A compressed air foam injection device with built-in spiral foaming core and a micro fire fighting vehicle

Abstract

The application discloses a compressed air foam injection device with a built-in spiral foaming core and a micro fire fighting vehicle, and relates to the technical field of fire fighting equipment. The application comprises a foam storage tank, a drainage mixing pipeline, a spiral mixing sheet, a vortex mixing column and an air compression assembly. The air compression assembly comprises a driving cavity, a centrifugal driving disc, a rotating pipe shaft and an air compressor. After water supply by a fire hydrant, the water flows through the driving cavity to drive the centrifugal driving disc to rotate, and the air compressor is driven to work through the rotating pipe shaft, so that compressed air is delivered into the foam storage tank to form pressure, the foam agent is pushed into the drainage mixing pipeline, and the water flow is fully mixed under the action of the spiral mixing sheet and the vortex mixing column to form foam liquid and be sprayed out. The spraying capacity can be improved through a booster water pump, and the foam agent can be homogenized by cooperating with supporting partition ribs and a vehicle active hydraulic shock absorber.

Description

Technical Field

[0001] This invention relates to the field of fire-fighting equipment technology, specifically to a compressed air foam spraying device with a built-in spiral foaming core and a mini fire truck. Background Technology

[0002] Compressed air foam extinguishing technology mixes water, foaming agent, and compressed air to form a foam with strong coverage, isolating and cooling the fire source. In existing small firefighting equipment, to reduce overall vehicle size, foam storage, water supply, and air supply mechanisms are typically integrated into a limited space. However, existing structures usually rely on independent drive units for compressed air, reducing the utilization rate of the interior space of mini fire trucks. The additional drive system also increases energy consumption and maintenance costs. When fire hydrant water pressure is sufficient, existing systems cannot fully utilize the energy carried by the flowing water itself, resulting in low energy efficiency.

[0003] Secondly, the mixing process of foaming agent and water usually relies on simple pipeline mixing or single-stage disturbance structure. Due to the limited contact time between the two, local uneven concentration is prone to occur, resulting in unstable foam quality. During the spraying process, inconsistent foam density is likely to occur, affecting the fire extinguishing coverage effect.

[0004] Meanwhile, the foaming agent inside the foam storage tank is prone to local concentration differences after long-term storage. Traditional liquid storage structures lack active mixing mechanisms, which may cause changes in the concentration of foam sprayed before and after the start of fire extinguishing, affecting the consistency of foam quality. Summary of the Invention

[0005] To overcome the shortcomings of the prior art, the present invention provides the following technical solution: a compressed air foam injection device with a built-in spiral foaming core, comprising a foam storage tank and an air compressor assembly for providing pressure to the interior of the foam storage tank. A drainage mixing pipe is provided at the axial position of the foam storage tank, and both ends of the drainage mixing pipe extend through to the outside of the foam storage tank. A drain pipe and an air compressor assembly are respectively installed at both ends of the drainage mixing pipe. The air compressor assembly includes an air compressor for compressing air and a power module for providing power to the air compressor. The power module is connected in series between the drainage mixing pipe and the drain end of a booster pump. The inlet end of the booster pump is connected to a fire hydrant via a fire hose. A foam feeding pipe is vertically connected in the middle of the drainage mixing pipe. The end of the foam feeding pipe away from the drainage mixing pipe extends to the bottom of the inner wall of the foam storage tank (a gap is left between the end of the foam feeding pipe away from the drainage mixing pipe and the inner wall of the foam storage tank). A spiral mixing plate is provided on the inner wall of the drainage mixing pipe between the foam feeding pipe and the drain pipe. Multiple vortex mixing columns are fixedly installed in the radial direction of the spiral mixing plate itself. A gap is left between each adjacent vortex mixing column. The inner wall of the foam storage tank is also fixedly equipped with multiple supporting partition ribs along its own axis. Multiple grooves are evenly opened at the circumferential edge of the supporting partition ribs to facilitate the flow of liquid.

[0006] Preferably, the power module includes a drive chamber, and a rotary tube shaft is rotary sealed at the axial position of the drive chamber. Both ends of the rotary tube shaft extend to the outside of the drive chamber. One end of the rotary tube shaft is rotary sealed with a drainage mixing pipe through a rotary joint. The other end of the rotary tube shaft is fixedly sealed with a sealing plug. The sealing plug is fixed to the drive input shaft of the air compressor (a reduction gearbox is also connected between the two).

[0007] Preferably, the rotating tube shaft is provided with multiple water passage slots evenly distributed along its own axis at the position inside the drive cavity, and multiple centrifugal drive discs are arranged at equal intervals along its own axis inside the drive cavity. The gap between two adjacent centrifugal drive discs is connected to the inside of the rotating tube shaft through the water passage slots, and all centrifugal drive discs are fixed on the rotating tube shaft.

[0008] Preferably, a drive inlet is fixedly connected to the drive cavity in the tangential direction. The drive inlet is connected to the drain end of the booster pump through a transfer guide channel. The drive inlet is used to guide the water flow towards the centrifugal drive disk along the tangential direction of the centrifugal drive disk.

[0009] Preferably, the top and bottom of the foam storage tank are respectively equipped with a pressure boosting port and a feed inlet, wherein the exhaust port of the air compressor is connected to the pressure boosting port through a pressure guiding pipe, and a feed pipe is connected and installed at the feed inlet, wherein valves are installed in series in the middle of the feed pipe and the drain pipe.

[0010] A miniature fire truck for carrying a compressed air foam spraying device with a built-in spiral foaming core includes a fire box for accommodating a foam storage tank and an air compressor assembly. The foam storage tank is fixedly installed inside the fire box by support ribs. The air compressor and drive chamber in the air compressor assembly are fixedly installed inside the fire box by a hoisting bracket. A booster pump is fixedly installed on the inner wall of the fire box. A battery for powering the booster pump is also fixed on the inner wall of the fire box.

[0011] Preferably, a maintenance cover is also movably installed on the fire-fighting enclosure. The maintenance cover is fixedly and sealed on the side of the fire-fighting enclosure in a manner that facilitates disassembly. The water inlet, feed pipe, and drain pipe of the booster pump are all located on the outside of the fire-fighting enclosure and the maintenance cover. An air inlet window for supplying air to the air compressor is provided on the fire-fighting enclosure and / or the maintenance cover, and this air inlet window is equipped with an air filter.

[0012] Preferably, it also includes a mini fire truck for carrying the fire box, the mini fire truck having four wheel-side motors, each of which is equipped with an active hydraulic shock absorber and connected to the chassis support of the mini fire truck.

[0013] Compared with the prior art, the present invention has the following advantages: (1) The present invention utilizes the viscous action between the centrifugal drive disc inside the drive chamber and the water flow to generate rotation, and directly drives the air compressor through the rotating tube shaft, so that the energy carried by the fire hydrant water flow can be further utilized. The air compression process can be completed without setting up an independent high-power drive mechanism, thereby reducing the complexity of the overall structure, improving energy utilization efficiency, reducing the internal space occupation of the mini fire truck, and improving the equipment integration; (2) The present invention uses the internal pressure of the foam storage tank to push the foam agent into the drainage mixing pipe. Under the action of the spiral mixing plate, the foam agent and water generate rotational flow. At the same time, multiple vortex mixing columns further induce the formation of local vortices, so that the fluid generates disturbance in both the axial and radial directions, thereby increasing the contact path and mixing degree of the two, making the concentration of the foam liquid more uniform, and improving the efficiency of the system. (3) The foam storage tank of the present invention is equipped with supporting partition ribs and has flow grooves on its edge. The active hydraulic shock absorber controls the micro fire truck to generate periodic shaking, so that the foam agent flows and redistributes relative to the supporting partition ribs, promotes the self-circulation and mixing of the stored liquid, thereby reducing the local concentration difference caused by long-term storage, so that the foam liquid continuously output during the fire extinguishing process maintains a good concentration consistency and improves the fire extinguishing effect; (4) When the fire hydrant pressure can meet the requirements, the present invention can directly use water supply to complete the fire extinguishing; when the fire hydrant pressure is insufficient or the fire source is far away, the booster pump can be powered by the battery to assist in boosting the pressure, increase the fluid flow rate and spray distance, so that the equipment can adapt to the fire extinguishing needs under different water supply conditions, and enhance the use range and emergency response capability of the micro fire truck in complex environments. Attached Figure Description

[0014] Figure 1 This is a schematic diagram of the miniature fire truck of the present invention.

[0015] Figure 2 This is a schematic diagram of the internal structure of the fire-fighting box of the present invention.

[0016] Figure 3 This is a schematic diagram of the compressed air foam injection device of the present invention.

[0017] Figure 4 This is a diagram showing the connection method of the pressure guide tube in this invention.

[0018] Figure 5 This is a schematic diagram of the internal structure of the driving cavity of the present invention.

[0019] Figure 6 This is a schematic diagram of the internal structure of the foam storage tank of the present invention.

[0020] Figure 7 For the present invention Figure 6 Schematic diagram at point A in the middle.

[0021] Figure 8 This is a schematic diagram of the installation position of the spiral mixing plate of the present invention.

[0022] Figure 9 This is a schematic diagram of the spiral hybrid sheet structure of the present invention.

[0023] In the diagram: 101-Foam storage tank; 102-Pressure booster port; 103-Feed inlet; 104-Drainage mixing pipe; 105-Foam feeding pipe; 106-Supporting partition rib; 107-Feed pipe; 108-Drainage pipe; 201-Drive chamber; 202-Rotary joint; 203-Rotary pipe shaft; 204-Water passage groove; 205-Sealing plug; 206-Transfer guide channel; 207-Drive water inlet; 208-Centrifugal drive disc; 209-Booster water pump; 210-Air compressor; 211-Pressure guide pipe; 212-Battery; 213-Lifting bracket; 301-Spiral mixing plate; 302-Edge mixing column; 401-Fire truck housing; 402-Maintenance cover; 403-Supporting rib; 404-Mini fire truck. Detailed Implementation

[0024] The following is in conjunction with the appendix Figures 1-9 The technical solution of the present invention will be further illustrated through specific embodiments.

[0025] This invention provides a compressed air foam injection device with a built-in spiral foaming core, comprising a foam storage tank 101 and an air compressor assembly for supplying pressure to the interior of the foam storage tank 101. A drainage mixing pipe 104 is disposed at the axial position of the foam storage tank 101, with both ends of the drainage mixing pipe 104 extending to the outside of the foam storage tank 101. A drain pipe 108 and the air compressor assembly are respectively installed at both ends of the drainage mixing pipe 104. The air compressor assembly includes an air compressor 210 for compressing air and a power module for providing power to the air compressor 210. The power module is connected in series between the drainage mixing pipe 104 and the booster pump 209. Between the water ends, the inlet of the booster pump 209 is connected to the fire hydrant via a fire hose; a foam feeding pipe 105 is vertically connected to the middle of the drainage mixing pipe 104, with one end of the foam feeding pipe 105 away from the drainage mixing pipe 104 extending to the bottom of the inner wall of the foam storage tank 101 (a gap is left between the end of the foam feeding pipe 105 away from the drainage mixing pipe 104 and the inner wall of the foam storage tank 101); a spiral mixing plate 301 is provided on the inner wall of the drainage mixing pipe 104 between the foam feeding pipe 105 and the drain pipe 108, and multiple vortex mixing columns 302 are fixedly installed in the radial direction of the spiral mixing plate 301. A gap is left between each adjacent vortex mixing column 302. Multiple supporting partition ribs 106 are also fixedly provided on the inner wall of the foam storage tank 101 along its own axial direction, and multiple grooves are evenly opened on the circumferential edge of the supporting partition ribs 106 to facilitate the flow of liquid.

[0026] The power module includes a drive chamber 201. A rotary tube shaft 203 is rotatably and sealed at the axial position of the drive chamber 201. Both ends of the rotary tube shaft 203 extend to the outside of the drive chamber 201. One end of the rotary tube shaft 203 is rotary and sealed with a drainage mixing pipe 104 via a rotary joint 202. The other end of the rotary tube shaft 203 is fixedly sealed with a sealing plug 205, which is fixed to the drive input shaft of the air compressor 210 (a reduction gearbox is also connected between the two). Multiple water passage slots 204 are evenly distributed along the axial direction of the rotary tube shaft 203 inside the drive chamber 201. Multiple centrifugal drive discs 208 are evenly spaced along the axial direction inside the drive chamber 201. The gaps between adjacent centrifugal drive discs 208 communicate with the interior of the rotary tube shaft 203 through the water passage slots 204. All centrifugal drive discs 208 are fixed to the rotary tube shaft 203. A drive inlet 207 is fixedly connected to the drive chamber 201 along its tangential direction. The drive inlet 207 is connected to the drain end of the booster pump 209 through a transition guide channel 206. The drive inlet 207 is used to guide the water flow along the tangential direction of the centrifugal drive disc 208 toward the centrifugal drive disc 208. The top and bottom of the foam storage tank 101 are respectively equipped with a booster port 102 and a feed port 103. The exhaust port of the air compressor 210 is connected to the booster port 102 through a pressure guide pipe 211. A feed pipe 107 is connected and installed at the feed port 103. Valves are installed in series in the middle of the feed pipe 107 and the drain pipe 108.

[0027] A miniature fire truck for carrying a compressed air foam spraying device with a built-in spiral foam core includes a fire box 401 for accommodating a foam storage tank 101 and an air compressor assembly. The foam storage tank 101 is fixedly installed inside the fire box 401 by support ribs 403. The air compressor 210 and drive chamber 201 in the air compressor assembly are fixedly installed inside the fire box 401 by a lifting bracket 213. A booster pump 209 is fixedly installed on the inner wall of the fire box 401. A battery 212 for powering the booster pump 209 is also fixedly installed on the inner wall of the fire box 401. A maintenance cover 402 is also movably installed on the fire box 401. The maintenance cover 402 is fixedly and sealed on the side of the fire box 401 in a manner that facilitates disassembly. The water inlet, feed pipe 107, and drain pipe 108 of the booster pump 209 are all located on the outside of the fire box 401 and the maintenance cover 402. An air intake window for supplying air to the air compressor 210 is provided on the fire cabinet 401 and / or maintenance cover 402, and the air intake window is equipped with an air filter. The system also includes a mini fire truck 404 for supporting the fire cabinet 401. The mini fire truck 404 has four wheel-side motors, each equipped with an active hydraulic shock absorber connected to the chassis support of the mini fire truck 404.

[0028] Preparation process before use: Open the valve at the feed pipe 107, and then inject the foaming agent into the foam storage tank 101 (a bypass valve for venting is also provided at the top of the foam storage tank 101. The bypass valve is located near the pressure port 102. An electric valve is provided at the vent of the bypass valve. The electric valve opens or closes simultaneously with the valve at the feed pipe 107). After the foaming agent is injected, a gas phase space should be left at the top inside the foam storage tank 101. Then close the electric valve of the bypass valve and the valve at the feed pipe 107.

[0029] During the preparation phase before use, the active hydraulic shock absorbers at the four wheel-side motors of the mini fire truck 404 are used to induce a shaking motion (the active hydraulic shock absorbers alternately extend and retract during the preparation phase to achieve this shaking). This causes the foam agent inside the foam storage tank 101 to shake, resulting in displacement of the foam agent relative to the supporting partition ribs 106, which facilitates the mixing of the foam agent and makes it more uniform. The preparation process requires connecting the fire hydrant to the inlet of the booster pump 209 via the fire hose, and connecting the fire sprinkler to the drain pipe 108 via the fire hose. Then, the valve at the drain pipe 108 and the fire hydrant are opened, allowing the water in the fire hydrant to flow sequentially through the fire hose, booster pump 209, transfer guide channel 206, drive chamber 201, water passage groove 204, rotating pipe shaft 203, rotating joint 202, drainage mixing pipe 104, drain pipe 108, and fire sprinkler, finally spraying out. During this process, because there is a fire hose downstream of the foam feeding pipe 105, the pressure at the foam feeding pipe 105 is relatively high. At this time, a small amount of water will enter the foam feeding pipe 105. However, since the volume inside the foam storage tank 101 is constant, this water will not flow into the foam feeding pipe 105 continuously (a one-way valve is installed at the pressure guide pipe 211 or the pressure boosting port 102 to prevent liquid backflow).The water inside the drive chamber 201 enters tangentially along its inner wall through the drive inlet 207, causing the internal centrifugal drive discs 208 to rotate. This water flows into the rotating shaft 203 through the gaps between the centrifugal drive discs 208 and the water passages 204. The rotation of the centrifugal drive discs 208 is driven by the viscous force between the water and the surface of the discs. The reaction force of this viscous force is then applied to the water flow due to the rotation of the discs 208, causing the water in the gaps between the discs to rotate. This rotating water is subjected to centrifugal force, specifically a centrifugal force directed away from the rotating shaft 203, thus preventing the water from being centrifugally driven. The water flow in the gap of the centrifugal drive disk 208 is not linear, but rather bends due to centrifugal force. The degree of bending is affected by the rotational speed of the centrifugal drive disk 208. The higher the rotational speed of the centrifugal drive disk 208, the greater the centrifugal force on the water flow in the gap of the centrifugal drive disk 208. The greater the centrifugal force, the greater the curvature of the water flow bend, which in turn leads to a longer flow path in the gap of the centrifugal drive disk 208 (spiral trajectory flow, which has a longer flow path inside the drive cavity 201 compared to linear flow). The longer the interaction path between the water flow and the centrifugal drive disk 208, the greater the total contact area between the water flow and the centrifugal drive disk 208, the greater the fluid residence time, and the greater the boundary layer energy exchange time, which is beneficial. The water flow gradually transfers its kinetic energy to the centrifugal drive disc 208, improving the driving effect. The water flow then drives the centrifugal drive disc 208 to rotate faster until it reaches its rated maximum speed. The rotation of the centrifugal drive disc 208 drives the rotation of the rotary tube shaft 203. The rotation of the rotary tube shaft 203 drives the air compressor 210 (rotary compressor) through the sealing plug 205 and the reduction gearbox. The air compressor 210 compresses the air and then sends it into the gas phase space at the bottom of the foam storage tank 101 through the pressure guide pipe 211. This increases the pressure inside the foam storage tank 101, thereby pushing the foaming agent inside the foam storage tank 101 into the drainage mixing pipe 104 through the foam feeding pipe 105 (foam feeding pipe 105). The diameter of pipe 05 is predetermined according to the foaming agent ratio, allowing the foaming agent to flow into the drainage mixing pipe 104 and meet the water flow therein. Then, the water and foaming agent will flow to the spiral mixing plate 301. The spiral mixing plate 301 drives the water and foaming agent to rotate, thereby accelerating the mixing of foaming agent and water. A vortex mixing column 302 is also provided between the spiral mixing plates 301. When the water and foaming agent are rotated by the spiral mixing plate 301, they will also flow through the vortex mixing column 302. This part of the liquid will be affected by the vortex mixing column 302 to generate vortices. The vortex will further increase the mixing of foaming agent and water, so that the two are fully mixed. The mixed foam liquid will be discharged through the drain pipe 108 and finally covered to the fire source location by the fire sprinkler.

[0030] The booster pump 209 can also be started. The booster pump 209 is powered by the battery 212 to increase the water flow rate. It is suitable for situations where the water pressure of the fire hydrant is insufficient or the fire source is far away.

Claims

1. A compressed air foam injection device with a built-in spiral foaming core, characterized in that: Includes a foam storage tank (101) and an air compressor assembly for supplying pressure to the interior of the foam storage tank (101). A drainage mixing pipe (104) is provided at the axial position of the foam storage tank (101). Both ends of the drainage mixing pipe (104) extend through to the outside of the foam storage tank (101). A drain pipe (108) and an air compressor assembly are respectively installed at both ends of the drainage mixing pipe (104). The air compressor assembly includes an air compressor (210) for compressing air and a power module for powering the air compressor (210). The power module is connected in series between the drainage mixing pipe (104) and the drain end of the booster pump (209), wherein the inlet end of the booster pump (209) is connected to the fire hydrant via a fire hose. A foam feeding pipe (105) is vertically connected to the middle of the drainage mixing pipe (104). The end of the foam feeding pipe (105) away from the drainage mixing pipe (104) extends to the bottom of the inner wall of the foam storage tank (101). A spiral mixing plate (301) is provided on the inner wall of the drainage mixing pipe (104) between the foam feeding pipe (105) and the drain pipe (108). Multiple vortex mixing columns (302) are fixedly installed in the radial direction of the spiral mixing plate (301).

2. The compressed air foam injection device with a built-in spiral foaming core according to claim 1, characterized in that: The power module includes a drive chamber (201), and a rotary tube shaft (203) is rotary sealed at the axial position of the drive chamber (201). Both ends of the rotary tube shaft (203) extend to the outside of the drive chamber (201). One end of the rotary tube shaft (203) is rotary sealed with the drainage mixing pipe (104) through a rotary joint (202). The other end of the rotary tube shaft (203) is fixedly sealed with a sealing plug (205). The sealing plug (205) is fixed to the drive input shaft of the air compressor (210).

3. The compressed air foam injection device with a built-in spiral foaming core according to claim 2, characterized in that: The rotating tube shaft (203) is located inside the drive cavity (201) and has multiple water passage slots (204) evenly opened along its own axis. The drive cavity (201) is equipped with multiple centrifugal drive discs (208) with equal gaps along its own axis. The gap between two adjacent centrifugal drive discs (208) is connected to the inside of the rotating tube shaft (203) through the water passage slots (204). All centrifugal drive discs (208) are fixed on the rotating tube shaft (203).

4. The compressed air foam injection device with a built-in spiral foaming core according to claim 3, characterized in that: The drive chamber (201) is also fixedly connected to the drive inlet (207) in the tangential direction. The drive inlet (207) is connected to the drain end of the booster pump (209) through the transition guide channel (206). The drive inlet (207) is used to guide the water flow along the tangential direction of the centrifugal drive disk (208) toward the centrifugal drive disk (208).

5. A compressed air foam injection device with a built-in spiral foaming core according to claim 4, characterized in that: The top and bottom of the foam storage tank (101) are respectively equipped with a pressure boosting port (102) and a feed inlet (103). The exhaust port of the air compressor (210) is connected to the pressure boosting port (102) through a pressure guide pipe (211). A feed pipe (107) is connected to the feed inlet (103). Valves are installed in series in the middle of the feed pipe (107) and the drain pipe (108).

6. A miniature fire truck for carrying a compressed air foam injection device with a built-in spiral foaming core as described in any one of claims 1-5, characterized in that: The fire cabinet (401) includes a foam storage tank (101) and an air compressor assembly. The foam storage tank (101) is fixedly installed inside the fire cabinet (401) by a support rib (403). The air compressor (210) and drive chamber (201) in the air compressor assembly are fixedly installed inside the fire cabinet (401) by a hoisting bracket (213). A booster pump (209) is fixedly installed on the inner wall of the fire cabinet (401). A battery (212) for powering the booster pump (209) is also fixed on the inner wall of the fire cabinet (401).

7. A mini fire truck according to claim 6, characterized in that: A maintenance cover (402) is also movably installed on the fire box (401). The maintenance cover (402) is fixedly and sealed on the side of the fire box (401) in a way that facilitates disassembly. The water inlet end of the booster pump (209), the feed pipe (107) and the drain pipe (108) are all located on the outside of the fire box (401) and the maintenance cover (402).

8. A mini fire truck according to claim 7, characterized in that: It also includes a mini fire truck (404) for carrying the fire box (401), the mini fire truck (404) having four wheel-side motors, each equipped with an active hydraulic shock absorber connected to the chassis support of the mini fire truck (404).

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