Welding positioning mechanism for power module
By designing a positioning frame and pulling mechanism for the power module, the problems of uneven thickness and difficult disassembly caused by the deformation of the encapsulation during the welding process were solved, achieving uniformity of the welded layer and convenient disassembly, thereby improving product reliability and production efficiency.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-04-02
- Publication Date
- 2026-04-14
AI Technical Summary
In the prior art, the power module is deformed during the welding process due to the large linear thermal expansion coefficient of the plastic package. It is easily stuck or suspended by the positioning block, resulting in uneven weld layer thickness and voids. Furthermore, it is difficult to disassemble, which affects the reliability and lifespan of the product.
Design a welding positioning mechanism that includes a positioning frame and a pulling mechanism. Through the cooperation of sliders and pull blocks, and by utilizing the inclined or curved surface structure and the elastic force of springs, the stable positioning and disassembly of the encapsulated body can be achieved, ensuring the uniformity of the weld layer thickness and the ease of disassembly.
This solution addresses the issues of uneven thickness and disassembly difficulties caused by deformation of the encapsulated body during welding, thereby improving the welding quality and production efficiency of power modules and extending product lifespan.
Smart Images
Figure CN224115489U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of power module manufacturing technology, specifically a welding positioning mechanism for power modules. Background Technology
[0002] In existing technologies, the soldering of power modules involves self-overlapping the heat sink substrate, solder, and molding compound. During the cooling process of reflow soldering, the high linear thermal expansion coefficient of the molding compound makes the product prone to deformation. This can cause the molding compound to be stuck or suspended by the positioning blocks, resulting in uneven solder layer thickness—a thicker layer at the suspended end and a thinner layer at the other. This leads to uneven heat conduction during product dissipation, reducing reliability. In more severe cases, both ends may be suspended, resulting in voids. Furthermore, after soldering, the significant deformation of the molding compound makes it extremely tight against the conventional positioning blocks, making disassembly difficult. Forcible disassembly can easily render the product unusable. Summary of the Invention
[0003] Purpose of the utility model: To solve the problems existing in the prior art, this utility model provides a welding positioning mechanism for power modules.
[0004] Technical Solution: This utility model discloses a welding positioning mechanism for a power module, comprising a positioning frame, on which a positioning mechanism is mounted, and the positioning mechanism is connected to a pulling mechanism. The positioning mechanism includes multiple pairs of sliders, each slider having a positioning claw at one end and the other end located within a hole in the positioning frame, where a first spring is disposed. The pulling mechanism includes multiple pull blocks, each pull block positioned between the pairs of sliders. The pull blocks are used to drive the pairs of sliders to separate from each other.
[0005] Furthermore, the surface in contact between the pull block and the slider is an inclined surface or a curved surface.
[0006] Furthermore, the pulling mechanism includes a movable plate, and the pulling block is connected to the movable plate; the movable plate is movably connected to the positioning frame.
[0007] Furthermore, the two ends of the movable plate are connected to the positioning frame by equal-height screws, and a second spring is provided on the screw of the equal-height screw, the second spring being located between the movable plate and the head of the equal-height screw.
[0008] Furthermore, pins are provided on the movable plate.
[0009] Furthermore, screws are provided on the movable plate.
[0010] Furthermore, the positioning frame is provided with positioning pins.
[0011] Furthermore, a cover plate is provided on the positioning frame, and the slider is covered by the cover plate.
[0012] Beneficial effects: Compared with the prior art, this utility model has the following beneficial effects:
[0013] 1. This utility model solves the problem of difficult disassembly caused by product deformation after welding by setting a pulling mechanism to force the paired sliders to move to both sides;
[0014] 2. It solves the problem of voids caused by deformation during the welding process, resulting in a uniform weld layer thickness in the power module and thus improving the lifespan of the power module. Attached Figure Description
[0015] Figure 1 This is a schematic diagram of the structure of this utility model;
[0016] Figure 2 This is a top view of the structure of this utility model, with the cover plate omitted.
[0017] Figure 3 for Figure 2 A partial structural diagram at point A, currently in a positioning state;
[0018] Figure 4 for Figure 2 A partial structural diagram at point A, showing the area in a loosened state.
[0019] In the diagram: 1-positioning frame; 2-pull mechanism; 3-slider; 4-cover plate; 5-molded body; 6-heat dissipation base plate; 11-body; 12-positioning pin; 13-spring; 20-moving plate; 21-pull block; 22-pin; 31-spring; 32-positioning claw; 101-hole; 14-equal height screw. Detailed Implementation
[0020] The technical solution of this utility model will be further described below with reference to the accompanying drawings.
[0021] like Figure 1-4 As shown, this utility model discloses a welding positioning mechanism for a power module, comprising a positioning frame 1, the positioning frame 1 including a body 11; a positioning mechanism is provided on the positioning frame 1, the positioning mechanism being connected to a pulling mechanism 2; specifically, the positioning mechanism and the pulling mechanism 2 are provided on the body 11. The positioning mechanism includes multiple pairs of sliders 3, such as... Figure 1 and Figure 2 As shown, in this embodiment, six pairs of sliders 3 are arranged, which can simultaneously position three encapsulated bodies 5 in the X direction. However, this utility model does not limit the specific number of sliders 3.
[0022] like Figure 2-4As shown, each slider 3 can be L-shaped, with one end of the L-shape being a positioning claw 32 and the other end located in a hole 101 provided on the positioning frame 1. A first spring 31 is provided in the hole 101, allowing the slider 3 to automatically reset / position under the elastic force of the first spring 31. The pulling mechanism 2 includes multiple pull blocks 21, each located between pairs of sliders 3. The pull blocks 21 are used to drive the pairs of sliders 3 to separate from each other. Specifically, the surface of the pull block 21 that contacts the slider 3 is an inclined surface or a curved surface, so that the pull block 21 can change the distance between the pairs of sliders 3 when it moves. When the pulling mechanism is released, the pull block 21 can automatically reset under the cooperation of the inclined surface or curved surface and the first spring 31 and the second spring 13, and at the same time, the distance between the pairs of sliders 3 can also be reduced, thus positioning the encapsulated body 5.
[0023] like Figure 1-4 As shown, the pulling mechanism 2 includes a movable plate 20, and the pull block 21 is connected to the movable plate 20; the movable plate 20 is movably connected to the positioning frame 1. Both ends of the movable plate 20 are connected to the positioning frame 1 via equal-height screws 14. A second spring 13 is provided on the screw of the equal-height screw 14, and the second spring 13 is located between the movable plate 20 and the head of the equal-height screw 14. When the pulling mechanism 2 is released, the second spring 13 causes the movable plate 20 to reset, thereby driving the pull block 21 to reset, and simultaneously reducing the distance between the paired sliders 3, thus positioning the encapsulated body.
[0024] Additionally, the movable plate 20 is provided with pins 22 for positioning the entire positioning mechanism. Screws 23 are provided on the movable plate 20 for pulling it. Positioning pins 12 are provided on the positioning frame 1, extending downwards outside the positioning frame 1 for positioning the power module. A cover plate 4 is provided on the positioning frame 1, covering the slider 3.
[0025] The working principle of this utility model is as follows:
[0026] like Figure 1 and 2 As shown, in the initial state, the positioning frame 1 is placed on the heat dissipation substrate 6, and then three plastic encapsulation bodies 5 are placed in sequence. At this time, there can be a gap of 0.05mm between the positioning mechanism and the plastic encapsulation body 5 to facilitate placement. Then, it is sent into the reflow oven for heating and welding.
[0027] After welding is completed and cooled, pull the pulling mechanism 2 with both hands. At this time, the slider 3 is squeezed by the pulling block 21, releasing the plastic seal 5. The entire positioning mechanism is disengaged from the plastic seal 5. Then, remove the positioning mechanism. Figure 4 As shown. When the pulling mechanism 2 is released, it resets due to the action of the second spring 13, and the slider 3 also resets simultaneously due to the action of the first spring 31, as shown. Figure 3As shown.
[0028] This invention, through the positioning of the pulling mechanism 2 and the slider 3, ensures that the encapsulated body is not lifted during the welding process, which would result in uneven weld layer thickness or voids, thereby improving the lifespan of the power module. Through the retraction of the pulling mechanism 2 and the slider 3, it ensures that the encapsulated body will not jam the positioning frame after deformation, which would make disassembly difficult and damage the product, thus improving production yield and efficiency.
[0029] The above description is only a preferred embodiment of the present utility model, but the protection scope of the present utility model is not limited thereto. Any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present utility model should be included within the protection scope of the present utility model.
Claims
1. A welding positioning mechanism for power modules, characterized in that: The system includes a positioning frame (1), on which a positioning mechanism is provided, and the positioning mechanism is connected to a pulling mechanism (2); the positioning mechanism includes multiple pairs of sliders (3), each slider (3) has a positioning claw (32) at one end and the other end located in a hole (101) provided on the positioning frame (1), and a first spring (31) is provided in the hole (101); the pulling mechanism (2) includes multiple pull blocks (21), each pull block (21) being located between the pairs of sliders (3).
2. The welding positioning mechanism for a power module according to claim 1, characterized in that: The surface in contact between the pull block (21) and the slider (3) is an inclined surface or a curved surface.
3. The welding positioning mechanism for a power module according to claim 1, characterized in that: The pulling mechanism (2) includes a movable plate (20), and the pulling block (21) is connected to the movable plate (20); the movable plate (20) is movably connected to the positioning frame (1).
4. The welding positioning mechanism for a power module according to claim 3, characterized in that: The movable plate (20) is connected to the positioning frame (1) at both ends by equal height screws (14). A second spring (13) is provided on the screw of the equal height screw (14). The second spring (13) is located between the movable plate (20) and the head of the equal height screw (14).
5. A welding positioning mechanism for a power module according to claim 3, characterized in that: The movable plate (20) is provided with pins (22).
6. A welding positioning mechanism for a power module according to claim 3, characterized in that: Screws (23) are provided on the movable plate (20).
7. A welding positioning mechanism for a power module according to claim 1, characterized in that: The positioning frame (1) is provided with a positioning pin (12).
8. A welding positioning mechanism for a power module according to claim 1, characterized in that: The positioning frame (1) is provided with a cover plate (4), and the slider (3) is covered by the cover plate (4).