Refrigerating fire-fighting waistcoat based on positive pressure type fire-fighting respirator

Abstract

The invention belongs to the technical field of safety and protection, and relates to a refrigerating fire-fighting waistcoat based on a positive pressure type fire-fighting respirator. A traditional ice bag vest for firefighters has the defects of weight and activity limitation, poor comfort and safety, high maintenance and reuse cost, insufficient compatibility with firefighter uniform and the like. The specific structure of the fire-fighting waistcoat capable of refrigerating comprises a compressed air tank, a carbon fiber porous silicon heat insulation shell, a gas expansion chamber and the like. The working principle is that a water path in the fire-fighting waistcoat is cooled by using a gas expansion heat absorption principle so as to reduce the body temperature of a firefighter. The compressed air tank can contain 13.6 L of compressed air with the pressure of 30 Mpa, the alarm pressure is 5.5 Mpa, and the working time is about 20 minutes. Through calculation, the compressed air in the tank can absorb 697032 J heat from the working air pressure to the alarm air pressure, the waistcoat can be kept for about 11 minutes in the environment of 600 DEG C to stabilize 1 L of water at 20 DEG C, the waistcoat can be theoretically kept for about 40 minutes in the environment of 300 DEG C, and the specific duration needs to be tested for multiple times in a laboratory. The vest has the advantages that the positive pressure type respirator expands to absorb heat when releasing gas in the compression bottle, cooling of a water way in the vest is achieved, high-temperature heating of firemen is reduced, frostbite cannot be caused by uniform heat absorption, precooling does not need to depend on a refrigerator or a low-temperature environment, and the defect that a traditional ice bag vest is large in weight is further overcome to a certain degree.

Description

Technical Field

[0001] This invention relates to the field of safety and protection technology, and in particular to a refrigerated fire vest based on a positive pressure fire breathing apparatus. Background Technology

[0002] In fire and rescue operations, firefighters need to wear heavy protective suits to enter high-temperature environments. Traditionally, ice pack vests are used to lower body temperature. However, traditional firefighter ice pack vests have several drawbacks: Weight and Movement Restriction: Ice pack vests themselves contain cold storage bags and insulation layers, making them quite heavy. When firefighters wear these vests over their protective suits, the total load increases significantly, greatly affecting their mobility. According to the research paper "Optimization and Weight Reduction Design of Firefighter Personal Protective Equipment," the increased weight makes firefighters' movements sluggish during missions. Furthermore, traditional ice pack vests have ergonomic shortcomings; some vests are not securely fixed and tend to sway during firefighter movement. Referring to the analysis of load swaying in the Zhihu article "Exposure of PLA's New Tactical Carrying Vest," this swaying restricts tactical movements, increasing the difficulty and risk for firefighters. Comfort and Safety Issues: Moisture Issues: Ice packs gradually melt during use, and the melted ice water can easily dampen the inner layers of clothing. Prolonged contact with damp clothing may cause skin discomfort and even the risk of frostbite. The paper "Observation on the Cooling Effect of Ice Pack Fixing Bags and Traditional Ice Compress" elaborates on this issue in detail. Localized Overcooling: When the refrigerant comes into direct contact with the skin, if the insulation layer is not designed properly, it may lead to excessively low local temperatures, such as in the armpits or lower back. The analogy about the dangers of low temperatures in the online article "Is Ice Pack Cushion Good or Bad for the Body?" vividly illustrates the potential adverse effects of such localized overcooling. High Maintenance and Reuse Costs: Traditional ice pack vests require pre-cooling in refrigerators or low-temperature environments, making it difficult to quickly replenish the cold source in scenarios such as field rescues. Referring to the online article "What is a Firefighter's Cooling Vest and How to Use It?", this greatly limits the practical use of ice pack vests. Furthermore, the performance of the refrigerant decreases after repeated refilling and cooling. For example, with gel-type ice packs, the cooling efficiency significantly decreases after more than 100 pre-cooling cycles, undoubtedly increasing the cost of long-term use. Insufficient Compatibility with Firefighter Suit: Some traditional ice pack vests are not designed with sufficient consideration for the multi-layered structure of firefighter suits, such as the outer flame-retardant layer and the middle heat-insulating layer. This hinders heat dissipation, exacerbating the stuffiness inside firefighters' clothing after they wear ice pack vests and fire suits. A Zhihu answer stating "Fire suits are insulated; people will suffer heatstroke if they move around inside" reflects this issue. Furthermore, the fastening straps or Velcro of the ice pack vests may compromise the protective properties of the outer layer of the fire suit, for example, causing wear and tear on the flame-retardant coating and reducing the suit's protective effectiveness. Summary of the Invention

[0003] Purpose of the invention: The purpose of this invention is to provide a refrigerated fire vest based on a positive pressure fire breathing apparatus, so as to solve the problems of weight and activity restrictions, comfort and safety issues, high maintenance and reuse costs, and insufficient compatibility with fire suits of the traditional ice pack vest.

[0004] Structural Composition: The refrigerated fire vest based on a positive pressure fire breathing apparatus provided by this invention has the following specific structure (see attached instruction manual). Figure 1 1. Compressed Air Tank: Stores compressed air, providing the gas source for the entire refrigeration system. 2. Carbon Fiber Porous Silicone Insulation Shell: Encloses the compressed air tank, its main function being to effectively isolate external temperatures and reduce the impact of external heat on the compressed air tank and the internal gas. 3. Gas Expansion Chamber: Compressed air enters this chamber after being released from the compressed air tank for expansion. 4. Grid Cooling Copper Tubes: Located around the gas expansion chamber, these tubes absorb heat from the compressed air as it expands, thus achieving cooling. 5. Pressure Regulating Valve: Installed on the pipeline between the compressed air tank and the gas expansion chamber, it precisely regulates the gas pressure to ensure stable system operation. 6. Active Pressure Relief Valve: Connected to the gas expansion chamber, it automatically opens to release pressure and ensure system safety when the system pressure exceeds the safe range. 7. Gas Pipelines: Connect to various components to transmit compressed air. 8. Backplate and Fixing Straps: The backplate provides support for the entire device, while the fixing straps securely fasten the device to the firefighter's back. 9. Compressed Gas Pressure Gauge: Displays the real-time pressure inside the compressed air tank, allowing firefighters to monitor the gas supply status. 10. Face Mask: Connected to the gas pipeline for firefighters' breathing, ensuring they can breathe normally in high-temperature environments. 11. Cooling Water Output Vest Interface and 13. Cooling Water Input Interface: Connected to the cooling water pipeline inside the vest, forming a complete water circulation system. 12. Vest (including cooling water pipeline): Equipped with internal cooling water pipelines, it absorbs the cold energy from the grid cooling copper pipes to cool the firefighter's body.

[0005] Working Principle: This invention utilizes the principle of gas expansion and heat absorption to cool the water system inside the firefighter's vest, thereby lowering the firefighter's body temperature. Specifically, when a firefighter breathes, compressed air is released from the compressed air tank and enters the gas expansion chamber to expand. During expansion, the gas absorbs heat from the surrounding compressed air tank. The grid-cooled copper pipes transfer this cooling energy to the connected cooling water pipes inside the vest for secondary cooling. The circulating cooling water in these pipes carries away the heat generated by the firefighter's body, thus achieving a cooling effect.

[0006] Theoretical Support: The compressed air tank can hold 13.6L of compressed air at 30MPa, with an alarm pressure of 5.5MPa and an operating time of approximately 20 minutes. Calculations show that when the compressed gas in the tank is released from the operating pressure to the alarm pressure, it absorbs 697,032J of heat, with most of the heat being absorbed through the grid copper tubes. The porous silicon material used effectively insulates against external temperatures, reducing heat absorption by the gas. Calculations show that the refrigerated positive-pressure breathing apparatus can maintain a temperature of approximately 11 minutes at 600°C and stabilize 1L of water at 20°C. Considering that firefighters rarely come into direct contact with fire in actual work, theoretically, it can maintain a temperature of approximately 40 minutes at 300°C, but specific testing and verification are required in a rigorous laboratory setting. Beneficial Effects: Efficient Cooling and Safe Comfort: By utilizing the principle of heat absorption during the expansion of compressed gas released from the positive-pressure breathing apparatus, the water system inside the firefighter's vest is cooled, effectively reducing the heat exposure of firefighters in high-temperature environments. Furthermore, the positive pressure breathing apparatus absorbs heat evenly when releasing gas, preventing frostbite and other injuries to firefighters, greatly improving comfort and safety. No pre-cooling equipment required: Because this invention uses the even heat absorption method of the positive pressure breathing apparatus for cooling, it does not rely on refrigerators or low-temperature environments for pre-cooling. This allows the refrigerated fire vest to be used more flexibly in various rescue scenarios, especially in wilderness rescues, without being limited by the availability of cold sources. Reduced weight: It alleviates the disadvantage of the heavy overall weight of traditional ice pack vests to some extent. Compared to traditional ice pack vests, the refrigerated fire vest of this invention is designed to be lighter, reducing the extra weight carried by firefighters, improving their mobility, and helping them to better complete fire rescue missions. Attached Figure Description

[0007] Figure 1 is a 3D structural diagram of the components of a refrigerated fire vest based on a positive pressure fire breathing apparatus. 1. Compressed gas tank 2. Carbon fiber shell 3. Gas expansion chamber 4. Copper cooling grid 5. Passive pressure relief valve 6. Pneumatic water circulation pump 7. Gas pipeline 8. Carbon fiber back plate 9. Pressure gauge 10. Breathing mask 11. Interface for heat exchange with cooling vest

Claims

1. A refrigerated fire vest based on a positive pressure fire breathing apparatus, characterized in that, include: Compressed air tank, used to hold compressed air; A carbon fiber porous silicon heat insulation shell is used to enclose the compressed air tank, which serves to isolate it from the external temperature. The gas expansion chamber is connected to the compressed air tank, where the compressed air expands. The grid-cooled copper tubes are arranged around the gas expansion chamber for heat exchange with the expanding gas; A pressure regulating valve is installed on the pipeline between the compressed air tank and the gas expansion chamber to regulate the gas pressure. An active pressure relief valve, connected to the gas expansion chamber, ensures system pressure safety; Gas pipelines are used to connect various components and enable gas transmission; Backplate and securing straps are used to secure the entire device to the firefighter's back; A compressed gas pressure gauge is used to display the gas pressure inside a compressed air tank; The mask, connected to the gas tubing, is used by firefighters for breathing. The cooling water output port and the coolant input port are connected to the cooling water pipes inside the housing to form a water circulation. The vest has internal cooling water pipes that absorb the cold energy of the grid cooling copper pipes to achieve cooling.

2. The refrigerated fire vest based on a positive pressure fire breathing apparatus according to claim 1, characterized in that, The compressed air tank can hold 13.6L of compressed air at 30MPa, with an alarm pressure of 5.5MPa and an operating time of approximately 20 minutes.

3. The refrigerated fire vest based on a positive pressure fire breathing apparatus according to claim 1, characterized in that, Utilizing the principle of heat absorption during gas expansion, compressed air expands in the gas expansion chamber after being released from the gas tank, absorbing heat from the grid cooling copper tubes, thereby cooling the water channels inside the vest.

4. The refrigerated fire vest based on a positive pressure fire breathing apparatus according to claim 1, characterized in that, The carbon fiber porous silicon thermal insulation shell reduces heat absorption by the gas from the outside, allowing most of the heat to be obtained from the grid cooling copper tubes.

5. The refrigerated fire vest based on a positive pressure fire breathing apparatus according to claim 1, characterized in that, The refrigerated positive pressure respirator can maintain a temperature of approximately 11 minutes at 600°C and stabilize 1L of water at 20°C; theoretically, it can maintain a temperature of approximately 40 minutes at 300°C.

6. The refrigerated fire vest based on a positive pressure fire breathing apparatus according to claim 1, characterized in that, When the gas in the compressed cylinder is released by the positive pressure breathing apparatus, it expands and absorbs heat, thereby cooling the water circuit inside the firefighter's vest and reducing the heat received by the firefighter in the high-temperature environment. Moreover, the gas absorbs heat evenly when it is released, so it will not cause frostbite or other injuries to the firefighter's body.

7. The refrigerated fire vest based on a positive pressure fire breathing apparatus according to claim 1, characterized in that, It does not require refrigeration or pre-cooling in a low-temperature environment, which to some extent reduces the disadvantage of the large overall weight of traditional ice pack vests.

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