Brazing tool, brazing method, and brazing quality detection method

Abstract

The application relates to a brazing tool, a brazing method and a brazing quality detection method, and belongs to the technical field of welding. The brazing tool comprises an electric connector mounting plate configured to mount and place an electric connector; an induction heating device configured to heat the electric connector, a coil strand assembled to the electric connector and brazing filler; a first clamping mechanism configured to clamp the coil strand; and a second clamping mechanism configured to enable the induction heating device to closely contact the electric connector. The brazing tool is used for assembling the coil strand to the electric connector, assembling the electric connector to the electric connector mounting plate, closely arranging the induction heating device to the electric connector, clamping the coil strand by the first clamping mechanism, clamping the induction heating device by the second clamping mechanism, then melting the brazing filler by utilizing the low melting point of the brazing filler, realizing brazing welding, and timely adjusting the clamping state of the first clamping mechanism and the second clamping mechanism to discharge air between the strands and shape the brazing product, thereby improving the brazing quality.

Description

Technical Field

[0001] This application relates to the field of brazing technology, and in particular to a brazing fixture, a brazing method, and a brazing quality inspection method. Background Technology

[0002] In existing technologies, the variable-speed pumped-storage rotor bar coil differs significantly in structural design from the bar coil of traditional pumped-storage generator motors. Its winding end electrical connectors feature a double-sided tight-fit structure, requiring not only that the electrical connectors be welded to the coil end strands into a single unit, but also that the brazing quality be high, ensuring a certain length of strands behind the electrical connectors is welded together to improve the overall rigidity and strength of the coil end. Therefore, a new brazing fixture and / or brazing method needs to be designed. Summary of the Invention

[0003] This application provides a brazing fixture to at least partially solve the above-mentioned technical problems.

[0004] To achieve the above objectives, according to a first aspect of this application, this application provides a brazing fixture, comprising: An electrical connector mounting plate is configured for mounting and placing electrical connectors. An induction heating device is configured to heat the electrical connector and the coil strands and brazing filler metal assembled to the electrical connector; A first clamping mechanism is configured to clamp the coil strands; The second clamping mechanism is configured to cause the induction heating device to make tight contact with the electrical connector.

[0005] Optionally, the electrical connector includes an integrally formed strand connection portion and a conductor portion. The outer peripheral dimension of the strand connection portion is larger than the outer peripheral dimension of the conductor portion. The electrical connector mounting plate has a through hole for the conductor portion to pass through, and the electrical connector mounting plate is used to support the strand connection portion.

[0006] Optionally, the induction heating device includes an induction coil frame on which a heating induction coil is disposed; The heating induction coil includes: A front-end coil is used to heat the welded section of the coil strands located outside the electrical connector; The rear coil is used to heat the connection section where the coil strands extend into the electrical connector; wherein both the front coil and the rear coil are made of magnetic material.

[0007] Optionally, the second clamping mechanism includes a crossbar with a vertical screw threaded through it, and an upper pressure plate for pressing the coil strands is provided at the lower end of the vertical screw; wherein, a first rotating handle is provided at the upper end of the vertical screw.

[0008] Optionally, the first clamping mechanism includes two vertical rods, which are respectively connected to the two ends of the horizontal rod; a transverse screw is threaded through the vertical rod, and a side pressure plate is provided at the end of the transverse screw near the induction heating device; wherein, a second rotating handle is provided at the end of the transverse screw away from the induction heating device; wherein, a guide light rod that freely passes through the vertical rod is connected to the side pressure plate.

[0009] Optionally, the lower end of the vertical rod is connected to a support plate for supporting the electrical connector mounting plate.

[0010] Optionally, the vertical bar is hinged to the horizontal bar.

[0011] According to a second aspect of this application, a brazing method is provided, employing the aforementioned brazing fixture, comprising: The brazing fixture is assembled into place, the electrical connector is installed and fixed, and the coil strands and brazing filler metal are assembled. Organize the coil strands and the brazing filler metal; Start the induction heating device and adjust the first and second clamping mechanisms in a timely manner according to the melting state of the brazing filler metal to obtain the brazed workpiece.

[0012] Optionally, assembling the coil strands and the solder includes: using a forming block to bulge the cavity of the electrical connector from the opening end of the strand mounting slot of the electrical connector; inserting the coil strands into the bulged cavity; and inserting the solder between the coil strands and the cavity wall.

[0013] Optionally, the method of straightening the coil strands and the solder includes: clamping and fixing the coil strands in the strand mounting groove, wherein the coil strands include a section to be cut extending out of the strand mounting groove; cutting the section to be cut close to the electrical connector and making its cross-section flat; wherein each coil strand is free from collapsed edges, curling, crossing, and misalignment.

[0014] According to a third aspect of this application, a brazing quality inspection method is provided, which inspects the brazed product obtained by the above-described brazing method, including... Determine the baseline for the flaw detection sensitivity of the UT flaw detector; The UT flaw detector is used to examine the brazed joint area and obtain the flaw detection reflection signal; The flaw detection reflection signal is compared with the flaw detection sensitivity benchmark to obtain the flaw detection result.

[0015] Optionally, determining the flaw detection sensitivity benchmark of the UT flaw detector includes scanning the unbrazed electrical connector with a single-crystal straight probe to find the bottom reflection echo; adjusting the first bottom reflection echo to 80% of the height of the UT flaw detector screen; adjusting the scanning range and continuing to repeat the steps of finding the bottom reflection echo; adjusting the fifth bottom reflection echo to be displayed on the UT flaw detector screen so that the first to fifth bottom reflection echoes can be displayed on the UT flaw detector screen; and increasing the gain by 12dB as the flaw detection sensitivity benchmark. The step of using the UT flaw detector to inspect the brazed joint area and obtain the flaw detection reflection signal includes: uniformly applying coupling agent to the flaw detection surface of the electrical connector; moving the probe of the UT flaw detector in the brazed joint area of ​​the electrical connector with the adjusted flaw detection sensitivity reference to detect suspicious reflection signals; wherein, the overlap width of the probe of the UT flaw detector during the inspection is not less than 15% of the probe chip size; The step of comparing the flaw detection reflection signal with the flaw detection sensitivity benchmark to obtain the flaw detection result includes: when the reflected echo generated by the brazed joint area reaches or exceeds the amplitude height of the flaw detection sensitivity benchmark, it is considered to be a brazed defect area; wherein, when a brazed defect area with a sensitivity greater than the benchmark is detected in the brazed joint area, the reflected echo of the brazed defect area is reduced to 40% of the screen height as the defect boundary point of the defect area, and the area enclosed by all boundary points is the brazed defect area.

[0016] The brazing fixture of this application embodiment, through the cooperation of an electrical connector mounting plate, an induction heating device, a first clamping mechanism, and a second clamping mechanism, assembles the coil strands onto the electrical connector during brazing, assembles the electrical connector onto the electrical connector mounting plate, positions the induction heating device tightly against the electrical connector, clamps the coil strands with the first clamping mechanism, and clamps the induction heating device with the second clamping mechanism. Then, taking advantage of the low melting point of the brazing filler metal, the filler metal is melted to achieve brazing. The first and second clamping mechanisms adjust the clamping state in a timely manner to discharge brazing exhaust gas and shape the brazed product, thereby improving the brazing quality.

[0017] Other features and advantages of this application will be described in detail in the following detailed description section. Attached Figure Description To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] To gain a more complete understanding of this application and its beneficial effects, the following description will be provided in conjunction with the accompanying drawings, wherein the same reference numerals in the following description denote the same parts.

[0019] Figure 1 This is a schematic diagram of a brazing fixture assembled with coil strands and electrical connectors according to an exemplary embodiment of this disclosure; Figure 2 This is a schematic diagram of the induction heating device in an exemplary embodiment of the present disclosure from a first perspective. Figure 3 This is a schematic diagram of the induction heating device in an exemplary embodiment of the present disclosure from a second perspective. Figure 4 This is a schematic diagram of a structure for connecting an electrical connector to coil strands in an exemplary embodiment of this disclosure; Figure 5 This is a schematic diagram of the structure of an electrical connector in an exemplary embodiment of this disclosure; Figure 6 This is a waveform diagram illustrating how a UT flaw detector determines a brazing defect area in an exemplary embodiment of this disclosure.

[0020] Figure label: 1. Support plate, 2. Vertical rod, 3. Horizontal rod, 4. Electrical connector, 5. Electrical connector mounting plate, 6. Upper pressure plate, 7. Vertical screw, 8. First rotating handle, 9. Induction heating device, 10. Side pressure plate, 11. Horizontal screw, 12. Second rotating handle, 13. Guide light rod, 14. Side brazing filler metal, 15. Coil strands, 16. Middle brazing filler metal, 17. Coil frame, 18. Front coil, 19. Rear coil, 20. Sealing section. Detailed Implementation

[0021] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of this application without creative effort are within the protection scope of this application.

[0022] In some embodiments, refer to Figure 1This application provides a brazing fixture, including: an electrical connector mounting plate 5 configured for mounting and placing an electrical connector 4; an induction heating device 9 configured to heat the electrical connector 4, as well as coil strands 15 and brazing filler metal assembled to the electrical connector 4; a first clamping mechanism configured to clamp the coil strands 15, ensuring a tight and reliable brazing between the coil strands 15 and the electrical connector 4; and a second clamping mechanism configured to ensure close contact between the heating device and the electrical connector 4, thereby improving brazing efficiency. The brazing fixture of this embodiment, through the cooperation of the electrical connector mounting plate 5, the induction heating device 9, the first clamping mechanism, and the second clamping mechanism, assembles the coil strand 15 onto the electrical connector 4 during brazing, assembles the electrical connector 4 onto the electrical connector mounting plate 5, positions the induction heating device 9 tightly against the electrical connector 4, clamps the coil strand 15 with the first clamping mechanism, clamps the induction heating device 9 with the second clamping mechanism, and then energizes the induction heating device 9 to heat the electrical connector 4, the coil strand 15, and the brazing filler metal. Utilizing the low melting point of the brazing filler metal, the filler metal is melted, achieving brazing welding. The first and second clamping mechanisms adjust the clamping state in a timely manner to discharge brazing exhaust gas and shape the brazed product, thereby improving the brazing quality.

[0023] The rotor coil ends of a variable-speed pumped-storage unit experience complex forces. The brazed coil connectors must meet both conductivity requirements and mechanical performance requirements under complex alternating loads. To ensure the brazing quality of connector 4 and coil strands 15 while facilitating assembly of coil strands 15 and connector 4 with pre-applied solder, the opening size of connector 4 needs precise setting. Assuming the theoretical width of the double-row coil strands 15 after stripping is A, the opening width of connector 4 is A+X, where X is slightly smaller than the total solder thickness. Generally, X being slightly smaller than the total solder thickness is within the range of 0.1-0.5 mm. For example, an intermediate solder 16 is pre-applied between the double-row coil strands 15, and side solder 14 is pre-applied between the sides of the coil strands 15 and the inner wall of connector 4. The thicknesses of the intermediate solder 16 and the side solder 14 are generally different; since the intermediate solder 16 has a wider diffusion range, its thickness is generally thicker than the side solder 14. For example, the thickness of the side brazing filler metal 14 is 0.2mm, and the thickness of the middle brazing filler metal 16 is 0.4mm. The opening size of the electrical connector 4 can be 0.6mm larger than the theoretical value of the double-strand wire, i.e., X=0.6mm, slightly smaller than the total thickness of the brazing filler metal 0.2mm+0.4mm+0.2mm=0.8mm. It should be noted that during assembly, only the opening of the electrical connector 4 needs to be expanded. After assembling the coil strands 15, the middle brazing filler metal 16, and the side brazing filler metal 14, a tight fit is achieved. Under the action of the second clamping mechanism, the opening of the electrical connector 4 gradually contracts and returns to its original position. Under the action of the induction heating device 9, the middle brazing filler metal 16 and the side brazing filler metal 14 melt and braze fully and with high quality.

[0024] In some embodiments, refer to Figure 1 , Figure 4 , Figure 5 The electrical connector 4 includes an integrally formed strand connection part and a conductor part. The outer circumference of the strand connection part is larger than that of the conductor part. The electrical connector mounting plate 5 has a through hole for the conductor part to pass through. The electrical connector mounting plate 5 supports the strand connection part. During assembly, the conductor part of the electrical connector 4 freely passes through the through hole, allowing the strand connection part to be located on the end face of the electrical connector mounting plate 5, thus achieving the installation of the electrical connector 4. It is worth noting that the size of the through hole is generally slightly larger than the size of the conductor part (generally, the length and width of the through hole are 0.1-0.5 mm larger than the length and width of the conductor part). This can reduce the wobbling displacement of the electrical connector 4 and improve the brazing quality while ensuring that the conductor part can pass through.

[0025] In some embodiments, refer to Figure 1 , Figure 2 , Figure 3 , Figure 4 The induction heating device 9 includes a coil frame 17 on which a heating induction coil is wound.

[0026] The heating induction coil includes: a front coil 18 for heating the sealing section 20 of the coil strands 15 located outside the electrical connector 4; and a rear coil 19 for heating the connection section of the coil strands 15 extending into the electrical connector 4. Both the front coil 18 and the rear coil 19 are made of magnetic material. It should be noted that, in the design, the front coil 18 and the rear coil 19 are designed with different magnetic field sizes to ensure uniform temperature rise in the heated area. The uniform heating of the connection area between the electrical connector 4 and the coil strands 15 is ensured by a reasonable side length of the induction heating device 9 branch (generally, the side length of the induction heating device 9 branch is 5-10 mm larger than the cross-sectional width of the coil strands 15), thereby achieving a single mounting and overall brazing of the electrical connector 4 and a certain length of strands (i.e., the sealing section 20).

[0027] In some embodiments, refer to Figure 1 The second clamping mechanism includes a crossbar 3, through which a vertical screw 7 is threaded. An upper pressure plate 6 for clamping the coil strands 15 is located at the lower end of the vertical screw 7. After the coil strands 15 are assembled to the electrical connector 4, the upper pressure plate 6 is placed below the vertical screw 7. Rotating the vertical screw 7 allows it to move up and down vertically, thus applying pressure to the upper pressure plate 6 and clamping the coil strands 15. Furthermore, a first rotating handle 8 is located at the upper end of the vertical screw 7, making it more convenient and effortless for the operator to rotate it.

[0028] In some embodiments, refer to Figure 1The first clamping mechanism includes two vertical rods 2, which are respectively connected to the two ends of a horizontal rod 3. A transverse screw 11 is threaded through the vertical rod 2, and a side pressure plate 10 is provided at the end of the transverse screw 11 closest to the induction heating device 9. When the induction heating device 9 is clamped to the outside of the electrical connector 4, rotating the transverse screws 11 on both sides causes the two side pressure plates 10 to press tightly from both sides, making the induction heating device 9 fit tightly against the electrical connector 4, improving heat transfer efficiency, and simultaneously allowing the opening of the expanded wire connection portion of the electrical connector 4 to shrink and return to its original state. Furthermore, a second rotating handle 12 is provided at the end of the transverse screw 11 furthest from the induction heating device 9, making it more convenient and effortless for the operator to rotate. Preferably, a guide rod 13 freely passing through the vertical rod 2 is connected to the side pressure plate 10. This design ensures that the side pressure plate 10 presses along a straight line, avoiding deviation and improving brazing quality.

[0029] In some embodiments, refer to Figure 1 The lower end of the vertical rod 2 is connected to a support plate 1 for supporting the electrical connector mounting plate 5. This design allows the support plate 1, in conjunction with the upper pressure plate 6, to be more easily clamped without the need for additional support. It is worth noting that the support plate 1 can be a single plate with a stepped structure, longer at the bottom and shorter at the top. In use, the electrical connector mounting plate 5 can be placed on the lower step. Alternatively, the support plate 1 can be made by overlapping and welding two metal plates, with the lower plate longer than the upper plate, and the electrical connector mounting plate 5 resting on the lower plate. Furthermore, the vertical rod 2 is hinged to the horizontal rod 3. This design allows the vertical rod 2 to be rotated open before the first and second clamping mechanisms clamp, facilitating assembly and making the entire brazing fixture more flexible and easier to operate. After the electrical connector 4, coil strands 15, and brazing filler metal are assembled, the vertical rod 2 can be fixed. The fixing method involves using bolts or similar structures to fix it to the workbench or other locations through the pre-drilled mounting holes on the support plate 1. This is a common fixing method in existing technology and will not be elaborated further.

[0030] According to the second aspect of this application, such as Figures 1 to 5 As shown, a brazing method is provided, using the aforementioned brazing fixture, including: assembling the brazing fixture into place; installing and fixing the electrical connector 4; assembling the coil strands 15 and the brazing filler metal; arranging the coil strands 15 and the brazing filler metal; activating the induction heating device 9; and adjusting the first clamping mechanism and the second clamping mechanism in a timely manner according to the melting state of the brazing filler metal to obtain a brazed finished product. The coil strands 15 and the brazing filler metal are assembled onto the electrical connector 4, and the electrical connector 4 is assembled onto the electrical connector mounting plate 5. The conductor portion passes through the through hole, the strand connection portion is placed on the electrical connector mounting plate 5, the induction heating device 9 is positioned tightly against the electrical connector 4, the first clamping mechanism clamps the coil strands 15, and the second clamping mechanism clamps the induction heating device 9.

[0031] In specific operation, the induction heating device 9 is activated, and the temperature rise of the electrical connector 4 and its coil strands 15 is observed. When the entire sealing section 20 turns orange-red and the pre-placed sheet-like brazing filler metal melts and begins to flow, the second clamping mechanism is tightened first to achieve a tight fit of the expanded electrical connector 4. The second clamping mechanism is then loosened, and the first clamping mechanism is tightened to form a regular square shape within the cavity of the electrical connector 4. Then, the first clamping mechanism is loosened again, and the second clamping mechanism is tightened again to release air. After venting, the first clamping mechanism is tightened again to flatten the coil strands 15 using the upper surface of the electrical connector 4 as a reference. Throughout the extrusion process, the induction heating device 9 is energized intermittently to keep the brazing filler metal in a molten state.

[0032] Continue pressing the power button on the induction heating device 9 to continuously increase the temperature. The molten brazing material overflows evenly along the end face of the electrical connector 4. Stop heating when the brazing corners around the electrical connector 4 are rounded and full. Only when the color of the sealing section 20 turns completely black can the second clamping mechanism be released and the induction heating device 9 be removed. At this time, keep the clamping state of the first clamping mechanism until the coil strands 15 and the electrical connector 4 brazed to them cool down and are demolded, thus completing the brazing.

[0033] In one embodiment, assembling the coil strands 15 and the solder includes: using a forming block to bulge the cavity of the electrical connector 4 from the opening end of the strand mounting slot; inserting the coil strands into the bulged cavity; and inserting solder between the coil strands and the cavity wall. To facilitate the assembly of the electrical connector 4 and the coil strands 15, a forming block can be used to bulge the cavity of the electrical connector 4 from the opening end. After bulging, the width of the opening of the electrical connector 4 allows for easy assembly of the coil strands 15 and the solder.

[0034] In one embodiment, the preparation of the coil strands 15 and the brazing filler metal includes: clamping and fixing the coil strands 15 in the strand mounting groove, the coil strands 15 including the section to be cut extending out of the strand mounting groove; after clamping the section to be cut, cutting the section to be cut close to the electrical connector 4 to make its cross-section flat; wherein, each coil strand 15 is free from collapse, curling, crossing, and misalignment. To further improve the brazing quality, burrs and flanging can be removed from the cross-section. It should be noted that the brazing filler metal can be pre-inserted and prepared together when the section to be cut is cut. Alternatively, it can be inserted after the section to be cut is cut from the coil strands 15, with 0.4mm sheet-shaped intermediate brazing filler metal 16 pre-inserted between the two rows of coil strands 15, and two 0.2mm sheet-shaped side brazing filler metal 14 pre-inserted into the cavity of the electrical connector 4, one piece on each side wall, and flush with the end face of the cavity. The sealing section 20 behind the electrical connector 4 only requires a 0.4mm sheet of intermediate brazing filler metal 16 pre-placed between the two rows of coil strands 15. Loosening the first and second clamping mechanisms and installing the electrical connector 4 with the pre-placed sheet of brazing filler metal onto the electrical connector mounting plate 5 ensures that the electrical connector 4 is perpendicular to the coil strands 15 after sealing, guaranteeing brazing quality.

[0035] According to the third aspect of this application, such as Figures 1 to 5 As shown, a brazing quality inspection method is provided, which inspects the brazed products obtained by the above-described brazing method, including: Determine the baseline for the flaw detection sensitivity of the UT flaw detector; The brazed joint area was inspected using a UT flaw detector to obtain the flaw detection reflection signal; The flaw detection reflection signal is compared with the flaw detection sensitivity benchmark to obtain the flaw detection result.

[0036] Optionally, determining the flaw detection sensitivity benchmark for the UT flaw detector includes scanning the unbrazed electrical connector 4 with a single-crystal straight probe to find the bottom reflection echo, adjusting the first bottom reflection echo to 80% of the height of the UT flaw detector screen; simultaneously adjusting the scanning range and continuing to repeat the steps of finding the bottom reflection echo, adjusting the fifth bottom reflection echo to be displayed on the UT flaw detector screen so that the first to fifth bottom reflection echoes can be displayed on the UT flaw detector screen; increasing the gain by 12dB as the flaw detection sensitivity benchmark.

[0037] The process involves using a UT flaw detector to inspect the brazed joint area and obtain flaw detection reflection signals. This includes uniformly applying coupling agent to the flaw detection surface of the electrical connector 4, and moving the probe of the UT flaw detector over the brazed joint area of ​​the electrical connector 4 with the adjusted flaw detection sensitivity reference to detect any suspicious reflection signals. The overlap width of the UT flaw detector probe during inspection is not less than 15% of the probe chip size. like Figure 6 As shown, the flaw detection reflection signal is compared with the flaw detection sensitivity benchmark to obtain the flaw detection result, including: when the reflected echo generated by the brazed joint area reaches or exceeds the amplitude height of the flaw detection sensitivity benchmark, it is considered to be a brazed defect area; where a brazed defect area with a sensitivity greater than the benchmark is detected in the brazed joint area, the reflected echo of the brazed defect area is reduced to 40% of the screen height as the defect boundary point of the defect area, and the area enclosed by all boundary points is the brazed defect area.

[0038] In the description of this application, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more features. In the description of this application, "multiple" means two or more, unless otherwise explicitly specified.

[0039] In the above embodiments, the descriptions of each embodiment have different focuses. For parts not described in detail in a certain embodiment, please refer to the relevant descriptions in other embodiments.

[0040] The embodiments, implementation methods, and related technical features of this application can be combined and substituted for each other without conflict.

[0041] The above are merely preferred embodiments of this application and are not intended to limit this application in any way. Any simple modifications, equivalent changes, and alterations made to the above embodiments based on the technical essence of this application without departing from the scope of the technical solution of this application shall still fall within the scope of the technical solution of this application.

Claims

1. A brazing fixture, characterized in that, include: The electrical connector mounting plate (5) is configured to install and place the electrical connector (4). An induction heating device (9) is configured to heat the electrical connector (4) and the coil strands (15) and brazing filler metal assembled to the electrical connector (4); A first clamping mechanism is configured to clamp the coil strands (15); the first clamping mechanism includes a crossbar (3), on which a vertical screw (7) is threaded through, and an upper pressure plate (6) for pressing the coil strands (15) is provided at the lower end of the vertical screw (7); wherein, a first rotating handle (8) is provided at the upper end of the vertical screw (7); The second clamping mechanism is configured to cause the induction heating device to make close contact with the electrical connector (4). The second clamping mechanism includes two vertical rods (2), which are respectively connected to the two ends of the horizontal rod (3). A transverse screw (11) is threaded through the vertical rod (2). A side pressure plate (10) is provided at the end of the transverse screw (11) near the induction heating device (9). A second rotating handle (12) is provided at the end of the transverse screw (11) away from the induction heating device (9). A guide light rod (13) that freely passes through the vertical rod (2) is connected to the side pressure plate (10). The electrical connector (4) includes an integrally formed strand connection part and a conductor part. The outer circumferential dimension of the strand connection part is larger than the outer circumferential dimension of the conductor part. The electrical connector mounting plate (5) has a through hole for the conductor part to pass through. The electrical connector mounting plate (5) is used to support the strand connection part. The induction heating device (9) includes an induction coil frame (17), on which a heating induction coil is disposed; The heating induction coil includes: The front coil (18) is used to heat the sealing section (20) of the coil strands (15) located outside the electrical connector (4). The rear coil (19) is used to heat the connecting section of the coil strands (15) that extend into the electrical connector (4); Both the front-end coil (18) and the rear-end coil (19) are made of magnetic materials.

2. The brazing fixture according to claim 1, characterized in that, The lower end of the vertical rod (2) is connected to a support plate (1) for supporting the electrical connector mounting plate (5), and the vertical rod (2) is hinged to the horizontal rod (3).

3. A brazing method, characterized in that, The brazing fixture described in any one of claims 1-2 is used, and the brazing method includes: Assemble the brazing fixture into place, install and fix the electrical connector (4), assemble the coil strands (15) and the brazing filler metal; Organize the coil strands (15) and the brazing filler metal; Start the induction heating device (9), and adjust the first clamping mechanism and the second clamping mechanism in a timely manner according to the melting state of the brazing filler metal to obtain the brazed finished product.

4. The brazing method according to claim 3, characterized in that, The assembly of the coil strands (15) and the brazing filler metal includes: The cavity of the electrical connector (4) is bulged from the opening end of the strand mounting groove of the electrical connector (4) using an bulging block; The coil strands are inserted into the bulging cavity; The brazing filler metal is inserted between the coil strands and the cavity wall. The preparation of the coil strands (15) and the brazing filler metal includes: The coil strands (15) are clamped and fixed in the strand mounting groove, and the coil strands (15) include a section to be cut out that extends out of the strand mounting groove; Clamp the section to be cut, press it against the electrical connector (4) to cut the section to be cut, and make its cross-section flat; wherein each coil strand (15) has no collapsed edge, no curling, no crossing, and no misalignment.

5. A method for inspecting brazing quality, characterized in that, For testing the brazed product obtained by the brazing method according to claim 3 or 4, including: Determine the baseline sensitivity of the UT flaw detector; The UT flaw detector is used to examine the brazed joint area and obtain the flaw detection reflection signal; The flaw detection reflection signal is compared with the flaw detection reference sensitivity to obtain the flaw detection result.

6. The brazing quality inspection method according to claim 5, characterized in that, Determining the flaw detection reference sensitivity of the UT flaw detector includes: Using a single crystal straight probe, scan the unbrazed electrical connector (4) to find the bottom reflection echo. Adjust the first bottom reflection echo to 80% of the height of the UT flaw detector screen. Adjust the scanning range and continue to repeat the steps of finding the bottom reflection echo. Adjust the fifth bottom reflection echo to the UT flaw detector screen so that the first to fifth bottom reflection echoes can be displayed on the UT flaw detector screen. Increase the gain by 12dB as the flaw detection reference sensitivity. The step of using the UT flaw detector to inspect the brazed joint area and obtain the flaw detection reflection signal includes: uniformly brushing a coupling agent onto the flaw detection surface of the electrical connector (4); using the probe of the UT flaw detector at the adjusted flaw detection reference sensitivity to move in the brazed joint area of ​​the electrical connector (4) to detect suspicious reflection signals; wherein, when the probe of the UT flaw detector moves to detect, the overlap width is not less than 15% of the probe chip size; The step of comparing the flaw detection reflection signal with the flaw detection reference sensitivity to obtain the flaw detection result includes: when the reflected echo generated by the brazed joint area reaches or exceeds the amplitude height of the flaw detection reference sensitivity, it is considered to be a brazed defect area; wherein, if a brazed defect area with a value greater than the reference sensitivity is detected in the brazed joint area, the reflected echo of the brazed defect area is reduced to 40% of the screen height as the defect boundary point of the defect area, and the area enclosed by all boundary points is the brazed defect area.

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