Metal gate arc extinguishing device

Abstract

The invention discloses a metal gate arc extinguishing device, which comprises a shell assembly, an arc extinguishing gate assembly, a diversion assembly and an electromagnetic driving piece, and is characterized in that the shell assembly is provided with an insulating shell for limiting an arc extinguishing cavity; the arc-extinguishing gate assembly is coaxially arranged in the arc-extinguishing cavity, the arc-extinguishing gate assembly comprises a plurality of annular gate arc-extinguishing sheets which are stacked along the axial direction, and the inner diameters of the adjacent annular gate arc-extinguishing sheets are variably distributed; the flow guide assembly comprises a fixed flow guide body and a movable flow guide body which are axially and oppositely arranged, and the fixed flow guide body is arranged in the arc chute assembly and is close to the top of the arc chute assembly; the electromagnetic driving part is coupled to the movable flow guide body, and when forward excitation current is applied, a first electromagnetic field can be generated to enable the movable flow guide body to generate axial displacement towards the fixed flow guide body, so that electric conduction connection is formed; and when a reverse excitation current is applied, a reverse electromagnetic field is generated to drive the movable flow guide body to generate backward displacement, so that contact and separation are realized. According to the metal gate arc extinguishing device, arc extinguishing can be effectively carried out in a shorter time.

Description

Technical Field

[0001] The present invention relates to the technical field of new energy charging piles, and particularly relates to a metal grid arc extinguishing device. Background Art

[0002] In recent years, the new energy vehicle market has shown a rapid growth trend. Technological progress and policy support have promoted this development. As the "energy refueling station" for new energy vehicles, the construction and development of charging piles are of inestimable value for promoting the popularization and application of new energy vehicles. With the increase in the number of new energy vehicles, the demand for charging infrastructure is also continuously increasing. Therefore, accelerating the construction and layout of charging piles is of great significance for meeting market demand and promoting the development of the new energy vehicle industry. Arc extinguishing technology is an important part of the safety of charging piles. During the charging process, due to the sudden and rapid change of current, an arc is generated, which not only damages the charging pile itself but also may cause safety accidents such as fires.

[0003] Therefore, it is crucial to adopt advanced arc extinguishing technology to prevent this situation. Traditional spring arc extinguishing mainly relies on the mechanical force of the spring to quickly break and extinguish the arc relying on the metal grid. However, its performance is restricted by various factors:

[0004] 1. In terms of the current change rate, when the charging pile needs to quickly switch the charging power, such as from slow charging to fast charging mode, the current change rate increases significantly. At this time, due to the mechanical structure requiring a certain elastic response time, it is easy to cause ineffective arc extinguishing in a timely manner, thereby damaging electrical components.

[0005] 2. The working conditions have a significant impact on the spring arc extinguishing performance. In a vibrating environment, such as a charging pile in a highway service area, which is frequently affected by the vibration of passing vehicles, the spring is prone to displacement and deformation, and its mechanical properties are unstable, unable to accurately perform the arc extinguishing action, resulting in a significant reduction in the arc extinguishing effect. In areas with high humidity, such as during the rainy season in the south, the moisture in the air will adhere to the surface of the arc extinguishing device, reducing the insulation performance and increasing the probability of arc reignition; in a corrosive environment, such as a charging pile by the sea affected by sea breeze erosion, the spring and related metal components are prone to rust and corrosion, and the mechanical strength decreases, also weakening the arc extinguishing ability.

[0006] 3. Temperature change is also a major challenge. In the low-temperature environment in winter in the north, the internal temperature of the charging pile can drop to more than ten degrees Celsius below zero, the elastic modulus of the spring material changes, becomes brittle and hard, and the tensile performance deteriorates; in summer at high temperatures, the temperature of the arc extinguishing device rises after long-term operation, the spring is heated and relaxed, and the elastic force weakens, both of which cannot ensure stable and reliable arc extinguishing effect, posing a hidden danger to the safe operation of the charging pile. Summary of the Invention

[0007] In view of the deficiencies of the prior art, the technical problem to be solved by the present invention is to provide a metal grid arc extinguishing device that can effectively extinguish the arc in a shorter time.

[0008] To achieve the above object, the present invention is realized by the following technical solutions: A metal grid arc extinguishing device, comprising:

[0009] A housing assembly having an insulating housing that defines an arc extinguishing chamber;

[0010] An arc extinguishing grid assembly coaxially disposed in the arc extinguishing chamber, the arc extinguishing grid assembly comprising a plurality of annular grid arc extinguishing sheets stacked along the axial direction;

[0011] A diversion assembly including a fixed current guide and a moving current guide axially opposed to each other, the fixed current guide being disposed in the arc extinguishing grid assembly and close to the top of the arc extinguishing grid assembly;

[0012] An electromagnetic driving member connected to the moving current guide. When a positive excitation current is applied, it can generate a first electromagnetic field to cause an axial displacement of the moving current guide towards the fixed current guide, forming an electrically conductive connection; when a reverse excitation current is applied, it generates a reverse electromagnetic field to drive the moving current guide to generate a back displacement to achieve separation.

[0013] Further, the fixed current guide includes a fixed current guiding disc and a fixed current guiding column, the fixed current guiding disc is rigidly connected to the housing assembly through the fixed current guiding column; the moving current guide includes a moving current guiding disc and a moving current guiding column coaxially and fixedly connected thereto, the moving current guiding disc is disposed on the moving current guiding column, the moving current guiding column is coupled to the electromagnetic driving member, the moving current guiding column can slidably pass through the top of the housing assembly, and the moving current guiding column is provided with a terminal for an external power supply.

[0014] Further, the radially extending portions of the fixed current guiding disc and the moving current guiding disc are both equidiameter circular ring structures, and their outer diameters form a clearance fit with the maximum inner diameter of the arc extinguishing grid assembly.

[0015] Further, the electromagnetic driving member includes a lower magnet, a magnetic ring disc, a magnetic disc and an electromagnetic disc;

[0016] The lower magnet, the magnetic ring disc and the magnetic disc are all permanent magnets. The lower magnet is in the shape of a ring and is fixedly disposed near the lower part of the arc extinguishing chamber. The magnetic ring disc can move up and down in the arc extinguishing chamber and is fixed on the lower magnet by a first magnetic adsorption force generated between it and the lower magnet. The top of the magnetic ring disc is open, and the arc extinguishing grid assembly is located within the magnetic ring disc. The magnetic disc is fixed on the side of the lower magnet facing away from the magnetic ring disc, and the electromagnetic disc can move up and down between the magnetic disc and the inner bottom surface of the arc extinguishing chamber.

[0017] The moving flow guide column sequentially passes through the magnetic ring disk, the disk and the electromagnetic disk, and is fixedly connected to the electromagnetic disk, and can be slidably inserted into the disk;

[0018] When the electromagnetic disk is energized, the electromagnetic disk and the disk can generate a second adsorption force, and the second adsorption force is greater than the first magnetic adsorption force, and the electromagnetic disk can be driven to approach the disk until the moving flow guide disk contacts the fixed flow guide disk to form a conduction path through the second adsorption force.

[0019] Further, the electromagnetic driving member further includes an upper magnet, the upper magnet is a permanent magnet, the upper magnet is disposed opposite to the lower magnet and is fixedly disposed near the top of the arc extinguishing chamber, and the upper magnet and the lower magnet have the same magnetic pole arrangement and magnetic flux, constituting a symmetric magnetic circuit.

[0020] Further, the inner cross-section of the arc extinguishing grid assembly is wavy.

[0021] Further, the distances between the plurality of annular grid arc extinguishing sheets are divided into an equidistant zone and a narrowing zone. The equidistant zone is located on the side close to the fixed flow guide body, and the distances between adjacent annular grid arc extinguishing sheets in the equidistant zone are equidistantly arranged. The narrowing zone is the distance between two adjacent annular grid arc extinguishing sheets at one end close to the moving flow guide body, and the distance between the annular grid arc extinguishing sheets in the narrowing zone is less than the distance between adjacent annular grid arc extinguishing sheets in the equidistant zone.

[0022] Further, the inner wall of the magnetic ring disk is covered with an insulating lining.

[0023] Further, the distance between adjacent annular grid arc extinguishing sheets in the equidistant zone is 0.9 - 1.1 mm.

[0024] Further, the material of the housing assembly is synthetic stone.

[0025] Advantages of the present invention:

[0026] When the above metal grid arc extinguishing device is in use, when a positive excitation current is applied to the electromagnetic driving member, a strong magnetic field will be quickly generated, and a first electromagnetic field can be generated to cause an axial displacement of the moving flow guide body toward the fixed flow guide body until they are in contact, so as to form a stable conduction path, complete the conduction of the circuit, and provide a basic condition for subsequent power transmission or related electromagnetic operations.

[0027] Before the breaking operation, a reverse current is applied to the moving current-carrying fluid. At this time, a reverse electromagnetic field is generated to drive the moving current-carrying fluid to generate a backward displacement, realizing contact separation. During the breaking process, due to the sudden interruption of the current, an arc will inevitably be generated. At this time, the multi-layer annular grid arc extinguishing piece plays a role, effectively dividing and cooling the arc, thereby realizing reliable arc extinguishing, ensuring the safe operation of the equipment, and avoiding equipment damage or safety accidents caused by the arc. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In order to more clearly illustrate the specific embodiments of the present invention, the drawings required for the specific embodiments will be briefly introduced below. In all the drawings, the elements or parts are not necessarily drawn to actual scale.

[0029] Figure 1 Schematic diagram of a metal grid arc extinguishing device provided by an embodiment of the present invention;

[0030] Figure 2 is Figure 1 Schematic diagram of the magnetic ring disk with an insulating lining in the metal grid arc extinguishing device shown;

[0031] Figure 3 is Figure 1 Schematic diagram of the closing of the moving current-carrying disk and the fixed current-carrying disk in the metal grid arc extinguishing device shown;

[0032] Reference numerals:

[0033] 100, housing assembly; 200, arc extinguishing grid assembly; 210, annular grid arc extinguishing piece; 300, current-carrying assembly; 310, fixed current-carrying fluid; 311, fixed current-carrying disk; 312, fixed current-carrying column; 320, moving current-carrying fluid; 321, moving current-carrying disk; 322, moving current-carrying column; 400, electromagnetic driving member; 410, lower magnet; 420, magnetic ring disk; 430, magnetic disk; 440, electromagnetic disk; 450, upper magnet; 460, insulating lining. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0034] In order to make the above objects, features, and advantages of the present invention more obvious and understandable, the specific embodiments of the present invention will be described in detail below with reference to the drawings. Many specific details are set forth in the following description in order to fully understand the present invention. However, the present invention can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without departing from the connotation of the present invention. Therefore, the present invention is not limited by the specific embodiments disclosed below.

[0035] Please refer to Figures 1 to 3 , the present invention provides a metal grid arc extinguishing device, please refer to Figures 1 to 3, the present invention provides a metal grid arc extinguishing device, which includes a housing assembly 100, an arc extinguishing grid assembly 200, a current guiding assembly 300, and an electromagnetic driving member 400.

[0036] Specifically, the housing assembly 100 has an insulating outer shell that defines an arc extinguishing chamber. The arc extinguishing grid assembly 200 is coaxially arranged in the arc extinguishing chamber. The arc extinguishing grid assembly 200 includes a plurality of annular grid arc extinguishing sheets 210 stacked along the axial direction. The current guiding assembly 300 includes a fixed current guiding body 310 and a moving current guiding body 320 that are axially opposed. The fixed current guiding body 310 is arranged in the arc extinguishing grid assembly 200 and is close to the top of the arc extinguishing grid assembly 200.

[0037] The electromagnetic driving member 400 is connected to the moving current guiding body 320. When a positive excitation current is applied, it can generate a first electromagnetic field to cause the moving current guiding body 320 to generate an axial displacement moving towards the fixed current guiding body 310, forming an electrically conductive connection; when a reverse excitation current is applied, it generates a reverse electromagnetic field to drive the moving current guiding body 320 to generate a reverse displacement to achieve separation.

[0038] During use, when a positive excitation current is applied to the electromagnetic driving member 400, a strong magnetic field will be quickly generated, which can generate a first electromagnetic field to cause the moving current guiding body 320 to generate an axial displacement moving towards the fixed current guiding body 310 until they fit together, then a stable current guiding path can be formed to complete the conduction of the circuit, providing basic conditions for subsequent power transmission or related electromagnetic operations.

[0039] Before the breaking operation, a reverse current is passed into the moving current guiding body 320. At this time, a reverse electromagnetic field is generated to drive the moving current guiding body 320 to generate a reverse displacement to achieve contact separation. During the breaking process, due to the sudden interruption of the current, an arc will inevitably be generated. At this time, the multi-layer annular grid arc extinguishing sheets 210 play a role in effectively dividing and cooling the arc, thereby achieving reliable arc extinguishing, ensuring the safe operation of the equipment, and avoiding equipment damage or safety accidents caused by the arc.

[0040] As a preferred embodiment, in specific implementation, the inner cross-section of the arc extinguishing grid assembly 200 can be wavy. That is: the inner diameters of adjacent annular grid arc extinguishing sheets 210 are arranged in a staggered order of large and small, forming a wavy line.

[0041] This arrangement makes the path of the arc become more complex and tortuous when passing through the arc extinguishing sheet area. When the arc contacts the arc extinguishing sheet, due to the shape and arrangement characteristics of the arc extinguishing sheet, the arc will be continuously divided into multiple small parts, thereby increasing the contact area between the arc and the arc extinguishing sheet and the opportunity of interaction, creating favorable conditions for the subsequent arc extinguishing process to further improve the arc extinguishing effect. In specific implementation, the inner diameter difference between the upper and lower adjacent layers of annular grid arc extinguishing sheets 210 is controlled within less than 1 mm.

[0042] As a more preferred embodiment, the distances between multiple annular grid arc extinguishing plates 210 are divided into an equidistant region and a narrowing region. The equidistant region is located on the side close to the fixed current conductor 310, and the distances between adjacent annular grid arc extinguishing plates 210 in the equidistant region are set equally. The narrowing region is the distance between two annular grid arc extinguishing plates 210 at one end close to the moving current conductor 320. The distance between the annular grid arc extinguishing plates 210 in the narrowing region is less than the distance between adjacent annular grid arc extinguishing plates 210 in the equidistant region.

[0043] This method is based on the characteristics that the arc has higher energy and temperature in the initial stage of generation. Near the arc source, a smaller spacing can more effectively initially divide and cool the arc, restricting the development of the arc. As the arc expands outwards, the spacing between the arc extinguishing plates increases, which can not only ensure the continuous division of the arc at different positions, but also avoid affecting the flow of air and the heat dissipation effect due to too small a spacing.

[0044] Through the wavy setting and uneven spacing setting of the sizes of the annular grid arc extinguishing plates 210, the following advantages are obtained:

[0045] 1. Reduce the probability of reignition

[0046] The arc division path is shortened. Through the design of the wavy edge and the change of the spacing distance, the arc is divided into shorter paths. In the traditional arc extinguishing structure, the arc may propagate along a relatively continuous path and is prone to reignite after arc extinguishing. In this design, the arc is divided multiple times, and the length of the arc after each division becomes shorter, and its energy is relatively dispersed, making it more difficult to meet the energy conditions required for reignition. Comparative experiments show that the arc extinguishing device adopting this design compared with the traditional design, the experimental results show that the arc extinguishing time is significantly shortened, which means that the arc is effectively extinguished in a shorter time, and the possibility of reignition is greatly reduced.

[0047] Principle analysis: The reignition of the arc is usually closely related to the energy accumulation of the arc and the insulation recovery speed of the surrounding medium. When the arc is divided into short paths, the energy of each small segment of the arc is relatively low and is more easily cooled and dissipated during the arc extinguishing process. At the same time, the shorter arc path also reduces the collision chance of electrons and ions, reduces the conductivity of the arc, making it more difficult to maintain the arc, thus effectively reducing the probability of reignition.

[0048] 2. Accelerate temperature reduction

[0049] The optimized design of the variation of the spacing distance not only helps to divide the electric arc but also optimizes the air flow field. During the arc extinguishing process, the movement of the air flow plays a crucial role in taking away the heat of the electric arc. A reasonable air flow field can enable the cold air to come into contact with the hot electric arc more effectively, accelerating the heat transfer and dissipation. The design of the wavy edge and the gradient spacing guides the air flow to form a specific flow path between the arc extinguishing plates, enabling the cold air to be more evenly distributed around the electric arc and improving the heat dissipation efficiency.

[0050] During the specific implementation, research can be carried out through simulation and thermal imaging technology. The simulation results can intuitively show the flow conditions of the air flow in the arc extinguishing plate area, including parameters such as velocity distribution and pressure distribution, so as to evaluate the influence of different design schemes on the air flow field. The thermal imaging data can reflect the temperature change of the electric arc in real time. By comparing the thermal imaging images before and after adopting this design, the speed and degree of the temperature drop of the electric arc can be clearly seen. These data all support the conclusion that this design can accelerate the cooling of the electric arc, further improving the reliability and effectiveness of arc extinguishing.

[0051] In this embodiment, the fixed guide fluid 310 includes a fixed guide disk 311 and a fixed guide column 312. The fixed guide disk 311 is rigidly connected to the housing assembly 100 through the fixed guide column 312; the movable guide fluid 320 includes a movable guide disk 321 and a movable guide column 322 fixedly connected coaxially therewith. The movable guide disk 321 is arranged on the movable guide column 322. The movable guide column 322 is coupled to the electromagnetic drive member 400. The movable guide column 322 can slidably pass out from the top of the housing assembly 100. The movable guide column 322 is provided with a wiring terminal for an external power supply.

[0052] When a positive excitation current is applied to the movable guide column 322, the positive excitation current is transmitted to the electromagnetic drive member 400. The electromagnetic drive member 400 drives the movable guide disk 321 and the movable guide column 322 to move towards the fixed guide disk 311 simultaneously until the movable guide disk 321 contacts the fixed guide disk 311 to form electrical conduction. On the contrary, when a negative excitation current is applied to the movable guide column 322, the negative excitation current is transmitted to the electromagnetic drive member 400. The electromagnetic drive member 400 will move the movable guide disk 321 and the movable guide column 322 away from the fixed guide disk 311 simultaneously until the movable guide disk 321 is separated from the fixed guide disk 311.

[0053] As a preferred implementation manner, the radial extension parts of the fixed guide disk 311 and the movable guide disk 321 are both of an equal-diameter circular ring structure, and their outer diameters form a clearance fit with the maximum inner diameter of the arc extinguishing grid assembly 200.

[0054] By adopting a circular fixed flow guide disk 311 and a moving flow guide disk 321, the contact surface can be increased, thereby enhancing the arc extinguishing effect. The increased contact area of the circular conductor enables more edge regions to participate in the collaborative arc extinguishing process with the annular grid arc extinguishing piece 210.

[0055] When an arc is generated, due to the larger initial contact area provided by the circular conductor Figure 2 As shown, the arc is more widely distributed in the circumferential direction. The annular grid arc extinguishing piece 210 can more easily divide these widely distributed arcs into more short arcs, thereby more effectively increasing the near-pole voltage drop. The voltage drops of each divided short arc accumulate, enabling the total arc voltage to reach the extinguishing voltage faster, improving the arc extinguishing efficiency, and better protecting the device from the harm of the arc.

[0056] Reduce contact resistance and losses. The larger contact area can effectively reduce the contact resistance. According to the resistance law (where is the resistance, is the material resistivity, is the current path length, and is the cross-sectional area), when other conditions remain unchanged, as the contact area increases, the contact resistance decreases.

[0057] For this device, a lower contact resistance means that during normal operation, the heat loss (where is the heat, is the current, and is the time) generated when the current passes through the contact area between the conductor and the annular grid arc extinguishing piece 210 will also decrease. This not only improves the energy utilization efficiency of the device but also reduces the risk of component aging and damage caused by heating, further ensuring the stable operation of the device. Improve the adaptability and reliability of the device. In different working environments and conditions, the large-area contact characteristics of the circular conductor can provide better adaptability. For example, in the case of high current density, due to the large contact area, the current can be more effectively dispersed, avoiding local overheating and the concentration of arcs.

[0058] For external factors such as possible vibrations and impacts, the large-area contact between the circular conductor and the annular grid arc extinguishing piece 210 can provide a more stable connection. Compared with small-area contact, when the large-area contact is subjected to external interference, the relative displacement of the contact points has a smaller impact on the contact performance, thereby ensuring the stability of the collaborative arc extinguishing function between the annular grid arc extinguishing piece 210 and the conductor, and improving the reliability of the device under complex working conditions.

[0059] In this embodiment, the electromagnetic driving member 400 includes a lower magnet 410, a magnetic ring disk 420, a disk 430, and an electromagnetic disk 440;

[0060] The lower magnet 410, the magnetic ring disk 420, and the disk 430 are all permanent magnets. The lower magnet 410 is in the shape of a ring. The lower magnet 410 is fixedly arranged near the lower part of the arc extinguishing chamber. The magnetic ring disk 420 is located in the arc extinguishing chamber and can move up and down. The magnetic ring disk 420 is fixed on the lower magnet 410 by the first magnetic adsorption force generated between the magnetic ring disk 420 and the lower magnet 410. The top of the magnetic ring disk 420 is open. The arc extinguishing grid assembly 200 is located in the magnetic ring disk 420. The disk 430 is fixed on the side of the lower magnet 410 facing away from the magnetic ring disk 420. The electromagnetic disk 440 is located between the disk 430 and the inner bottom surface of the arc extinguishing chamber and can move up and down.

[0061] The moving current conducting column 322 sequentially passes through the magnetic ring disk 420, the disk 430, and the electromagnetic disk 440, and is fixedly connected to the electromagnetic disk 440 and can be slidably inserted into the disk 430.

[0062] When the electromagnetic disk 440 is energized, the electromagnetic disk 440 and the disk 430 can generate a second adsorption force, and the second adsorption force is greater than the first magnetic adsorption force. And the electromagnetic disk 440 can be driven to approach the disk 430 until the moving current conducting disk 321 contacts the fixed current conducting disk 311 to form a conduction path.

[0063] Its working principle is as follows:

[0064] Closing process:

[0065] When a positive excitation current is applied to the moving current conducting column 322, the positive excitation current is conducted to the electromagnetic disk 440 to make it energized, and then a strong first electromagnetic field will be quickly generated, forming an electromagnetic adsorption force with the upper disk 430. In this process, this electromagnetic adsorption force must first overcome the original holding magnetic force between the magnetic ring disk 420 and the lower magnet 410. Utilizing the good magnetic conductivity characteristics of the material, the magnetic ring disk 420 will move upward. As the electromagnetic disk 440 and the disk 430 gradually approach and fit, the copper contact surfaces of the moving and fixed current conducting disks are reliably connected, thereby forming a stable conduction path, completing the conduction of the circuit, and providing a basic condition for subsequent power transmission or related electromagnetic operations.

[0066] Opening process:

[0067] Before the breaking operation, the electromagnetic disk 440 and the disk 430 are in an adsorbed state. When the breaking operation is performed, a reverse current is passed through the electromagnetic disk 440 via the movable current guiding disk 321. At this time, the electromagnetic disk 440 generates an electromagnetic force repulsive to the disk 430. This repulsive force is strong enough to cause the magnetic ring disk 420 to quickly move downward and reset and adsorb to the lower magnet 410. During the breaking process, due to the sudden interruption of the current, an arc is inevitably generated. At this time, the multi-layer annular grid arc extinguishing piece 210 plays a role, effectively dividing and cooling the arc, thereby achieving reliable arc extinguishing, ensuring the safe operation of the equipment, and avoiding equipment damage or safety accidents caused by the arc.

[0068] As a preferred embodiment, the electromagnetic driving member 400 further includes an upper magnet 450. The upper magnet 450 is a permanent magnet. The upper magnet 450 is disposed opposite to the lower magnet 410 and is fixedly disposed near the top of the arc extinguishing cavity. The upper magnet 450 and the lower magnet 410 have the same magnetic pole arrangement and magnetic flux, constituting a symmetric magnetic circuit. The upper magnet 450 serves as a compensating permanent magnet to form an auxiliary adsorption on the magnetic ring disk 420.

[0069] As another more preferred embodiment, the inner wall of the magnetic ring disk 420 is covered with an insulating lining 460. In a specific implementation, the insulating lining 460 can be selected as an RTV silicone layer. The insulating lining 460 layer forms a buffer layer. If a part of the annular grid arc extinguishing piece 210 is broken down, the arc will ablate the RTV silicone, and the RTV silicone layer prevents further affecting other components.

[0070] In this embodiment, the spacing of the annular grid arc extinguishing piece 210 can be 0.9 - 1.1 mm, and the material of the annular grid arc extinguishing piece 210 can be tungsten copper alloy.

[0071] The lower magnet 410, the upper magnet 450, the magnetic ring disk 420, and the disk 430 can be made of samarium cobalt (SmCo). Samarium cobalt (SmCo) has many advantages such as excellent temperature stability, corrosion resistance, and demagnetization resistance.

[0072] The material of the housing assembly 100 can be Durostone. Durostone is a material composed of composites such as glass fiber and resin, and has the typical characteristics of Durostone. It is used to make welding trays, jigs, etc. in the field of electronic manufacturing, and can meet the requirements of high temperature resistance, high mechanical strength, and strong chemical stability.

[0073] Using the above metal grid arc extinguishing device has the following advantages:

[0074] 1. Greatly improved arc extinguishing efficiency:

[0075] This metal grid arc extinguishing device has deeply optimized the spacing and shape of its core component, the metal grid, according to the laws of arc generation, conduction, and extinction. When the circuit encounters a sudden change in current and inevitably generates an arc, the metal grid can divide the long arc it generates into numerous micro short arcs. From the physical essence of the arc, the electric field intensity and energy density of the subdivided small arcs are dispersed, the heat exchange area with the surrounding environment increases, and the ion recombination speed accelerates, making it easier to be extinguished.

[0076] A large number of experimental comparison data clearly demonstrate this advantage: Under the same harsh current intensity conditions, such as the moment of 200A current cut-off commonly seen in the DC fast charging scenario of electric vehicles, the traditional spring arc extinguishing device is limited by the mechanical action rate of spring stretching or compression and the contact separation effect, and it often takes up to 15 milliseconds to completely extinguish the arc. However, the new metal grid arc extinguishing device, with its optimized structure, fully utilizes the electromagnetic and heat conduction characteristics of the metal grid, and can make the arc disappear in about 5 milliseconds. This greatly ensures the stability of the entire electrical system under frequent on-off operations and lays a solid foundation for the reliable operation of the charging pile.

[0077] 2. Significantly enhanced working condition adaptability:

[0078] Since springs are mostly made of temperature-sensitive metal materials, as the ambient temperature rises, the thermal motion of metal atoms inside the spring intensifies, the lattice structure relaxes, resulting in a sharp drop in the elastic modulus of the spring. As a result, the contact separation speed slows down and the arc elongation effect is poor during the arc extinguishing process, and the arc extinguishing efficiency is greatly reduced. In sharp contrast, this metal grid arc extinguishing device selects special high-temperature resistant materials to make the annular grid arc extinguishing piece 210. For example, a new alloy material is used, and its melting point is as high as over 1500°C, with excellent thermal stability. Even in the hot outdoor charging pile environment or around the charging facilities near the industrial high-temperature heat source workshop, the metal grid can still maintain good electrical conductivity and thermal conductivity, and stably and reliably perform the arc extinguishing task without being interfered by high temperature at all.

[0079] 3. Simple operation and high safety:

[0080] In terms of operation, the spring of the spring arc extinguishing device is prone to fatigue after long-term use and requires professional personnel for debugging, which is time-consuming and costly. However, the metal grid arc extinguishing device has a simple and modular structure and is less affected by device fatigue. Daily maintenance personnel only need to check the metal grid and the intelligent indicator light, which is simple and easy to operate and reduces the maintenance cost. In terms of safety, the ultra-high-speed arc extinguishing can promptly eliminate the arc, providing better protection.

[0081] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements on some or all of the technical features; and these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the various embodiments of the present invention, and they should all be covered within the scope of the claims and the description of the present invention.

Claims

1. A metal grid arc extinguishing device, characterized in that, Comprising: A housing assembly having an insulating housing defining an arc extinguishing chamber; An arc extinguishing grid assembly coaxially disposed within the arc extinguishing chamber, the arc extinguishing grid assembly including a plurality of annular grid arc extinguishing sheets stacked axially; A flow guiding assembly including a stationary flow guiding body and a moving flow guiding body axially opposed to each other, the stationary flow guiding body being disposed within the arc extinguishing grid assembly and near the top of the arc extinguishing grid assembly; An electromagnetic driving member connected to the moving flow guiding body, which can generate a first electromagnetic field when a positive excitation current is applied to cause an axial displacement of the moving flow guiding body toward the stationary flow guiding body to form an electrically conductive connection; when a reverse excitation current is applied, a reverse electromagnetic field is generated to drive the moving flow guiding body to generate a backward displacement to achieve separation.

2. The metal grid arc extinguishing device according to claim 1, characterized in that, The stationary flow guiding body includes a stationary flow guiding disk and a stationary flow guiding column, and the stationary flow guiding disk is rigidly connected to the housing assembly through the stationary flow guiding column; the moving flow guiding body includes a moving flow guiding disk and a moving flow guiding column fixedly connected coaxially therewith, the moving flow guiding disk is disposed on the moving flow guiding column, the moving flow guiding column is coupled to the electromagnetic driving member, the moving flow guiding column can slidably pass through the top of the housing assembly, and the moving flow guiding column is provided with a terminal for an external power supply.

3. The metal grid arc extinguishing device according to claim 2, characterized in that, The radially extending portions of the stationary flow guiding disk and the moving flow guiding disk are both equidiameter circular ring structures, and their outer diameters form a clearance fit with the maximum inner diameter of the arc extinguishing grid assembly.

4. The metal grid arc extinguishing device according to claim 2, wherein, The electromagnetic driving member includes a lower magnet, a magnetic ring disk, a disk, and an electromagnetic disk; The lower magnet, the magnetic ring disk, and the disk are all permanent magnets. The lower magnet is in the shape of a ring and is fixedly disposed near the lower part of the arc extinguishing chamber. The magnetic ring disk can move up and down within the arc extinguishing chamber and is fixed to the lower magnet by a first magnetic adsorption force generated between it and the lower magnet. The top of the magnetic ring disk is open, and the arc extinguishing grid assembly is located within the magnetic ring disk. The disk is fixed to the side of the lower magnet facing away from the magnetic ring disk. The electromagnetic disk can move up and down between the disk and the inner bottom surface of the arc extinguishing chamber. The moving flow guiding column sequentially passes through the magnetic ring disk, the disk, and the electromagnetic disk, and is fixedly connected to the electromagnetic disk and the electromagnetic disk, and can be slidably inserted into the disk; When the electromagnetic disk is energized, the electromagnetic disk and the disk can generate a second adsorption force, and the second adsorption force is greater than the first magnetic adsorption force, and the electromagnetic disk can be driven to approach the disk until the moving flow guiding disk contacts the stationary flow guiding disk to form a conduction path.

5. The metal grid arc extinguishing device according to claim 4, characterized in that, The electromagnetic driving member further includes an upper magnet, the upper magnet is a permanent magnet, the upper magnet is disposed opposite to the lower magnet and is fixedly disposed near the top of the arc extinguishing chamber, and the upper magnet and the lower magnet have the same magnetic pole arrangement and magnetic flux, constituting a symmetric magnetic circuit.

6. The metal grid arc extinguishing device according to claim 1, characterized in that, The inner cross-section of the arc extinguishing grid assembly is wavy.

7. The metal grid arc extinguishing device according to claim 1 or 6, characterized in that, The distances between multiple said annular grid arc extinguishing plates are divided into an equidistant zone and a narrowing zone. The equidistant zone is located on the side close to the fixed current guide body. The distances between adjacent said annular grid arc extinguishing plates in the equidistant zone are set equidistantly. The narrowing zone is the distance between two said annular grid arc extinguishing plates at one end close to the moving current guide body. The distance between the annular grid arc extinguishing plates in the narrowing zone is less than the distance between adjacent said annular grid arc extinguishing plates in the equidistant zone.

8. The metal grid arc extinguishing device according to claim 4, characterized in that, The inner wall of the magnetic ring disc is covered with an insulating lining.

9. The metal grid arc extinguishing device according to claim 7, wherein, The distance between adjacent said annular grid arc extinguishing plates in the equidistant zone is 0.9 - 1.1 mm.

10. The metal grid arc extinguishing device according to claim 1, characterized in that, The material of the housing assembly is synthetic stone.

Images