Crimping structure of IGBT module, crimping die and power module
By designing heat-conducting material protection holes and limiting grooves in the pressing mold, multiple IGBT modules can be pressed simultaneously, solving the problems of high welding costs and damage caused by multiple pressings in the existing technology, and improving pressing efficiency and reliability.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- BEIJING XINGAN TECH CO LTD
- Filing Date
- 2025-05-21
- Publication Date
- 2026-05-19
AI Technical Summary
In the existing technology, the welding cost of IGBT modules is high and the efficiency is low. Multiple pressing causes deformation of PCB board and other electronic components and damage to thermal conductive materials. Moreover, it is difficult to press multiple modules at the same time.
The design employs a pressing mold, with protective holes for thermal conductive material and limiting grooves. Positioning guide posts are used for positioning, enabling multiple IGBT modules to be pressed together at one time, thus avoiding damage to the modules from the thermal conductive material.
It improves crimping efficiency, reduces labor time by more than 60%, achieves positioning accuracy of ±0.02mm, and ensures 100% alignment between solder feet and PCB pads, thereby enhancing the reliability of the module and its stability after installation.
Smart Images
Figure CN224265212U_ABST
Abstract
Description
Technical Field
[0001] This application belongs to the field of microelectronics technology, and specifically relates to a pressing structure, pressing mold and power module of an IGBT module. Background Technology
[0002] Power modules are widely used in products ranging from industrial equipment to home appliances, public transportation, and information terminals. During the production process, power modules require the soldering and assembly of PCB boards and IGBT modules.
[0003] Currently, the common assembly process for PCBs and IGBT modules in automotive controllers is manual soldering. Manual soldering is costly and inefficient, and the PCB is exposed to risks from temperature shocks and mechanical deformation. Furthermore, with the introduction and implementation of RoHS standards, the temperature requirements for lead-free soldering will be even higher, making it more difficult to control the quality of manual soldering, and repair and disassembly are extremely cumbersome.
[0004] To address the aforementioned issues, existing technologies, such as the PCB-based IGBT module and heat sink installation method disclosed in CN114828442A, involve pre-coating the IGBT module with PCM material (phase change material) before installation. However, since PCM itself has thickness and is solid at room temperature, the PCM material directly contacts the IGBT module's backing plate during the press-fitting process. Under pressure, this can easily cause the ceramic layer in the module's backing plate to crack, resulting in insulation withstand voltage failure.
[0005] After the module with pre-coated PCM material is installed, the PCM material does not melt and spread evenly on the module mounting surface because it has not been baked. As the module is used, the PCM material gradually melts and the thickness after spreading becomes smaller. This causes the bolt installation force for locking the module to be much less than the normally recommended installation torque. At this time, the module is prone to movement and failure when exposed to vibration.
[0006] Furthermore, current technology can only crimp one IGBT module at a time. When there are multiple modules on a PCB board, only one module can be crimped multiple times, and the position needs to be repeatedly calibrated. At the same time, multiple crimping can easily cause deformation and breakage of the PCB board and other electronic components on it. In addition, the PCM material on the module being crimped first can also be damaged and contaminated during the multiple crimping process.
[0007] Therefore, there is an urgent need for a new technical solution for IGBT module crimping that can solve the above problems. Utility Model Content
[0008] To address the shortcomings of the prior art, this application provides a pressing structure, pressing mold, and power module for IGBT modules, which not only enables simultaneous pressing of multiple IGBT modules but also avoids damage to thermally conductive materials and improves reliability.
[0009] The technical effect to be achieved in this application is accomplished through the following solution:
[0010] According to a first aspect of this application, a pressing structure for an IGBT module is provided, comprising, from bottom to top, a pressing mold, an IGBT module, and a PCB board. The pressing mold is provided with a plurality of pressing positions, the number and position of which correspond to the number and position of the IGBT module. Each pressing position is provided with a matrix arrangement of thermally conductive material protective holes, and the bottom of the IGBT module is coated with thermally conductive material.
[0011] Preferably, the pressing mold is provided with a limiting groove, the size of which is adapted to the PCB board, and the depth of which is adapted to the thickness of the IGBT module.
[0012] Preferably, the device further includes a positioning guide post. The pressing mold is provided with corresponding module positioning holes. The positioning guide post passes through the heat sink screw fixing holes on the PCB board and the mounting holes on both sides of the IGBT module in sequence and is then inserted into the module positioning hole for positioning.
[0013] Preferably, the crimping recess forms a module limiting surface, the size of which is consistent with the height of the protruding mounting hole below the IGBT module, and the heat-conducting material protection hole is disposed in the module limiting surface.
[0014] Preferably, the top of the positioning guide post is enlarged to form a limiting part, and the diameter of the limiting part is larger than the radiator screw fixing hole.
[0015] Preferably, the shape of the protective hole in the thermally conductive material is one of a circle, an ellipse, or a polygon.
[0016] Preferably, the diameter of the protective hole in the thermally conductive material is 1mm to 10mm.
[0017] Preferably, the PCB board is provided with a matrix of crimp holes that match the pins of the IGBT module.
[0018] According to a second aspect of this application, a crimping mold for an IGBT module is provided. The crimping mold has a plurality of crimping positions, the number and position of which are consistent with the number of IGBT modules to be crimped on a single PCB board. The crimping positions are provided with thermally conductive material protective holes arranged in a matrix.
[0019] According to a third aspect of this application, a power module is provided, which is formed by pressing together the aforementioned IGBT module using a pressing structure.
[0020] According to one embodiment of this application, the beneficial effects of using the crimping structure of this IGBT module are as follows:
[0021] By setting up protective holes for thermal conductive materials, the thermal conductive material at the bottom of the IGBT module will enter the protective holes during crimping. The crimping force will only act on the solder feet and the PCB board, and the thermal conductive material of the IGBT module will not be squeezed or damaged.
[0022] Multiple IGBT modules can be crimped together in one go, reducing the time by more than 60%; moreover, the yield rate is improved, the positioning accuracy reaches ±0.02mm, and the solder feet are 100% aligned with the PCB pads;
[0023] Because the thermally conductive material is located in the protective hole of the thermally conductive material, the installation process will not squeeze the insulation material of the IGBT module, thus avoiding the insulation withstand voltage failure of the IGBT module; moreover, the thermally conductive material is located in the protective hole of the thermally conductive material, and its thermal deformation will not cause a decrease in bolt torque after installation, thus improving reliability. Attached Figure Description
[0024] To more clearly illustrate the embodiments of this application or the existing technical solutions, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0025] Figure 1 This is a schematic diagram of the crimping structure of an IGBT module according to an embodiment of this application;
[0026] Figure 2 for Figure 1 A cross-sectional view of the IGBT module after crimping.
[0027] Figure 3 for Figure 1 Schematic diagram of the structure at the medium-pressure connection point;
[0028] Figure 4 for Figure 1 A schematic diagram of the structure of the IGBT module;
[0029] Figure 5 for Figure 1 A schematic diagram of the positioning guide post. Detailed Implementation
[0030] To make the objectives, technical solutions, and advantages of this application clearer, the technical solutions of this application will be clearly and completely described below in conjunction with specific embodiments and corresponding drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of them. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.
[0031] like Figures 1 to 5 As shown, an embodiment of this application discloses a crimping structure for an IGBT module, comprising, from bottom to top, a crimping mold 100, an IGBT module 200, and a PCB board 300. The crimping mold 100 has a plurality of crimping positions 101, the number and position of which correspond to those of the IGBT module 200. Each crimping position 101 has a matrix of thermally conductive material protective holes 121. The bottom of the IGBT module 200 is coated with a thermally conductive material 110. The PCB board 300 has a matrix 301 of crimping holes that match the pins 220 of the IGBT module 200.
[0032] The thermally conductive material 110, or TIM (Thermal Interface Material), is a material used to fill the microscopic gaps between two solid surfaces (such as a chip and a heat sink) to improve heat conduction efficiency and solve the interface thermal resistance problem caused by air (which has extremely poor thermal conductivity).
[0033] Examples include PCM materials (phase change materials), thermal grease, thermal pads, metal-based TIM, graphene TIM, etc. In this embodiment, PCM materials are used.
[0034] The thermal conductive material protection hole 121 is provided so that the thermal conductive material 110 at the bottom of the IGBT module 200 can enter the thermal conductive material protection hole 121 during the crimping process. The crimping force is only applied to the solder feet and the PCB board 300. The thermal conductive material 110 of the IGBT module 200 is not squeezed and will not be damaged.
[0035] Multiple IGBT modules can be crimped together in one go, reducing the time by more than 60%; moreover, the yield rate is improved, the positioning accuracy reaches ±0.02mm, and the solder feet are 100% aligned with the PCB pads;
[0036] Since the thermally conductive material 110 is located in the thermally conductive material protection hole 121, the installation process will not squeeze the insulation material of the IGBT module 200, thus avoiding the insulation withstand voltage failure of the IGBT module 200; moreover, since the thermally conductive material 110 is located in the thermally conductive material protection hole 121, its thermal deformation will not cause a decrease in bolt torque after installation, thus improving reliability.
[0037] In one embodiment of this application, a limiting groove 130 is provided in the crimping mold 100. The size of the limiting groove 130 is adapted to the PCB board 300, and the depth of the limiting groove 130 is adapted to the thickness of the IGBT module 200. The limiting groove 130 and the PCB board 300 adopt a structural design adapted to the printed PCM stencil, which evenly distributes pressure during crimping and prevents damage to the heat-conducting material 110.
[0038] The limiting groove 130 can limit the position of the PCB board 300, ensuring that it is accurately pressed together with the IGBT module 200 during pressing, thus improving accuracy.
[0039] In one embodiment of this application, a positioning guide post 310 is further included. The pressing mold 100 has corresponding module positioning holes 140. The positioning guide post 310 passes sequentially through the heat sink screw fixing holes 302 on the PCB board 300 and the mounting holes 210 on both sides of the IGBT module 200 before being inserted into the module positioning hole 140 for positioning. The top of the positioning guide post 310 is enlarged to form a limiting part, the diameter of which is larger than the heat sink screw fixing hole 302.
[0040] The positioning guide post 310 positions the PCB board 300, IGBT module 200 and pressing mold 100. The gap between the mounting hole 210 and the positioning hole 140 is ≤0.05mm to ensure that the module position is fixed and without offset.
[0041] In one embodiment of this application, the crimping position 101 is recessed to form a module limiting surface 120. The size of the module limiting surface 120 is consistent with the height of the protruding mounting hole 210 below the IGBT module 200. A heat-conducting material protection hole 121 is provided in the module limiting surface 120. This prevents the IGBT module 200 from being deformed under force during crimping, thus avoiding affecting the yield rate.
[0042] In one embodiment of this application, the shape of the heat-conducting material protective hole 121 is one of a circle, an ellipse, or a polygon. The diameter is 1mm to 10mm.
[0043] The pressing die 100 itself can be made of copper, aluminum, or copper-aluminum composite material, and can be surface treated with electroplating silver, nickel, or bare metal. The limiting groove 130 can be formed by cutting a groove, or it can be a groove formed by setting a limiting ring around the pressing die 100. The limiting ring is made of materials such as NOMEX, NMN, DMD, PI, PVF, PET, etc.
[0044] When using this structure, the specific steps for simultaneously crimping three IGBT modules without copper substrates are as follows:
[0045] Step 1: Place the three IGBT modules into the pressing mold in sequence, and use the limiting surface to fix the X and Y axes of the IGBT modules.
[0046] Step 2: Align the pins of the PCB board with the pins of the IGBT module using the positioning guide post, and place the PCB board into the pressing mold so that the positioning guide post is inserted into the corresponding positioning hole;
[0047] Step 3: Use an automatic crimping machine to complete the crimping in one go. The crimping machine pressure is set to 1-20MPa, the crimping speed should not be less than 25mm / min and not more than 800mm / min, the temperature is 0°-100°C, and the pressure holding time is 1-100s.
[0048] Step 4: After crimping, remove the positioning guide post and the PCB board with the module crimped.
[0049] Step 6: Place the crimped module onto the designed heatsink and pre-tighten it with appropriate bolts. The recommended tightening force is no more than 1.5 Nm.
[0050] Step 7: Place the assembled heat sink, IGBT module, and PCB board into the oven and set the baking parameters to a baking temperature of 30-100℃ and a baking time of 5-100min; preferably 80℃ for 30min in this step to complete the melting of the PCM material and the release of PCB pressure stress.
[0051] Step 8: Install the module normally according to the recommended installation torque.
[0052] This embodiment also discloses a power module, which is formed by pressing together the above-mentioned IGBT module using a pressing structure.
[0053] It should be noted that the above detailed descriptions are exemplary and intended to provide further explanation of this application. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains.
[0054] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments according to this application. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.
[0055] It should be noted that the terms "first," "second," etc., used in the specification, claims, and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such terms can be used interchangeably where appropriate so that the embodiments of this application described herein can be implemented in sequences other than those illustrated or described herein.
[0056] Furthermore, the terms “comprising” and “having”, and any variations thereof, are intended to cover non-exclusive inclusion. For example, a process, method, system, product, or apparatus that includes a series of steps or units is not necessarily limited to those steps or units that are explicitly listed, but may include other steps or units that are not explicitly listed or that are inherent to such process, method, product, or apparatus.
[0057] For ease of description, spatial relative terms such as "above," "on top of," "on the upper surface of," "above," etc., are used herein to describe the spatial positional relationship of a device or feature as shown in the figures to other devices or features. It should be understood that spatial relative terms are intended to encompass different orientations in use or operation beyond the orientation of the device as described in the figures. For example, if the device in the figures were inverted, a device described as "above" or "on top of" other devices or structures would subsequently be positioned as "below" or "under" other devices or structures. Thus, the exemplary term "above" can include both "above" and "below." The device may also be positioned in other different ways, such as rotated 90 degrees or in other orientations, and the spatial relative descriptions used herein will be interpreted accordingly.
[0058] In the detailed description above, reference has been made to the accompanying drawings, which form part of this document. In the drawings, similar symbols typically identify similar parts unless the context otherwise indicates otherwise. The illustrated embodiments described in the detailed specification, drawings, and claims are not intended to be limiting. Other embodiments may be used and other changes may be made without departing from the spirit or scope of the subject matter presented herein.
[0059] The above are merely preferred embodiments of this utility model and are not intended to limit the scope of this utility model. Various modifications and variations can be made to this utility model by those skilled in the art. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of this utility model should be included within the protection scope of this utility model.
Claims
1. A crimping structure for an IGBT module, characterized in that, The components, from bottom to top, include a pressing mold, an IGBT module, and a PCB board. The pressing mold has several pressing positions, the number and position of which correspond to the number of IGBT modules. Each pressing position has a matrix of thermally conductive material protective holes, and the bottom of the IGBT module is coated with thermally conductive material.
2. The crimping structure of the IGBT module according to claim 1, characterized in that, The pressing mold is provided with a limiting groove, the size of which is adapted to the PCB board, and the depth of which is adapted to the thickness of the IGBT module.
3. The crimping structure of the IGBT module according to claim 1, characterized in that, It also includes positioning guide posts. The pressing mold is provided with corresponding module positioning holes. The positioning guide posts pass through the heat sink screw fixing holes on the PCB board and the mounting holes on both sides of the IGBT module in sequence and are then inserted into the module positioning holes for positioning.
4. The crimping structure of the IGBT module according to claim 3, characterized in that, The crimping recess forms a module limiting surface, the size of which is consistent with the height of the protruding mounting hole below the IGBT module, and the heat-conducting material protection hole is disposed in the module limiting surface.
5. The crimping structure of the IGBT module according to claim 3, characterized in that, The top of the positioning guide post is enlarged to form a limiting part, and the diameter of the limiting part is larger than the fixing hole of the radiator screw.
6. The crimping structure of the IGBT module according to claim 1, characterized in that, The shape of the protective hole in the thermally conductive material is one of the following: circular, elliptical, or polygonal.
7. The crimping structure of the IGBT module according to claim 6, characterized in that, The diameter of the protective hole in the thermally conductive material is 1mm to 10mm.
8. The crimping structure of the IGBT module according to claim 1, characterized in that, The PCB board is provided with a matrix of crimp holes that match the pins of the IGBT module.
9. A crimping mold for an IGBT module, characterized in that, The pressing mold is provided with a number of pressing positions, the number and position of which are consistent with the number of IGBT modules to be pressed on the single PCB board, and the pressing positions are provided with thermally conductive material protective holes arranged in a matrix.
10. A power module, characterized in that, It is formed by pressing using the pressing structure of the IGBT module according to any one of claims 1 to 8.