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

Abstract

The application 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 conducting plate, an iron core sleeve and a sealing sheet, assembling, laser welding to form a primary sealing assembly, and transferring to a sealing device; placing the sealing sheet on the gas passage through hole on the ceramic assembly or the magnetic conducting plate, and making the integrated joint adhere to the peripheral area of the gas passage through hole; a vacuumizing device is used to vacuumize the sealing cavity through a multi-way pipe, and the vacuumizing device is closed after the vacuum degree reaches a preset requirement; a gas filling device is used to fill protective gas into the sealing cavity through the multi-way pipe; the gas filling device is closed after the gas filling is completed; a resistance welding device is used to push the sealing sheet to abut against the ceramic assembly or the magnetic conducting plate through a resistance welding joint, and the resistance welding process is used to weld the sealing sheet, so as to completely seal the gas passage through hole. The application can improve the production efficiency, reduce the cost and product leakage rate, and improve the long-term sealing property.

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:

[0004] 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.

[0005] 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 plates, ceramic components and core housings, resulting in a large welding area. In order to ensure the welding depth and sealing performance, high-power resistance welding equipment is needed, 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.

[0006] 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

[0007] 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.

[0008] 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:

[0009] S1, providing a ceramic assembly, a magnetic conducting plate, an iron core sleeve and a sealing piece, the ceramic assembly or the magnetic conducting plate is provided with an air passage through hole;

[0010] S2, sequentially assembling the ceramic assembly, the magnetic conducting plate and the iron core sleeve and then performing laser welding, so that the three form a preliminary sealing combination around a predetermined sealed cavity, and the air passage through hole leads to the sealed cavity;

[0011] 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 connected to the sealing plate at one end of the resistance welding joint through the corrugated pipe;

[0012] S4, placing the sealing piece at the air passage through hole on the ceramic assembly or the magnetic conducting plate, and making the integrated joint fit with the air passage through hole peripheral area; 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;

[0013] 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;

[0014] 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, so as to completely seal the air passage through hole.

[0015] 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 the two static contacts are brazed to the top of the ceramic cover side by side; in step S1, if the gas passage hole is selected to be opened on the ceramic assembly, the gas passage hole is located on the ceramic cover.

[0016] As a further improvement of the present application, the ceramic assembly further comprises a sealing ring, the sealing ring 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.

[0017] As a further improvement of the present application, in step S2, the connecting ring is welded to the top surface of the magnetic conductive plate, and the core sleeve is welded to the bottom surface of the magnetic conductive plate.

[0018] As a further improvement of the present application, the multi-pass pipe is open at both axial ends, and one end is 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 conductive plate through the sealing ring.

[0019] As a further improvement of the present application, the outer peripheral surface of the multi-pass pipe is provided with a gas extraction port and a gas filling port, the gas extraction port and the gas filling port 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.

[0020] As a further improvement of the present application, the gas passage hole is opened on the magnetic conductive plate, and the bottom surface of the magnetic conductive 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.

[0021] As a further improvement of the present 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 in the direction of the magnetic conductive plate, so that the resistance welding head pushes the sealing sheet to abut 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.

[0022] As a further improvement of the present 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.

[0023] The application also provides a high-voltage direct-current contactor, comprising a ceramic assembly, a magnetic conductive plate, a core sleeve and a sealing sheet, wherein the ceramic assembly, the magnetic conductive plate, the core sleeve and the sealing sheet are sealed and connected by using the high-voltage direct-current contactor sealing process as described above.

[0024] The application has the following beneficial effects: the application provides a high-voltage direct-current contactor sealing process and a high-voltage direct-current contactor, the preliminary sealing of the ceramic assembly, the magnetic conductive plate and the core sleeve is realized by laser welding, and then the sealing sheet is sealed and welded on the gas passage hole by the resistance welding process to realize the final sealing of the sealed cavity, thereby significantly reducing the product leakage rate and improving the long-term sealing performance of the sealed cavity; at the same time, the resistance welding is only for a small-area sealing sheet, and a high-power device is not needed, thereby reducing the production cost and improving the production efficiency; in addition, the integrated joint of the sealing device realizes the three functions of vacuumizing, gas filling and resistance welding, the workpiece does not need to be transferred between different devices, the process switching time is reduced, the workpiece position does not need to be adjusted additionally, the cavity environment regulation and sealing can be completed in a single process, and the production efficiency is further greatly improved; further, the integrated joint is closely attached to the peripheral area of the gas passage hole of the magnetic conductive plate through the sealing ring, a flexible sealing is formed, air leakage in the vacuumizing and gas filling process is avoided, the cavity vacuum degree and the purity of the protective gas are ensured, 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, a high-precision adjustment device is not needed for alignment, and the device debugging difficulty is reduced. BRIEF DESCRIPTION OF DRAWINGS

[0025] 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 also be obtained without creative labor on the basis of these drawings.

[0026] Figure 1 The step block diagram of the high-voltage direct-current contactor sealing process of the application;

[0027] Figure 2 The perspective view of the high-voltage direct-current contactor and the integrated joint of the first embodiment of the application;

[0028] Figure 3 The cross-sectional view of the high-voltage direct-current contactor and the integrated joint of the first embodiment of the application;

[0029] Figure 4 The perspective view of the high-voltage direct-current contactor after the sealing of the first embodiment of the application is completed;

[0030] Figure 5 The cross-sectional view of the high-voltage direct-current contactor and the integrated joint of the second embodiment of the application;

[0031] Figure 6 Figure 2 is a perspective view of the high-voltage DC contactor after sealing of the embodiment two of the present application.

[0032] The following description will be made in conjunction with the drawings:

[0033] 1, ceramic assembly; 11, ceramic cover; 12, connecting ring; 13, static contact; 14, sealing ring; 2, magnetic conductive plate; 201, accommodating groove; 202, welding ring; 3, core sleeve; 4, sealing piece; 5, multi-way pipe fitting; 501, air outlet; 502, air inlet; 6, corrugated pipe; 7, resistance welding head; 701, sealing plate; 8, sealing ring; 10, air passage hole; 20, sealed cavity. DETAILED DESCRIPTION

[0034] The above embodiments are only some of the embodiments of the present application, and are not all the embodiments of the present application. The present application can also be implemented or applied through other different specific embodiments, and the details in the specification can be modified or changed based on different views and applications without departing from the spirit of the present application. It should be noted that the following embodiments and features in the embodiments can be combined with each other without conflict. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor are within the scope of protection of the present application.

[0035] It should be noted that the various aspects described below are within the scope of the appended claims. It should be apparent that the aspects described herein can be embodied in a wide variety of forms and that any specific structure and / or function described herein is merely illustrative. Based on the teachings provided herein one skilled in the art will appreciate that one or more aspects described herein can be implemented independently of any other aspects and that non-dependent aspects can be implemented in conjunction with each other in any way. For example, a variety of apparatus can be implemented using any number and combination of the aspects described herein. Additionally, this apparatus and / or method can be implemented using other structure and / or functionality in addition to or other than one or more of the aspects described herein.

[0036] It should also be noted that the drawings included in the following embodiments are only schematic and that the sizes of the components shown in the drawings can not bear any relation to the actual sizes of the components they represent. Embodiments of the present application can be implemented in any of the following forms, but not limited to these forms.

[0037] Also in the following description, specific details are given to provide thorough understanding of examples. However, one skilled in the relevant art will understand that the examples can be practiced without these specific details.

[0038] The technical solutions provided by the embodiments of the present application are described below with reference to the drawings. Embodiment one

[0039] Referring to Figures 1 to 4 The present application provides a high-voltage DC contactor sealing process, comprising the following steps S1-S6.

[0040] S1, providing a ceramic assembly 1, a magnetic conductive plate 2, a core sleeve 3 and a sealing sheet 4; wherein the magnetic conductive plate 2 has a gas passage hole 10 formed in advance, the gas passage hole 10 extends along the thickness direction of the magnetic conductive plate 2, and penetrates the top surface and the bottom surface of the magnetic conductive plate 2. The gas passage hole 10 serves as a channel for communicating the sealed cavity 20, for vacuum pumping and gas charging operations.

[0041] S2, sequentially assembling the ceramic assembly 1, the magnetic conductive plate 2 and the core sleeve 3, and then laser welding to form a preliminary sealing assembly around the predetermined sealed cavity 20, and the gas passage hole 10 on the magnetic conductive plate 2 leads to the sealed cavity 20.

[0042] S3, transferring the preliminary sealing assembly to a sealing device.

[0043] In the present application, the sealing device comprises a vacuum pumping device, a gas charging device, a resistance welding device and an integrated joint. The integrated joint comprises a multi-way pipe fitting 5, a corrugated pipe 6 and a resistance welding joint 7, the resistance welding joint 7 is arranged in the multi-way pipe fitting 5 and the corrugated pipe 6, and one end of the resistance welding joint 7 is provided with a sealing plate 701, and the multi-way pipe fitting 5 is sealed and connected to the sealing plate 701 through the corrugated pipe 6.

[0044] S4, placing the sealing sheet 4 at the gas passage hole 10 on the ceramic assembly 1 or the magnetic conductive plate 2, and tightly fitting the integrated joint with the peripheral area of the gas passage hole 10; at this time, the other end of the resistance welding joint 7 is distributed opposite to the sealing sheet 4, and there is a moving space for the sealing sheet 4, so that there is a gap between the sealing sheet 4 and the magnetic conductive plate 2, which does not block the gas passage hole 10, ensuring the subsequent vacuum pumping and gas charging operations.

[0045] S5, the vacuum pumping device pumps the sealed cavity 20 through the gas passage hole 10 via the multi-way pipe fitting 5; when the internal vacuum degree of the sealed cavity 20 reaches the predetermined requirement, the vacuum pumping device is closed; then, the gas charging device charges the sealed cavity 20 with protective gas through the gas passage hole 10 via the multi-way pipe fitting 5; after the gas charging is completed and the internal protective gas pressure of the sealed cavity 20 is stable, the gas charging device is closed.

[0046] S6, the resistance welding device pushes the sealing sheet 4 to abut against the magnetic conductive plate 2 through the resistance welding head 7, and adopts the resistance welding process to weld the sealing sheet 4, so as to completely seal the gas path through hole 10.

[0047] The present application firstly realizes the preliminary sealing of the ceramic assembly 1, the magnetic conductive plate 2 and the core sleeve 3 through laser welding, and then realizes the final sealing of the sealed cavity 20 by sealing and welding the sealing sheet 4 in the gas path through hole 10 through the resistance welding process, cancels the exhaust pipe structure depending on the jaw sealing in the existing process, significantly reduces the product leakage rate, and improves the long-term sealing performance of the sealed cavity 20; at the same time, the resistance welding is only for the small-area sealing sheet 4, without the need of high-power equipment, which reduces the production cost and improves the production efficiency; in addition, the integrated joint of the sealing equipment realizes the three functions of vacuumizing, air charging and resistance welding, without the need of transferring the workpiece between different equipment, reduces the process switching time, and the resistance welding head 7 is coaxial with the air exhaust and air charging channels, without the need of additional adjustment of the workpiece position, so that the cavity environment regulation and sealing can be completed in a single process, and the production efficiency is further greatly improved.

[0048] As shown in Figure 3 The ceramic assembly 1 in the present application includes a ceramic cover 11, a connecting ring 12 and two static contacts 13, the connecting ring 12 is brazed to the bottom of the ceramic cover 11, and the two static contacts 13 are brazed side by side to the top of the ceramic cover 11.

[0049] In the embodiment, the bottom of the connecting ring 12 is provided with a first outward turned edge around the circumference; the core sleeve 3 is a circular cup shape with a bottom and no top, and the top is provided with a second outward turned edge around the circumference along the port.

[0050] In step S2, the whole circumference of the first outward turned edge of the connecting ring 12 is laser welded to the top surface of the magnetic conductive plate 2, and the whole circumference of the second outward turned edge of the core sleeve 3 is laser welded to the bottom surface of the magnetic conductive plate 2, so as to form a preliminary sealing combination, and the laser welding process has narrow welding seam, high efficiency and stable structure.

[0051] In the present application, the welding sequence of the ceramic assembly 1, the magnetic conductive plate 2 and the core sleeve 3 is arbitrary and not required.

[0052] It can be understood that the high-voltage DC contactor also includes a moving contact, a push rod part and an iron core part inside the sealed cavity 20, and these parts need to be installed on the magnetic conductive plate 2 before laser welding in step S2, and then laser welding can be performed.

[0053] Referring to Figure 3 The multi-way pipe fitting 5 in the embodiment is specifically a four-way pipe fitting, the axial two ends of the multi-way pipe fitting 5 are provided with openings, and one end is welded with the corrugated pipe 6, and the other end is fixed with a sealing ring 8. The sealing connection of the corrugated pipe 6 with the multi-way pipe fitting 5 and the resistance welding head 7 can prevent external air from entering, and further ensure the accuracy of the cavity environment regulation.

[0054] In step S4, the integrated joint is tightly attached to the peripheral area of the gas passage hole 10 of the magnetic conducting plate 2 through the sealing ring 8 to form a flexible seal, so as to avoid air leakage during the vacuumizing and gas filling process and ensure the vacuum degree of the cavity and the purity of the protective gas. Meanwhile, the elastic property of the bellows 6 can compensate for the coaxiality error and height deviation between the integrated joint and the magnetic conducting plate 2, so that the high-precision adjustment equipment is not required for alignment, and the equipment debugging difficulty is reduced.

[0055] The outer peripheral surface of the multi-way pipe fitting 5 is provided with a gas suction port 501 and a gas filling port 502, and the gas suction port 501 and the gas filling port 502 are connected to the sealed cavity 20 through the internal cavity of the multi-way pipe fitting 5 and the gas passage hole 10. The vacuumizing device is connected to the gas suction port 501, and the gas filling device is connected to the gas filling port 502.

[0056] In step S5, after the vacuumizing device completes the vacuumizing, the vacuumizing pipeline is closed through the electromagnetic valve; similarly, after the gas filling device completes the gas filling, the gas filling pipeline is closed through the electromagnetic valve, so as to ensure the sealing of the inside of the integrated joint and the inside of the sealed cavity 20 and prevent air from entering and the protective gas from overflowing.

[0057] Of course, in other embodiments of the present application, the multi-way pipe fitting 5 can also be a three-way pipe fitting, that is, the gas suction port 501 and the gas filling port 502 share one through hole, and the vacuumizing pipeline and the gas filling pipeline can be opened and closed through the logical control of the electromagnetic valve, which is a conventional technology and does not need to be improved, so it will not be described in detail.

[0058] It should be noted that the vacuumizing device for realizing the vacuumizing operation of the sealed cavity 20 and the gas filling device for filling the protective gas into the sealed cavity 20 both adopt conventional equipment structures and models known to those skilled in the art, and do not involve improvements to the structure of such equipment itself.

[0059] Optionally, the protective gas filled into the sealed cavity 20 can be one of nitrogen, argon or helium, or a mixed gas formed by mixing the above-mentioned gases in any proportion.

[0060] Continuing to refer to Figure 3 The bottom surface of the magnetic conducting plate 2 is provided with a containing groove 201 around the gas passage hole 10, and the diameter of the containing groove 201 is slightly larger than that of the sealing sheet 4. In step S4, the sealing sheet 4 is placed in the containing groove 201 and is blocked and limited by the resistance welding head 7. The containing groove 201 on the bottom surface of the magnetic conducting plate 2 can directly pre-position the sealing sheet 4, and the sealing sheet 4 can be kept stable after being placed in the containing groove 201. Meanwhile, the blocking and limiting effect of the resistance welding head 7 can prevent the sealing sheet 4 from being displaced or falling off during the vacuumizing and gas filling process, thereby improving the process stability.

[0061] It is worth mentioning that the accommodating groove 201 is provided with a welding ring 202 distributed around the gas passage hole 10. In step S6, the resistance welding device applies a pushing force to the integrated joint in the direction of the magnetic conductive plate 2, so that the resistance welding head 7 pushes the sealing sheet 4 to abut against the welding ring 202, and at the same time, the bellows 6 is compressed, and then the sealing sheet 4 and the welding ring 202 are sealed and welded by the resistance welding process. The welding ring 202 in the accommodating groove 201 is distributed around the gas passage hole 10, which provides an annular welding position for the sealing sheet 4, and compared with planar welding, a continuous sealing weld can be formed to completely block the communication between the gas passage hole 10 and the outside.

[0062] In the resistance welding device, a welding head driving device, such as a pneumatic cylinder, is connected to the integrated joint to push the sealing sheet 4 to abut against the welding ring 202 by the resistance welding head 7 in step S6.

[0063] In step S6, the resistance welding head 7 is electrically connected to the positive electrode of the resistance welding device, and the magnetic conductive plate 2 is electrically connected to the negative electrode of the resistance welding device to perform the resistance welding operation. 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 current time is 0.3-1.5 s, and the diameter of the welding spot after welding is 1-3 mm. The resistance welding process parameters can ensure that the sealing sheet 4 and the magnetic conductive plate 2 form an effective sealing connection, while avoiding excessive pressure causing the sealing sheet 4 to deform or insufficient pressure causing poor welding. Example Two

[0064] The difference between this embodiment and example one is that the gas passage hole 10 is arranged on the ceramic assembly 1.

[0065] Specifically, referring to Figure 5 and Figure 6 In the ceramic assembly 1 provided in step S1, the top of the ceramic cover 11 is previously provided with a gas passage hole 10 extending in the vertical direction and penetrating through the top surface and the bottom surface of the ceramic cover 11.

[0066] In addition, the ceramic assembly 1 further comprises a sealing ring 14 which is brazed to the peripheral area of the gas passage hole 10 of the ceramic cover 11 to facilitate welding with the sealing sheet 4.

[0067] In step S4, the integrated joint is tightly attached to the peripheral area of the gas passage hole 10 of the ceramic cover 11 through the sealing ring 8.

[0068] In step S6, the resistance welding device applies a pushing force to the integrated joint in the direction of the ceramic cover 11, so that the resistance welding head 7 pushes the sealing sheet 4 to abut against the sealing ring 14, and at the same time, the bellows 6 is compressed, and then the sealing sheet 4 and the sealing ring 14 are sealed and welded by the resistance welding process to completely seal the gas passage hole 10.

[0069] In addition to the steps S1, S4 and S6, the remaining steps of the embodiment are the same as those of the first embodiment.

[0070] Optionally, the sealing sheet 4 and the sealing ring 14 can be made of Kovar alloy.

[0071] In the embodiment, the gas passage hole 10 is arranged on the ceramic assembly 1, and the preliminary sealing of the ceramic assembly 1, the magnetic conductive plate 2 and the core sleeve 3 is realized by laser welding, and then the sealing sheet 4 is sealingly welded to the gas passage hole 10 by resistance welding to realize the final sealing of the sealed cavity 20, cancel the exhaust pipe structure relying on the sealing of the existing process, significantly reduce the product leakage rate, and improve the long-term sealing performance of the sealed cavity 20. At the same time, the resistance welding is only for the small-area sealing sheet 4, without the need for high-power equipment, which reduces the production cost and improves the production efficiency. In addition, the integrated joint of the sealing equipment realizes the functions of vacuumizing, air charging and resistance welding, and the workpiece does not need to be transferred between different equipment, the process switching time is reduced, and the resistance welding joint 7 is coaxially designed with the air exhaust and air charging channels, without the need for additional adjustment of the workpiece position. The cavity environment regulation and sealing can be completed in a single process, and the production efficiency is further greatly improved.

[0072] In addition, the application further provides a high-voltage DC contactor, which comprises a ceramic assembly 1, a magnetic conductive plate 2, a core sleeve 3 and a sealing sheet 4. The ceramic assembly 1, the magnetic conductive plate 2, the core sleeve 3 and the sealing sheet 4 are sealingly connected by the high-voltage DC contactor sealing process as described in the first embodiment or the second embodiment, and can simultaneously have the characteristics of low leakage rate, high insulation and strong structural stability. The combination of laser welding and resistance welding can reduce the cost and process difficulty, ensure the sealing performance of the sealed cavity 20, effectively prolong the service life of the internal components of the contactor, and reduce the risk of failure under high-voltage working conditions.

[0073] In the specification, the same or similar parts among the various embodiments can be referred to each other, and each embodiment focuses on the difference from other embodiments.

[0074] The above is only a specific implementation of the application, but the protection scope of the application is not limited thereto. Any changes or replacements within the technical range disclosed in the application can be easily thought of by those skilled in the art, and should be covered within the protection scope of the application. Therefore, the protection scope of the application should be subject to the protection scope of the claims.

Claims

1. A high voltage DC contactor sealing process, characterized by, The method comprises the following steps: S1, providing a ceramic assembly (1), a magnetic conducting plate (2), a core sleeve (3) and a sealing sheet (4), the ceramic assembly (1) or the magnetic conducting plate (2) is provided with a gas passage hole (10); S2, sequentially assembling the ceramic assembly (1), the magnetic conducting plate (2) and the core sleeve (3) and then performing laser welding, so that the three form a preliminary sealing assembly around a preset sealed cavity (20), the gas passage hole (10) is open to the sealed cavity (20); S3, transferring the preliminary sealing assembly to a sealing device; wherein the sealing device comprises a vacuumizing device, a gas filling device, a resistance welding device and an integrated joint, the integrated joint comprises a multi-pass pipe fitting (5), a corrugated pipe (6) and a resistance welding joint (7), the resistance welding joint (7) is arranged in the multi-pass pipe fitting (5) and the corrugated pipe (6), and the multi-pass pipe fitting (5) is sealingly connected to a sealing plate (701) at one end of the resistance welding joint (7) through the corrugated pipe (6); S4, placing the sealing sheet (4) at the gas passage hole (10) on the ceramic assembly (1) or the magnetic conducting plate (2), and making the integrated joint fit with the peripheral area of the gas passage hole (10); at this time, the other end of the resistance welding joint (7) is distributed opposite to the sealing sheet (4), and a moving space is left for the sealing sheet (4); S5, the vacuumizing device performs vacuumizing on the sealed cavity (20) through the multi-pass pipe fitting (5); when the vacuum degree inside the sealed cavity (20) reaches a preset requirement, the vacuumizing device is closed; the gas filling device fills protective gas into the sealed cavity (20) through the multi-pass pipe fitting (5); after the gas filling is completed, the gas filling device is closed; S6, the resistance welding device pushes the sealing sheet (4) to abut against the ceramic assembly (1) or the magnetic conducting plate (2) through the resistance welding joint (7), and performs welding on the sealing sheet (4) by using a resistance welding process, so as to completely seal the gas passage hole (10); wherein the axial two ends of the multi-pass pipe fitting (5) are open, and one end is welded with the corrugated pipe (6) and the other end is fixed with a sealing ring (8); in step S4, the integrated joint is tightly fitted with the peripheral area of the gas passage hole (10) of the ceramic assembly (1) or the magnetic conducting plate (2) through the sealing ring (8); the outer peripheral surface of the multi-pass pipe fitting (5) is provided with a gas suction port (501) and a gas filling port (502), the gas suction port (501) and the gas filling port (502) are connected with the sealed cavity (20) through the internal cavity of the multi-pass pipe fitting (5) and the gas passage hole (10); the vacuumizing device is connected with the gas suction port (501), and the gas filling device is connected with the gas filling port (502).

2. The HVDC contactor sealing process of claim 1, wherein, The ceramic assembly (1) comprises a ceramic cover (11), a connecting ring (12) and two static contacts (13), the connecting ring (12) is brazed at the bottom of the ceramic cover (11), and the two static contacts (13) are brazed at the top of the ceramic cover (11); in step S1, if the gas passage hole (10) is selected to be opened on the ceramic assembly (1), the gas passage hole (10) is located on the ceramic cover (11).

3. The HVDC contactor sealing process of claim 2, wherein, The ceramic assembly (1) further comprises a sealing ring (14), the sealing ring (14) is brazed at the peripheral area of the gas passage hole (10) of the ceramic cover (11); in step S6, the sealing sheet (4) is attached to the sealing ring (14) and is fixedly connected in a resistance welding manner under the pushing of the resistance welding head (7).

4. The HVDC contactor sealing process of claim 2, wherein, In step S2, the connecting ring (12) is welded to the top surface of the magnetic conducting plate (2), and the iron core sleeve (3) is welded to the bottom surface of the magnetic conducting plate (2).

5. The HVDC contactor sealing process of claim 1, wherein, The gas passage hole (10) is opened on the magnetic conducting plate (2), and the bottom surface of the magnetic conducting plate (2) is provided with a receiving groove (201) around the gas passage hole (10); in step S4, the sealing sheet (4) is placed in the receiving groove (201) and is blocked by the resistance welding head (7).

6. The HVDC contactor sealing process of claim 5, wherein, The receiving groove (201) is provided with a welding ring (202) distributed around the gas passage hole (10); in step S6, the resistance welding device applies a pushing force to the integrated joint in the direction of the magnetic conducting plate (2), so that the resistance welding head (7) pushes the sealing sheet (4) to abut against the welding ring (202), and at the same time, the bellows (6) is compressed, and then the sealing sheet (4) and the welding ring (202) are sealed and welded by resistance welding process.

7. The HVDC contactor sealing process of claim 1, wherein, In step S6, the parameters of the resistance welding process are as follows: the welding current is 800-2000A, the welding pressure is 10-50N, the welding power-on time is 0.3-1.5s, and the diameter of the welding spot after welding is 1-3mm.

8. A high voltage DC contactor, characterized by Comprise: A ceramic assembly (1), a magnetic conducting plate (2), an iron core sleeve (3) and a sealing sheet (4), the ceramic assembly (1), the magnetic conducting plate (2), the iron core sleeve (3) and the sealing sheet (4) are sealed and connected by the high-voltage direct-current contactor sealing process according to any one of claims 1 to 7.

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