Intermittent spraying fire extinguishing device and method using aerosol boosting liquid fire extinguishing agent

Abstract

An intermittent spraying fire extinguishing device and method using an aerosol boosting liquid fire extinguishing agent, the fire extinguishing device comprising a shell (1) and an aerosol generating fire extinguishing agent (2) arranged in the shell (1). A front cover (3) is provided on the front side of the shell (1), and nozzles (4) are formed on a surface of the front cover (3). An end surface of the aerosol generating fire extinguishing agent (2) is connected to one end of an activation part (5). The shell (1) is internally provided with a piston (7) slidably fitted with the shell, and the piston (7) is connected to the bottom of the front cover (3) by means of a threaded rod (6.1) of a ball screw mechanism (6). The top of the threaded rod (6.1) is fixedly connected to the center of a rotatable cover (8). A liquid fire extinguishing agent (12) is provided between the piston (7) and the front cover (3). Spray holes (9) are formed on the surface of the rotatable cover (8). When the rotatable cover (8) rotates, the spray holes (9) and the nozzles (4) are periodically overlapped and staggered.

Description

An intermittent spraying fire extinguishing device and method for aerosol-assisted liquid fire extinguishing agent Technical Field

[0001] The present invention relates to the technical field of new energy battery fire extinguishing, and in particular to an intermittent spraying fire extinguishing device and method for aerosol-assisted liquid fire extinguishing agent. Background Art

[0002] When new energy batteries experience thermal runaway, they often continue to produce flammable gases. Traditional aerosol fire extinguishing devices are difficult to extinguish the flames instantly. Pulse fire extinguishing devices can extinguish the flames instantly but cannot achieve the effect of continuous suppression. When the pulse fire extinguishing device is used in combination with the traditional aerosol fire extinguishing device, the pulse fire extinguishing device can extinguish the flames generated instantly when the battery experiences thermal runaway, and the traditional aerosol fire extinguishing device can suppress the flames to a certain extent after the pulse fire extinguishing device is sprayed. Theoretically, the combination of the two overcomes each other's shortcomings, can extinguish the flames instantly and achieve the effect of continuous suppression; however, the following problems still exist. Taking the battery compartment where the battery is located as an example, when the battery experiences thermal runaway, a large amount of flammable gas escapes from the battery and enters the battery box At this time, after the fire extinguishing device is activated, due to the large gas production of the traditional aerosol fire extinguishing device, the aerosol fire extinguishing agent will quickly fill the entire battery box (that is, the battery compartment where the battery is located). In this process, only part of the flammable gas is pushed out of the battery compartment. More flammable gas is often pressed inside the battery and cannot be completely discharged due to the excessive positive pressure in the battery compartment when the aerosol fire extinguishing device is sprayed. Therefore, when the aerosol fire extinguishing device is completed, the pressure in the battery compartment drops, and a large amount of flammable gas escapes from the inside of the battery again, and there is still a risk of re-ignition; therefore, it is necessary to improve the traditional aerosol fire extinguishing device and design a fire extinguishing device that can spray continuously and intermittently, so that the pressure of the battery box increases and decreases periodically, thereby solving the above problems. Summary of the Invention

[0003] The purpose of the present invention is to overcome the above-mentioned shortcomings and provide an intermittent spraying fire extinguishing device and method for an aerosol-assisted liquid fire extinguishing agent, which can continuously perform an intermittent spraying process so that the pressure of the battery box increases and decreases periodically, which is conducive to the complete discharge of the combustible gas inside the battery in the battery box and prevents the risk of re-ignition.

[0004] In order to solve the above technical problems, the present invention adopts the following technical solution: an intermittent spraying fire extinguishing device for aerosol-assisted liquid fire extinguishing agent, comprising a shell and a gas-generating fire extinguishing agent arranged in the shell, a front cover is provided on the front side of the shell, a nozzle is opened on the surface of the front cover, the end face of the gas-generating fire extinguishing agent is connected to one end of the starting component, a piston is provided in the shell and is slidably matched with the piston, the piston is connected to the bottom of the front cover through a screw of a ball screw mechanism, the top of the screw is fixedly connected to the center of the rotating cover, liquid fire extinguishing agent is provided between the piston and the front cover, a nozzle is opened on the surface of the rotating cover, and when the rotating cover rotates, the nozzle and the nozzle periodically overlap and intersect.

[0005] Preferably, the ball screw mechanism includes a nut fixed inside the piston, the spiral groove area where the nut contacts the screw is filled with balls, and the top side of the screw is rotatably connected to the center of the front cover through a bearing.

[0006] Preferably, the rotating cover is located on the upper side or the lower side of the front cover.

[0007] Preferably, the gas-generating fire extinguishing agent is an aerosol generating agent, and the liquid fire extinguishing agent is a perfluorohexanone fire extinguishing agent.

[0008] Preferably, the gas-generating fire extinguishing agent is a columnar structure formed by pressing aerosol generating agent powder.

[0009] Preferably, the starting component is an electric ignition head or a thermal wire structure.

[0010] Preferably, the outer edge of the front cover is threadedly connected to the top of the shell, and the bottom of the shell is threadedly connected to the outer edge of the rear cover.

[0011] Preferably, the gas-generating fire extinguishing agent is located in the area where the back cover is located, and a silica gel layer is provided between the outer surface of the gas-generating fire extinguishing agent and the inner surface of the back cover.

[0012] Preferably, a guide rail is vertically provided on the inner side of the shell, and a guide groove is provided on the outer side of the piston, and the guide groove is slidably matched with the guide rail.

[0013] In addition, the present invention also discloses a fire extinguishing method of the intermittent spraying fire extinguishing device using the aerosol-assisted liquid fire extinguishing agent, which comprises the following steps:

[0014] S1: When thermal runaway occurs in the battery box, the starting component ignites the gas-generating fire extinguishing agent, which generates gas;

[0015] S2: The airflow pushes the piston to move to the position of the front cover, and the ball screw mechanism causes the screw to rotate;

[0016] S3: When the screw rotates, the rotating cover is driven to rotate, so that the spray holes on the surface of the rotating cover and the spray holes on the surface of the front cover periodically overlap and intersect;

[0017] S4: When the nozzle hole and the nozzle outlet coincide, the liquid fire extinguishing agent is ejected from the nozzle. Under the action of the high temperature inside the battery box, it is converted into gas to extinguish the fire inside the battery box. When the nozzle hole and the nozzle outlet intersect, the shell is sealed and the pressure is held back. Finally, the above process is repeated periodically to realize the intermittent spraying process, so that the pressure inside the battery box increases and decreases periodically.

[0018] S5: When the pressure inside the battery box increases, the combustible gas diluted by the fire extinguishing material is pressed out from the gaps in the battery box. When the pressure inside the battery box decreases, the combustible gas inside the battery escapes and enters the battery box, and the above process is repeated.

[0019] Beneficial effects of the present invention:

[0020] In the present invention, the airflow pushes the piston to move toward the position of the front cover, and the ball screw mechanism causes the screw to rotate. When the screw rotates, it drives the rotating cover to rotate, so that the spray holes on the surface of the rotating cover and the nozzles on the surface of the front cover periodically overlap and intersect, so that the liquid fire extinguishing agent can be continuously sprayed intermittently, so that the pressure of the battery box increases and decreases periodically, which is conducive to the complete discharge of combustible gases inside the batteries in the battery box and prevents the risk of re-ignition. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] FIG1 is a schematic diagram of the internal structure of an intermittent spraying fire extinguishing device that uses an aerosol to propel a liquid fire extinguishing agent;

[0022] FIG2 is a schematic diagram of the top structure of the front cover in FIG1 ;

[0023] FIG3 is a schematic diagram of the top view of the rotating cover in FIG1 ;

[0024] FIG4 is a schematic diagram of the planar structure of the piston and the inner wall of the housing. Implementation Method

[0025] The present invention will be described in further detail below with reference to the accompanying drawings and specific embodiments.

[0026] As shown in Figures 1 to 4, an intermittent spraying fire extinguishing device for aerosol-assisted liquid fire extinguishing agent includes a shell 1 and a gas-generating fire extinguishing agent 2 disposed in the shell 1. A front cover 3 is provided on the front side of the shell 1, and a nozzle 4 is provided on the surface of the front cover 3. The end face of the gas-generating fire extinguishing agent 2 is connected to one end of a starting component 5. A piston 7 is provided in the shell 1 and is slidably engaged with the piston 7. The piston 7 is connected to the bottom of the front cover 3 through a screw 6.1 of a ball screw mechanism 6. The top of the screw 6.1 is fixedly connected to the center of a rotating cover 8. Liquid fire extinguishing agent 12 is provided between the piston 7 and the front cover 3. A nozzle 9 is provided on the surface of the rotating cover 8. When the rotating cover 8 rotates, the nozzle 9 and the nozzle 4 periodically overlap and intersect.

[0027] Preferably, the ball screw mechanism 6 includes a nut 6.2 fixedly mounted inside the piston 7, the spiral groove area where the nut 6.2 contacts the screw 6.1 is filled with balls, and the top side of the screw 6.1 is rotatably connected to the center of the front cover 3 via a bearing. The ball screw mechanism 6 is a commonly used component in the field of continuous operation, and includes a nut 6.2, a screw 6.1, a ball return pipe, balls, a dust cover, a deflector, and other components. Since the balls roll along the spiral groove area formed by the screw and nut during operation, the movement resistance is extremely small. Therefore, when the piston 7 is pressed and moves upward, it drives the nut 6.2 upward, and the screw 6.1 rotates, thereby driving the rotating cover 8 to rotate. In addition, in the present invention, the bearing can effectively limit the screw 6.1, making its rotation process stable and reliable, while preventing the screw 6.1 from axial movement.

[0028] Preferably, the rotating cover 8 is located on the upper side or the lower side of the front cover 3 .

[0029] Preferably, the gas-generating fire extinguishing agent 2 is an aerosol generator, and the liquid fire extinguishing agent 12 is perfluorohexanone fire extinguishing agent. The aerosol generator generates a large amount of gas when burned, thereby driving the piston 7. Perfluorohexanone fire extinguishing agent, selected as the liquid fire extinguishing agent 12, has a boiling point of 49°C and readily vaporizes at high temperatures when a fire occurs, thereby changing the air pressure in the release area.

[0030] Preferably, the gas-generating fire extinguishing agent 2 is a columnar structure formed by pressing aerosol generating agent powder. The aerosol generating agent pressed into a columnar structure burns more slowly than the powdered aerosol generating agent, which can ensure the continuous release of the fire extinguishing agent.

[0031] The aerosol generator is a prior art, for example, the invention patent disclosed in Chinese Patent Publication No. CN101745195B is "An aging-resistant aerosol generator and its preparation process", which discloses that the aerosol generator is composed of an oxidant, a reducing agent, and a binder. The oxidant is potassium nitrate, the binder is phenolic resin, and the reducing agent is melamine. The mass percentages thereof are: potassium nitrate 74% to 80%, phenolic resin 8% to 15%, and the balance is melamine.

[0032] Its preparation method is:

[0033] Step 1: dissolving phenolic resin in ethanol to prepare a phenolic resin solution with a mass concentration of 40% to 55%;

[0034] Step 2: Grind the oxidizing agent and reducing agent to a fineness of 80-200 standard mesh, mix them according to the required proportion, and sieve them through 80-200 mesh three times to make them evenly mixed;

[0035] Step 3: Then add the phenolic resin solution to the mixed powder, stir for 10 minutes, and then use a 40-mesh screen to force granulate. Then dry the agent in an environment with a temperature of 40°C and a relative humidity of less than 20% until the volatile components are less than 1%;

[0036] Step 4: The dried medicine is pressed under a pressure of 10 MPa to form an aerosol generating agent column structure.

[0037] Preferably, the starting component 5 is an electric ignition head or a thermal wire structure. When the starting component 5 is an electric ignition head structure, it can be connected to a fire detection device, which is a temperature sensor and / or a smoke sensor. When a fire, overheating, or the like occurs, the fire detection device detects the high temperature environment generated in the battery compartment due to the fire and sends a signal to the microprocessor, which controls the starting component 5 to ignite the gas-generating fire extinguishing agent 2. When the starting component 5 is a thermal wire structure, the thermal wire structure can be directly ignited when a fire occurs, and then the thermal wire directly ignites the gas-generating fire extinguishing agent 2, without the need for additional fire detection devices and other external equipment, which is simpler and less costly.

[0038] Preferably, the outer edge of the front cover 3 is threadedly connected to the top of the housing 1, and the bottom of the housing 1 is threadedly connected to the outer edge of the rear cover 10. Through this threaded connection method, the convenience of installation of the entire fire extinguishing device can be improved and the production process is convenient.

[0039] Preferably, the gas-generating fire extinguishing agent 2 is located in the area where the back cover 10 is located, and a silicone layer 11 is provided between the outer surface of the gas-generating fire extinguishing agent 2 and the inner surface of the back cover 10. The silicone layer 11 can effectively isolate the heat generated by the combustion of the gas-generating fire extinguishing agent 2, preventing the surface temperature of the back cover 10 and the housing 1 from being too high.

[0040] Preferably, a guide rail 13 is vertically provided on the inner side of the housing 1, and a guide groove 14 is provided on the outer side of the piston 7, and the guide groove 14 slides with the guide rail 13. The sliding cooperation between the guide groove 14 and the guide rail 13 can ensure the stability of the movement of the piston 7 and prevent the piston 7 from rotating radially.

[0041] Preferably, a diaphragm is also attached to the nozzle 4 on the surface of the front cover 3, which can prevent moisture in the outside air from entering through the nozzle 4 during storage and transportation, causing the fire extinguishing agent to absorb moisture. At the same time, it is easy to rupture when under pressure, so it does not affect the spraying process of the fire extinguishing device.

[0042] During the actual production of the fire extinguishing device, a certain gap can be reserved between the rotating cover 8 and the front cover 3. If the rotation of the rotating cover 8 is obstructed or the pressure in the shell 1 suddenly increases, if the spray hole 9 and the nozzle 4 are in an intertwined state at this time, the airflow there will directly pass through the gap and the nozzle 4 into the outside to relieve pressure.

[0043] In order to ensure that the perfluorohexanone liquid fire extinguishing agent does not leak out of the gap in the contact area between the piston 7 and the screw 6.1 during the storage and transportation stage, a sealing ring can be added in the contact area between the lower end of the piston 7 and the screw 6.1 to effectively prevent the above-mentioned leakage.

[0044] In addition, the present invention also discloses a fire extinguishing method of the intermittent spraying fire extinguishing device using the aerosol-assisted liquid fire extinguishing agent, which comprises the following steps:

[0045] S1: When a battery in the battery box experiences thermal runaway, the starting component 5 ignites the gas-generating fire extinguishing agent 2, and the gas-generating fire extinguishing agent 2 generates gas;

[0046] S2: The airflow pushes the piston 7 to move to the position of the front cover 3, and the ball screw mechanism 6 causes the screw 6.1 to rotate.

[0047] S3: When the screw 6.1 rotates, it drives the rotating cover 8 to rotate, so that the spray holes 9 on the surface of the rotating cover 8 and the nozzles 4 on the surface of the front cover 3 periodically overlap and intersect;

[0048] S4: When the spray hole 9 and the nozzle 4 coincide with each other, the liquid fire extinguishing agent 12 is sprayed out from the nozzle 4, and is converted into gaseous state by the high temperature in the battery box to extinguish the fire in the battery box. When the spray hole 9 and the nozzle 4 are staggered, the shell 1 is sealed and a pressure-holding process is performed. Finally, the above process is repeated periodically to realize an intermittent spraying process, so that the pressure in the battery box increases and decreases periodically. In this step, when the fire extinguishing material is sprayed from the nozzle to extinguish the fire in the battery box, the gas inside the battery box increases, causing the pressure to increase. When the shell is sealed and a pressure-holding process is performed, the internal pressure of the battery box is released from the gap of the battery box itself, and the pressure decreases. Therefore, the pressure in the battery box increases and decreases periodically.

[0049] S5: When the pressure inside the battery compartment increases, the flammable gas diluted with the fire extinguishing agent is forced out through the gaps in the battery compartment. When the pressure inside the battery compartment decreases, the flammable gas inside the battery escapes and enters the battery compartment, repeating the above process. Through this reciprocating cycle of low and high pressure, the flammable gas generated in the battery can be diluted with the fire extinguishing agent and continuously discharged from the battery compartment, completing the entire fire extinguishing process and effectively preventing the risk of re-ignition.

[0050] The above embodiments are merely preferred technical solutions of the present invention and should not be construed as limiting the present invention. The embodiments and features in the embodiments of this application may be arbitrarily combined with each other unless they conflict. The scope of protection of the present invention shall be the technical solutions described in the claims, including equivalent alternatives to the technical features of the technical solutions described in the claims. Equivalent alternatives and improvements within this scope are also within the scope of protection of the present invention.

Claims

1. An intermittent spraying type fire extinguishing device for aerosol-assisted liquid fire extinguishing agent, comprising a housing (1) and a gas-generating fire extinguishing agent (2) arranged in the housing (1), a front cover (3) being arranged on the front side of the housing (1), a nozzle (4) being arranged on the surface of the front cover (3), an end face of the gas-generating fire extinguishing agent (2) being connected to one end of a starting component (5), characterized in that: A piston (7) is provided in the housing (1) and is slidably engaged with the housing (1). The piston (7) is connected to the bottom of the front cover (3) via a screw (6.1) of a ball screw mechanism (6). The top of the screw (6.1) is fixedly connected to the center of a rotating cover (8). A liquid fire extinguishing agent (12) is provided between the piston (7) and the front cover (3). A spray hole (9) is provided on the surface of the rotating cover (8). When the rotating cover (8) rotates, the spray hole (9) and the nozzle (4) periodically overlap and intersect.

2. The intermittent spraying fire extinguishing device of aerosol-assisted liquid fire extinguishing agent according to claim 1 is characterized in that: The ball screw mechanism (6) comprises a nut (6.2) fixed inside a piston (7), a spiral groove area where the nut (6.2) contacts the screw rod (6.1) is filled with balls, and the top side of the screw rod (6.1) is rotatably connected to the center of the front cover (3) via a bearing.

3. The intermittent spraying fire extinguishing device of aerosol-assisted liquid fire extinguishing agent according to claim 1 is characterized in that: The rotating cover (8) is located on the upper side or the lower side of the front cover (3).

4. The intermittent spraying fire extinguishing device of aerosol-assisted liquid fire extinguishing agent according to claim 1 is characterized in that: The gas-generating fire extinguishing agent (2) is an aerosol generating agent, and the liquid fire extinguishing agent (12) is a perfluorohexanone fire extinguishing agent.

5. The intermittent spraying fire extinguishing device of aerosol-assisted liquid fire extinguishing agent according to claim 4 is characterized in that: The gas-generating fire extinguishing agent (2) is a columnar structure formed by pressing aerosol generating agent powder.

6. The intermittent spraying fire extinguishing device of aerosol-assisted liquid fire extinguishing agent according to claim 1 is characterized in that: The starting component (5) is an electric ignition head or a thermal wire structure.

7. The intermittent spraying fire extinguishing device of aerosol-assisted liquid fire extinguishing agent according to claim 1 is characterized in that: The outer edge of the front cover (3) is threadedly connected to the top of the shell (1), and the bottom of the shell (1) is threadedly connected to the outer edge of the rear cover (10).

8. The intermittent spraying fire extinguishing device of aerosol-assisted liquid fire extinguishing agent according to claim 7, characterized in that: The gas-generating fire extinguishing agent (2) is located in the area where the rear cover (10) is located, and a silica gel layer (11) is provided between the outer surface of the gas-generating fire extinguishing agent (2) and the inner surface of the rear cover (10).

9. The intermittent spraying fire extinguishing device of aerosol-assisted liquid fire extinguishing agent according to claim 1, characterized in that: A guide rail (13) is also vertically provided on the inner side of the housing (1), and a guide groove (14) is provided on the outer side of the piston (7), wherein the guide groove (14) is slidably matched with the guide rail (13).

10. An intermittent spraying fire extinguishing device of aerosol-assisted liquid fire extinguishing agent according to any one of claims 1 to 9, characterized in that: It includes the following steps: S1: When a battery in the battery box experiences thermal runaway, the starting component (5) ignites the gas-generating fire extinguishing agent (2), and the gas-generating fire extinguishing agent (2) generates gas; S2: The airflow pushes the piston (7) to move toward the position of the front cover (3), and the ball screw mechanism (6) causes the screw (6.1) to rotate. S3: When the screw (6.1) rotates, the rotating cover (8) is driven to rotate, so that the spray holes (9) on the surface of the rotating cover (8) and the spray ports (4) on the surface of the front cover (3) are periodically overlapped and staggered; S4: When the spray hole (9) and the nozzle (4) overlap, the liquid fire extinguishing agent (12) is sprayed out from the nozzle (4) and, under the action of the high temperature in the battery box, is converted into a gaseous state to extinguish the fire in the battery box. When the spray hole (9) and the nozzle (4) intersect, the housing (1) is sealed and a pressure holding process is performed. Finally, the above process is repeated periodically to achieve an intermittent spraying process, so that the pressure in the battery box increases and decreases periodically. S5: When the pressure in the battery box increases, the combustible gas diluted by the fire extinguishing material is pressed out from the gaps in the battery box. When the pressure in the battery box decreases, the combustible gas inside the battery escapes and enters the battery box, and the above process is repeated in a cycle.

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