Power module welding tool jig

Abstract

The power module welding tool jig comprises a base, a copper bottom plate, a lining plate frame and two pressing blocks, the lining plate frame, the copper bottom plate and the base are sequentially stacked from top to bottom, a hollowed-out containing opening is formed in the lining plate frame, and the two pressing blocks are arranged in the containing opening. A containing opening is formed in the top of the copper bottom plate, two insulating lining plates stacked on the top of the copper bottom plate are placed in the containing opening, two pressing blocks are arranged in the containing opening side by side, the two pressing blocks are stacked on the tops of the two insulating lining plates respectively, and a tin material is placed between the insulating lining plates and the copper bottom plate. A barrier strip capable of moving up and down is arranged between the edges of the two sides of the containing opening, and the two insulating lining plates and the two pressing blocks are separated through the barrier strip. According to the utility model, the insulation lining plate can be prevented from deviating, and soldering tin can be prevented from overflowing.

Description

Technical Field

[0001] The utility model relates to a power module welding device, in particular to a power module welding tooling fixture. Background Art

[0002] When the existing technology is used for power module welding and processing, due to the sharp temperature fluctuation in the welding furnace, sometimes the temperature difference can reach more than 200 degrees Celsius. Coupled with the inherent physical properties of the fixture material itself, the copper bottom plate will undergo thermal deformation. In order to reduce the gap caused by thermal deformation, when processing the copper bottom plate, it is necessary to pre-design a certain arc to meet the process requirements. However, this arc will also continuously undergo micro-deformation adjustment with the dynamic change of temperature during the welding process. At this time, problems such as increased gap opening and insufficient welding accuracy of the originally precisely docked welding tooling fixture will occur, such as abnormal overflow of solder, position offset of the insulating lining plate, etc., reducing the welding quality of the power module. Summary of the Utility Model

[0003] The technical problem to be solved by the utility model is to provide a power module welding tooling fixture that can avoid the offset of the insulating lining plate and prevent the overflow of solder, aiming at the deficiencies of the existing technology.

[0004] To solve the above technical problem, the utility model adopts the following technical solutions.

[0005] A power module welding tooling fixture includes a base, a copper bottom plate, a lining plate frame, and two pressing blocks. The lining plate frame, the copper bottom plate, and the base are stacked in sequence from top to bottom. The lining plate frame is provided with a hollow accommodation opening. Two insulating lining plates stacked on the top of the copper bottom plate are placed in the accommodation opening. The two pressing blocks are arranged side by side in the accommodation opening, and the two pressing blocks are respectively stacked on the tops of the two insulating lining plates. A tin material is placed between the insulating lining plate and the copper bottom plate. A vertically movable stop bar is provided between the two side edges of the accommodation opening, and the two insulating lining plates are separated and the two pressing blocks are separated by the stop bar.

[0006] Preferably, limiting step blocks are respectively provided at the four corners of the base, and the copper bottom plate is arranged between the four limiting step blocks.

[0007] Preferably, anti-fooling copper columns are respectively provided at positions close to both sides of the lining plate frame, and the anti-fooling copper columns can sequentially penetrate through the anti-fooling holes on the copper bottom plate and the base.

[0008] Preferably, a plurality of protruding abutting blocks are evenly distributed on the inner side wall of the accommodation opening, and the protruding abutting blocks are in abutting cooperation with the edges of the pressing blocks.

[0009] Preferably, the tin material placed under the insulating lining plate is solder paste or solder sheet.

[0010] Preferably, a plurality of component through-holes for placing components are formed in the pressing block.

[0011] Preferably, two upwardly protruding lugs are provided on the top of the pressing block.

[0012] Preferably, two symmetrically arranged vertical sliding grooves are formed in the inner side wall of the lining plate frame, and both ends of the retaining strip are respectively arranged in the two vertical sliding grooves, and both ends of the retaining strip are respectively in sliding fit with the two vertical sliding grooves.

[0013] Preferably, two sealing strips are detachably fixed on the top of the lining plate frame, and the two sealing strips respectively cover the two vertical sliding grooves.

[0014] Preferably, two downwardly protruding abutting feet are formed at the lower end of the retaining strip, and both abutting feet abut against the copper bottom plate.

[0015] In the power module welding tooling fixture disclosed by the present utility model, first stack the copper bottom plate on the base, then stack the lining plate frame on the copper bottom plate, and then insert the retaining strip between the two side edges of the receiving opening, and ensure that the retaining strip can move up and down. Then place the tin material on the top of the copper bottom plate, place the two insulating lining plates side by side in the receiving opening, separate the two insulating lining plates by using the retaining strip, and then arrange the two pressing blocks side by side in the receiving opening, separate the two pressing blocks by using the retaining strip. Place the tooling assembled by the above steps in a welding furnace. During the welding process, the tin material under the insulating lining plate melts and flows along the preset grooves on the insulating lining plate. Then take the tooling out of the welding furnace, cool it, and detect the welding quality. After checking and confirming, disassemble the fixture, take out the welded device, and clean the fixture. In the above structure, because there is a retaining strip that can move up and down between the two side edges of the receiving opening, and the two insulating lining plates are separated and the two pressing blocks are separated by using the retaining strip, it can avoid the two insulating lining plates from contacting each other and prevent the insulating lining plates from shifting, so that a certain distance is maintained between the two insulating lining plates. When the tin material melts, it can avoid the situation of solder adhesion caused by the direct contact of the two insulating lining plates. At the same time, the retaining strip separates the two pressing blocks, which can reliably position the two pressing blocks. Even when the copper bottom plate undergoes thermal deformation, the up and down position of the retaining strip can be finely adjusted, and during this process, the separation and positioning effects on the two pressing blocks can be maintained, thereby ensuring the alignment of the positions between the pressing block and the insulating lining plate. During the melting and flowing process of the tin material, it can prevent the solder from overflowing, and then accurately weld with the components positioned on the pressing block. Description of the Drawings

[0016] Figure 1 is a perspective view of the welding tooling fixture of the present utility model;

[0017] Figure 2 This is a sectional perspective view of the welding tooling fixture of the present utility model;

[0018] Figure 3 This is an exploded view of the welding tooling fixture of the present utility model;

[0019] Figure 4 This is a partial sectional view of the welding tooling fixture of the present utility model;

[0020] Figure 5 This is a schematic diagram of the thermal deformation of the copper base plate during the welding process. Specific embodiments

[0021] The present utility model will be described in more detail below with reference to the accompanying drawings and embodiments.

[0022] The present utility model discloses a welding tooling fixture for a power module. As shown in combination Figures 1 to 5 , it includes a base 1, a copper base plate 2, a lining plate frame 3, and two pressing blocks 4 for positioning components. The lining plate frame 3, the copper base plate 2, and the base 1 are stacked in sequence from top to bottom. The lining plate frame 3 is provided with a hollow accommodation opening 30. Two insulating lining plates 5 stacked on the top of the copper base plate 2 are placed in the accommodation opening 30. The two pressing blocks 4 are arranged side by side in the accommodation opening 30, and the two pressing blocks 4 are respectively stacked on the tops of the two insulating lining plates 5. A tin material is placed between the insulating lining plate 5 and the copper base plate 2. A movable stop bar 6 is provided between the two side edges of the accommodation opening 30 to separate the two insulating lining plates 5 and the two pressing blocks 4.

[0023] During the process of welding the power module using the welding tooling fixture of the present utility model, first stack the copper base plate 2 on the base 1, then stack the liner frame 3 on the copper base plate 2. After that, insert the retaining bar 6 between the two side edges of the receiving opening 30 and ensure that the retaining bar 6 can move up and down. Then place the tin material on the top of the copper base plate 2, place the two insulating liners 5 side by side in the receiving opening 30, and separate the two insulating liners 5 by using the retaining bar 6. Then arrange the two pressing blocks 4 side by side in the receiving opening 30 and separate the two pressing blocks 4 by using the retaining bar 6. Place the tooling assembled by the above steps in the welding furnace. During the welding process, the tin material under the insulating liner 5 melts and flows along the preset grooves on the insulating liner 5. After that, take the tooling out of the welding furnace, cool it, and detect the welding quality. After checking and finding no errors, disassemble the fixture, take out the welded device, and clean the fixture. In the above structure, since there is a retaining bar 6 that can move up and down between the two side edges of the receiving opening 30, and the two insulating liners 5 and the two pressing blocks 4 are separated by using the retaining bar 6, it can avoid the two insulating liners 5 from contacting each other and prevent the insulating liners from shifting, so that a certain distance is maintained between the two insulating liners 5. When the tin material melts, it can avoid situations such as solder adhesion due to the direct contact of the two insulating liners 5. At the same time, the retaining bar 6 separates the two pressing blocks 4 and can reliably position the two pressing blocks 4. Even when the copper base plate 2 undergoes thermal deformation, the up and down position of the retaining bar 6 can be finely adjusted. During this process, the separation and positioning effects on the two pressing blocks 4 can be maintained, thereby ensuring the alignment of the positions between the pressing block 4 and the insulating liner 5. During the melting and flowing process of the tin material, it can prevent the solder from overflowing, and then accurately weld with the components positioned on the pressing block 4.

[0024] In order to reliably position the copper base plate 2, in this embodiment, limit step blocks 10 are respectively provided at the four corners of the base 1, and the copper base plate 2 is arranged between the four limit step blocks 10. In practical applications, the limit step block 10 can be an L-shaped step block.

[0025] As a preferred method, anti-fooling copper posts 31 are respectively provided at positions near the two sides of the liner frame 3. The anti-fooling copper posts 31 can sequentially penetrate the anti-fooling holes on the copper base plate 2 and the base 1. The anti-fooling copper posts 31 can play a role in overall positioning of the liner frame 3, the copper base plate 2, and the base 1.

[0026] Please refer to Figure 3, in this embodiment, a plurality of protruding abutting blocks 32 are evenly distributed on the inner side wall of the accommodating opening 30, and the protruding abutting blocks 32 are in abutting cooperation with the edge of the pressing block 4. Among them, in this embodiment, it is preferably to arrange a plurality of protruding abutting blocks 32 on the inner side wall of the accommodating opening 30, and use the plurality of protruding abutting blocks 32 to limit the position of the pressing block 4. Compared with the assembly method in which the shape of the accommodating opening 30 is the same as that of the pressing block 4, this embodiment can significantly reduce the friction between the pressing block 4 and the inner side wall of the accommodating opening 30, facilitating the loading and unloading of the pressing block 4.

[0027] As a preferred material, in this embodiment, the tin material placed under the insulating lining plate 5 is solder paste or solder sheet.

[0028] Combined Figures 1 to 3 As shown, in this embodiment, a plurality of component through holes 40 for placing components are formed in the pressing block 4. In actual application, after two pressing blocks 4 are arranged side by side in the accommodating opening 30, tin material is placed in the component through holes 40, and components such as chips and resistors are correspondingly loaded into each component through hole 40 so that the pins of components such as chips and resistors are aligned with the welding positions on the insulating lining plate 5. During the welding process, the solder paste or solder sheet can be accurately connected to the component pins after melting. In this embodiment, by arranging the retaining strip 6, the two pressing blocks 4 can be reliably positioned, thereby ensuring the alignment of the position between the pressing block 4 and the insulating lining plate 5. During the melting and flowing process of the tin material, precise welding can be performed with the pins of the components.

[0029] As a preferred method, two upwardly protruding lugs 41 are provided on the top of the pressing block 4. Among them, the upwardly protruding lugs 41 can facilitate the user to lift the pressing block 4.

[0030] To enable the retaining strip 6 to slide up and down relative to the lining frame 3, in this embodiment, two symmetrically arranged vertical sliding grooves 33 are formed in the inner side wall of the lining frame 3, and both ends of the retaining strip 6 are respectively arranged in the two vertical sliding grooves 33, and both ends of the retaining strip 6 are respectively in sliding cooperation with the two vertical sliding grooves 33. By arranging the vertical sliding grooves 33 in this embodiment, it is convenient to insert the retaining strip 6 and provides a space for the retaining strip 6 to move up and down.

[0031] On this basis, two sealing strips 7 are detachably fixed to the top of the lining frame 3, and the two sealing strips 7 respectively cover the two vertical sliding grooves 33. Among them, the sealing strips 7 are preferably detachably fixed by screws. Since the two sealing strips 7 are fixed to the top of the lining frame 3, they can not only limit the up and down movement amount of the retaining strip 6, but also do not affect the loading and unloading of the pressing block 4.

[0032] As a preferred embodiment, two downwardly protruding abutting feet 60 are formed at the lower end of the retaining bar 6, and both of the two abutting feet 60 are abutted against the copper base plate 2. Among them, when the copper base plate 2 undergoes thermal deformation, if the retaining bar 6 in this embodiment is not provided, the two pressing blocks 4 and the two insulating liners 5 will shift along with the deformation of the copper base plate 2. However, in this embodiment, as Figure 5 shown, the abutting feet 60 are used to abut against the copper base plate 2, and the retaining bar 6 will undergo fine adjustment of its vertical position along with the deformation of the copper base plate 2, so that the retaining bar 6 remains in a state of separating the two pressing blocks 4 and separating the two insulating liners 5, thereby aligning the positions between the pressing block 4 and the insulating liner 5, and significantly improving the welding accuracy.

[0033] Furthermore, the advantage of setting two abutting feet 60 in this embodiment is that the two abutting feet 60 can undergo fine adjustment of their vertical positions along with the copper base plate 2 when the copper base plate 2 undergoes thermal deformation. Compared with a straight retaining bar, the two abutting feet 60 in this embodiment can increase the vertical movement amount of the retaining bar 6, so as to better fit with the copper base plate 2.

[0034] On this basis, this embodiment also proposes a power module welding method. As shown in Figures 1 to 5 shown, this welding method is realized based on the above-mentioned welding tooling fixture, and the welding method includes the following steps:

[0035] Step S1, stacking the copper base plate 2 on the base 1;

[0036] Step S2, stacking the liner frame 3 on the copper base plate 2;

[0037] Step S3, inserting the retaining bar 6 between the two side edges of the receiving opening 30 and ensuring that the retaining bar 6 can move up and down;

[0038] Step S4, placing tin material on the top of the copper base plate 2;

[0039] Step S5, placing the two insulating liners 5 side by side in the receiving opening 30 and separating the two insulating liners 5 by using the retaining bar 6;

[0040] Step S6, arranging the two pressing blocks 4 side by side in the receiving opening 30 and separating the two pressing blocks 4 by using the retaining bar 6;

[0041] Step S7, placing the tooling assembled from Step S1 to Step S6 in a welding furnace. During the welding process, the tin material under the insulating liner 5 melts and flows along the preset grooves on the insulating liner 5, and the melted tin material is also connected to the components positioned by the pressing blocks 4;

[0042] Step S8, take out the tooling from the soldering furnace and cool it, and then detect the soldering quality;

[0043] Step S9, after checking and confirming, disassemble the jig, take out the soldered device, and clean the jig.

[0044] Furthermore, the tin material placed in step S4 is solder paste or solder sheet. In step S8, an X-ray device is used to detect the soldering quality inside the tooling. Of course, manual inspection or cooperation with other devices can also be used for inspection.

[0045] In the preferred embodiment of the present utility model, soldering can be achieved by referring to the following steps:

[0046] Step 1, base preparation: Place the copper base plate in the base. The function of the base is to support the entire structure and provide a stable working platform;

[0047] Step 2, insulating liner frame positioning: Place the insulating liner frame on the copper base plate. Use anti-fooling copper posts to position the insulating liner frame to ensure the accurate and stable position of the frame;

[0048] Step 3, insulating liner isolation: Use a bar to separate the insulating liners to prevent the two DBCs from coming into contact during soldering. Use a sealing strip and lock it with screws to ensure that the bar will not come out during soldering;

[0049] Step 4, place DBC: Add solder paste or solder sheet on the copper base plate. The function of the solder is to melt and fill the gap between the insulating liner and the copper base plate during soldering to achieve electrical connection between the two. According to the shape and size of the DBC frame, place the insulating liner on the copper base plate and ensure its alignment with the frame;

[0050] Step 5, place the pressure block: According to the markings on the insulating liner frame, place the pressure block on the insulating liner. The function of the pressure block is to ensure that components such as chips and resistors on the insulating liner maintain the correct position during soldering;

[0051] Step 6, chip and resistor placement: Add an appropriate amount of solder paste or solder sheet between the pressure blocks and at the specified positions, and place components such as chips, surface mount resistors, and thermistors;

[0052] Step 7, soldering: Place the entire jig into the soldering furnace for soldering operations. During soldering, the solder will melt and flow to achieve electrical connection with the pins of components such as the insulating liner, chips, and resistors;

[0053] Step 8, cooling and detection: After soldering, let the jig cool naturally or use air cooling to accelerate cooling. After cooling, conduct soldering quality inspection, such as using X-ray to detect the internal connection situation, etc.;

[0054] Step 9, Disassembly and Cleaning: After inspection, disassemble the fixture, take out the power module that has been welded, clean the fixture, and prepare for the next use.

[0055] By using the above fixture, the welding accuracy and efficiency can be greatly improved, ensuring the quality and reliability of the power module.

[0056] In the specific process flow of the welding operation, this fixture is also designed with an automatic calibration positioning design. The middle bar of the fixture is placed in the wire groove of the insulating lining plate frame. There is space above and below the wire groove, and the bar can move up and down. At the beginning of welding, the bar sinks and contacts the copper bottom plate, while separating the insulating lining plates on both sides. During the welding process, the curvature of the copper bottom plate will change, and the bar will move up and down with the change of the curvature of the copper bottom plate, keeping close contact with the copper bottom plate, playing the role of isolating the insulating lining plates, and having technical effects such as preventing solder overflow and preventing the insulating lining plates from shifting.

[0057] The above are only the preferred embodiments of the present invention and are not used to limit the present invention. Any modifications, equivalent replacements, or improvements made within the technical scope of the present invention shall be included within the scope protected by the present invention.

Claims

1. A power module welding fixture, characterized in that: The invention comprises a base (1), a copper bottom plate (2), a lining frame (3) and two pressing blocks (4) for positioning components. The lining frame (3), the copper bottom plate (2) and the base (1) are stacked in sequence from top to bottom. The lining frame (3) is provided with a hollow receiving opening (30). Two insulating linings (5) stacked on top of the copper bottom plate (2) are placed in the receiving opening (30). Two pressing blocks (4) are arranged side by side in the receiving opening (30), and the two pressing blocks (4) are respectively stacked on top of the two insulating linings (5). Tin material is placed between the insulating linings (5) and the copper bottom plate (2). A baffle (6) that can move up and down is provided between the two side edges of the receiving opening (30), and the two insulating linings (5) and the two pressing blocks (4) are separated by the baffle (6).

2. The power module welding fixture as claimed in claim 1, characterized in that: Position limiting step blocks (10) are respectively arranged at the four corners of the base (1), and the copper bottom plate (2) is arranged between the four position limiting step blocks (10).

3. The power module welding fixture as claimed in claim 1, characterized in that: The lining frame (3) is provided with fool-proof copper columns (31) near the two sides, respectively. The fool-proof copper columns (31) can be inserted into the fool-proof holes on the copper bottom plate (2) and the base (1) in sequence.

4. The power module welding fixture as claimed in claim 1, characterized in that: The inner side wall of the accommodating opening (30) is evenly distributed with a plurality of protruding abutting blocks (32), and the protruding abutting blocks (32) abut against the edge of the pressing block (4).

5. The power module welding fixture as claimed in claim 1, characterized in that: The tin material placed on the lower side of the insulating lining (5) is solder paste or solder sheet.

6. The power module welding fixture as claimed in claim 1, characterized in that: The pressing block (4) is provided with a plurality of component through holes (40) for placing components.

7. The power module welding fixture as claimed in claim 1, characterized in that: The top of the pressing block (4) is provided with two upwardly protruding ears (41).

8. The power module welding fixture as claimed in claim 1, characterized in that: The inner side wall of the lining frame (3) is provided with two symmetrically arranged vertical slide grooves (33), the two ends of the blocking bar (6) are respectively arranged in the two vertical slide grooves (33), and the two ends of the blocking bar (6) are respectively slidably matched with the two vertical slide grooves (33).

9. The power module welding tool as claimed in claim 8, characterized in that: Two seals (7) are detachably fixed on the top of the lining frame (3), and the two seals (7) respectively cover the two vertical slide grooves (33).

10. The power module welding tool as claimed in claim 1, characterized in that: Two downwardly protruding abutting feet (60) are formed at the lower end of the blocking bar (6), and the two abutting feet (60) are both in abutment with the copper bottom plate (2).

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