High-voltage direct-current contactor sealing process and high-voltage direct-current contactor

Abstract

The invention discloses a high-voltage direct-current contactor sealing process and a high-voltage direct-current contactor, and the sealing process comprises the following steps: providing a ceramic assembly, a magnetic conductive plate, an iron core sleeve and a sealing sheet, carrying out the laser welding after the assembly to form a preliminary sealing assembly, and transferring the preliminary sealing assembly into sealing equipment; placing the sealing piece at the gas path through hole in the ceramic assembly or the magnetic conductive plate, and enabling the integrated connector to be attached to the peripheral area of the gas path through hole; the vacuumizing device vacuumizes the sealed cavity through the multi-way pipe fitting, and after the vacuum degree reaches the preset requirement, the vacuumizing device is closed; the inflating device is used for inflating protective gas into the sealed cavity through the multi-way pipe fitting; after air inflation is completed, the air inflation device is closed; the electric resistance welding device pushes the sealing piece to abut against the ceramic assembly or the magnetic conductive plate through the electric resistance welding connector and adopts the electric resistance welding technology to weld the sealing piece so as to completely seal the gas circuit through hole. The production efficiency can be improved, the cost and the product leakage rate are reduced, and the long-term sealing performance is improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of direct current contactors, in particular to a high-voltage direct current contactor sealing process and a high-voltage direct current contactor. BACKGROUND

[0002] As a core control component in the fields of new energy vehicles, energy storage systems and smart grids, the high-voltage direct current relay is often accompanied by arc generation and arc extinguishing operation in its working process. To avoid internal component oxidation corrosion or insulation performance degradation, it is necessary to isolate moisture, dust and other impurities in the external air through a reliable sealing structure, so as to ensure long-term stable operation of the component. Therefore, the sealing process is the key core technology to determine the reliability, service life and application safety of the high-voltage direct current relay product, and the rationality of the process directly affects the production cost, production efficiency and sealing performance of the product.

[0003] At present, there are two typical technical solutions for the sealing process of high-voltage direct current relays in the industry, but both have significant technical defects, as follows: The first solution takes ceramic components, magnetic plates and core housings as the core components of the sealing cavity. First, the exhaust pipe is connected to the magnetic plate by vacuum brazing process, then the connection parts of the ceramic components, magnetic plates and core housings are welded by laser welding process; then the sealing cavity surrounded by the ceramic components, magnetic plates and core housings is vacuumized through the exhaust pipe, and then the cavity is filled with protective gas; finally, the end of the exhaust pipe is pinched to block the gas flow between the sealing cavity and the outside, realizing the final sealing. This way not only has high cost, but also needs additional soldering during brazing process. Moreover, the sealing reliability is low, because the final sealing of the exhaust pipe relies on pinching, which is a mechanical sealing structure. Affected by factors such as uniformity of pinching pressure, consistency of plastic deformation of exhaust pipe material, etc., the actual application has a high probability of gas leakage, which easily leads to leakage of internal protective gas or intrusion of external impurities, affecting the performance stability of the component.

[0004] The second solution directly realizes overall sealing by resistance welding, but the ceramic components, magnetic plates and core housings need to be assembled and placed in a protective gas atmosphere before being welded by resistance welding process. Although this solution eliminates the exhaust pipe structure, resistance welding needs to cover the entire connection area of the magnetic plate, ceramic component and core housing, resulting in a large welding area. Therefore, a high-power resistance welding device is needed to ensure the welding depth and sealing performance, which not only consumes a lot of energy, but also causes long welding time per unit, seriously restricting production efficiency. Moreover, the maintenance cost of the protective gas atmosphere is high, and the welding environment is harsh.

[0005] Therefore, developing a high-voltage DC relay sealing process capable of avoiding the above defects, taking into account low cost, high efficiency and high sealing reliability, has become a technical requirement urgently needed to be solved in the field. SUMMARY

[0006] The problem to be solved by the present application is to provide a high-voltage DC contactor sealing process and a high-voltage DC contactor to overcome the defects of high cost, high leakage rate and low efficiency of the existing high-voltage DC contactor sealing process.

[0007] The technical scheme adopted by the present application to solve its technical problems is: a high-voltage DC contactor sealing process, comprising the following steps: S1, providing a ceramic assembly, a magnetic conducting plate, a core sleeve and a sealing piece, the ceramic assembly or the magnetic conducting plate is provided with an air passage hole; S2, sequentially assembling the ceramic assembly, the magnetic conducting plate and the core sleeve and then performing laser welding to form a preliminary sealing combination around a predetermined sealed cavity, the air passage hole leading to the sealed cavity; S3, transferring the preliminary sealing combination to a sealing device; wherein the sealing device comprises a vacuum pumping device, a gas filling device, a resistance welding device and an integrated joint, the integrated joint comprises a multi-pass pipe fitting, a corrugated pipe and a resistance welding joint, the resistance welding joint is provided in the multi-pass pipe fitting and the corrugated pipe, and the multi-pass pipe fitting is sealed and connected to the sealing plate at one end of the resistance welding joint through the corrugated pipe; S4, placing the sealing piece at the air passage hole on the ceramic assembly or the magnetic conducting plate, and making the integrated joint fit with the peripheral area of the air passage hole; at this time, the other end of the resistance welding joint is distributed opposite to the sealing piece, and a moving space is left for the sealing piece; S5, the vacuum pumping device pumps the sealed cavity through the multi-pass pipe fitting; when the vacuum degree inside the sealed cavity reaches the predetermined requirement, the vacuum pumping device is closed; the gas filling device fills the sealed cavity with protective gas through the multi-pass pipe fitting; after the gas filling is completed, the gas filling device is closed; S6, the resistance welding device pushes the sealing piece to abut against the ceramic assembly or the magnetic conducting plate through the resistance welding joint, and adopts resistance welding process to weld the sealing piece to completely seal the air passage hole.

[0008] As a further improvement of the present application, the ceramic assembly comprises a ceramic cover, a connecting ring and two static contacts, the connecting ring is brazed to the bottom of the ceramic cover, and two static contacts are brazed side by side to the top of the ceramic cover; in step S1, if the air passage hole is selected to be opened on the ceramic assembly, the air passage hole is located on the ceramic cover.

[0009] As a further improvement of the application, the ceramic assembly further comprises a sealing ring, which is brazed to the peripheral area of the gas passage hole of the ceramic cover; in step S6, the sealing sheet is attached to the sealing ring and fixedly connected by resistance welding under the pushing of the resistance welding head.

[0010] As a further improvement of the application, in step S2, the connecting ring is welded to the top surface of the magnetic conducting plate, and the core sleeve is welded to the bottom surface of the magnetic conducting plate.

[0011] As a further improvement of the application, one end of the multi-pass pipe is open and welded to the corrugated pipe, and the other end is fixed with a sealing ring; in step S4, the integrated joint is tightly attached to the peripheral area of the gas passage hole of the ceramic assembly or the magnetic conducting plate through the sealing ring.

[0012] As a further improvement of the application, the outer peripheral surface of the multi-pass pipe is provided with a gas extraction port and a gas filling port, both of which are connected to the sealed cavity through the internal cavity of the multi-pass pipe and the gas passage hole; the vacuum extraction device is connected to the gas extraction port, and the gas filling device is connected to the gas filling port.

[0013] As a further improvement of the application, the gas passage hole is provided on the magnetic conducting plate, and the bottom surface of the magnetic conducting plate is provided with a receiving groove around the gas passage hole; in step S4, the sealing sheet is placed in the receiving groove and is blocked by the resistance welding head.

[0014] As a further improvement of the application, the receiving groove is provided with a welding ring distributed around the gas passage hole; in step S6, the resistance welding device applies a pushing force to the integrated joint towards the magnetic conducting plate, so that the resistance welding head pushes the sealing sheet against the welding ring, and at the same time, the corrugated pipe is compressed, and then the sealing sheet and the welding ring are sealed and welded by resistance welding process.

[0015] As a further improvement of the application, in step S6, the parameters of the resistance welding process are as follows: the welding current is 800-2000 A, the welding pressure is 10-50 N, the welding power-on time is 0.3-1.5 s, and the diameter of the welding spot after welding is 1-3 mm.

[0016] The application also provides a high-voltage DC contactor, which comprises a ceramic assembly, a magnetic conducting plate, a core sleeve and a sealing sheet, and the ceramic assembly, the magnetic conducting plate, the core sleeve and the sealing sheet are sealed and connected by the high-voltage DC contactor sealing process as described above.

[0017] The application has the beneficial effects that the application provides a high-voltage direct-current contactor sealing process and a high-voltage direct-current contactor, the initial sealing of a ceramic assembly, a magnetic conductive plate and a core sleeve is realized through laser welding, and then the sealing piece is sealed and welded on the gas passage hole through a resistance welding process to realize the final sealing of the sealed cavity, significantly reduce the product leakage rate and improve the long-term sealing performance of the sealed cavity; at the same time, the resistance welding is only for a small-area sealing piece, without the need of high-power equipment, thereby reducing the production cost and improving the production efficiency; in addition, the integrated joint of the sealing equipment realizes the three functions of vacuumizing, gas filling and resistance welding, without the need of transferring the workpiece between different equipment, reducing the process switching time, without the need of additional adjustment of the workpiece position, and the cavity environment regulation and sealing can be completed in a single process, thereby further greatly improving the production efficiency; further, the integrated joint is closely attached to the peripheral area of the gas passage hole of the magnetic conductive plate through a sealing ring, forming a flexible sealing, avoiding the gas leakage of the interface during the vacuumizing and gas filling process, ensuring the vacuum degree of the cavity and the purity of the protective gas, and the elastic property of the bellows can compensate the coaxiality error and height deviation between the integrated joint and the ceramic assembly or the magnetic conductive plate, without the need of high-precision adjustment equipment alignment, thereby reducing the equipment debugging difficulty. BRIEF DESCRIPTION OF DRAWINGS

[0018] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following will briefly introduce the drawings needed to be used in the embodiments. Obviously, the drawings in the following description only some embodiments of the present application, and for those skilled in the art, other drawings can be obtained without creative labor on the basis of these drawings.

[0019] Figure 1 The step block diagram of the high-voltage direct-current contactor sealing process of the application; Figure 2 The perspective view of the high-voltage direct-current contactor and the integrated joint of the first embodiment of the application; Figure 3 The cross-sectional view of the high-voltage direct-current contactor and the integrated joint of the first embodiment of the application; Figure 4 The perspective view of the high-voltage direct-current contactor after sealing of the first embodiment of the application; Figure 5 The cross-sectional view of the high-voltage direct-current contactor and the integrated joint of the second embodiment of the application; Figure 6 The perspective view of the high-voltage direct-current contactor after sealing of the second embodiment of the application.

[0020] The following description is made in combination with the drawings: 1. Ceramic component; 11. Ceramic cover; 12. Connecting ring; 13. Stationary contact; 14. Sealing ring; 2. Magnetic guide plate; 201. Receiving groove; 202. Welding ring; 3. Iron core sleeve; 4. Sealing plate; 5. Multi-port fitting; 501. Air extraction port; 502. Air filling port; 6. Bellows; 7. Resistance welding head; 701. Sealing plate; 8. Sealing ring; 10. Air passage hole; 20. Sealing cavity. Detailed Implementation

[0021] The following specific examples illustrate the implementation of this application. Those skilled in the art can easily understand other advantages and effects of this application from the content disclosed in this specification. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of them. This application can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of this application. It should be noted that, in the absence of conflict, the following embodiments and features in the embodiments can be combined with each other. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0022] It should be noted that various aspects of embodiments within the scope of the appended claims are described below. It will be apparent that the aspects described herein can be embodied in a wide variety of forms, and any particular structure and / or function described herein is merely illustrative. Based on this application, those skilled in the art will understand that one aspect described herein can be implemented independently of any other aspect, and two or more of these aspects can be combined in various ways. For example, any number and aspects set forth herein can be used to implement the device and / or practice the method. Additionally, this device and / or method can be implemented using structures and / or functionalities other than one or more of the aspects set forth herein.

[0023] It should also be noted that the illustrations provided in the following embodiments are only schematic representations of the basic concept of this application. The illustrations only show the components related to this application and are not drawn according to the number, shape and size of the components in actual implementation. In actual implementation, the form, quantity and proportion of each component can be arbitrarily changed, and the layout of the components may also be more complex.

[0024] Additionally, specific details are provided in the following description to facilitate a thorough understanding of the examples. However, those skilled in the art will understand that practice can be carried out without these specific details.

[0025] The technical solutions provided by the various embodiments of this application are described below with reference to the accompanying drawings. Example 1

[0026] See Figures 1 to 4 The present invention provides a high-voltage DC contactor sealing process, including the following steps S1 to S6.

[0027] S1 provides a ceramic component 1, a magnetic conductive plate 2, an iron core sleeve 3, and a sealing plate 4; wherein, the magnetic conductive plate 2 has a pre-drilled air passage hole 10, which extends along the thickness direction of the magnetic conductive plate 2 and penetrates the top and bottom surfaces of the magnetic conductive plate 2. The air passage hole 10 serves as a channel connecting the sealed cavity 20 for vacuuming and gas filling operations.

[0028] S2, ceramic component 1, magnetic plate 2 and iron core sleeve 3 are assembled in sequence and then laser welded to form a preliminary sealed assembly around the preset sealed cavity 20. The air passage hole 10 on the magnetic plate 2 leads to the sealed cavity 20.

[0029] S3, transfer the preliminary sealing assembly to the sealing equipment.

[0030] In this invention, the sealing equipment includes a vacuuming device, a gas filling device, a resistance welding device, and an integrated connector. The integrated connector includes a multi-port fitting 5, a corrugated pipe 6, and a resistance welding head 7. The resistance welding head 7 passes through the multi-port fitting 5 and the corrugated pipe 6, and one end of the resistance welding head 7 is provided with a sealing plate 701. The multi-port fitting 5 is sealed to the sealing plate 701 through the corrugated pipe 6.

[0031] S4, place the sealing piece 4 at the air passage hole 10 on the ceramic component 1 or the magnetic plate 2, and make the integrated connector fit tightly with the surrounding area of ​​the air passage hole 10; at this time, the other end of the resistance welding head 7 is distributed opposite to the sealing piece 4, and leaves room for the sealing piece 4 to move, so that there is a gap between the sealing piece 4 and the magnetic plate 2, which will not block the air passage hole 10, and ensure subsequent vacuuming and gas filling operations.

[0032] S5, the vacuuming device evacuates the sealed cavity 20 through the multi-port fitting 5 and the gas passage 10; when the vacuum level inside the sealed cavity 20 reaches the preset requirement, the vacuuming device is turned off; then, the gas filling device fills the sealed cavity 20 with protective gas through the multi-port fitting 5 and the gas passage 10; after the gas filling is completed and the pressure of the protective gas inside the sealed cavity 20 is stable, the gas filling device is turned off.

[0033] S6, the resistance welding device pushes the sealing plate 4 against the magnetic plate 2 through the resistance welding head 7, and uses resistance welding process to weld the sealing plate 4 to completely seal the gas passage hole 10.

[0034] This invention first achieves preliminary sealing of the ceramic component 1, magnetic plate 2, and iron core sleeve 3 through laser welding. Then, it uses resistance welding to seal the sealing piece 4 to the gas passage 10, achieving final sealing of the sealed cavity 20. This eliminates the exhaust pipe structure that relies on clamp sealing in existing processes, significantly reducing product leakage rate and improving the long-term sealing performance of the sealed cavity 20. At the same time, resistance welding is only required for small-area sealing pieces 4, eliminating the need for high-power equipment, reducing production costs and improving production efficiency. Furthermore, the integrated connector of the sealing equipment integrates vacuuming, gas filling, and resistance welding functions, eliminating the need to transfer workpieces between different devices, reducing process changeover time. Moreover, the resistance welding head 7 is coaxially designed with the gas extraction and gas filling channels, eliminating the need for additional workpiece position adjustments. A single process can complete cavity environment control and sealing, further significantly improving production efficiency.

[0035] like Figure 3 As shown, the ceramic component 1 in this invention includes a ceramic cover 11, a connecting ring 12, and two stationary contacts 13. The connecting ring 12 is brazed to the bottom of the ceramic cover 11, and the two stationary contacts 13 are brazed side by side to the top of the ceramic cover 11.

[0036] In this embodiment, the bottom of the connecting ring 12 is provided with a first outward flange; the iron core sleeve 3 is a round cup shape with a bottom but no top, and its top is provided with a second outward flange around the port.

[0037] In step S2, the entire circumference of the first outer flange of the connecting ring 12 is laser-welded to the top surface of the magnetic plate 2, and the entire circumference of the second outer flange of the iron core sleeve 3 is laser-welded to the bottom surface of the magnetic plate 2, thereby forming a preliminary sealed assembly. The laser welding process results in narrow welds, high efficiency, and structural stability.

[0038] In this invention, the welding sequence of the ceramic component 1, the magnetic plate 2, and the iron core sleeve 3 is arbitrary and not required.

[0039] It is understandable that the high-voltage DC contactor also includes a moving contact plate, a push rod, and an iron core located inside the sealed cavity 20. Before laser welding in step S2, these components need to be installed on the magnetic plate 2 before laser welding can be performed.

[0040] See Figure 3 In this embodiment, the multi-way fitting 5 is specifically a four-way fitting. Both axial ends of the multi-way fitting 5 are open, and one end is welded to the bellows 6, while the other end is fixed with a sealing ring 8. The sealed connection between the bellows 6, the multi-way fitting 5, and the resistance welding head 7 prevents external air from entering, further ensuring the accuracy of cavity environment control.

[0041] In step S4, the integrated connector is tightly fitted to the area surrounding the air passage hole 10 of the magnetic plate 2 via the sealing ring 8, forming a flexible seal to prevent air leakage at the interface during vacuuming and inflation, thus ensuring the vacuum level of the cavity and the purity of the protective gas. Simultaneously, the elastic properties of the bellows 6 can compensate for the coaxiality error and height deviation between the integrated connector and the magnetic plate 2, eliminating the need for high-precision equipment alignment adjustments and reducing the difficulty of equipment debugging.

[0042] The multi-port fitting 5 has an air extraction port 501 and an air filling port 502 on its outer circumferential surface. Both the air extraction port 501 and the air filling port 502 are connected to the sealed cavity 20 through the internal cavity of the multi-port fitting 5 and the air passage 10. The vacuuming device is connected to the air extraction port 501, and the air filling device is connected to the air filling port 502.

[0043] In step S5, after the vacuuming device completes the vacuuming, it closes the vacuuming pipeline through the solenoid valve; similarly, after the inflation device completes the inflation, it closes the inflation pipeline through the solenoid valve to ensure the sealing of the integrated connector and the sealed cavity 20, preventing air from entering and protective gas from overflowing.

[0044] Of course, in other embodiments of the present invention, the multi-port fitting 5 can also be a three-port fitting, that is, the vacuum port 501 and the inflation port 502 share a common through hole, and the vacuuming pipeline and the inflation pipeline can be opened and closed by logic control through a solenoid valve. This is the existing conventional technology and is not the part to be improved in this application, so it will not be elaborated further.

[0045] It should be noted that the vacuuming device used to achieve the vacuuming operation of the sealed cavity 20 and the gas filling device used to fill the sealed cavity 20 with protective gas both adopt conventional equipment structures and models known to those skilled in the art, and do not involve any improvement to the structure of such equipment itself.

[0046] Optionally, the protective gas filled into the sealed cavity 20 can be one of nitrogen, argon or helium, or a mixture of the above gases in any proportion.

[0047] Continue reading Figure 3 The bottom surface of the magnetic plate 2 has a receiving groove 201 surrounding the air passage 10, and the diameter of the receiving groove 201 is slightly larger than that of the sealing piece 4. In step S4, the sealing piece 4 is placed in the receiving groove 201 and is blocked and limited by the resistance welding head 7. The receiving groove 201 on the bottom surface of the magnetic plate 2 can directly pre-position the sealing piece 4. After the sealing piece 4 is placed in the receiving groove 201, it remains stable. At the same time, the blocking and limiting effect of the resistance welding head 7 can prevent the sealing piece 4 from shifting or falling off during vacuuming and gas filling, thus improving process stability.

[0048] It is worth mentioning that the receiving groove 201 is provided with welding rings 202 distributed around the gas passage 10. In step S6, the resistance welding device applies a pushing force towards the guide magnetic plate 2 to the integrated joint, causing the resistance welding head 7 to push the sealing piece 4 against the welding rings 202, while simultaneously compressing the bellows 6. Then, the resistance welding process is used to seal the sealing piece 4 to the welding rings 202. The welding rings 202 in the receiving groove 201 are distributed around the gas passage 10, providing an annular welding position for the sealing piece 4. Compared with planar welding, this can form a continuous sealing weld, completely blocking the communication between the gas passage 10 and the outside.

[0049] The resistance welding device is equipped with a welding head drive device, such as a cylinder, which is connected to the integrated joint to push the sealing piece 4 against the welding ring 202 by the resistance welding head 7 in step S6.

[0050] In step S6, the resistance welding head 7 is electrically connected to the positive terminal of the resistance welding device, and the magnetic plate 2 is electrically connected to the negative terminal of the resistance welding device to perform resistance welding. The parameters of the resistance welding process are: welding current of 800~2000A, welding pressure of 10~50N, welding energizing time of 0.3~1.5s, and the diameter of the weld point after welding is 1~3mm. These resistance welding process parameters can ensure that the sealing plate 4 and the magnetic plate 2 form an effective sealing connection, while avoiding excessive pressure causing deformation of the sealing plate 4 or insufficient pressure causing poor welding. Example 2

[0051] The difference between this embodiment and Embodiment 1 is that the gas passage 10 is provided on the ceramic component 1.

[0052] Specifically, see Figure 5 and Figure 6 In the ceramic component 1 provided in step S1, the top of the ceramic cover 11 has a pre-existing air passage hole 10, which extends vertically and penetrates the top and bottom surfaces of the ceramic cover 11.

[0053] In addition, the ceramic component 1 also includes a sealing ring 14, which is brazed to the area around the gas passage 10 of the ceramic cover 11 to facilitate welding with the sealing sheet 4.

[0054] In step S4, the integrated connector is tightly fitted to the area surrounding the air passage 10 of the ceramic cover 11 through the sealing ring 8.

[0055] In step S6, the resistance welding device applies a thrust toward the ceramic cover 11 to the integrated joint, causing the resistance welding head 7 to push the sealing piece 4 against the sealing ring 14, while simultaneously compressing the bellows 6. Then, the resistance welding process is used to seal the sealing piece 4 and the sealing ring 14 to completely seal the gas passage 10.

[0056] Except for steps S1, S4 and S6 mentioned above, the remaining steps in this embodiment are the same as those in Embodiment 1.

[0057] Optionally, both the sealing plate 4 and the sealing ring 14 can be made of Kovar alloy.

[0058] In this embodiment, the gas passage 10 is set on the ceramic component 1. The ceramic component 1, the magnetic plate 2, and the iron core sleeve 3 are initially sealed by laser welding. Then, the sealing piece 4 is sealed and welded to the gas passage 10 by resistance welding, thus achieving the final sealing of the sealed cavity 20. This eliminates the exhaust pipe structure that relies on clamp sealing in the existing process, significantly reducing the product leakage rate and improving the long-term sealing performance of the sealed cavity 20. At the same time, resistance welding is only for small-area sealing pieces 4, eliminating the need for high-power equipment, reducing production costs and improving production efficiency. In addition, the integrated connector of the sealing equipment integrates the three functions of vacuuming, gas filling, and resistance welding, eliminating the need to transfer workpieces between different devices, reducing process changeover time. Furthermore, the resistance welding head 7 is coaxially designed with the gas extraction and gas filling channels, eliminating the need for additional workpiece position adjustments. The cavity environment control and sealing can be completed in a single process, further significantly improving production efficiency.

[0059] In addition, the present invention also provides a high-voltage DC contactor, comprising: a ceramic component 1, a magnetic plate 2, an iron core sleeve 3, and a sealing plate 4. The ceramic component 1, the magnetic plate 2, the iron core sleeve 3, and the sealing plate 4 are sealed together using the high-voltage DC contactor sealing process described in Embodiment 1 or Embodiment 2. This process can simultaneously achieve the characteristics of low leakage rate, high insulation, and strong structural stability. The combination of laser welding and resistance welding can reduce costs and process difficulty, ensure the sealing performance of the sealed cavity 20, effectively extend the service life of the internal components of the contactor, and reduce the risk of failure under high-voltage conditions.

[0060] The same or similar parts between the various embodiments in this specification can be referred to mutually. Each embodiment focuses on describing the differences from other embodiments.

[0061] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A sealing process for a high-voltage DC contactor, characterized in that, Includes the following steps: S1, provides a ceramic component (1), a magnetic plate (2), an iron core sleeve (3) and a sealing plate (4), wherein the ceramic component (1) or the magnetic plate (2) is provided with an air passage hole (10). S2, the ceramic component (1), the magnetic plate (2) and the iron core sleeve (3) are assembled in sequence and then laser welded to form a preliminary sealing assembly around the preset sealing cavity (20), and the air passage (10) leads to the sealing cavity (20). S3, the preliminary sealing assembly is transferred to the sealing equipment; wherein the sealing equipment includes a vacuuming device, an inflation device, a resistance welding device and an integrated joint, the integrated joint includes a multi-port fitting (5), a bellows (6) and a resistance welding head (7), the resistance welding head (7) is inserted into the multi-port fitting (5) and the bellows (6), and the multi-port fitting (5) is sealed to a sealing plate (701) at one end of the resistance welding head (7) through the bellows (6). S4, place the sealing piece (4) at the air passage hole (10) on the ceramic component (1) or the magnetic plate (2), and make the integrated connector fit with the surrounding area of ​​the air passage hole (10); at this time, the other end of the resistance welding head (7) is distributed opposite to the sealing piece (4), and leaves room for the sealing piece (4) to move. S5, the vacuuming device evacuates the sealed cavity (20) through the multi-port fitting (5); when the vacuum level inside the sealed cavity (20) reaches the preset requirement, the vacuuming device is turned off; the gas filling device fills the sealed cavity (20) with protective gas through the multi-port fitting (5); after the gas filling is completed, the gas filling device is turned off. S6, the resistance welding device pushes the sealing piece (4) against the ceramic component (1) or the magnetic plate (2) through the resistance welding head (7), and uses resistance welding process to weld the sealing piece (4) to completely seal the gas passage hole (10).

2. The high-voltage DC contactor sealing process according to claim 1, characterized in that, The ceramic component (1) includes a ceramic cover (11), a connecting ring (12) and two stationary contacts (13). The connecting ring (12) is brazed to the bottom of the ceramic cover (11), and the two stationary contacts (13) are brazed side by side to the top of the ceramic cover (11). In step S1, if the gas passage hole (10) is selected to be opened on the ceramic component (1), the gas passage hole (10) is located on the ceramic cover (11).

3. The high-voltage DC contactor sealing process according to claim 2, characterized in that, The ceramic component (1) also includes a sealing ring (14), which is brazed to the area around the air passage hole (10) of the ceramic cover (11); in step S6, under the push of the resistance welding head (7), the sealing piece (4) and the sealing ring (14) are attached and fixed and sealed by resistance welding.

4. The high-voltage DC contactor sealing process according to claim 2, characterized in that, In step S2, the connecting ring (12) is welded to the top surface of the magnetic plate (2), and the iron core sleeve (3) is welded to the bottom surface of the magnetic plate (2).

5. The high-voltage DC contactor sealing process according to claim 1, characterized in that, Both ends of the multi-port fitting (5) are open, and one end is welded to the bellows (6), while the other end is fixed with a sealing ring (8). In step S4, the integrated connector is tightly fitted to the area around the air passage hole (10) of the ceramic component (1) or the magnetic plate (2) through the sealing ring (8).

6. The high-voltage DC contactor sealing process according to claim 1, characterized in that, The multi-port fitting (5) has an air extraction port (501) and an air filling port (502) on its outer peripheral surface. The air extraction port (501) and the air filling port (502) are connected to the sealed cavity (20) through the internal cavity of the multi-port fitting (5) and the air passage hole (10). The vacuuming device is connected to the air extraction port (501), and the air filling device is connected to the air filling port (502).

7. The high-voltage DC contactor sealing process according to claim 1, characterized in that, The air passage hole (10) is opened on the magnetic plate (2), and the bottom surface of the magnetic plate (2) is provided with a receiving groove (201) around the air passage hole (10); in step S4, the sealing piece (4) is placed in the receiving groove (201) and blocked and limited by the resistance welding head (7).

8. The high-voltage DC contactor sealing process according to claim 7, characterized in that, The receiving groove (201) is provided with welding rings (202) distributed around the air passage hole (10); in step S6, the resistance welding device applies a thrust toward the magnetic plate (2) to the integrated connector, so that the resistance welding head (7) pushes the sealing piece (4) against the welding ring (202), and at the same time compresses the bellows (6). Then, the resistance welding process is used to seal the sealing piece (4) and the welding ring (202).

9. The high-voltage DC contactor sealing process according to claim 1, characterized in that, In step S6, the parameters of the resistance welding process are: welding current of 800~2000A, welding pressure of 10~50N, welding energizing time of 0.3~1.5s, and the diameter of the weld point after welding is 1~3mm.

10. A high-voltage DC contactor, characterized in that, include: The ceramic component (1), the magnetic plate (2), the iron core sleeve (3), and the sealing plate (4) are sealed together using the high-voltage DC contactor sealing process described in any one of claims 1 to 9.

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