One-way water-permeable pressure-resistant aerial fire extinguishing bag easy to break when falling to ground

Abstract

The utility model discloses a one-way water-permeable pressure-resistant aerial fire extinguishing bag easy to break when falling to the ground, which comprises a fire extinguishing bag body and a fire extinguishing agent packaged in the fire extinguishing bag body, and also comprises a hydrophobic layer positioned between the fire extinguishing bag body and the fire extinguishing agent, and through holes positioned on the fire extinguishing bag body and the hydrophobic layer. And the loss of water in the bag when the fire extinguishing bag falls is reduced, the packaging strength of the fire extinguishing bag is ensured, and the fire extinguishing bag not only can keep enough pressure resistance under the proportion of the sealing edge, but also can be easily broken and exploded when falling to the ground.

Description

TECHNICAL FIELD

[0001] The utility model relates to forest aviation fire fighting technical field, concretely is a one -way water -permeable pressure -resistant landing easy breakage's aviation fire extinguishing bag. BACKGROUND

[0002] The main force of aviation forest fire fighting is fixed wing fire fighting aircraft. Taking the North American aviation forest fire fighting system as an example, the fixed wing fire fighting aircraft loaded with a large amount of fire extinguishing agent for fire prevention isolation belt layout often needs to follow the guide aircraft for low altitude operation, flying at a height of 100 to 300 meters, because of low altitude flight over the fire field, it is easy to be affected by hot air flow, terrain and smoke, and the flight risk is high. The fire extinguishing agent put out by the aircraft is also affected by fire wind field and high temperature, and is gasified or atomized and scattered, with a loss of 15% to 25%. The use of foam or gel fire extinguishing agent can reduce the loss. There are two types of products available to solve the problem of excessive dispersion of fire extinguishing agent or water in the air.

[0003] For example, the Chinese patent CN221867203U discloses a long-distance precision guided fire extinguishing bomb, which comprises a fire extinguishing bomb body and a mounting shell. An electric control assembly is arranged inside the mounting shell, which comprises a micro battery, a GPS positioning module, a rotating rod two, a rotating rod one, a torsion spring, an electromagnet two, a magnetic force column and a special nylon textile cloth. When adjusting the position, the electromagnet two can be opened to adsorb the magnetic force column, so that the rotating rod one can rotate under the torsion of the torsion spring, the special nylon textile cloth inside the mounting shell is pulled out to realize the double-wing sliding state, and the positioning is realized while the precision guidance is assisted. The utility model can realize the precision guidance after positioning, and is provided with an arc-shaped sliding groove, a spring two and a winding column. After the device is used, the rotating rod one is reset, and the winding column can still wind the special nylon textile cloth to ensure that the special nylon textile cloth is not affected by external air flow inside the mounting shell.

[0004] The technical scheme is to fill solid fire extinguishing powder into a hard shell bomb body. This type of product is the mainstream product on the market, mainly including spherical, hand grenade-shaped, bomb-shaped and missile-shaped four types, all of which are prefabricated fire extinguishing bombs. The fire extinguishing powder needs to be sealed in the bomb body in advance, and the bomb is detonated by preheating explosion or fuse explosion, and relies on the explosion impact and fire extinguishing powder for fire extinguishing. This type of fire extinguishing product has the following shortcomings:

[0005] 1. The bomb-shaped and missile-shaped bombs with fuses have high cost due to the installation of near-blast fuses, which is not conducive to large-scale use;

[0006] 2. The prefabricated fire extinguishing bomb bodies are made of hard shell materials, which occupy a large volume in the mounting and the launching cabin, and also need a large place for storage and transportation, with low space utilization rate;

[0007] 3. Among them, the fire extinguishing ball without a fuse needs to hit the fire source directly to explode and take effect. This requires the vehicle to be very close to the fire source, which makes the vehicle risky, the use more cumbersome, and there is a risk of explosion during storage.

[0008] 4. Most fire extinguishing bombs contain solid fire extinguishing powder that is not suitable for large-scale use, as it can easily cause eutrophication of water bodies and soil, thus affecting the environment.

[0009] For example, Chinese patent CN 118105653 discloses a self-filling fire extinguishing bag for aerial fire suppression. This self-filling fire extinguishing bag includes a bag body with an internal space, reinforcing ribs on the bag body, and / or rupture guide lines that guide the bag body to directional rupture. The internal space contains fire extinguishing agent, and the rupture guide lines are also arranged on the bag body. Additionally, a hydrophilic-hydrophobic gradient coating is applied to the bag body, making the bag body unidirectionally permeable to water from the outside to the inside. This self-filling fire extinguishing bag strengthens the bag body with reinforcing ribs to prevent accidental rupture and improve fire extinguishing efficiency; the rupture guide lines guide the rupture of the fire extinguishing bag, increasing rupture effectiveness and uniform distribution of the fire extinguishing agent; it achieves unidirectional water-permeable self-filling, meeting the flexible operational needs of firefighting aircraft and preventing fire extinguishing agent spillage and leakage; and by using polylactic acid material to make the fire extinguishing bag, it meets environmental protection requirements for forest fire fighting.

[0010] This technical solution uses a soft bag filled with water-based extinguishing agent. Two types of products are known, but they are not yet widely available on the market: one uses polylactic acid meltblown nonwoven fabric as the bag material, and the other uses biodegradable plastic. The extinguishing method relies on the bag bursting upon impact with the ground to release the extinguishing agent inside. This type of product has the following disadvantages:

[0011] 1. Products using biodegradable plastic bags need to be filled with extinguishing agent before use. If they are prefabricated, they are difficult to store. Filling requires large equipment, has high site requirements, and is difficult to use.

[0012] 2. Although the technical solution mentions using polylactic acid meltblown nonwoven fabric to package the product, it does not define in detail the sealing edge and sealing method used. The product states that all sealing edges can be used, but experiments have shown that only specific sealing methods and sealing edge configurations can meet the strength requirements of fire extinguishing bags. Utility Model Content

[0013] Purpose of the utility model: In order to overcome the shortcomings of the prior art, this utility model provides a one-way permeable, pressure-resistant, and easily ruptured aviation fire extinguishing bag. The bag structure is optimized, reducing the loss of water inside the bag during descent, ensuring the strength of the fire extinguishing bag packaging, and allowing the fire extinguishing bag to maintain sufficient pressure resistance under this sealing ratio, while still bursting open upon landing.

[0014] Technical scheme: In order to realize the above object, the utility model provides a one -way water -permeable pressure -resistant landing easy -break aviation fire extinguishing bag, it includes fire extinguishing bag body and the fire extinguishing agent packed in fire extinguishing bag body, it includes the hydrophobic layer at the intermediate place of fire extinguishing bag body and fire extinguishing agent and the through -hole on fire extinguishing bag body and hydrophobic layer.

[0015] Fire extinguishing bag body is three -edge packaging structure, three -edge seal is compared to back seal, because it is not needed like back seal additional need to adjust the back edge, so the processing complexity is lower, and the edge precision is higher.And in testing, it is found that the burst effect of back seal is not as good as three -edge seal, especially vertical drop, the diffusion effect of fire extinguishing gel is weak.And four -edge seal compared to three -edge seal needs more cutter head and more processing steps in processing, but the burst effect is similar, compared to the structure strength of three -edge seal is weakened, so after considering the production cost and production convenience, and burst effect and structure strength, select three -edge seal type edge sealing method.

[0016] Through -hole is vertically arranged on fire extinguishing bag body and hydrophobic layer, the through -hole section is trapezoidal, the one end of through -hole aperture is far away from fire extinguishing agent, can realize guaranteeing wetting gradient, reducing the loss of water under the premise, ensure water permeability.Setting the restriction of tapered through -hole can reduce the loss of water on the basis of the original fabric water permeability.Although a layer of PVDF can greatly reduce the water loss of fire extinguishing bag, but also reduces the water absorption rate of fire extinguishing bag, so change the fabric structure, punch on the fabric, can effectively guarantee the water absorption rate before, and the hole longitudinal section presents inverted trapezoidal, big mouth outward, small mouth inward, let the water permeability from inside to outside reduce again, the fiber nap on the hole surface can also absorb the water molecules from inside to outside, and does not prevent a large number of from outside to inside, auxiliary wetting gradient formation.

[0017] Fire extinguishing bag body edge sealing ratio is the ratio of edge sealing area and fire extinguishing bag single side area, namely:

[0018]

[0019] S 短 =L2×D

[0020] S 长 =L1×D

[0021] S 封 =2×S 短 +S 长

[0022] Wherein, S 封 It is edge sealing area, S 总 It is single side total area, S 短 It is short side edge sealing area, S 长L1 is the length of the long side, L2 is the length of the short side, and D is the width of the edge.

[0023] As a further preferred embodiment of the present application, the hydrophobic layer is a polyvinylidene fluoride film with a thickness of 70-80 um coated on the fire extinguishing bag body, and the polyvinylidene fluoride nanofiber film is a PVDF nanofiber film. The PVDF nanofiber film has good hydrophobicity and stable chemical properties. Due to the different geometric morphology and contact angle of the fire extinguishing bag body and the fabric at the microscopic level, the critical breakthrough pressure of each in different directions is different, and the difference in the critical breakthrough pressure promotes the one-way transport of liquid. In addition, the double-layer structure forms a wetting gradient in the thickness direction. The fabric is made of electrospun poly-lactic acid non-woven fabric. The fabric combined with the fire extinguishing bag body can reduce the loss of moisture, but also reduces the water permeability.

[0024] As a further preferred embodiment of the present application, the fire extinguishing bag body is sealed by ultrasonic sealing as the sealing method. Compared with heat sealing, the ultrasonic knife does not need to apply glue when sealing, and the application of glue will cause the water permeability of the bag body material to deteriorate, which deviates from the original requirement. In addition, under the same sealing width, the compression resistance of heat sealing is much lower than that of ultrasonic sealing, so heat sealing is not selected. Compared with ultrasonic sealing, sewing is too tight and cannot burst when falling, so sewing is not selected.

[0025] As a further preferred embodiment of the present application, the fire extinguishing agent is a water-based type fire extinguishing agent powder that has not been foamed.

[0026] As a further preferred embodiment of the present application, two knife edges are provided on the fire extinguishing bag body. According to test results, after having two knife edges, no matter how many knife edges are added, the compression strength of the sealing edge will not change, and the material strength of the fire extinguishing bag body will be used instead.

[0027] The sealing edge is the weakest position of the compression strength of the fire extinguishing bag, so the sealing edge determines the minimum compression strength of the fire extinguishing bag. The width of the sealing edge and the number of knife edges are the main factors affecting the compression strength of the sealing edge. The sealing edge width is equivalent to the ratio of the sealing area to the single surface area of the fire extinguishing bag. The ratio increases by about 4.57% for each additional knife edge. On this basis, the sealing edge can continue to widen, which can continue to improve the sealing strength.

[0028] As a further preferred embodiment of the present application, the water-based gel fire extinguishing agent is filled into the fire extinguishing bag body made of polylactic acid hot-rolled non-woven fabric, and the fire extinguishing bag body is packaged, dried and stored by means of ultrasonic edge sealing. When used, the fire extinguishing bag body is placed in a water tank, water is added, and the fire extinguishing bag body is used after swelling. The fire extinguishing bag can be thrown and used for fire extinguishing. In the technical solution, the fire extinguishing bag only needs to be unpacked and placed in a delivery cabin, and water is filled in the delivery cabin for use. The fire extinguishing bag can also be filled with water first and then placed in the delivery cabin. During this period, no large equipment is used, and the filling can be simply performed by manual operation, which is simple and convenient to operate.

[0029] As a further preferred embodiment of the present application, the edge sealing proportion of the fire extinguishing bag body is 11% to 15%.

[0030] Advantages: Compared with the prior art, the one-way water permeable pressure-resistant landing easy-to-break aviation fire extinguishing bag has the following advantages:

[0031] (1) Data obtained through multiple experiments prove that the fire extinguishing bag is more suitable for three-edge packaging and packaging, which ensures the strength of the fire extinguishing bag and prevents the leakage of the fire extinguishing agent;

[0032] (2) The bag body structure is optimized, and the loss of water in the fire extinguishing bag during falling is reduced;

[0033] (3) By adopting a special edge sealing proportion, the fire extinguishing bag can maintain sufficient pressure resistance at the edge sealing proportion, and can also burst when landing;

[0034] (4) The unswollen fire extinguishing bag is very small and does not occupy too much space, improving the space utilization rate during storage and transportation, and ensuring safety without explosion during storage and transportation;

[0035] (5) Compared with the fire extinguishing bomb, the technical solution does not have the risk of explosion during storage and transportation due to the absence of explosive properties;

[0036] (6) When used, the fire extinguishing bag is placed in a water tank, water is added, and the fire extinguishing bag is used after swelling, reducing the steps and time during preparation, and also eliminating the need for additional loading equipment. BRIEF DESCRIPTION OF DRAWINGS

[0037] Figure 1 It is a structural schematic view of the present application;

[0038] Figure 2 It is a top view of the present application;

[0039] Figure 3 It is a full sectional view of the present application;

[0040] Figure 4 It is a local enlarged view of the present application;

[0041] Figure 5 It is a schematic diagram for the number of knife edges;

[0042] Figure 6 It is a schematic diagram for the edge sealing ratio. DETAILED DESCRIPTION

[0043] The utility model will be further illustrated below in combination with the drawings and specific embodiments.

[0044] As Figure 1 , Figure 2 , Figure 3 And Figure 4 The utility model discloses a one-way water permeable pressure-resistant landing easy-to-break aviation fire extinguishing bag, it includes the fire extinguishing bag body 1 of three edge package structure, the fire extinguishing agent 2 covered in fire extinguishing bag body 1, the hydrophobic layer 3 formed by the polyvinylidene fluoride film coated on fire extinguishing bag body 1 and the through -hole 4 vertically arranged on fire extinguishing bag body 1 and hydrophobic layer 3.

[0045] EMBODIMENT

[0046] Knife edge number and edge sealing experiment of fire extinguishing bag

[0047] When the edge sealing ratio is between 11% and 15% and the number of knife edges is 2, it meets the requirements of being resistant to pressure and not easy to break in the static state, but forms a broken jetting state in the landing state. During testing, the number of knife edges needs to be determined first, and then the outward extension distance of the edge sealing is confirmed to determine the edge sealing ratio. The following is a summary of the test results:

[0048] The knife edge test selects fire extinguishing bags of the same size, only the number of knife edges is different, and four kinds of fire extinguishing bags with one knife edge, two knife edges, three knife edges and four knife edges are set respectively. Five of each kind of fire extinguishing bag are taken to ensure stable data. As Figure 5 The test results are shown in the schematic diagram.

[0049] From the results, it can be seen that after having two knife edges, no matter how many knife edges are added, the pressure resistance of the edge sealing will no longer change, and instead the strength of the bag body material will bear it.

[0050] Take two knife edges to continue testing, and inwardly retract the knife edge position based on the two knife edges to obtain more edge sealing width, that is, a larger edge sealing ratio. The experiment uses a fire extinguishing bag size of 180mm long x 85mm wide, and increases the edge sealing width of the fire extinguishing bag according to the edge sealing ratio of 5%, 7%, 9%, 11%, 13%, 15%, 17% and 19%. As Figure 6 From the results, it can be seen that there is a pressure resistance inflection point between the edge sealing ratio of 11% and 15%, and the pressure resistance yield decreases after this interval, so the edge sealing ratio is appropriate in the interval of 11% to 15%.

[0051] Fire extinguishing bag air drop burst experiment

[0052] 1. First, the fire extinguishing bag is brewed to the full state;

[0053] 2. The full fire extinguishing bag is placed in the load unmanned aerial vehicle air drop box;

[0054] 3. The load unmanned aerial vehicle takes off and rises to the specified height;

[0055] 4. When rising to the specified height, press the switch to open the air drop box hatch, and drop the fire extinguishing bag;

[0056] 5. After the fire extinguishing bag lands, place the measuring marker;

[0057] 6. The unmanned aerial vehicle is used to take pictures downward to record the position of the fire extinguishing bag.

[0058] The fire extinguishing bag is dropped at a height of 50m, 100m, 150m, 200m, 250m, 300m and 350m to confirm whether the fire extinguishing bag burst effect meets the standard. Through the drop test, it can be known that the design structure of the utility model can normally burst in the normal drop at the use height in the case of more pressure resistance, the burst state is normal, and there is no case that the fire extinguishing agent is not thrown.

[0059] The above embodiments are only for illustrating the technical concept and characteristics of the utility model, the purpose is to enable the person skilled in the art to understand the content of the utility model and to implement it, and it cannot limit the protection scope of the utility model. Any equivalent transformation or modification made according to the spirit and essence of the utility model should be covered within the protection scope of the utility model.

Claims

1. A one-way water-permeable pressure-resistant landing breakable aviation fire extinguishing bag, comprising a fire extinguishing bag body (1) and a fire extinguishing agent (2) packed in the fire extinguishing bag body (1), characterized in that: It includes a hydrophobic layer (3) between the fire extinguishing bag body (1) and the fire extinguishing agent (2), and a through hole (4) on the fire extinguishing bag body (1) and the hydrophobic layer (3); The fire extinguishing bag body (1) is a three-edge packaging structure, and the through hole (4) is vertically arranged on the fire extinguishing bag body (1) and the hydrophobic layer (3); The edge sealing ratio of the fire extinguishing bag body (1) is the ratio of the edge sealing area to the single side area of the fire extinguishing bag, that is: S 短 = L2 x D S 长 = L1 x D S 封 = 2 x S 短 + S 长 wherein S 封 is the edge area, S 总 is the total area of one side, S 短 is the short edge area, S 长 is the long edge area, L1 is the long edge length, L2 is the short edge length, and D is the edge width.

2. The one-way water permeable pressure-resistant landing breakable aviation fire extinguishing bag according to claim 1, characterized in that: The hydrophobic layer (3) is a polyvinylidene fluoride film with a thickness of 70um-80um coated on the fire extinguishing bag body (1).

3. The one-way water permeable pressure-resistant landing breakable aviation fire extinguishing bag according to claim 1, characterized in that: The cross section of the through hole (4) is trapezoidal.

4. The one-way water permeable pressure-resistant landing breakable aviation fire extinguishing bag according to claim 3, characterized in that: The end of the through hole (4) with a larger aperture is away from the fire extinguishing agent (2).

5. The one-way water permeable pressure-resistant landing breakable aviation fire extinguishing bag according to claim 4, characterized in that: The fire extinguishing agent (2) is a water-based type fire extinguishing agent powder that has not been foamed.

6. The one-way water permeable pressure-resistant crashworthy aviation fire bag according to claim 1, wherein: The fire extinguishing bag body (1) is sealed by ultrasonic sealing.

7. The one-way water permeable pressure-resistant landing breakable aviation fire extinguishing bag according to claim 1, characterized in that: The fire extinguishing bag body (1) is provided with two knife edges (11).

8. The one-way water permeable pressure-resistant crashworthy aviation fire bag according to claim 1, wherein: The water-based gel fire extinguishing agent (2) is filled into the fire extinguishing bag body (1) made of polylactic acid hot-rolled non-woven fabric, and the fire extinguishing bag body (1) is packaged, dried and stored by ultrasonic sealing. When used, the fire extinguishing bag body (1) is placed in a water tank, water is added, and after the fire extinguishing bag body (1) is foamed, it can be used for throwing and putting out fires.

9. The one-way water permeable pressure-resistant crashworthy aviation fire bag according to claim 1, wherein: The edge sealing ratio of the fire extinguishing bag body (1) is 11%-15%.

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