Explosion-proof electrical cabinet

Abstract

The invention relates to the technical field of electrical cabinet protection, in particular to an anti-explosion electrical cabinet which comprises a double-layer shell, a heat exchange system, a circulating system and an adjusting system. The double-layer shell is connected with the bottom cabinet; the heat exchange system is arranged in the double-layer shell; the circulating system is connected with the double-layer shell; the pressure regulating system is connected with the circulating system; the fine-grained silica sand is arranged on the outer layer of the electrical cabinet to carry out capillary diversion on water drops on the outer surface of the electrical cabinet, heat in the electrical cabinet is distributed to the position of the shell to exchange heat with the water drops, the water drops are evaporated and discharged, gas in the cabinet forms internal circulation, and the temperature at the position of an electrical component is reduced; if explosion occurs, the fine-grained silica sand in the shell is subjected to explosion suppression and prevents internal electric sparks from igniting external combustible gas; the problems that the outer surface of the electrical cabinet dews to cause corrosion of a shell, moisture permeates into the cabinet to cause electric leakage and explosion, the sealing performance is improved, and heat cannot be dissipated well when the electrical cabinet works underground in a coal mine are solved.

Description

Technical Field

[0001] The invention relates to the technical field of electrical cabinet protection, and in particular to an explosion-proof electrical cabinet. Background Art

[0002] When electrical equipment is used in flammable and explosive environments, certain measures need to be taken to prevent explosions to ensure safe use. Explosion-proof electrical cabinets are currently divided into flameproof, increased safety and positive pressure types. The flameproof type is mainly to prevent the arc or spark generated by the electrical equipment from penetrating the cabinet in the event of a fault, thereby preventing the explosion gas from leaking into the external environment. The increased safety type increases overload protection by improving the electrical structure, reducing the probability of dangerous sources such as sparks and overheating, thereby reducing the risk of explosion. The positive pressure type uses an air compressor to input inert gas in the electrical cabinet and continuously pressurize it, so that the air pressure inside the cabinet is higher than the external air pressure, thereby avoiding the risk of explosion.

[0003] When working underground in a coal mine, due to the high risk factor of underground work and the fact that the air underground is full of flammable gases, explosive gases and various dusts, it is very easy to cause explosions of electrical equipment, so explosion-proof electrical cabinets are necessary equipment for safe production; when electrical equipment generates sparks or arcs during operation, it will cause the equipment to explode. When the sparks and arcs are transmitted to the outside of the equipment and come into contact with the flammable gases and dust in the air, it may even cause coal mine explosions and mine collapses, thus posing a great threat to the personal safety of underground workers. In order to prevent flammable gases and dust from entering the electrical cabinet, positive pressure electrical cabinets are usually used to make the air pressure inside the cabinet higher than the external air pressure; however, underground coal mines are affected by groundwater and have high air humidity. In order to prevent the internal air pressure from being too high and facilitate the heat dissipation in the electrical cabinet, it is usually necessary to open exhaust channels and heat dissipation holes (when the air pressure in the cabinet is too high, exhaust is discharged to the outside and closed after returning to normal). At this time, external moisture will enter the electrical cabinet, causing circuit leakage, explosion and other phenomena. The existing technology has proposed a good solution to this problem, such as a positive pressure explosion-proof distribution cabinet with patent publication number CN118213874B. When the air pressure in the cavity is insufficient and needs to be inflated, a pumping device is used to evacuate the air, and an air intake component and a dehumidification filter device are set to dehumidify and filter the gas, thereby avoiding excessive humidity in the electrical box, which may cause rust on the shell, circuit leakage, and explosion.

[0004] Although the existing technology has solved the problems of shell corrosion, circuit leakage and explosion caused by excessive humidity in the electrical box, the following problems still exist: when the electrical cabinet is used underground, the air humidity in the coal mine is high and the circulation is poor. When not working, the outer surface temperature of the electrical cabinet is lower than the dew point temperature, which will cause condensation on the outer surface of the electrical cabinet. Although the electrical components can generate heat when working, they cannot quickly diffuse to the outer shell of the electrical cabinet. At this time, water droplets will still appear on the outer surface of the electrical cabinet. After the temperature of the electrical cabinet wall increases, the air temperature near the surface of the electrical cabinet will increase. This part of the air with increased temperature still retains water vapor, and it will produce water droplets when it comes into contact with the humid air around it whose temperature has not increased. At this time, the water droplets will adhere to the surface of the cabinet; on the one hand, the outer surface of the electrical cabinet The water droplets condensed on the side plus the underground coal dust and sulfur dioxide and other gases will accelerate the rust of the electrical cabinet surface, making the cabinet unable to effectively block the entry of high-humidity flammable gases from the outside. After the surface of the electrical cabinet is rusted, it cannot effectively withstand the explosion pressure inside the electrical cabinet when an explosion occurs, causing electric sparks and arcs inside the equipment to be transmitted to the outside and cause coal mine explosions. On the other hand, positive pressure electrical cabinets need to be equipped with heat dissipation holes to regulate the temperature inside the electrical cabinet. The water droplets condensed on the surface of the cabinet will penetrate into the electrical cabinet through the gaps and heat dissipation holes of the electrical cabinet after flowing, causing circuit short circuits, leakage and even explosions. If an electrical cabinet with good sealing effect is used, the heat dissipation effect of the electrical cabinet will be poor, which will easily lead to increased circuit load and failure, thereby causing explosions.

[0005] In view of the above situation, in order to overcome the above technical problems, the present invention designs an explosion-proof electrical cabinet. Summary of the invention

[0006] The present invention provides an explosion-proof electrical cabinet, which solves the problem that condensation on the outer surface of the electrical cabinet causes rust of the outer shell, moisture penetrates into the cabinet and causes leakage explosion when working underground in a coal mine, while improving the sealing performance cannot dissipate heat well. Fine-grained silica sand is arranged on the outer layer of the electrical cabinet to conduct capillary flow to water droplets on the outer surface of the electrical cabinet, and the heat in the electrical cabinet is distributed to the position of the outer shell to exchange heat with the water droplets, the water droplets are evaporated and discharged, and the gas in the cabinet forms an internal circulation, thereby reducing the temperature at the position of the electrical components; and after the temperature exceeds a limit value, the circuit will automatically be rapidly cooled and oxygen will be isolated to prevent fire and explosion. If an explosion occurs, the fine-grained silica sand in the outer shell will be flameproof and block internal electric sparks from igniting external combustible gases.

[0007] To achieve the above object, the present invention provides the following technical solutions:

[0008] An explosion-proof electrical cabinet comprises a base cabinet, a gas storage pipe and a positive pressure system, and also comprises a double-layer shell, a heat exchange system, a circulation system and a regulating system; the double-layer shell comprises an outer shell and an inner shell; the outer shell is connected to the base cabinet; the inner shell is connected to the outer shell; the heat exchange system is arranged in the double-layer shell; the circulation system is connected to the double-layer shell; the regulating system is connected to the circulation system; during normal working process, the circulation system drives the upper layer of hot gas in the inner shell to rise and flow into the outer shell, the gas entering the outer shell will move downward and enter the inner shell again from the bottom of the inner shell, the descending gas in the outer shell transfers heat to the heat exchange system, the heat exchange system absorbs water droplets condensed on the outer surface of the outer shell and evaporates them into water vapor and discharges them; after the temperature in the inner shell rises above a limit value, the regulating system slides to release carbon dioxide and evenly distributes the carbon dioxide into the inner shell under the action of the circulation system.

[0009] Preferably, the outer shell includes a fixed shell and a heat-conducting shell; the fixed shell is connected to the base cabinet; and the heat-conducting shell is connected to the fixed shell.

[0010] In the above scheme, the shell of the electrical cabinet is divided into multiple layers, thereby improving the sealing effect and explosion-proof capability of the electrical cabinet. Even if external moisture corrodes the outer shell or enters the outer shell, the inner shell can still protect the circuit, further improving the waterproof performance. The double-layer outer shell can also prevent the temperature difference between the inside and outside of the electrical cabinet from increasing sharply, leading to the condensation of water vapor.

[0011] Preferably, the heat exchange system includes a water absorbing layer, an air guiding layer, a partition plate and a water-isolating membrane; the water absorbing layer is arranged in a linear array around a fixed shell; the air guiding layer and the water absorbing layer are spaced apart; the partition plate is arranged between the water absorbing layer and the air guiding layer; and the water-isolating membrane is arranged between the heat conductive shell and the water absorbing layer.

[0012] In the above scheme, the water precipitated on the outer shell is absorbed by the water absorption layer, and the water generated outside is absorbed by the water absorption layer (because the surface of the electrical cabinet is usually maintained at about 60 degrees during operation, in order to maintain positive pressure, the internal gas circulation effect of the positive pressure electrical cabinet is poor. At this time, the temperature of the electrical cabinet may even reach 80 degrees, and water can evaporate at any temperature, and the temperature difference between the hot end and the cold end can reach 60 degrees. There are gases such as ammonia in the water droplets precipitated on the surface of the electrical cabinet in the coal mine, and its evaporation temperature will be further reduced). At this time, the water droplets can evaporate into gas under the action of increased temperature and flow to the outside of the electrical cabinet through the gas conducting layer, completing heat exchange and exchanging the heat in the cabinet.

[0013] Preferably, the water absorbing layer is filled with fine-grained silica sand; and the partition plate is a honeycomb structure.

[0014] In the above scheme, since the water absorption layer is filled with fine-grained silica sand, the fine-grained silica sand can perform a short-distance capillary effect, absorb the condensed water on the outer layer and conduct it to the position of the heat-conducting shell, so that the condensed water can absorb heat and vaporize into water vapor. Under the action of thermal expansion, the water vapor will flow to the outside of the shell, completing the heat exchange cycle, helping the heat generated by the electrical components to be dissipated, and the fine-grained silica sand filled in the outer layer of the electrical cabinet can produce a buffering effect during an explosion, withstand the explosion pressure and prevent the explosion fragments from flying, and the fine-grained silica sand can absorb water and isolate the instantaneous heat generated during the explosion, avoiding the instantaneous excessive heat generated by the explosion and causing the external combustible gas to be ignited; the partition plate can prevent the leakage of fine-grained silica sand while allowing water vapor and water to enter and exit.

[0015] Preferably, the circulation system includes an inner chamber, a circulation cavity, a hot air channel and a reflux channel; the inner chamber is arranged inside the inner shell; the circulation cavity is arranged between the outer shell and the inner shell; the hot air channel is connected between the upper end of the inner chamber and the circulation cavity; the reflux channel is connected between the circulation cavity and the bottom of the inner chamber.

[0016] In the above scheme, a circulating flow is formed between the inner chamber and the circulation chamber, and the fluidity of the internal gas is increased to form an internal circulation. Since the heat generated by the electrical components in the inner chamber will rise, the upper gas will flow out from the hot gas channel into the circulation chamber. The gas in the circulation chamber will contact the heat-conducting shell, thereby increasing the temperature of the thermal evaporation end of the heat exchange system and improving the heat exchange efficiency. The gas exchanged in the circulation chamber will re-enter the inner chamber from the lower reflux channel after the exchange and cooling, helping the inner chamber to cool down and avoiding the electrical components from overheating and causing circuit failure and explosion.

[0017] Preferably, a guide impeller is provided in the reflux channel; the guide impeller is an axial flow impeller; and the inner wall of the heat-conducting shell is a wave-shaped structure.

[0018] In the above scheme, the axial flow structure can be used to realize the exhaust structure at the position of the return channel, so that the gas in the hot gas channel and the inner chamber can flow out, thereby helping the gas to form a flow cycle; after entering the circulation cavity, the contact area between the hot gas and the heat-conducting shell is increased under the action of the wavy structure of the heat-conducting shell, thereby improving the heat dissipation efficiency.

[0019] Preferably, the regulating system comprises a heat absorption chamber, an expansion chamber, a limit slide bar, a limit spring and a sealing member; the heat absorption chamber is arranged below the guide impeller, liquid carbon dioxide is stored therein, and an air vent is opened on the outer ring of the heat absorption chamber; the expansion chamber is arranged above the heat absorption chamber, and expansion medium is stored in the expansion chamber; the limit slide bar is slidably installed in the expansion chamber; the limit spring is connected between the limit slide bar and the expansion chamber; and the sealing member is installed in the heat absorption chamber.

[0020] In the above scheme, the components in the inner chamber generate heat after work, which causes the temperature of the inner chamber to rise. When the temperature rises above the limit value, the volume of the expansion medium expands to push the limit slide rod, and the limit slide rod pushes the sealing part to open the heat absorption chamber. Since liquid carbon dioxide is stored in the heat absorption chamber, after the pressure is released, the liquid carbon dioxide will quickly vaporize into gaseous carbon dioxide and absorb heat. The suction effect of the guide impeller on the bottom will send the cooled gas around it into the inner chamber, helping the inner chamber to complete rapid cooling, and the carbon dioxide gas is quickly distributed in the inner chamber to prevent fire and explosion.

[0021] Preferably, the sealing component includes a pressure slide groove, a sealing block and a pressure spring; the pressure slide groove is opened on the heat absorption chamber; the sealing block is vertically slidably installed in the pressure slide groove; a release slope is provided at the upper end of the sealing block; the pressure spring is connected between the expansion chamber and the sealing block; and a stretching slope is provided at the top end of the limiting slide rod.

[0022] In the above scheme, since the sealing block is installed in the pressure slide groove in a vertical sliding manner, the pressure of the liquid carbon dioxide on the sealing block is horizontal at this time, which improves the sealing effect of the liquid carbon dioxide and prevents it from leaking. When the limit slide rod slides, the inclined surface will be squeezed and released by stretching the inclined surface, so that the sealing block can slide vertically, thereby releasing carbon dioxide.

[0023] Compared with the prior art, the present invention has the following beneficial effects:

[0024] 1. Compared with the existing positive pressure electrical cabinet, the present invention provides a water absorption layer and an air conducting layer in the outer shell, and the water absorption layer is filled with fine-grained silica sand. Since the particle size of the fine-grained silica sand is small, capillary action can be achieved to absorb the water droplets generated on the outer shell of the electrical cabinet, on the one hand, avoiding direct contact with the outer shell of the electrical cabinet to cause rust, and on the other hand, the absorbed water droplets can be used to exchange heat with the heat generated by the electronic components in the cabinet, so that the working temperature of the electrical cabinet is maintained within an appropriate range, reducing the possibility of explosion. After the heat exchange, the water droplets will evaporate into water vapor and be discharged, further avoiding moisture from invading the interior of the electrical cabinet, thereby reducing the occurrence of leakage. Since the filling material is fine-grained silica sand, it can also play a flameproof effect during an explosion to avoid the explosion fragments from flying and injuring people. At the same time, it can also isolate the heat generated at the moment of the explosion to avoid the heat generated by the explosion being too high instantly, resulting in the ignition of external combustible gases and causing coal mine explosions.

[0025] 2. The present invention sets an inner chamber and a circulation chamber, and uses a guide impeller to allow the high-temperature gas accumulated above the inner chamber to enter the circulation chamber. The guide impeller is an axial flow impeller and is located below the inner chamber. It can pump the gas in the circulation chamber into the inner chamber, so that the gas forms a circulation flow in the inner chamber and the circulation chamber, and the heat of the gas passing through the circulation chamber is transferred to the heat-conducting shell to complete the heat exchange work with the heat exchange system, so that the gas returning to the inner chamber is cooled, ensuring that the circuit operating temperature is at an appropriate temperature. At the same time, the gas forms a circulation flow to avoid local excessive temperature. The gas here is an inert gas, which can also protect the circuit, thereby reducing the possibility of explosion of the electrical cabinet.

[0026] 3. The present invention sets up a heat absorption chamber. When the temperature exceeds the limit value, the liquid carbon dioxide can be released under the action of the expansion medium, so that it vaporizes and absorbs a large amount of heat and cooperates with the guide impeller to quickly distribute the low-temperature carbon dioxide gas to the inner chamber to protect the circuit. At the same time, the vaporization of liquid carbon dioxide into gaseous carbon dioxide will rapidly increase the air pressure in the electrical cabinet, so that the positive pressure system can adjust the air pressure and cut off the circuit to sound an alarm to avoid explosion of the equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0028] Figure 1 It is the overall structure diagram of the present invention;

[0029] Figure 2 It is a cross-sectional view of the internal structure of the present invention;

[0030] Figure 3 It is a cross-sectional view of the heat exchange system after sand filling of the present invention;

[0031] Figure 4 for Figure 3 A magnified view of the structure at center;

[0032] Figure 5 It is a cross-sectional front view of the present invention;

[0033] Figure 6 for Figure 5 A magnified view of the structure at B in the middle;

[0034] Figure 7 for Figure 5 A magnified view of the structure at C in the middle;

[0035] Figure 8 It is the hot air flow diagram in the inner chamber and the circulation chamber;

[0036] In the figure: 1. base cabinet; 2. gas storage pipe; 3. positive pressure system; 4. double-layer shell; 41. outer shell; 411. fixed shell; 412. heat-conducting shell; 42. inner shell; 5. heat exchange system; 51. water absorption layer; 52. air guide layer; 53. partition plate; 54. water-proof membrane; 6. circulation system; 61. inner chamber; 62. circulation chamber; 63. hot gas channel; 64. reflux channel; 641. guide impeller; 7. adjustment system; 71. heat absorption chamber; 711. air vent; 72. expansion chamber; 73. limit slide rod; 731. stretching slope; 74. limit spring; 75. sealing part; 751. pressure slide groove; 752. sealing block; 7521. release slope; 753. pressure spring. DETAILED DESCRIPTION

[0037] In order to better understand the above technical solution, the above technical solution will be described in detail below in conjunction with the accompanying drawings and specific implementation methods.

[0038] See also Figures 1 to 8 The present invention provides an explosion-proof electrical cabinet, and the technical solution is as follows:

[0039] As a specific embodiment of the present invention, refer to Figure 1 and Figure 2 An explosion-proof electrical cabinet includes a base cabinet 1, a gas storage pipe 2 and a positive pressure system 3, and also includes a double-layer shell 4, a heat exchange system 5, a circulation system 6 and a regulating system 7; the double-layer shell 4 includes an outer shell 41 and an inner shell 42; the outer shell 41 is connected to the base cabinet 1; the inner shell 42 is connected to the bottom of the outer shell 41; the heat exchange system 5 is arranged in the double-layer shell 4; the circulation system 6 is connected to the double-layer shell 4; the regulating system 7 is connected to the circulation system 6; during normal operation, the circulation system 6 drives the inner shell 4 The hot gas in the upper layer of the outer shell 42 rises and flows into the outer shell 41. The gas entering the outer shell 41 will move downward and enter the inner shell 42 again from the bottom of the inner shell 42. The descending gas in the outer shell 41 transfers the heat to the heat exchange system 5. The heat exchange system 5 absorbs the water droplets condensed on the outer surface of the outer shell 41 and evaporates them into water vapor and discharges them. When the temperature in the inner shell 42 rises above the limit value (about 90 degrees Celsius), the regulating system 7 slides to release carbon dioxide and evenly distributes the carbon dioxide to the inner shell 42 under the action of the circulation system 6.

[0040] As a specific embodiment of the present invention, refer to Figure 3 and Figure 4The outer shell 41 includes a fixed shell 411 and a heat-conducting shell 412; the fixed shell 411 is connected to the bottom cabinet 1; the heat-conducting shell 412 is connected to the fixed shell 411. The shell of the electrical cabinet is divided into multiple layers, so that the sealing effect and explosion-proof capability of the electrical cabinet are improved. Even if the external moisture corrodes the outer shell 41 or enters the outer shell 41, the inner shell 42 can still protect the circuit, further improving the waterproof performance. In addition, the double-layer shell can prevent the rapid increase in the temperature difference between the inside and outside of the electrical cabinet, which leads to condensation on the surface of the electrical cabinet.

[0041] As a specific embodiment of the present invention, refer to Figure 4 The heat exchange system 5 includes a water absorbing layer 51, an air guiding layer 52, a partition plate 53 and a water-isolating membrane 54; the water absorbing layer 51 is arranged in a linear array around the fixed shell 411; the air guiding layer 52 is spaced apart from the water absorbing layer 51; the partition plate 53 is arranged between the water absorbing layer 51 and the air guiding layer 52; the water-isolating membrane 54 is arranged between the heat-conducting shell 412 and the water absorbing layer 51. The fixed shell 411 is made of a water-permeable and breathable material and is corrosion-resistant. The water precipitated on the fixed shell 411 is absorbed by the water-absorbing layer 51, and the water generated outside is absorbed by the water-absorbing layer 51 (because the surface of the electrical cabinet is usually maintained at around 60 degrees during operation, the internal gas circulation effect of the positive pressure electrical cabinet is poor in order to maintain positive pressure. At this time, the temperature of the electrical cabinet may even reach 80 degrees, and water can evaporate at any temperature; and the temperature difference between the hot end and the cold end can reach 60 degrees. When working underground in a coal mine, there are gases such as ammonia in the water droplets precipitated on the surface of the electrical cabinet, and its evaporation temperature will be further reduced). At this time, the water droplets can evaporate into gas under the action of the increased temperature and flow to the outside of the electrical cabinet through the gas conducting layer 52, completing the heat exchange and exchanging the heat in the cabinet.

[0042] As a specific embodiment of the present invention, refer to Figure 4, the water absorption layer 51 is filled with fine-grained silica sand; the partition plate 53 is a honeycomb structure. Since the water absorption layer 51 is filled with fine-grained silica sand, the fine-grained silica sand can perform a short-distance capillary effect, absorb the condensed water on the outer layer and conduct it to the position of the heat-conducting shell 412, so that the condensed water can absorb heat and vaporize into water vapor. Under the action of thermal expansion, the water vapor will flow outside the shell to complete the heat exchange cycle, helping the heat generated by the electrical components to be dissipated, and the fine-grained silica sand filled in the outer layer of the electrical cabinet can produce a buffering effect during an explosion, withstand the explosion pressure and prevent the explosion fragments from flying, and the fine-grained silica sand can absorb water and instantly generate heat during the explosion. The amount of heat generated by the explosion can be isolated to prevent the external combustible gas from being ignited due to the instantaneous high heat generated by the explosion; the partition plate 53 can prevent the leakage of fine-grained silica sand while allowing water vapor and water to enter and exit; although the fine-grained silica sand is not as good as the capillary effect of metal powder as a capillary material, it is more stable to use it as an explosion-proof material here. Metal powder can cause dust explosions, and because the heat-conducting shell is in direct contact with the hot gas, it can quickly absorb heat, thereby helping the water that flows from the fixed shell to the heat-conducting shell through the fine-grained silica sand to evaporate, and the water evaporates into gas and flows out from the gas-conducting layer 52 to complete the heat exchange.

[0043] As a specific embodiment of the present invention, refer to Figure 5 , Figure 6 , Figure 7 and Figure 8 The circulation system 6 includes an inner chamber 61, a circulation chamber 62, a hot air channel 63 and a reflux channel 64; the inner chamber 61 is arranged inside the inner shell 42; the circulation chamber 62 is arranged between the outer shell 41 and the inner shell 42; the hot air channel 63 is connected between the upper end of the inner chamber 61 and the circulation chamber 62; the reflux channel 64 is connected between the circulation chamber 62 and the bottom of the inner chamber 61. A circulating flow is formed between the inner chamber 61 and the circulation chamber 62, and the fluidity of the internal gas is increased to form an internal circulation. Since the heat generated by the electrical components in the inner chamber 61 will rise, the upper gas will flow out from the hot gas channel 63 into the circulation chamber 62. The gas in the circulation chamber 62 will contact the heat-conducting shell 412, thereby increasing the temperature of the thermal evaporation end of the heat exchange system 5 and improving the heat exchange efficiency. After the heat exchange gas in the circulation chamber 62 is cooled down through the exchange, it will re-enter the inner chamber 61 from the lower reflux channel 64, helping the inner chamber 61 to cool down and avoiding the electrical components from overheating and causing circuit failure and explosion.

[0044] As a specific embodiment of the present invention, refer to Figure 5 , Figure 6 and Figure 7, a guide impeller 641 is arranged in the return channel 64; the guide impeller 641 is an axial flow impeller; the inner wall of the heat-conducting shell 412 is a wavy structure. The axial flow structure can realize the exhaust structure at the position of the return channel 64, and the gas in the hot gas channel 63 and the inner chamber 61 can flow out, thereby helping the gas to form a flow cycle; after entering the circulation chamber 62, the contact area between the hot gas and the heat-conducting shell 412 is increased under the action of the wavy structure of the heat-conducting shell 412. The material of the wavy structure can use a material with high thermal conductivity, and take into account the explosion-proof performance, so as to quickly absorb the heat of the gas and help improve the heat dissipation efficiency.

[0045] As a specific embodiment of the present invention, refer to Figure 5 and Figure 7 The regulating system 7 includes a heat absorption chamber 71, an expansion chamber 72, a limit slide bar 73, a limit spring 74 and a sealing member 75; the heat absorption chamber 71 is arranged below the guide impeller 641, and liquid carbon dioxide is stored therein, and a vent hole 711 is opened on the outer ring of the heat absorption chamber 71; the expansion chamber 72 is arranged above the heat absorption chamber 71, and an expansion medium is stored in the expansion chamber 72; the limit slide bar 73 is slidably installed in the expansion chamber 72; the limit spring 74 is connected between the limit slide bar 73 and the expansion chamber 72; the sealing member 75 is installed in the heat absorption chamber 71. When the components in the inner chamber 61 work and generate heat, the temperature of the inner chamber 61 rises. When the temperature rises above the limit value (the allowable range here is about 90 degrees Celsius, that is, exceeding 90 degrees Celsius), the volume of the expansion medium expands to push the limit slide 73, and the limit slide 73 pushes the sealing part 75 to open the heat absorption chamber 71. Since liquid carbon dioxide is stored in the heat absorption chamber 71, after the pressure is released, the liquid carbon dioxide will quickly vaporize into gaseous carbon dioxide and absorb heat. The suction effect of the guide impeller 641 on the bottom will send the cooled gas around it into the inner chamber 61, helping the inner chamber 61 to complete rapid cooling, and the carbon dioxide gas is quickly distributed in the inner chamber 61 to prevent fire and explosion.

[0046] As a specific embodiment of the present invention, refer to Figure 5 and Figure 7The sealing member 75 includes a pressure groove 751, a sealing block 752 and a pressure spring 753; the pressure groove 751 is opened on the heat absorption chamber 71; the sealing block 752 is vertically slidably installed in the pressure groove 751; a release slope 7521 is provided at the upper end of the sealing block 752; the pressure spring 753 is connected between the expansion chamber 72 and the sealing block 752; and a stretching slope 731 is provided at the top of the limiting slide rod 73. Since the sealing block 752 is installed in the pressure slide groove 751 in a vertical sliding manner, the pressure of the liquid carbon dioxide on the sealing block 752 is horizontal at this time, which improves the sealing effect of the liquid carbon dioxide and prevents it from leaking. When the limit slide bar 73 slides, it will squeeze the release slope 7521 by stretching the slope 731, so that the sealing block 752 can slide vertically, thereby releasing the carbon dioxide; since the carbon dioxide changes from liquid to gas, the air pressure in the electrical cabinet will rise rapidly, at this time the positive pressure system 3 will automatically adjust the air pressure, open the exhaust channel or exhaust hole on the electrical cabinet to discharge the excess gas inside it, and automatically close it when the air pressure is slightly greater than the external air pressure; and the positive pressure system 3 will automatically cut off the circuit when adjusting the air pressure and sound an alarm, thereby improving safety performance; because when the heat is too high, the circuit may have failed. At this time, compared with using a temperature sensor to control the emission of carbon dioxide, using a mechanical mechanism is more reliable, thereby avoiding the inability to discharge carbon dioxide normally due to a circuit failure.

[0047] Working process: In order to prevent water droplets formed on the outer casing of the electrical cabinet and external moisture from invading the electrical cabinet and causing leakage, explosion and the like, when water droplets are generated on the surface of the electrical cabinet, the water absorption layer 51 absorbs the water precipitated on the outer casing 41, and exchanges heat with the gas heated up by the operation of the electronic components in the inner chamber 61, so that the circuit operating temperature is maintained within an appropriate range while the water droplets are evaporated into water vapor and discharged, thus preventing them from invading the interior of the electrical cabinet.

[0048] Specifically, in order to prevent water droplets from being present on the cabinet surface for a long time, which may cause the cabinet surface to rust and moisture to enter the cabinet, when water droplets are generated on the surface of the electrical cabinet, the fine silica sand in the water absorption layer 51 absorbs the water precipitated on the outer shell 41 and guides the water droplets to the side close to the heat-conducting shell 412 through capillary action.

[0049] In order to discharge the water droplets after being absorbed to avoid accumulation, and to dissipate the heat of the circuit in the electrical cabinet, after the guide impeller 641 is started, the hot gas in the upper part of the inner chamber 61 will flow out from the hot gas channel 63 into the circulation chamber 62, and the gas in the circulation chamber 62 will contact the heat-conducting shell 412, thereby increasing the temperature of the heat evaporation end of the heat exchange system 5, so that the water droplets guided by the water absorption layer 51 can quickly complete heat exchange with the gas. At this time, the water droplets will evaporate into water vapor and be discharged from the gas guide layer 52, and the gas exchanged in the circulation chamber 62 will re-enter the inner chamber 61 from the lower reflux channel 64 after exchange and cooling, helping the inner chamber 61 to cool down, and avoiding the excessive heat of the electrical components causing circuit failure and explosion;

[0050] When the temperature in the inner chamber 61 is abnormal and exceeds the allowable range, in order to protect the circuit from explosion, the expansion medium in the expansion chamber 72 expands and pushes the limit slide bar 73. The limit slide bar 73 squeezes the release slope 7521 by stretching the slope 731, so that the sealing block 752 slides vertically upward. At this time, the pressure on the liquid carbon dioxide in the heat absorption chamber 71 is released. At this time, the liquid carbon dioxide quickly vaporizes and absorbs a large amount of heat. At this time, the low-temperature gas will enter the inner chamber 61 from the reflux channel 64 under the suction action of the guide impeller 641, and is quickly distributed to the inner chamber 61 under the action of the guide impeller 641, so that the temperature of the inner chamber 61 drops rapidly and the circuit is double protected under the covering action of the inert gas to avoid explosion.

[0051] When an explosion occurs, in order to prevent explosion fragments from flying and injuring people, and to prevent the electric sparks and high temperature in the electrical cabinet from instantly igniting the external combustible gas and causing a coal mine explosion, during the explosion, the fine-grained silica sand in the water-absorbing layer 51 will act as an explosion-proof layer and prevent the explosion fragments from flying. At the same time, due to the high temperature resistance of the fine-grained silica sand itself and the water droplets absorbed therein, the heat can be isolated at the moment of the explosion, thereby preventing the heat generated by the explosion from being too high and causing the external combustible gas to be ignited.

[0052] The above shows and describes the basic principles, main features and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments, and the above embodiments and descriptions are only for explaining the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention may have various changes and improvements, which fall within the scope of the present invention to be protected, and the scope of the present invention to be protected is defined by the attached claims and their equivalents.

Claims

1. An explosion-proof electrical cabinet, comprising a base cabinet (1), a gas storage pipe (2) and a positive pressure system (3), characterized in that: The invention also comprises a double-layer shell (4), a heat exchange system (5), a circulation system (6) and a regulating system (7); the double-layer shell (4) comprises an outer shell (41) and an inner shell (42); the outer shell (41) is connected to the bottom cabinet (1); the inner shell (42) is connected to the bottom of the outer shell (41); the heat exchange system (5) is arranged in the double-layer shell (4); the circulation system (6) is connected to the double-layer shell (4); the regulating system (7) is connected to the circulation system (6); when the temperature in the inner shell (42) is lower than a limit value, the circulation system (6) drives the upper heat exchanger in the inner shell (42) to cool down. The gas rises and flows between the inner shell (42) and the heat exchange system (5) to form a "U"-shaped structure. The gas enters the "U"-shaped structure and contacts the heat exchange system (5), transfers heat to the heat exchange system (5) and moves downward. The heat exchange system (5) absorbs water droplets condensed on the outer surface of the outer shell (41) and evaporates them into water vapor for discharge. The gas reaching the bottom of the "U"-shaped structure flows back into the inner shell (42). When the temperature in the inner shell (42) rises above a limit value, the regulating system (7) slides to release carbon dioxide and evenly distributes the carbon dioxide into the inner shell (42) under the action of the circulation system (6).

2. An explosion-proof electrical cabinet according to claim 1, characterized in that: The outer shell (41) comprises a fixed shell (411) and a heat-conducting shell (412); the fixed shell (411) is connected to the base cabinet (1); and the heat-conducting shell (412) is connected to the fixed shell (411).

3. An explosion-proof electrical cabinet according to claim 2, characterized in that: The heat exchange system (5) comprises a water absorbing layer (51), an air guiding layer (52), a partition plate (53) and a water-isolating membrane (54); the water absorbing layer (51) is arranged in a linear array around a fixed shell (411); the air guiding layer (52) and the water absorbing layer (51) are arranged at intervals; the partition plate (53) is arranged between the water absorbing layer (51) and the air guiding layer (52); and the water-isolating membrane (54) is arranged between the heat-conducting shell (412) and the water absorbing layer (51).

4. An explosion-proof electrical cabinet according to claim 3, characterized in that: The water absorbing layer (51) is filled with fine-grained silica sand; and the partition plate (53) is a honeycomb structure.

5. The explosion-proof electrical cabinet according to claim 2, characterized in that: The circulation system (6) comprises an inner chamber (61), a circulation cavity (62), a hot air channel (63) and a return channel (64); the inner chamber (61) is arranged inside an inner shell (42); the circulation cavity (62) is arranged between an outer shell (41) and an inner shell (42); the hot air channel (63) is connected between the upper end of the inner chamber (61) and the circulation cavity (62); and the return channel (64) is connected between the circulation cavity (62) and the lower part of the inner chamber (61).

6. An explosion-proof electrical cabinet according to claim 5, characterized in that: A guide impeller (641) is arranged in the return channel (64); the guide impeller (641) is an axial flow impeller; and the inner wall of the heat-conducting housing (412) is a wave-shaped structure.

7. An explosion-proof electrical cabinet according to claim 6, characterized in that: The regulating system (7) comprises a heat absorption chamber (71), an expansion chamber (72), a limit slide bar (73), a limit spring (74) and a sealing member (75); the heat absorption chamber (71) is arranged below the guide impeller (641), liquid carbon dioxide is stored in the heat absorption chamber (71), and a vent hole (711) is provided on the outside of the heat absorption chamber (71); the expansion chamber (72) is arranged above the heat absorption chamber (71), and an expansion medium is stored in the expansion chamber (72); the limit slide bar (73) is slidably installed in the expansion chamber (72); the limit spring (74) is connected between the limit slide bar (73) and the expansion chamber (72); and the sealing member (75) is installed in the heat absorption chamber (71).

8. An explosion-proof electrical cabinet according to claim 7, characterized in that: The sealing member (75) comprises a pressure slide groove (751), a sealing block (752) and a pressure spring (753); the pressure slide groove (751) is provided on the heat absorption chamber (71); the sealing block (752) is vertically slidably installed in the pressure slide groove (751); a release inclined surface (7521) is provided at the upper end of the sealing block (752); the pressure spring (753) is connected between the expansion chamber (72) and the sealing block (752); and a stretching inclined surface (731) is provided at the top end of the limiting slide rod (73).

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