Automatic fire preventing and extinguishing device for coal mine goaf

Abstract

The invention relates to an automatic fire preventing and extinguishing device in a coal mine goaf. A jet orifice is provided with a ball valve, a starter is composed of a temperature sensing shell and a torsion spring piece, the temperature sensing shell is made of a material which deforms when heated, a groove is formed in the temperature sensing shell, the torsion spring piece is installed in the groove in a compression buckling mode, and the peripheral end of the torsion spring piece is fixed to the inner wall of the groove; a linkage assembly is further arranged, one end of the linkage assembly is connected with the circle center end of the torsion spring piece through a fixing clamp, and the other end of the linkage assembly is connected with the ball body through an energy storage shaft, so that the torsion spring piece rotates to drive the ball body to rotate. The temperature sensing part accurately senses the peripheral environment temperature, the starting part is more sensitive, the ball valve switch is good in sealing performance, the switch flow resistance is smaller, the coverage range is wider, and the cooling effect in an area is more obvious.

Description

Technical Field

[0001] The present invention belongs to the technical field of fire prevention and control of spontaneous combustion of coal residue in coal mine goaf areas, and specifically relates to an automatic fire prevention and extinguishing device for coal mine goaf areas. Background Art

[0002] The expansion of coal mine goaf area and the increase of coal residue are prone to cause spontaneous combustion of floating coal oxidation. To prevent spontaneous combustion of mines, the current prevention and control measures mainly include the injection of inert gas into closed areas, grouting fire extinguishing technology, gel fire extinguishing technology, etc., but there are still limitations on the timeliness and scope of fire extinguishing, and manual operation is required, which threatens life safety. In response to the problem of spontaneous combustion of coal residue in goaf, a Chinese invention patent with publication number CN202323022254 discloses a coal mine goaf fire prevention and extinguishing device, including a spherical tank body and a starter. When installing, remove the safety pin first. When the temperature of the goaf reaches the critical temperature of the temperature-sensitive glass rod, the high temperature and the preload spring cause the temperature-sensitive glass rod to break, and the moving block loses its restriction and ejects downward under the pressure of the preload spring. The stab of the moving block pierces the blocking cover, causing the fire extinguishing material in the inner shell to spray out under the action of the internal pressure. Disadvantages of this solution: 1. The tank body is a multi-layer structure, and the internal low-melting-point alloy material is not sensitive to external temperature changes; 2. The safety pin needs to be removed during installation, and there is a risk of accidentally triggering the device; 3. The fragments of the temperature-sensitive glass rod remain inside the device after being broken, and there is a risk of failure of the fire extinguishing process.

[0003] The Chinese invention patent with publication number CN217233577U discloses a spray mechanism for coal mine fire extinguishing, including a swing assembly and a spray assembly. When the first driving member can drive the spray end of the spray assembly to move with the motion group, the arc of the circular track can be more than 90 degrees and move upward to the vertical direction at most, so that the spray angle can cover the entire range of the circular track, thereby achieving accurate and rapid fire extinguishing. Disadvantages of this solution: 1. It needs to be transported close to the fire point, which takes a long time and affects the efficiency of fire extinguishing; 2. It needs to be transported manually, which has great safety hazards; 3. The goaf has different shapes and conditions, and the equipment cannot be transported in some areas, which has great limitations on fire extinguishing. Summary of the invention

[0004] The present invention aims to solve the above problems, thereby providing a goaf area automatic fire prevention and extinguishing device with a safer and more reliable starting mechanism.

[0005] In order to solve the above problems, the present invention adopts the following technical solution: An automatic fire prevention and extinguishing device for coal mine goaf areas includes a tank body, which is filled with fire extinguishing materials, a spray hole is provided on the tank body, a ball valve is connected above the spray hole, a release module is connected above the ball valve, and a starter is provided on the side of the ball valve, the ball valve is provided with a sphere inside, and a longitudinal through hole is provided at the center of the sphere, and when the through hole connects the spray hole and the release module, the fire extinguishing materials in the tank body can be released outward; the starter is composed of a temperature sensing shell and a torsion spring sheet, the temperature sensing shell is made of a material that deforms when heated, a groove is provided in the temperature sensing shell, the torsion spring sheet is compressed and buckled and installed in the groove, and its peripheral end is fixed to the inner wall of the groove; a linkage component is also provided, one end of which is connected to the center end of the torsion spring sheet through a fixing card, and the other end is connected to the ball through an energy storage shaft, so that the rotation of the torsion spring sheet drives the rotation of the ball.

[0006] Compared with the prior art, the present invention using the above technical solution has the following beneficial effects: The present invention automatically starts the tank fire extinguishing material to erupt, and has a simple and reliable structure; the temperature sensing component accurately senses the ambient temperature, the starting component is more sensitive, the ball valve switch has good sealing performance, the switch flow resistance is smaller, the coverage range is wider, and the cooling effect in the area is more obvious.

[0007] Preferably, a further technical solution of the present invention is: The ball valve includes a valve body, a ball, a valve seat and a valve stem, and the ball is installed in the valve cavity of the valve body; an upper threaded opening is provided on the upper part of the valve body, which is connected to the release module; a lower threaded opening is provided on the lower part of the valve body, which is connected to the injection hole; a valve seat is installed on the top of the lower threaded opening, and the upper edge of the valve seat abuts against the outer wall of the ball; a through hole is provided in the center of the ball; the valve stem passes through the side wall of the valve body, and its inner end is fixedly connected to the ball; the height of the valve cavity is equal to the height of the ball, and the width of the valve cavity is greater than the width of the ball.

[0008] The beneficial effects obtained by the above features are: the valve body has good sealing performance, the ball valve has good permeability, and the fire extinguishing material can be sprayed out fully and quickly.

[0009] The temperature sensing shell and the groove structure inside it are both circular, and the inner wall of the groove is evenly provided with teeth; the torsion spring sheet is an elastic metal sheet in the form of a coil, and a folded ring is provided at the peripheral end of the torsion spring sheet, and the folded ring is clamped in any one of the teeth.

[0010] The beneficial effects obtained by the above-mentioned features are as follows: the starting structure utilizes the tension of the torsion spring to drive the mechanical structure to release the material, the temperature sensing accuracy is higher, and it is not easy to be damaged before use.

[0011] The linkage assembly consists of large gear No. 1, large gear No. 2, small gear No. 1, small gear No. 2 energy storage shaft and a fixing card; large gear No. 1 is meshed with small gear No. 1, small gear No. 1 is coaxially fixed with large gear No. 2, and large gear No. 2 is meshed with small gear No. 2; the axis of large gear No. 1 is fixedly connected to the fixing card, the axis of small gear No. 2 is fixedly connected to the energy storage shaft, and the energy storage shaft is connected to the valve stem.

[0012] The beneficial effect obtained by the above-mentioned features is that the gear amplifies the force released by the torsion spring four times due to the double transmission ratio, so that it drives the energy storage shaft to rotate.

[0013] The fixing card is composed of a vertical shaft and at least one arc-shaped tube segment. The lower end of the vertical shaft is fixed at the center position of the large gear No. 1. The arc-shaped tube segment is concentrically arranged with the vertical shaft and a gap is provided between the vertical shaft, and a fitting opening is formed by the gap. The center end of the torsion spring sheet is provided with an arc bend, which embraces the outer wall of the vertical shaft and is clamped at the fitting opening.

[0014] The beneficial effects obtained by the above features are as follows: the energy storage shaft completely transmits the force to the ball valve stem without loss of force, so that the ball valve opening reaches 90° and the liquid carbon dioxide is completely released.

[0015] A protective shell is arranged on the outside of the ball valve on the tank body, the lower end of the protective shell is welded and fixed to the tank body shell, and a handle is arranged on the side of the protective shell.

[0016] The beneficial effects obtained by the above features are: protecting the ball valve and the starting device from damage and facilitating their removal.

[0017] A pin hole is arranged at the edge of the temperature sensing shell, a safety bolt is installed in the pin hole, and the inner end of the safety bolt is plugged into the outer wall of the protective shell.

[0018] Beneficial effects obtained from the above features: This solution avoids the starter from starting up accidentally. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a schematic diagram of the overall structure of the automatic fire prevention and extinguishing device of the present invention; Figure 2 This is an example diagram of the interior of the ball valve of the present invention; Figure 3 This is an example diagram of the gear set structure of the present invention; Figure 4 This is a schematic diagram of the temperature sensing module of the present invention; Figure 5 It is a schematic diagram of the thermal insulation material of the present invention; Figure 6 It is a schematic diagram of a release module of the present invention; Figure 7 This is the arrangement form of the present invention in the goaf area.

[0020] In the figure: 1. tank body; 2. fire extinguishing material; 3. insulation material; 4. tank shell; 41. inner shell; 42. outer shell; 5. injection hole; 61. valve body; 62. ball; 63. valve stem; 64. valve seat; 71. large gear No. 1; 72. large gear No. 2; 73. small gear No. 1; 74. small gear No. 2; 75. energy storage shaft; 76. fixing card; 81. temperature sensing shell; 82. torsion spring sheet; 83. arc bend; 84. folding circle; 85. tooth groove; 9. safety bolt; 10. release module; 11. handle. DETAILED DESCRIPTION

[0021] The present invention will be further described below in conjunction with embodiments, the purpose of which is only to provide a better understanding of the content of the present invention. Therefore, the examples given do not limit the protection scope of the present invention.

[0022] See also Figure 1-7 An automatic fire prevention and extinguishing device for coal mine goaf includes a tank body 1, which is filled with fire extinguishing material 2. The tank body 1 is provided with a spray hole 5, on which a ball valve 6 is installed, and a release module 10 is connected to the upper part of the ball valve 6. The ball valve 6 is equipped with a starter 8, which is used to rotate the ball valve 6 to spray out the fire extinguishing material 2. The release module 10 sprays the fire extinguishing material 360 degrees, thereby creating a low-temperature and low-oxygen environment within a certain range to prevent the residual coal from heating up and spontaneously combusting.

[0023] See also Figure 5 As an option, the tank shell 4 of the present invention is composed of an inner shell 41 and an outer shell 42, and a composite thermal insulation material 3 is arranged in the compartment between the two. The use of hard thermal insulation silicone as the outer shell material can not only withstand a certain weight and avoid damage to the tank body 1 caused by bumps during transportation, but also reduce the heat exchange between the inner shell and the outside world. The inner shell is made of composite multi-layer aerogel material, so that the high-pressure gas tank has a certain inflation capacity to ensure safety. The pressure in the tank is always controlled within the tolerance range of the tank body 1. The inner shell and the composite thermal insulation material 3 better reduce the exchange of internal and external heat, maintain low temperature during transportation, and avoid large fluctuations in the pressure in the tank body 1 caused by the influence of the external temperature.

[0024] The ball valve 6 has a ball 62 disposed inside, and a longitudinal through hole is disposed at the center of the ball 62. When the through hole is connected to the injection hole 5 and the release module 10, the fire extinguishing material 2 in the tank body 1 can be released outward.

[0025] See also Figure 2Specifically, the ball valve 6 includes a valve body 61, a ball 62, a valve seat 64 and a valve stem 63. The ball 62 is installed in the valve cavity of the valve body 61; the upper part of the valve body 61 is provided with an upper threaded opening, which is connected to the release module 10; the lower part of the valve body 61 is provided with a lower threaded opening, which is connected to the injection hole 5; the valve seat 64 is installed on the top of the lower threaded opening, and the upper edge of the valve seat 64 abuts against the outer wall of the ball 62; the center of the ball 62 is provided with a through hole; the valve stem 63 penetrates the side wall of the valve body 61, and its inner end is fixedly connected to the ball 62. The ball 62 is driven by the valve stem 63 to rotate the through hole, and when the through hole connects the upper threaded opening and the lower threaded opening, the fire extinguishing material 2 is sprayed out.

[0026] The height of the valve cavity is equal to the height of the sphere 62, and the width of the valve cavity is greater than the width of the sphere 62. There is a spiral groove on the valve stem 63, which cooperates with the guide pin of the valve stem 63 to control the left and right movement and up and down rotation of the sphere 62, but it cannot move up and down. The valve seat 64 is located in the channel of the valve body 61 and plays a sealing role. The sphere 62 is pressed tightly against the valve seat 64 by the mechanical pressure of the valve stem 63. When the energy storage shaft 75 rotates, the guide pin in the spiral groove of the valve stem 63 makes the sphere 62 move to the right and rotate, and the fire extinguishing material 2 flows from the middle. The side wall of the valve body 61 cooperates with the valve seat 64 to seal and prevent the fire extinguishing material 2 from leaking.

[0027] The starter 8 is composed of a temperature sensing housing 81 and a torsion spring sheet 82. The temperature sensing housing 81 is made of a material that deforms when heated. A groove is provided inside the temperature sensing housing 81. The torsion spring sheet 82 is installed in the groove in a compressed and bent manner, and its peripheral end is fixed to the inner wall of the groove.

[0028] For details, see Figure 4 The torsion spring piece 82 and the temperature sensing housing 81 are fixed in the following manner: the inner wall of the groove is evenly provided with tooth grooves 85 , and a folded ring 84 is provided at the peripheral end of the torsion spring piece 82 , and the folded ring 84 is fixed in any one of the tooth grooves 85 .

[0029] The temperature sensing housing 81 and the groove structure inside it are both circular, providing space for accommodating the pneumatic spring piece 83. The material of the temperature sensing housing 81 can be selected from materials that can expand or soften at around 70°C. The groove space becomes larger at high temperatures. When it is not enough to constrain the torsion spring piece 82, the preload force of the torsion spring piece is released. This solution uses special material metal as a detection structure for controlling the starter 8 to erupt, such as PA6 material. The PA6 temperature sensing housing will soften in an environment of 60°C to 70°C. After softening, the tooth groove 85 cannot maintain the constraint on the peripheral end of the lower torsion spring piece 82, and the torsion spring piece 82 can be relaxed. The physical property transformation of this material is reliable in application, ensuring that the fire extinguishing device can erupt reliably and the starting time is accurate. Of course, the material of the temperature sensing housing 81 is not limited to this one.

[0030] The torsion spring sheet 82 of this scheme is an elastic metal sheet in the form of a coil, and can be made of alloy spring steel or carbon spring steel. The torsion spring sheet 82 is compressed inward from the outer edge end, thereby tightening the expansion space of the spring, and the reaction force of the core end causes the inner ring of the spring to generate expansion pressure toward the outer ring. When the temperature sensing shell 81 is heated, the diameter of the groove becomes larger or the tooth groove becomes softer, which can achieve the effect of increasing the constraint space of the torsion spring sheet 82. The outer edge end is unconstrained and rotates counterclockwise. The outer ring of the spring releases the pressure on the inner ring, and the reaction force causes the center end to rotate clockwise. The rotation of the center end drives the large gear No. 1 71 to rotate, and then drives the valve stem to rotate. Reasonable control of the preload force of the torsion spring sheet 82 can control the ball valve to stop in an open state.

[0031] The inner ring of the temperature sensing housing 81 is used to limit the torsion spring sheet 82. Under normal temperature conditions, the torsion spring sheet 82 is installed in the temperature sensing housing 81 in a tightened state. When the temperature sensing housing 81 softens the tooth groove in a high temperature environment, the folded ring 84 of the torsion spring sheet 82 breaks through the constraint of the tooth groove 85, thereby causing expansion and rotation. The center end also rotates at the same time, and the rotation of the ball 62 is controlled by the linkage component 7.

[0032] A linkage assembly 7 is also provided, one end of which is connected to the center end of the torsion spring sheet 82 through a fixing card 76, and the other end is connected to the ball 62 through an energy storage shaft 75, so that the rotation of the torsion spring sheet 82 drives the ball 62 to rotate.

[0033] For details, see Figure 3 The linkage assembly 7 is composed of a large gear No. 1 71, a large gear No. 2 72, a small gear No. 1 73, a small gear No. 2 74, an energy storage shaft 75 and a fixing card 76; the large gear No. 1 71 is meshed with the small gear No. 1 73, the small gear No. 1 73 is coaxially fixed with the large gear No. 2 72, and the large gear No. 2 72 is meshed with the small gear No. 2 74; the large gear No. 1 71 is fixedly connected to the fixing card 76, the small gear No. 2 74 is fixedly connected to the energy storage shaft 75, and the energy storage shaft 75 is connected to the valve stem 63. The gear amplifies the force released by the torsion spring four times due to the double transmission ratio, so that it drives the energy storage shaft 75 to rotate.

[0034] The installation structure of the center end of the torsion spring piece 82: the fixing clamp 76 is composed of a vertical shaft and at least one arc-shaped tube segment, the lower end of the vertical shaft is fixed to the center position of the large gear No. 1 71, the arc-shaped tube segment is arranged concentrically with the vertical shaft and there is a gap between the vertical shaft, and the gap forms a fitting opening; the center end of the torsion spring piece 82 is provided with an arc-shaped bend 83, which is arc-shaped and fits on the outer wall of the vertical shaft and is fixed at the fitting opening. For details, see Figure 3 There are two arc-shaped segments, both of which are quarter-circular, and the sides of the arc-shaped segments are spaced apart by a quarter-circle. A quarter-circle arc bend 83 is set at the center end of the torsion spring sheet 82. The arc bend 83 is inserted between the arc-shaped segment and the vertical shaft, with one end extending out on the left and connected to the spring body on the left.

[0035] The energy storage shaft 75 is connected to the valve stem 63. The diameter of the energy storage shaft 75 is larger than that of the valve stem 63. The energy storage shaft 75 completely transmits the force to the valve stem 63 of the ball valve 6 without any force loss, so that the opening of the ball valve 6 reaches 90° and the liquid carbon dioxide is completely released.

[0036] Furthermore, a protective shell is provided on the outside of the ball valve 6 on the tank body 1, and the lower end of the protective shell is welded and fixed to the tank shell 4. For the tank body 1 with a large volume and weight, a handle 11 with low thermal conductivity is provided on one side of the protective shell. The handle 11 is arranged to be recessed inward, and the handle 11 is welded to the protective shell to ensure that it will not fall off, so as to facilitate transportation.

[0037] The protective shell can be used to form a chamber for installing the starter 8 and the transmission component. The PA6 temperature sensing shell 81 is fixed in the protective shell and fixed to the inner wall of the protective shell, making the temperature sensing shell 81 more stable and reinforcing the torsion spring sheet 82 to ensure that all the accumulated force of the torsion spring is used to start the switch of the ball valve 6.

[0038] Furthermore, the starter 8 is also provided with a safety bolt 9. Specifically, a pin hole is provided at the edge of the temperature sensing housing 81, and the safety bolt 9 is installed in the pin hole. The inner end of the safety bolt 9 is plugged into the outer wall of the protective shell. This prevents the unexpected rotation of the temperature sensing housing 81 from causing the spring to accidentally touch the ball valve 6. More specifically, the safety bolt 9 passes through the folded ring 84 of the torsion spring sheet 82. This safety bolt 9 is used to prevent the starter 8 from being accidentally started during transportation or storage.

[0039] Fire extinguishing material 2 is liquid carbon dioxide. Liquid carbon dioxide will quickly evaporate into gas, taking away part of the heat of the oxidized and heated coal, causing the fire source temperature in the area to drop. After the carbon dioxide content in the coal increases, it can resist oxidation and heating for a longer period of time.

[0040] See also Figure 6 The bottom of the release module 10 is sealed and connected to the surface of the tank body 1. The release module 10 is provided with a plurality of through holes, and the ejected material is uniformly ejected through the through holes to the surroundings, so that there are more ejection directions and the fire extinguishing material 2 can radiate a larger range. Furthermore, in order to make the fire extinguishing material eject more uniformly to the surroundings, the upper part of the tank body is also provided with a barrel-shaped cap covering the outside of the valve body, and the bottom of the barrel-shaped release device is sealed and connected to the surface of the protective shell by a concealed buckle or a thread.

[0041] Before the fire prevention and extinguishing device is buried in the predetermined position of the goaf, the safety pin 9 is removed first; when the temperature of the goaf continues to rise and reaches the critical temperature of the deformation of the temperature-sensitive shell 81, the high temperature causes the temperature-sensitive shell 81 to deform, and the torsion spring sheet 82 loses the restriction of the temperature-sensitive shell 81 and releases the elastic force, which drives the large gear No. 1 71 to rotate through the fixing card 76. The elastic force is amplified four times by the gear set, so that the energy storage shaft 75 drives the valve stem 63 to rotate, and the carbon dioxide in the tank body 1 loses the restriction of the ball valve 6 to release the pressure and is ejected under the action of pressure.

[0042] As an option, the injection hole 5 is arranged on the top of the tank body 1, and the filling hole of the one-way valve is arranged at the bottom of the tank body 1. The filling hole passes through the inner shell and the outer shell, so that the internal cavity of the inner shell is connected with the outside, which is convenient for injecting fire extinguishing materials. The fire extinguishing materials can be selected from liquid carbon dioxide nitrogen, ultrafine dry powder, etc., and liquid carbon dioxide is preferably used.

[0043] As an option, the inner shell of the tank body 1 is a high-pressure gas tank made of metal material, and the internal gas pressure changes to a certain extent under the influence of the external ambient temperature.

[0044] As an option, a safety valve connected to the inner cavity of the inner shell is provided on the tank body 1, so that the pressure inside the inner shell is automatically relieved when the pressure exceeds a certain value, thereby ensuring the safety of the device.

[0045] This automatic fire prevention and extinguishing device needs to be buried in a predetermined position in the goaf. As the temperature in the goaf continues to rise, the PA6 temperature sensing shell inside the automatic temperature sensing starting device is deformed, the torsion spring loses its constraint, and the stored force is released. The gear set is driven to rotate through the connected support rod, and the force released by the torsion spring is also increased. The ball valve 6 is driven to rotate through the energy storage shaft 75, and the inner hole of the ball valve 6 is aligned with the injection hole 5, and liquid carbon dioxide is ejected under the action of the internal pressure.

[0046] The process of the above-mentioned automatic fire prevention and extinguishing device for goaf area being arranged in the goaf area of ​​coal mine where the residual coal is heated and oxidized: A coal sample is collected on site in the goaf where the fire prevention and extinguishing device of the present invention is to be deployed, and the collected coal sample is subjected to a programmed temperature increase experiment to measure the critical temperature T of the coal spontaneous combustion of the coal sample. 1, and this temperature is determined as the starting temperature of the device; the linear expansion coefficient of PA6 is usually 1×10-4 / ℃, and the linear expansion formula is used: ΔL=α×L×ΔT, where ΔL is the change in length, α is the linear expansion coefficient, L is the original length, and ΔT is the change in temperature. It is concluded that ΔL is the distance from the deformation of the PA6 shell to the small ring leaving the groove. In the initial state, the PA6 shell is stuck with the torsion spring. When the PA6 shell is heated and deformed, the torsion spring releases the elastic force and amplifies the elastic force through the gear set, thereby twisting the ball valve in the support cylinder. At this time, the force of the energy storage shaft on the ball valve is called the "initial thrust". The type of spring and the material of the temperature-sensitive shell are selected according to the size of the device and the type of components to ensure that the initial thrust can support the rotation of the ball valve.

[0047] Step 2, burying the automatic fire protection and extinguishing device, including the following steps: 1) The volume of the fire extinguishing device of the present invention is 15kg, the injection rate is 0.05kg / s, and the injection pressure is 9 MPa. Once released, it is preliminarily estimated that the release is completed within about 300 seconds. However, as the liquid CO2 inside the fire extinguisher decreases, the pressure may gradually decrease, thereby affecting the injection rate. According to the void space n in the goaf, the range of action of the fire extinguishing device V=15 / n, Substituting V into the formula, we can get the CO of this fire extinguishing device: 2 Gasification influence radius. According to the different degrees of coal spontaneous combustion danger on the air inlet and return air sides of the goaf, the size of each fire prevention and extinguishing device and the spacing in the goaf are set using the specific influence radius obtained.

[0048] 2) In combination with the different degrees of coal spontaneous combustion danger on the air intake and return air intake sides of the goaf, the spacing between them is set according to the influence radius of the fire prevention and extinguishing devices obtained. The spacing between two adjacent fire prevention and extinguishing devices is l≤2r. Since in the actual mining process, the three spontaneous combustion zones of coal in the goaf move continuously with the advancement of the working face, and air leakage is prone to occur on the return air intake side of the goaf, the spacing of the fire prevention and extinguishing devices on the return air intake side of the goaf should be smaller than that on the air intake side of the goaf, and the spacing between the fire prevention and extinguishing devices gradually increases as they move away from the return air intake, and the automatic fire prevention and extinguishing devices in the goaf of the coal mine on the air intake side are buried deeper into the goaf; 3) To avoid the impact and damage of the rock collapse on the goaf roof to the fire prevention and extinguishing device, choose to bury it in the relatively stable stage of the collapsed rock mass after the working face is pressed periodically, and bury the fire prevention and extinguishing device in the goaf through the gap between the frames during the goaf frame shifting period. As the working face continues to move, the fire prevention and extinguishing device gradually enters the deep goaf. When the residual coal oxidizes and heats up in the surrounding area of ​​a certain fire prevention and extinguishing device, the heat will be transferred to the automatic temperature sensing start device. When the temperature rises to the set temperature T1, the PA6 shell deforms, the torsion spring releases the stored force, and the force increases under the action of the gear set. The energy storage shaft twists the ball valve to form a passage. At this time, the liquid carbon dioxide in the inner shell quickly vaporizes and releases a large amount of low-temperature carbon dioxide to the surrounding area through the through hole of the cap, thereby rapidly cooling the high-temperature coal body around the fire prevention and extinguishing device. At the same time, carbon dioxide can replace the surrounding oxygen to form an oxygen-free environment for a period of time, effectively preventing the residual coal from further oxidizing and heating up, and achieving the fire prevention and extinguishing effect in the goaf.

[0049] The above description is only a preferred feasible embodiment of the present invention, and does not limit the scope of rights of the present invention. All equivalent changes made using the contents of the present specification and its drawings are included in the scope of rights of the present invention.

Claims

1. An automatic fire prevention and extinguishing device for a coal mine goaf, comprising a tank body 1, the tank body (1) is filled with a fire extinguishing material (2), a spray hole (5) is provided on the tank body (1), a ball valve (6) is connected above the spray hole (5), a release module (10) is connected above the ball valve (6), a starter (8) is provided on the side of the ball valve (6), and the characteristics are: The ball valve (6) has a ball (62) disposed therein, and a longitudinal through hole is disposed at the center of the ball (62). When the through hole is connected to the injection hole (5) and the release module (10), the fire extinguishing material (2) in the tank body (1) can be released outwards; The starter (8) is composed of a temperature sensing housing (81) and a torsion spring sheet (82); the temperature sensing housing (81) is made of a material that deforms when heated; a groove is provided in the temperature sensing housing (81); the torsion spring sheet (82) is installed in the groove in a compressed and bent state, and its peripheral end is fixed to the inner wall of the groove; A linkage assembly (7) is also provided, one end of which is connected to the center end of the torsion spring sheet (82) via a fixing clamp (76), and the other end of which is connected to the ball (62) via an energy storage shaft (75), so that the rotation of the torsion spring sheet (82) drives the ball (62) to rotate.

2. The automatic fire prevention and extinguishing device for coal mine goaf according to claim 1 is characterized by: The ball valve (6) comprises a valve body (61), a sphere (62), a valve seat (64) and a valve stem (63), wherein the sphere (62) is installed in a valve cavity of the valve body (61); an upper threaded opening is provided at the upper portion of the valve body (61) and is connected to a release module (10); a lower threaded opening is provided at the lower portion of the valve body (61) and is connected to an injection hole (5); a valve seat (64) is installed at the top of the lower threaded opening, wherein the upper edge of the valve seat (64) abuts against an outer wall of the sphere (62); a through hole is provided at the center of the sphere (62); the valve stem (63) penetrates through a side wall of the valve body (61), and an inner end thereof is fixedly connected to the sphere (62); the height of the valve cavity is equal to the height of the sphere (62), and the width of the valve cavity is greater than the width of the sphere (62).

3. The automatic fire prevention and extinguishing device for coal mine goaf according to claim 1 is characterized by: The temperature sensing housing (81) and the groove structure inside the housing are both circular, and the inner wall of the groove is evenly provided with tooth grooves (85); the torsion spring sheet (82) is an elastic metal sheet in the form of a coil, and a folded ring (84) is provided at the peripheral end of the torsion spring sheet (82), and the folded ring (84) is fixed in any one of the tooth grooves (85).

4. The automatic fire prevention and extinguishing device for coal mine goaf according to claim 1 is characterized by: The linkage assembly (7) is composed of a large gear No. 1 (71), a large gear No. 2 (72), a small gear No. 1 (73), a small gear No. 2 (74), an energy storage shaft (75) and a fixing clamp (76); the large gear No. 1 (71) is meshed with the small gear No. 1 (73), the small gear No. 1 (73) is coaxially fixed with the large gear No. 2 (72), and the large gear No. 2 (72) is meshed with the small gear No. 2 (74); the axis of the large gear No. 1 (71) is fixedly connected to the fixing clamp (76), the axis of the small gear No. 2 (74) is fixedly connected to the energy storage shaft (75), and the energy storage shaft (75) is connected to the valve stem (63).

5. The automatic fire prevention and extinguishing device for coal mine goaf according to claim 1 is characterized by: The fixing clamp (76) is composed of a vertical shaft and at least one arc-shaped tube segment. The lower end of the vertical shaft is fixed at the center position of the large gear No. 1 (71). The arc-shaped tube segment is arranged concentrically with the vertical shaft and a gap is provided between the vertical shaft, and the gap forms a fitting opening. The center end of the torsion spring sheet (82) is provided with an arc-shaped bend (83), which is arc-engaged with the outer wall of the vertical shaft and is clamped at the fitting opening.

6. The automatic fire prevention and extinguishing device for coal mine goaf according to claim 1 is characterized by: A protective shell is also provided on the tank body (1) and outside the ball valve (6). The lower end of the protective shell is welded and fixed to the tank body shell (4), and a handle (11) is provided on the side of the protective shell.

7. The automatic fire prevention and extinguishing device for coal mine goaf according to claim 6 is characterized by: A pin hole is provided on the edge of the temperature sensing housing (81), a safety bolt (9) is installed in the pin hole, and the inner end of the safety bolt (9) is plugged into the outer wall of the protective housing.

8. The automatic fire prevention and extinguishing device for coal mine goaf according to claim 1 is characterized by: The temperature sensing housing (81) is made of PA6 material.

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