Contact structure

Abstract

This application relates to contact structures, specifically to the technical field of DC contactors. The contact structure includes a lower housing with a ceramic cover inside. Two stationary contact bodies are fixedly installed inside the ceramic cover, and several honeycomb-shaped perforated circular plates are fixedly connected inside the two stationary contact bodies. This application, by incorporating the honeycomb-shaped perforated circular plates, increases the airflow space inside the contacts, effectively reducing the thermal resistance of the contacts. When current passes through the stationary contact bodies, the generated heat can be quickly dissipated through the honeycomb-shaped perforated channels, reducing the problems of increased contact resistance and decreased material performance caused by overheating. Simultaneously, it reduces the weight of the contacts, lowers material costs, and improves the heat dissipation performance and economy of the contact structure. Furthermore, the rough surface of the honeycomb perforation effectively resists electric arcs, making their movement difficult and gradually extinguishing the subsequent energy, thus improving the structure's efficiency in extinguishing electric arcs.

Description

Technical Field

[0001] This application relates to the field of DC contactor technology, and in particular to contact structure. Background Technology

[0002] Currently, common contact structures exhibit diverse characteristics in practical applications. Traditional knife-shaped contacts have a relatively simple structure and are divided into surface contact and line contact forms, and are widely used in low-voltage switch and high-voltage disconnector scenarios.

[0003] Regarding the aforementioned technologies, adopting a hollow contact structure with honeycomb-shaped hollow channels inside the contact can effectively reduce the weight of the contact itself. On the one hand, this reduces the amount of raw materials used, thereby reducing material costs. On the other hand, these hollowed-out air channels act like efficient heat dissipation "highways." When the contact generates heat due to current flow during operation, especially when an electric arc causes localized overheating, the air channels can quickly dissipate the heat, greatly alleviating the problem of contact performance degradation due to overheating. At the same time, the hollow structure increases the roughness of the contact's internal surface, making it more difficult for the electric arc to move within the contact's internal surface. During propagation, the electric arc continuously interacts with these rough surfaces, gradually consuming energy and becoming easier to extinguish, thus significantly improving the contact structure's ability to cope with the effects of electric arcs. Utility Model Content

[0004] The purpose of this application is to provide a contact structure that has the advantages of hollowed-out contacts, such as good performance, and solves the problems mentioned in the background art.

[0005] The contact structure provided in this application adopts the following technical solution: it includes a lower housing, inside which a ceramic cover is provided, and two stationary contact bodies are fixedly installed inside the ceramic cover. Several honeycomb-shaped hollow circular plates are fixedly connected inside the two stationary contact bodies. Two stepped mounting holes are fixedly connected to the top of the ceramic cover, and the stationary contact bodies are located inside the stepped mounting holes. Several square reinforcing ribs are fixedly connected to the top of the ceramic cover, and several protruding plates are fixedly connected to the inner wall surface of the ceramic cover.

[0006] By adopting the above technical solution and setting a honeycomb-shaped perforated circular plate, the air circulation space inside the contact can be increased, effectively reducing the thermal resistance of the contact. When current passes through the stationary contact body, the generated heat can be quickly dissipated through the honeycomb-shaped perforated channels, reducing the problems of increased contact resistance and deterioration of material performance caused by overheating. At the same time, the weight of the contact is reduced, material costs are lowered, and the heat dissipation performance and economy of the contact structure are improved. Moreover, the rough surface of the honeycomb perforation effectively resists the electric arc, making it difficult for the arc to move, and the subsequent energy is gradually consumed until it is extinguished, improving the structure's arc extinguishing efficiency. By setting a stepped mounting hole, the stationary contact welding piece can be embedded in the stepped surface when installing the stationary contact body. By welding and fixing, it not only strengthens the connection between the stationary contact and the ceramic cover. The connection strength ensures that the stationary contact is not easily loosened under frequent switching or vibration environments, and also makes the current conduction path more stable, reducing local overheating and arcing caused by poor contact, thus improving the electrical connection reliability of the contact structure. By setting square reinforcing ribs, a design that surrounds the annular groove can be adopted, which significantly enhances the mechanical strength of the ceramic shell. When installing the upper and lower shells, the square reinforcing ribs can effectively disperse external pressure, prevent the ceramic shell from cracking due to uneven stress, ensure the integrity of the internal structure of the ceramic shell, and thus improve the overall mechanical stability and durability of the contact structure. By setting protruding plates, the movement trajectory of the arc plasma can be disrupted, increasing its adhesion area on the inner wall of the ceramic shell, accelerating cooling, and laying the foundation for arc extinguishing of the permanent magnet.

[0007] Preferably, the top of the lower housing overlaps with the upper housing, a plurality of limiting blocks are fixedly connected to the side of the lower housing, a plurality of positioning holes are opened on the side of the upper housing, the limiting blocks are engaged inside the positioning holes, and the surfaces of the plurality of limiting blocks are all provided with inclined surfaces.

[0008] By adopting the above technical solution, and by setting limit blocks, positioning holes and inclined surfaces, the installation process of the upper and lower housings can be made more convenient and smooth. During installation, the inclined surface of the limit block guides it to quickly snap into the positioning hole, forming a stable connection structure, preventing relative displacement between the upper and lower housings during use, and ensuring the overall sealing and protection performance of the contact structure.

[0009] Preferably, the bottom of the lower housing is fixedly connected to four support legs, and the bottom ends of the four support legs are all fixedly connected to rubber blocks.

[0010] By adopting the above technical solution, and by setting up support legs and rubber blocks, the system can provide stable support and shock absorption. The support legs raise the contact structure, preventing the bottom from directly contacting the ground or mounting surface, thus preventing moisture and mechanical damage. The rubber blocks have good elasticity and can absorb vibrations during equipment operation, reducing problems such as loose contacts and poor contact caused by vibrations, thereby improving the stability of the contact structure operation.

[0011] Preferably, the surfaces of both stationary contact bodies are provided with stationary contact welding plates, the interior of the ceramic cover is provided with two auxiliary pins, the top of the two ceramic covers is provided with two annular grooves, and a number of square reinforcing ribs surround the two annular grooves.

[0012] By adopting the above technical solution and setting the stationary contact welding piece, the main functions are to strengthen the electrical connection and expand the connection methods. In the electrical connection, the stationary contact welding piece is connected to the external circuit by welding. Compared with direct connection, welding provides a more stable and low-resistance electrical path, greatly reducing contact resistance and reducing energy loss and heat generation during current transmission. By setting the auxiliary pin, it plays a key role in the contact closing and opening process. When the contact is closed, the auxiliary pin makes contact first. Through its small contact area, it can quickly pierce any oxide film or impurity layer that may exist on the contact surface, reducing contact resistance and creating favorable conditions for the complete contact of the subsequent stationary contact body, ensuring the instantaneous contact. Electrical conductivity is ensured by the auxiliary pin separating after the contacts open, which can distribute some of the arc energy, preventing the arc from concentrating on the stationary contact body, effectively reducing the degree of stationary contact erosion, and extending the service life of the stationary contact. In addition, the auxiliary pin can also play a certain guiding role, ensuring that the stationary contact is accurately aligned during the closing process, improving the accuracy and reliability of the contact structure operation. By setting an annular groove, it is mainly used for installation with the upper shell or other components. Its precise annular design provides a stable installation benchmark for the positioning and fixing of components, so that the upper shell can fit tightly with the ceramic cover after installation, effectively preventing dust, moisture and other external impurities from entering the contact structure, improving the sealing and protection performance of the contact structure.

[0013] Preferably, the inner wall surface of the ceramic cover is provided with a nano-silica coating.

[0014] By adopting the above technical solution and setting a nano-silica coating, which has good insulation and high temperature resistance, on the one hand, it can prevent the electric arc from directly contacting the ceramic shell and avoid the ceramic material from being eroded by the electric arc. On the other hand, its insulation properties can prevent the electric arc from forming a flashover on the inner wall of the ceramic shell, thereby enhancing the insulation reliability of the contact structure and reducing the probability of electrical faults.

[0015] Preferably, the surface of the protruding plate is provided with a plurality of permanent magnets, and the plurality of permanent magnets are arranged in a rectangular shape.

[0016] By adopting the above technical solution and setting permanent magnets, the arc extinguishing and protection performance can be significantly improved through the action of magnetic field in the contact structure. Specifically, it can accelerate the extinction of the arc, lengthen and diffuse the arc through Lorentz force, accelerate heat dissipation and make it cool down quickly to below the ignition point, suppress the arc diffusion, confine the arc to a specific area to avoid erosion of surrounding components, and enhance the stability of arc extinguishing. With the uniform magnetic field distribution, it ensures that the arc extinguishing effect is consistent each time. At the same time, it reduces contact wear, reduces the arc erosion of the contacts, extends the service life of the contacts, and ensures the long-term stable operation of the contact structure.

[0017] Preferably, an arc-extinguishing grid is attached to the side of the ceramic cover, and four mounting blocks are fixedly connected to the side of the arc-extinguishing grid. The interior of the mounting blocks is threadedly connected to the interior of the ceramic cover with support screws.

[0018] By adopting the above technical solution and setting up an arc-extinguishing grid, when an arc is generated, the arc enters the area of ​​the arc-extinguishing grid, and the voltage drop of each short arc increases, making it difficult for the arc to maintain combustion and accelerating its extinction. At the same time, the arc-extinguishing grid is made of high-temperature resistant and high-thermal-conductivity materials, which can quickly dissipate the heat of the arc, effectively reducing the impact of the arc on the contacts and ceramic housing, and further improving the arc-extinguishing performance and electrical safety of the contact structure.

[0019] Preferably, the end of the arc-extinguishing grid is serrated.

[0020] By adopting the above technical solution and setting a serrated shape, the electric arc can be cut into multiple short arcs, increasing the surface area, accelerating heat dissipation, and shortening the extinction time.

[0021] In summary, this application includes at least one of the following beneficial technical effects:

[0022] This contact structure, by incorporating a honeycomb-shaped perforated circular plate, increases the airflow space inside the contact, effectively reducing the thermal resistance of the contact. When current passes through the stationary contact body, the generated heat can be quickly dissipated through the honeycomb-shaped perforated channels, reducing the problems of increased contact resistance and decreased material performance caused by overheating. At the same time, it reduces the weight of the contact, lowers material costs, and improves the heat dissipation performance and economy of the contact structure. Furthermore, the rough surface of the honeycomb perforation effectively resists electric arcs, making their movement difficult, and the subsequent energy is gradually consumed until it is extinguished, improving the structure's efficiency in extinguishing electric arcs. Attached Figure Description

[0023] Figure 1 This is a schematic diagram of the overall front view structure of this application;

[0024] Figure 2 This is a schematic diagram of the overall frontal exploded structure of this application;

[0025] Figure 3 for Figure 2 Exploded cross-sectional view of the intermediate stationary contact;

[0026] Figure 4 for Figure 2 A schematic diagram of the ceramic casing from below;

[0027] Figure 5 for Figure 4 Enlarged structural diagram at point A in the middle.

[0028] In the picture:

[0029] 1. Lower housing; 2. Upper housing; 3. Positioning hole; 4. Limiting block; 5. Support leg; 6. Rubber block; 7. Ceramic cover; 8. Stationary contact body; 9. Stationary contact welding piece; 10. Auxiliary pin; 11. Square reinforcing rib; 12. Annular groove; 13. Stepped mounting hole; 14. Honeycomb-shaped hollow circular plate; 15. Nano-silica coating; 16. Raised plate; 17. Permanent magnet; 18. Arc extinguishing grid plate; 19. Mounting block; 20. Support screw; 21. Serrated. Detailed Implementation

[0030] The following is in conjunction with the appendix Figure 1 -Appendix Figure 5 This application will be described in further detail below.

[0031] Example 1: Contact structure, refer to Figure 1 , Figure 2 , Figure 3 and Figure 4The device includes a lower housing 1, inside which is a ceramic cover 7. Two stationary contact bodies 8 are fixedly installed inside the ceramic cover 7. Several honeycomb-shaped perforated circular plates 14 are fixedly connected inside the two stationary contact bodies 8. Two stepped mounting holes 13 are fixedly connected to the top of the ceramic cover 7, and the stationary contact bodies 8 are located inside the stepped mounting holes 13. Several square reinforcing ribs 11 are fixedly connected to the top of the ceramic cover 7. Several protruding plates 16 are fixedly connected to the inner wall surface of the ceramic cover 7. By setting the honeycomb-shaped perforated circular plates 14, the airflow space inside the contacts can be increased, effectively reducing the thermal resistance of the contacts. When current passes through the stationary contact bodies 8, the generated heat can be quickly dissipated through the honeycomb-shaped perforated channels, reducing the problem of increased contact resistance and decreased material performance caused by overheating. At the same time, it reduces the weight of the contacts, lowers material costs, and improves the heat dissipation performance and economy of the contact structure. Furthermore, the rough surface of the honeycomb perforation effectively resists electric arcs, making their movement difficult, and the subsequent energy is gradually consumed until it is extinguished, improving... The structure improves arc extinguishing efficiency by providing stepped mounting holes 13, allowing the stationary contact welding piece 9 to be embedded in the stepped surface during installation of the stationary contact body 8. This welding not only enhances the connection strength between the stationary contact and the ceramic housing 7, ensuring the stationary contact is less prone to loosening under frequent switching or vibration environments, but also stabilizes the current conduction path, reducing localized overheating and arcing caused by poor contact, thus improving the electrical connection reliability of the contact structure. The square reinforcing ribs 11, designed to surround the annular groove 12, significantly enhance the mechanical strength of the ceramic housing 7. During installation of the upper housing 2 and lower housing 1, the square reinforcing ribs 11 effectively disperse external pressure, preventing the ceramic housing 7 from cracking due to uneven stress, ensuring the integrity of the internal structure of the ceramic housing 7, and thereby improving the overall mechanical stability and durability of the contact structure. The protruding plate 16 disrupts the trajectory of the arc plasma, increasing its adhesion area on the inner wall of the ceramic housing 7, accelerating cooling, and laying the foundation for arc extinguishing by the subsequent permanent magnet.

[0032] Please see Figure 1The upper shell 2 overlaps the top of the lower shell 1. Several limiting blocks 4 are fixedly connected to the side of the lower shell 1. Several positioning holes 3 are opened on the side of the upper shell 2. The limiting blocks 4 are engaged inside the positioning holes 3. The surfaces of the limiting blocks 4 are all provided with bevels. By setting the limiting blocks 4, positioning holes 3 and bevels, the installation process of the upper shell 2 and the lower shell 1 can be made more convenient and smooth. During installation, the bevels of the limiting blocks 4 guide them to quickly engage with the positioning holes 3, forming a stable connection structure, preventing relative displacement between the upper shell 2 and the lower shell 1 during use, and ensuring safety. To ensure the overall sealing and protection performance of the contact structure, four support legs 5 are fixedly connected to the bottom of the lower housing 1. Each of the four support legs 5 has a rubber block 6 fixedly connected to its bottom end. By setting the support legs 5 and the rubber blocks 6, the contact structure can be stabilized and damped. The support legs 5 raise the contact structure to prevent the bottom from directly contacting the ground or mounting surface, thus preventing moisture and mechanical damage. The rubber blocks 6 have good elasticity and can absorb vibrations during equipment operation, reducing problems such as loose contacts and poor contact caused by vibration, thereby improving the stability of the contact structure operation.

[0033] Please see Figure 2 and Figure 4Both stationary contact bodies 8 have stationary contact welding pieces 9 on their surfaces. Two auxiliary pins 10 are located inside the ceramic housing 7. Two annular grooves 12 are formed on the top of the two ceramic housings 7, and several square reinforcing ribs 11 surround the two annular grooves 12. The stationary contact welding pieces 9 primarily strengthen the electrical connection and expand the connection methods. In the electrical connection, the stationary contact welding pieces 9 are connected to the external circuitry by welding. Compared to direct connection, welding provides a more stable and lower-resistance electrical path, greatly reducing contact resistance and minimizing energy loss and heat generation during current transmission. The auxiliary pins 10 play a crucial role in the contact closing and opening process. When the contact closes, the auxiliary pins 10 make contact first. Through their small contact area, they can quickly pierce any oxide film or impurity layer that may exist on the contact surface, reducing contact resistance and creating favorable conditions for the subsequent complete contact of the stationary contact bodies 8, ensuring electrical conductivity at the moment of contact. When the contact opens, the auxiliary pins 10 separate later, sharing some of the arc energy and avoiding... The arc-free system concentrates the force on the stationary contact body 8, effectively reducing the degree of erosion of the stationary contact and extending its service life. In addition, the auxiliary pin 10 can also play a certain guiding role, ensuring accurate alignment of the stationary contact during the closing process, improving the precision and reliability of the contact structure's operation. The annular groove 12 is mainly used for installation with the upper housing 2 or other components. Its precise annular design provides a stable installation benchmark for the positioning and fixing of the components, allowing the upper housing 2 to fit tightly with the ceramic cover 7 after installation, effectively preventing dust, moisture and other external impurities from entering the contact structure, improving the sealing and protective performance of the contact structure. The inner wall surface of the ceramic cover 7 is provided with a nano-silica coating 15. By providing the nano-silica coating 15, due to its good insulation and high temperature resistance, on the one hand, it can prevent the arc from directly contacting the ceramic cover 7, avoiding the ceramic material from being eroded by the arc. On the other hand, its insulation properties can prevent the arc from forming a flashover on the inner wall of the ceramic cover 7, enhancing the insulation reliability of the contact structure and reducing the probability of electrical faults.

[0034] Please see Figure 4 and Figure 5The surface of the raised plate 16 is provided with several permanent magnets 17 arranged in a rectangular pattern. By setting the permanent magnets 17, the arc extinguishing and protection performance is significantly improved through the magnetic field effect in the contact structure. Specifically, it can accelerate arc extinguishing, elongate and diffuse the arc through the Lorentz force, accelerate heat dissipation to quickly cool it below the ignition point, suppress arc diffusion, confine the arc to a specific area to avoid eroding surrounding components, and enhance arc extinguishing stability. The uniform magnetic field distribution ensures consistent arc extinguishing effect each time, while reducing contact wear, reducing arc erosion of the contacts, extending contact life, and ensuring long-term stable operation of the contact structure. Arc extinguishing grids 18 are overlapped on the side of the ceramic cover 7 to extinguish the arc. Four mounting blocks 19 are fixedly connected to the side of the arc-extinguishing grid 18. The interior of the mounting blocks 19 is threadedly connected to the interior of the ceramic housing 7 with support screws 20. By setting the arc-extinguishing grid 18, when an arc is generated, the arc enters the area of ​​the arc-extinguishing grid 18, and the voltage drop of each short arc increases, making it difficult for the arc to maintain combustion and accelerating its extinction. At the same time, the arc-extinguishing grid 18 is made of high-temperature resistant and high thermal conductivity material, which can quickly dissipate the heat of the arc, effectively reducing the impact of the arc on the contacts and the ceramic housing 7, further improving the arc-extinguishing performance and electrical safety of the contact structure. The end of the arc-extinguishing grid 18 is serrated 21. By setting the serration 21, the arc can be cut into multiple short arcs, increasing the surface area to accelerate heat dissipation and shorten the extinction time.

[0035] The implementation principle of this application embodiment is as follows: First, the auxiliary pin 10, with its smaller contact area, makes initial contact with the moving contact, piercing the oxide film or impurity layer that may exist on the contact surface, reducing the contact resistance, and creating a low-resistance path for the complete contact of the subsequent stationary contact body 8. Then, the stationary contact body 8 gradually completes the closure, forming a stable welded connection with the external circuit through the stationary contact solder pad 9 on the surface, ensuring low resistance and high reliability of the current transmission path.

[0036] Then, when the current passes through the stationary contact body 8, the honeycomb-shaped hollow circular plate 14 inside it plays a role in increasing the air circulation space, quickly dissipating the heat generated by the current, reducing thermal resistance, and preventing the contact resistance from increasing due to overheating. At the same time, the nano-silica coating 15 on the inner wall of the ceramic cover 7 isolates the electric arc from the ceramic material, prevents flashover, and ensures insulation performance.

[0037] Then, the auxiliary needle 10 separates from the stationary contact body 8, sharing some of the arc energy and reducing the ablation of the stationary contact body 8. Subsequently, the arc is generated and enters the arc extinguishing stage. The protruding plate 16 on the inner wall of the ceramic cover 7 disrupts the trajectory of the arc plasma, increases its attachment area on the inner wall of the ceramic cover 7, and accelerates cooling. Then, the permanent magnets 17 arranged in a rectangle generate a magnetic field, which stretches and diffuses the arc through the Lorentz force, further accelerating the arc cooling.

[0038] Subsequently, the electric arc enters the region of the arc-extinguishing grid 18 under the action of the magnetic field. The serrated structure 21 at the end of the arc-extinguishing grid 18 divides the electric arc into multiple short arcs, increasing the total length and surface area of ​​the electric arc and accelerating heat dissipation. Then, the total voltage drop of the multiple short arcs exceeds the power supply voltage, the electric arc energy is exhausted and it is quickly extinguished. The high thermal conductivity material of the arc-extinguishing grid 18 simultaneously dissipates the remaining heat, completing the arc extinguishing process. Throughout the process, the square reinforcing rib 11 enhances the mechanical strength of the ceramic shell 7, the limiting block 4, the positioning hole 3, and the annular groove 12 ensure the sealing of the shell, and the support leg 5 and the rubber block 6 ensure the stable operation of the structure.

[0039] Finally, when the arc-extinguishing grid plate 18 needs to be repaired or replaced, the positioning hole 3 on the upper housing 2 is disengaged from the limiting block 4, the upper housing 2 is then removed, the ceramic cover 7 is then taken out, and the arc-extinguishing grid plate 18 is removed by turning the support screw 20 for repair.

[0040] The embodiments described in this specific implementation are preferred embodiments of this application and are not intended to limit the scope of protection of this application. Identical components are represented by the same reference numerals. Therefore, all equivalent changes made to the structure, shape, and principle of this application should be covered within the scope of protection of this application.

Claims

1. Contact structure comprising a lower housing (1), characterized in that: The lower housing (1) is provided with a ceramic cover (7) inside. Two stationary contact bodies (8) are fixedly installed inside the ceramic cover (7). Several honeycomb-shaped hollow circular plates (14) are fixedly connected inside the two stationary contact bodies (8). Two stepped mounting holes (13) are fixedly connected to the top of the ceramic cover (7). The stationary contact bodies (8) are located inside the stepped mounting holes (13). Several square reinforcing ribs (11) are fixedly connected to the top of the ceramic cover (7). Several protruding plates (16) are fixedly connected to the inner wall surface of the ceramic cover (7).

2. The contact structure of claim 1, wherein: The top of the lower housing (1) is connected to the upper housing (2). Several limiting blocks (4) are fixedly connected to the side of the lower housing (1). Several positioning holes (3) are opened on the side of the upper housing (2). The limiting blocks (4) are engaged in the interior of the positioning holes (3). The surfaces of the limiting blocks (4) are all provided with inclined surfaces.

3. The contact structure of claim 1, wherein: The bottom of the lower housing (1) is fixedly connected to four support legs (5), and the bottom ends of the four support legs (5) are all fixedly connected to rubber blocks (6).

4. The contact structure of claim 1, wherein: The surfaces of the two stationary contact bodies (8) are provided with stationary contact welding plates (9), and the interior of the ceramic cover (7) is provided with two auxiliary pins (10). The tops of the two ceramic cover bodies (7) have two annular grooves (12), and several square reinforcing ribs (11) surround the two annular grooves (12).

5. The contact structure of claim 1, wherein: The inner wall surface of the ceramic cover (7) is provided with a nano-silica coating (15).

6. The contact structure of claim 1, wherein: The surface of the protruding plate (16) is provided with a plurality of permanent magnets (17), which are arranged in a rectangular shape.

7. The contact structure of claim 1, wherein: The ceramic cover (7) has an arc-extinguishing grid plate (18) attached to its side. The side of the arc-extinguishing grid plate (18) is fixedly connected to four mounting blocks (19). The interior of the mounting blocks (19) is threadedly connected to the interior of the ceramic cover (7) with a support screw (20).

8. The contact structure of claim 7, wherein: The end of the arc-extinguishing grid (18) is serrated (21).

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