proof collaborative robotic arms. However, existing positive pressure explosion-proof solutions have significant drawbacks when applied to mobile equipment in underground coal mines: Difficulty in obtaining air supply: Existing positive pressure systems mostly rely on fixed compressed air pipeline networks or pre-stored compressed air cylinders. In coal mine roadways where space is limited and equipment needs to be moved, laying pipeline networks severely restricts the working range of the robotic arm, while using gas cylinders presents problems such as gas depletion, frequent replacement, and additional load, making it impossible to guarantee the continuous and autonomous operation of the robotic arm.

[0006] The structural modifications are complex: the closest existing technical solution involves adding a centralized isolation box to the collaborative robotic arm, removing all electrical components such as motors and control circuit boards from the joints and placing them in this isolation box for positive pressure protection. Power is then transmitted to each joint of the robotic arm via a transmission assembly. While this solution achieves positive pressure explosion protection, its drawbacks are extremely significant: (1) The main structure of the civilian collaborative robotic arm has been greatly modified, almost requiring a complete redesign, which is not conducive to the rapid standardization and promotion of the product. (2) The intermediate transmission link added between the drive motor and the robotic arm introduces additional transmission errors, backlash and energy loss, which significantly reduces the overall motion accuracy and transmission efficiency of the robotic arm.

[0007] Therefore, designing a positive pressure explosion-proof system that can adapt to the harsh environment of underground coal mines and achieve a continuous and reliable gas supply without significantly increasing the weight of the collaborative robotic arm or sacrificing its load-bearing capacity and motion accuracy has become a technical bottleneck that must be overcome to promote the large-scale application of collaborative robotic arms in the coal mining field. Summary of the Invention

[0008] The technical problem to be solved by this invention is: in order to solve the problem that the traditional explosion-proof type of the prior art is difficult to apply and the existing positive pressure explosion-proof solution has limitations, the present invention provides a gas control system for a mining positive pressure explosion-proof collaborative robotic arm, which combines a positive pressure explosion-proof type with a collaborative robotic arm, and introduces pure gas into the collaborative robotic arm so that the internal gas pressure is higher than the external explosive gas environment, thereby achieving explosion-proof treatment of the collaborative robotic arm in coal mines.

[0009] The technical solution adopted by the present invention to solve its technical problem is: a gas control system for a mining positive pressure explosion-proof collaborative robotic arm, including a gas source processing unit and a gas storage unit; The gas source processing unit includes an air pump for extracting gas from the mine roadway environment where the robotic arm is located, the inlet of the air pump being connected to the mine roadway environment; and a first solenoid valve, a second solenoid valve, a buffer chamber, and a third solenoid valve connected in sequence to the outlet side of the air pump via pipelines. The buffer chamber is equipped with a gas concentration detection unit for detecting the concentration of combustible gas inside; the first outlet of the third solenoid valve is connected to the inlet side pipeline of the air pump, forming a gas circulation and purification path; the second outlet of the third solenoid valve is used to discharge unqualified gas to the external environment. The gas storage unit includes a gas storage chamber, the inlet of which is connected to the overflow port of the second solenoid valve, for storing gas that has been determined to be qualified by the gas concentration detection unit; the gas storage chamber is arranged around the outer periphery of the buffer chamber.

[0010] The gas source processing unit actively extracts gas from the mine roadway environment and performs concentration detection through the buffer chamber to form a circulation purification path. At the same time, the gas storage unit stores qualified gas, realizing the gas self-sufficiency of the robotic arm in the explosive environment. This solves the problem that mobile devices have difficulty obtaining continuous and pure protective gas in underground coal mines. Meanwhile, the compact surrounding cavity design optimizes the system layout.

[0011] Furthermore, the gas concentration detection unit is a methane gas sensor, including one of a laser methane transmitter, a catalytic combustion methane sensor, or an infrared methane sensor.

[0012] By employing a high-precision, highly reliable, and interference-resistant methane gas sensor, the system ensures accurate identification of methane, a major hazardous gas in coal mines, providing reliable data support for the entire control process.

[0013] Furthermore, it also includes a control unit, which is electrically connected to the air pump, the first solenoid valve, the second solenoid valve, the third solenoid valve, and the gas concentration detection unit, and is used to control the passage status of each solenoid valve according to the detection result of the gas concentration detection unit.

[0014] By introducing a control unit and establishing its electrical connection and control relationship with the air pump, each solenoid valve and gas concentration detection unit, the gas purification supply process can be fully automated and intelligently closed-loop controlled. The system can make autonomous decisions and execute cyclic purification or waste discharge operations based on real-time sensor data, improving response speed, operating efficiency and overall reliability, and reducing manual intervention.

[0015] Furthermore, it also includes a fourth pressure detection unit for detecting the absolute pressure of the mine roadway environment. The fourth pressure detection unit is electrically connected to the control unit and is used to calculate and control the internal positive pressure value of the equipment cavity based on the absolute pressure of the environment detected by the fourth pressure detection unit.

[0016] Furthermore, the buffer cavity is also provided with a first pressure detection unit for detecting its internal pressure; the gas storage cavity is provided with a second pressure detection unit.

[0017] A first pressure detection unit is added to the buffer chamber to enhance the monitoring capability of the gas source processing unit's operating status. By monitoring the buffer chamber pressure, parameters are provided for judging the performance of the air pump, the unobstructedness of the pipeline, and the system's operating status, thereby improving the system's maintainability and fault early warning capability. A second pressure detection unit is added to the gas storage chamber to achieve real-time monitoring of the internal pressure of the gas storage unit, enabling the control system to accurately grasp the gas storage status and ensure the continuity and stability of the protective gas supply.

[0018] Also provided is a positive pressure explosion-proof collaborative robotic arm for mining, including: The gas control system for the mining positive pressure explosion-proof collaborative robotic arm described in the above scheme; The gas control system's gas pump, first solenoid valve, second solenoid valve, and third solenoid valve are housed within a device cavity. The buffer chamber and the gas storage chamber of the gas control system are disposed in a gas chamber, the gas storage chamber is disposed around the outer periphery of the buffer chamber, and the gas chamber is arranged below the equipment chamber; The main body of the collaborative robotic arm is positioned above the equipment cavity; The outlet of the gas storage chamber is connected in sequence to a pressure regulating valve and a speed regulating valve. The outlet of the speed regulating valve is connected to the equipment cavity through a fourth solenoid valve, which is used to supply and maintain a pure protective gas positive pressure to the equipment cavity; A third pressure detection unit is connected to the equipment cavity, and its outlet is connected in sequence to a one-way pressure valve and a flow detection unit.

[0019] A control method for the gas control system of the mining positive pressure explosion-proof collaborative robotic arm described in the above-mentioned scheme is also provided, including a gas purification step: Start the air pump and control the first, second and third solenoid valves to open, so that the gas flows along the outlet side of the air pump through the first and second solenoid valves into the buffer chamber, and then flows back to the inlet side of the air pump through the third solenoid valve to circulate. The concentration of combustibles in the gas within the buffer chamber is detected in real time by a gas concentration detection unit. When the gas concentration is detected to meet the requirements, the second solenoid valve is controlled to introduce a portion of the qualified gas into the gas storage chamber for storage. When the gas concentration is detected to be non-compliant, the third solenoid valve is controlled to discharge the non-compliant gas from the system through its second outlet.

[0020] Furthermore, in the gas purification step: if the gas concentration detection unit continuously detects that the gas is unqualified, it controls the gas pump to run continuously or intermittently, and controls the third solenoid valve to continuously discharge the unqualified gas until the gas concentration is detected to meet the requirements.

[0021] Limited to the gas purification process, the system's response strategy to continuously substandard gases establishes the system's absolute safety under extremely harsh operating conditions.

[0022] Furthermore, when the system starts up, a gas purification step is first performed until the gas storage chamber contains a sufficient amount of qualified gas, and then a positive pressure maintenance step is performed.

[0023] The system must be purified and then pressurized before startup to ensure its initial safety. This ensures that a pure positive pressure environment composed of qualified gas has been established inside the robotic arm's equipment cavity before it is powered on, meeting the core safety specifications of explosion-proof standards.

[0024] Furthermore, the positive pressure maintenance step is as follows: the qualified gas stored in the gas storage chamber is continuously supplied to the equipment chamber after being regulated by the pressure regulating valve and the speed regulating valve, so as to maintain the positive pressure inside the chamber.

[0025] The defined positive pressure maintenance step involves continuously supplying the stored qualified gas to the equipment cavity after pressure stabilization and speed regulation. This ensures the dynamic stability of the explosion-proof environment during long-term operation of the robotic arm. Through precise pressure and flow control, a stable and appropriate protective airflow is provided, which not only maintains an effective positive pressure barrier but also optimizes gas consumption, achieving a balance between safety and economy.

[0026] The beneficial effects of this invention are: The gas control system of this invention integrates ambient gas sampling, online detection, circulation purification, and intelligent storage and supply, successfully solving the three major problems of explosion protection for civilian collaborative robotic arms in the explosive environment of underground coal mines: By directly extracting air from the mine roadway environment and then buffering, testing, and circulating purification, the robotic arm is completely freed from its dependence on fixed compressed air pipelines or gas cylinders, realizing a self-sufficient and continuous supply of gas in hazardous environments, and overcoming the technical bottleneck of difficult gas source acquisition for mobile devices in complex roadways. By using a laser methane transmitter for high-precision real-time monitoring and combining it with the intelligent control of the solenoid valve group by the control unit, it is ensured that only qualified gas that has been rigorously verified can enter the system, thus eliminating the possibility of introducing dangerous gas into the explosion-proof cavity from the source. Compared to existing positive pressure solutions that centrally place the motor in an isolation box and drive it through a transmission component, this invention provides direct positive pressure protection to the cavity of the robotic arm body, thus preserving the original structure and transmission components of the civilian collaborative robotic arm to the greatest extent. This avoids efficiency losses, accuracy reductions, and structural complexity caused by adding transmission links, and truly achieves the goal of explosion-proof modification with high load-to-weight ratio, good motion accuracy, and minimal modification requirements.

[0027] In addition, the multi-level pressure and flow monitoring units set up in the system constitute a full-process safety monitoring system from gas source treatment and gas storage to cavity pressure maintenance, providing data support for predictive maintenance and intelligent management. Attached Figure Description

[0028] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0029] Figure 1This is a schematic diagram of the structure of the mining positive pressure explosion-proof collaborative robotic arm of the present invention.

[0030] Figure 2 yes Figure 1 A schematic diagram of the structure of the middle air chamber.

[0031] Figure 3 yes Figure 2 Sectional view along the AA direction.

[0032] Figure 4 This is a structural block diagram of the gas control system of the present invention.

[0033] Figure 5 This is a flowchart of the gas control method of the present invention.

[0034] In the diagram: 1. Air pump; 2. First solenoid valve; 3. Second solenoid valve; 4. Buffer chamber; 5. Gas concentration detection unit; 6. First pressure detection unit; 7. Gas storage chamber; 8. Second pressure detection unit; 9. Pressure regulating valve; 10. Speed ​​regulating valve; 11. Fourth solenoid valve; 12. Equipment chamber; 13. Third pressure detection unit; 14. One-way pressure valve; 15. Flow detection unit; 16. Third solenoid valve; 17. Collaborative robotic arm body; 18. Fourth pressure detection unit. Detailed Implementation

[0035] The present invention will now be described in further detail with reference to the accompanying drawings. These drawings are simplified schematic diagrams, illustrating only the basic structure of the invention, and therefore only show the components relevant to the invention.

[0036] Example 1 like Figure 1 As shown, a mining positive pressure explosion-proof collaborative robotic arm includes, from bottom to top, an air chamber, an equipment chamber 12, and a collaborative robotic arm body 17. The air chamber is located at the bottom of the entire device. Figure 2 and Figure 3 As shown, the gas chamber includes a gas storage chamber 7 and a buffer chamber 4, with the gas storage chamber 7 surrounding the outer periphery of the buffer chamber 4. This arrangement fully utilizes the radial space of the cylindrical cavity, tightly combining two cavities used for different functions, greatly improving space utilization efficiency and making the entire system very compact. Of course, other arrangements are also possible, as long as the two cavities are independent. The buffer chamber 4 is placed in the center as an independent detection unit, while the gas storage chamber 7 serves as its peripheral gas storage container.

[0037] The equipment cavity 12, acting as a connecting structure, is directly situated above the gas cavity, providing a relatively clean and centralized control environment. The collaborative robotic arm body 17 is fixedly mounted above the equipment cavity 12 via flanges or similar connection structures. The internal cavities of each joint of the robotic arm body 17 are connected to a positive pressure gas system (not fully shown in the figure) through pipes located inside the equipment cavity 12, thus filling its interior with protective gas as well.

[0038] This embodiment separates the functions of gas source processing, equipment control, and mechanical execution, making the structure more compact and easier to maintain and diagnose faults.

[0039] Example 2 like Figure 4 As shown, the gas control system for a mine-use positive pressure explosion-proof collaborative robotic arm comprises two main parts: a gas source processing unit and a gas storage unit. Its components are arranged in the equipment cavity 12 and the gas cavity, respectively, according to their functions. The gas source processing unit begins with the air pump 1. A suitable air pump 1 is selected by calculating the internal flow resistance of the robotic arm, preferably a piston-type or positive displacement air pump. This selection ensures sufficient power to overcome the flow resistance from subsequent pipelines, valves, and filter elements, and meets the requirement for rapid pressure build-up; it can also be set according to the internal resistance of the robotic arm.

[0040] The inlet of air pump 1 is directly connected to the mine roadway environment through a pipe and a filter (not shown in the figure). This means that the system actively inhales impure and dangerous gases containing complex components such as methane and coal dust. The inlet of air pump 1 is connected to the outlet (R port) of the first solenoid valve 2, and the outlet of air pump 1 is connected to the inlet (A port) of the second solenoid valve 3. The working port (R port) of the second solenoid valve 3 is connected to the inlet of the buffer chamber 4 located in the center of the air chamber through a pipe that passes through the bottom of the equipment chamber 12 and communicates with the air chamber.

[0041] A gas concentration detection unit 5 is installed inside the buffer chamber 4. In this embodiment, a mining intrinsically safe laser methane transmitter is preferably used. This device utilizes the principle of laser spectral absorption and has advantages such as high detection accuracy, fast response speed, strong anti-interference ability, and long life. The accuracy can reach ±1%FS, the response speed T90 < 3 seconds, and it is not affected by cross-interference from other gases. The alarm threshold of the laser methane transmitter is set to 1%LEL. When the system detects that the methane concentration in the air reaches 1%, the system will shut down. The buffer chamber 4 is also equipped with a first pressure detection unit 6, which is connected to the system backend as a monitoring parameter. The outlet of the buffer chamber 4 is connected to the inlet (port A) of the third solenoid valve 16. The first outlet (port R) of this solenoid valve flows back to the inlet side of the gas pump 1 through a pipeline, thus forming a gas circulation and purification path. Its second outlet (port P) is directly connected to the external environment for waste discharge. When the system starts, the gas flows through buffer chamber 4 and is detected. If the laser methane transmitter detects an excessive concentration, the control unit will command the third solenoid valve 16 to switch to the P-port open state. At this time, the substandard gas is directly discharged from the system, while the gas pump runs continuously or intermittently, constantly drawing in new gas for detection. This process will cycle indefinitely until qualified gas is detected, ensuring the quality of the gas source and preventing dangerous gas from entering subsequent stages.

[0042] When the gas is deemed qualified, the system controls the second solenoid valve 3 to open its P port (connecting ports A and P). At this time, the verified qualified gas passes through the P port and enters the gas storage chamber 7 of the gas storage unit for storage. The gas storage chamber 7 is equipped with a second pressure detection unit 8, which calculates the stored gas volume based on pressure and volume. The outlet of the gas storage chamber 7 is sequentially connected to a pressure regulating valve 9 and a speed regulating valve 10, used to adjust the high-pressure gas into a stable, low-speed airflow. Subsequently, the gas enters the equipment chamber 12 through the fourth solenoid valve 11. The outlet of the equipment chamber 12 is sequentially connected to a third pressure detection unit 13, a one-way pressure valve 14, and a flow detection unit 15. The one-way pressure valve 14 isolates the collaborative robotic arm from the external environment during normal operation, maintaining a positive pressure inside that is at least 50 Pa higher than the external atmospheric pressure. During purging, it ensures a one-way seal between the robotic arm's interior and the external environment, allowing the purging gas to flow in one direction. The flow detection unit 15 detects the purging flow rate to ensure it meets the requirements of the positive pressure protection system.

[0043] To achieve precise closed-loop control of the positive pressure value, the system also includes a fourth pressure detection unit 18, used to directly detect the absolute pressure of the mine roadway environment. The fourth pressure detection unit 18 is typically installed on the outer wall of the equipment cavity 12 or in any location that allows direct and undisturbed contact with the external atmosphere. The positive pressure maintained by the system is a relative pressure, while the third pressure detection unit 13 inside the equipment cavity 12 measures the absolute pressure. The control system calculates and adjusts the pressure in real time using the following formula: The target absolute pressure of the equipment cavity 12 = the ambient absolute pressure read by the fourth pressure detection unit 18 + the preset positive pressure value. The preset positive pressure value can be 50pa, or it can be set to other values ​​through the program. By introducing environmental pressure monitoring, the system can automatically compensate for atmospheric pressure fluctuations caused by factors such as mine depth, weather changes, and the start and stop of the ventilation system, ensuring that the effective positive pressure barrier applied to the outer shell of the equipment cavity 12 remains stable and reliable under any working conditions, eliminating the risk of unexpected increases or decreases in positive pressure value due to changes in environmental pressure.

[0044] Implementation Three like Figure 5 As shown, the gas control method for a positive pressure explosion-proof collaborative robotic arm in mining includes the following specific steps: Step 1: System Power-On Self-Test and Preparation: Power on the control unit, initialize the system, read data from each sensor, and confirm that there are no major faults; Step 2: Gas purification and storage: The control unit starts the air pump 1 and controls the first solenoid valve 2, the second solenoid valve 3, and the third solenoid valve 16 to be turned on to the circulation path. The gas begins to circulate, drawing gas from the external environment and entering the buffer chamber 4. The methane gas sensor 5 continuously detects the gas. When the gas is detected to be continuously substandard, the system will continuously control the air pump 1, the first solenoid valve 2, the second solenoid valve 3 and the third solenoid valve 16 to be connected to the circulation path, and always discharge waste through the P port of the third solenoid valve 16; during this process, the robotic arm is prohibited from being powered on, so that if the environment is not suitable for work, the system will wait indefinitely until the gas source is safe. When the gas is detected to be qualified and the pressure in the gas storage chamber reaches the upper limit, the system switches from the gas extraction mode to the storage mode. The gas is drawn into the gas storage chamber 7 by the gas pump 1 through the solenoid valve group. The system controls the second solenoid valve 3 to introduce the qualified gas into the gas storage chamber 7. The data from the first pressure detection unit 6 and the second pressure detection unit 8 are used to jointly determine whether the purification system is working normally and whether the gas storage is sufficient.

[0045] Step 3, Initial Purging: When the second pressure detection unit 8 confirms that the pressure in the gas storage chamber 7 has reached the preset value, the control unit opens the fourth solenoid valve 11 and keeps the third solenoid valve 16 in the circulation or closed state, and shuts down the air pump 1; the qualified gas in the gas storage chamber 7 is regulated by the pressure regulating valve 9 and the speed regulating valve 10, and enters the equipment chamber 12 at the set flow rate, and is finally discharged through the outlet flow detection unit 15.

[0046] Purging must continue until the total volume of pure gas filling equipment chamber 12 is greater than five times its internal empty volume. This technical requirement is directly derived from the national explosion-proof standard GB / T 3836.5-2021 "Explosive Atmospheres - Part 5: Equipment Protected by a Positive Pressure Enclosure 'P'" regarding "ventilation". Clause 6.3.2 of the standard explicitly stipulates that for PXB and PYB type positive pressure enclosures, the ventilation rate should be at least five times the net volume of the enclosure and its piping to ensure that the concentration of potentially flammable gas mixtures inside the enclosure is reduced to below a safe level. From an engineering fluid mechanics perspective, this five-times-volume requirement involves the forced replacement and dilution of the original gas by a sufficient amount of protective gas in a flowing state. Although the actual concentration decay process is complex, this empirical value is adopted by internationally recognized explosion-proof standards and has been verified through long-term practice, making it sufficient in engineering to ensure that the internal environment of the enclosure meets explosion-proof safety conditions after purging.

[0047] Step 4: Maintaining Positive Pressure and Monitoring Operation: After purging, the system switches to pressure-maintaining mode. The system precisely maintains the positive pressure inside the equipment cavity 12 at a level 50 Pa higher than the external environment. This value is the optimal balance point verified by rigorous fluid dynamics calculations and experiments. It can form a sufficient gas barrier, effectively blocking the infiltration of external dangerous gases according to Darcy's law and other seepage principles, without causing premature wear or damage to the dynamic sealing structures such as the rotary seal and cable seal of the robotic arm body 17 due to excessive pressure. At the same time, it can control the leakage loss of protective gas within an economically reasonable range. The system precisely maintains the positive pressure inside the equipment cavity 12 at a level 50 Pa higher than the external environment (it can be more strictly required to be 70 Pa, 100 Pa, or 200 Pa, but not too high). Relying on the environmental absolute pressure reference provided by the fourth pressure detection unit 18, the control system dynamically compares the absolute pressure inside the equipment cavity measured by the third pressure detection unit 13 with the absolute pressure of the external environment in real time. The difference is the actual positive pressure value. The system adjusts the gas supply flow rate through PID and other control algorithms to keep this difference constant at 50 Pa.

[0048] During the operation of the robotic arm, the third pressure detection unit 13 and the flow detection unit 15 perform real-time monitoring. If a continuous abnormal drop in pressure or an abnormal increase in flow is detected, it indicates a leak. The control unit will first attempt to start air replenishment. If the compensation is ineffective and the pressure drops to the minimum safe threshold, the system will immediately execute a power-off command to force the robotic arm to stop working and issue an alarm.

[0049] Suppose the robotic arm needs to enter a poorly ventilated recovery tunnel where methane levels occasionally exceed limits. After the robotic arm arrives at the location and is powered on, the robotic arm cannot start because the methane concentration in the tunnel is above 1% LEL. When the gas is continuously substandard, waste gas is continuously discharged. The operator in the control room can then know that the current environment is unsafe. After a certain period of time, the local ventilation improves and the methane concentration drops below the safe threshold. The system completes the storage of qualified gas within a few minutes. The system automatically performs a powerful purging of 5 times the volume to create an initial pure methane-free environment for the equipment chamber 12 and the robotic arm body 7.

[0050] The system enters the positive pressure maintenance and operation monitoring phase, providing continuous protection for the robotic arm with a stable positive pressure of 50Pa. The robotic arm then begins performing tasks such as disassembly, handling, and maintenance that can last for several hours. During this period, due to normal leakage, the system will intermittently replenish a small amount of gas from the gas storage chamber 7. The gas storage chamber 7 itself will also automatically replenish from the now-qualified ambient gas source when the pressure drops. The entire process is completed automatically without the need for manual intervention in gas source management.

[0051] Based on the above-described preferred embodiments of the present invention, and through the foregoing description, those skilled in the art can make various changes and modifications without departing from the inventive concept. The technical scope of this invention is not limited to the contents of the specification, but must be determined according to the scope of the claims.

Claims

1. A gas control system for a positive pressure explosion-proof collaborative robotic arm used in mining, characterized in that, Includes a gas source processing unit and a gas storage unit; The gas source processing unit includes an air pump (1) for extracting gas from the mine roadway environment where the robotic arm is located, the inlet of the air pump (1) being connected to the mine roadway environment; and a first solenoid valve (2), a second solenoid valve (3), a buffer chamber (4) and a third solenoid valve (16) connected in sequence to the outlet side of the air pump (1) via pipelines. The buffer chamber (4) is equipped with a gas concentration detection unit (5) for detecting the concentration of combustible gas inside it; the first outlet of the third solenoid valve (16) is connected to the inlet side pipeline of the air pump (1) to form a gas circulation purification path; the second outlet of the third solenoid valve (16) is used to discharge unqualified gas to the external environment. The gas storage unit includes a gas storage chamber (7), the inlet of which is connected to the overflow port of the second solenoid valve (3) for storing gas that has been determined to be qualified by the gas concentration detection unit (5); the gas storage chamber (7) is arranged around the outer periphery of the buffer chamber (4).

2. The gas control system for a mine-use positive pressure explosion-proof collaborative robotic arm according to claim 1, characterized in that, The gas concentration detection unit (5) is a methane gas sensor, including one of a laser methane transmitter, a catalytic combustion methane sensor, or an infrared methane sensor.

3. The gas control system for a mine-use positive pressure explosion-proof collaborative robotic arm according to claim 1, characterized in that, It also includes a control unit, which is electrically connected to the air pump (1), the first solenoid valve (2), the second solenoid valve (3), the third solenoid valve (16) and the gas concentration detection unit (5), and is used to control the passage status of each solenoid valve according to the detection result of the gas concentration detection unit (5).

4. The gas control system for a mine-use positive pressure explosion-proof collaborative robotic arm according to claim 3, characterized in that, It also includes a fourth pressure detection unit (18) for detecting the absolute environmental pressure in the mine roadway. The fourth pressure detection unit (18) is electrically connected to the control unit and is used to calculate and control the internal positive pressure value of the equipment cavity (12) based on the absolute environmental pressure detected by the fourth pressure detection unit (18).

5. The gas control system for a mine-use positive pressure explosion-proof collaborative robotic arm according to claim 1, characterized in that, The buffer chamber (4) is also provided with a first pressure detection unit (6) for detecting its internal pressure; the gas storage chamber (7) is provided with a second pressure detection unit (8).

6. A positive pressure explosion-proof collaborative robotic arm for mining, characterized in that, include: The gas control system for a mining positive pressure explosion-proof collaborative robotic arm as described in any one of claims 1 to 5; The gas control system includes an air pump (1), a first solenoid valve (2), a second solenoid valve (3), and a third solenoid valve (16), all located within a device cavity (12). The buffer chamber (4) and the gas storage chamber (7) of the gas control system are disposed in a gas chamber. The gas storage chamber (7) is disposed around the outer periphery of the buffer chamber (4), and the gas chamber is arranged below the equipment chamber (12). The collaborative robotic arm body (17) is positioned above the equipment cavity (12); The outlet of the gas storage chamber (7) is connected in sequence to a pressure regulating valve (9) and a speed regulating valve (10). The outlet of the speed regulating valve (10) is connected to the equipment cavity (12) through the fourth solenoid valve (11) to provide and maintain a pure protective gas positive pressure to the equipment cavity (12); A third pressure detection unit (13) is connected to the equipment cavity (12), and its outlet is connected in sequence to a one-way pressure valve (14) and a flow detection unit (15).

7. A control method for a gas control system based on the mining positive pressure explosion-proof collaborative robotic arm according to any one of claims 1 to 5, characterized in that, Includes gas purification steps: Start the air pump (1) and control the first solenoid valve (2), the second solenoid valve (3) and the third solenoid valve (16) to open, so that the gas flows along the outlet side of the air pump (1) through the first solenoid valve (2) and the second solenoid valve (3) into the buffer chamber (4), and then flows back to the inlet side of the air pump (1) through the third solenoid valve (16) for circulation. The concentration of combustibles in the gas in the buffer chamber (4) is detected in real time by the gas concentration detection unit (5); When the gas concentration is detected to meet the requirements, the second solenoid valve (3) is controlled to introduce part of the qualified gas into the gas storage chamber (7) for storage; When the gas concentration is detected to be non-compliant, the third solenoid valve (16) is controlled to discharge the non-compliant gas through its second outlet.

8. The gas control method for a mine-use positive pressure explosion-proof collaborative robotic arm according to claim 7, characterized in that, In the gas purification step: if the gas concentration detection unit (5) continuously detects that the gas is unqualified, the gas pump (1) is controlled to run continuously or intermittently, and the third solenoid valve (16) is controlled to continuously discharge the unqualified gas until the gas concentration is detected to meet the requirements.

9. The gas control method for a positive pressure explosion-proof collaborative robotic arm in mining according to claim 8, characterized in that, When the system is started, the gas purification step is performed first until the gas storage chamber (7) contains a sufficient amount of qualified gas, and then the positive pressure maintenance step is performed.

10. The gas control method for a mine-use positive pressure explosion-proof collaborative robotic arm according to claim 9, characterized in that, The positive pressure maintenance step is as follows: the qualified gas stored in the gas storage chamber (7) is continuously supplied to the equipment chamber (12) after being regulated by the pressure regulating valve (9) and the speed regulating valve (10) to maintain its internal positive pressure.

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