Bottom plate capable of preventing radian change and subfissure
By setting an extension at the top corner of the DBC bottom plate of the IGBT module, stress is dispersed and stress sudden changes are reduced, the radian changes and hidden cracking problems caused by stress concentration during the riveting process in the prior art are solved, and a more uniform stress distribution and structural stability are achieved.
Patent Information
- Application Number
- CN202420930173.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-04-30
- Publication Date
- 2025-03-14
- Estimated Expiration
- 2034-04-30
AI Technical Summary
During the riveting process of the DBC bottom plate of the existing IGBT module, due to changes in shape and space curvature, stress concentration is likely to occur, and radian changes and hidden cracks are prone to occur.
A bottom plate is designed to prevent radian changes and cracks. By providing an extension at the top corner of the plate body, the extension includes a reinforcement rib and an arc-shaped rotation angle, forming a continuous curved shape to disperse stress and reduce stress sudden changes.
Through the design of the extension, the stress originally concentrated at the four corners is dispersed, the degree of stress concentration is reduced, the arc changes and the occurrence of hidden cracks are avoided, and the stress is distributed more evenly at the four corners.
Smart Images
Figure CN222619743U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the field of semiconductor devices, in particular to a bottom plate capable of preventing curvature changes and hidden cracks. Background Art
[0002] An IGBT (Insulated Gate Bipolar Transistor) module is a fully controlled, voltage-driven, composite power semiconductor device consisting of a bipolar transistor and an insulated gate field-effect transistor. The IGBT includes a DBC baseplate, manufactured by directly bonding copper to a ceramic substrate. The DBC baseplate utilizes a special process to bond copper foil directly to the ceramic substrate at high temperatures, achieving a close bond between the metal and ceramic, combining the high electrical conductivity of the metal with the high insulation and thermal stability of the ceramic.
[0003] Currently, DBC chassis and exteriors are typically rectangular. During the riveting process, the four corners of the chassis become structurally distinct points, where the shape and spatial curvature undergo significant changes. This sudden change leads to significant stress concentration in these areas. During the riveting process, when external forces act on the chassis, these sudden changes become the primary stress-bearing areas, causing stress concentration there and potentially leading to curvature changes and hidden cracks.
[0004] It should be noted that the information disclosed in the above background technology section is only used to enhance the understanding of the background of the present disclosure, and therefore may include information that does not constitute prior art known to ordinary technicians in the field. Utility Model Content
[0005] In view of the deficiencies of the prior art, the utility model discloses a bottom plate which can prevent curvature changes and hidden cracks.
[0006] The technical solutions adopted in this utility model are as follows:
[0007] A base plate for preventing curvature changes and hidden cracks includes a plate body; an extension portion, which is arranged at the top corner of the plate body; the extension portion includes a first reinforcing rib side and a second reinforcing rib side, the first reinforcing rib side is arranged parallel to the end of the long side of the plate body, and the second reinforcing rib side is arranged parallel to the end of the wide side of the plate body.
[0008] Furthermore, a corner 1 is provided at the transition between the reinforcing rib side 1 and the long side of the plate body.
[0009] Furthermore, the first corner is an arc chamfer.
[0010] Furthermore, a second corner is provided at the transition between the second reinforcing rib edge and the wide side of the plate body.
[0011] Furthermore, the second corner is an arc-shaped corner.
[0012] Furthermore, a corner three is provided between the first reinforcing rib side and the second reinforcing rib side.
[0013] Furthermore, the third corner is an arc corner.
[0014] Furthermore, a positioning hole is formed in the extension portion.
[0015] Furthermore, the axial direction of the positioning hole is the thickness direction of the plate.
[0016] The beneficial effects of the utility model are as follows:
[0017] 1. The extension part disperses the stress originally concentrated at the four corners, reducing the degree of stress concentration. The extension part can also serve as a buffer zone to absorb and disperse the stress from external loads, reduce the direct impact on the main structure, and avoid curvature changes and hidden cracks in the bottom plate during the riveting process.
[0018] 2. Corner 1, Corner 2 and Corner 3 are set as arc angles to smoothly transition to right angles and reduce stress mutations caused by right angles, so that stress can be more evenly distributed at the four corners, avoiding cracks or damage caused by stress mutations.
[0019] 3. The corners on the extension form a continuous curve shape, which makes the stress transfer smoother and reduces the structural stress concentration. BRIEF DESCRIPTION OF THE DRAWINGS
[0020] Figure 1 This is a structural diagram of a base plate that prevents curvature changes and hidden cracks.
[0021] Figure 2 This is a schematic diagram of the top view of the base plate processing platform.
[0022] In the figure: 1, plate body; 2, extension part; 21, reinforcing rib side 1; 211, corner 1; 22, reinforcing rib side 2; 221, corner 2; 23, corner 3; 24, positioning hole; 3, rivet ring platform; 31, processing cavity. DETAILED DESCRIPTION
[0023] The specific implementation of the present utility model will be described below with reference to the accompanying drawings.
[0024] In order to make the purpose, technical solution and advantages of the present invention clearer, the device proposed in the present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments. According to the following description, the advantages and features of the present invention will be clearer. It should be noted that the accompanying drawings adopt a very simplified form and use non-precise proportions, which are only used to conveniently and clearly assist in explaining the purpose of the implementation method of the present invention. In order to make the purpose, features and advantages of the present invention more obvious and easy to understand, please refer to the accompanying drawings. It should be noted that the structure, proportion, size, etc. illustrated in the drawings of this specification are only used to match the content disclosed in the specification for people familiar with this technology to understand and read, and are not used to limit the limiting conditions for the implementation of the present invention, so they have no technical substantive significance. Any structural modification, change in proportional relationship or adjustment of size should still fall within the scope of the technical content disclosed in the present invention without affecting the efficacy and purpose that can be achieved by the present invention.
[0025] Example:
[0026] A base plate that prevents curvature changes and hidden cracks, such as Figure 1 As shown, Figure 1 This is a structural schematic diagram of a base plate that prevents curvature changes and hidden cracks, including a plate body 1 and an extension part 2. The plate body 1 is rectangular, and the extension part 2 is arranged at the top corners of the plate body 1. The extension part 2 disperses the stress originally concentrated at the four corners, and the force-bearing area is concentrated on the extension part 2 at the four corners of the plate body 1, thereby avoiding bending and cracking of the plate body 1 due to excessive stress concentration.
[0027] like Figure 1 As shown, the extension portion 2 includes a reinforcing rib 1 21 and a reinforcing rib 2 22. The reinforcing rib 1 21 is arranged parallel to the end of the long side of the plate body 1. A corner 1 211 is provided at the transition between the reinforcing rib 1 21 and the long side of the plate body 1. Corner 1 211 is an arc-shaped chamfer. Compared with a right-angle transition, an arc-shaped transition provides a smoother external curve, making stress transfer smoother and reducing excessive stress concentration. The reinforcing rib 2 22 is arranged parallel to the end of the wide side of the plate body 1, that is, the reinforcing rib 2 22 and the reinforcing rib 1 21 are perpendicular to each other. A corner 3 23 is provided between the reinforcing rib 1 21 and the reinforcing rib 2 22. Corner 3 23 is also an arc-shaped chamfer, completing a smooth transition of the external shape and avoiding stress concentration. The reinforcing rib 2 22 is arranged at the transition between the reinforcing rib 2 22 and the wide side of the plate body 1. Corner 2 221 is an arc-shaped chamfer, which also avoids sharp edges on the outer edge of the extension portion 2 and also avoids excessive structural stress concentration.
[0028] like Figure 1As shown, a positioning hole 24 is opened in the extension part 2. The cross-section of the positioning hole 24 is circular. The axial direction of the positioning hole 24 is the thickness direction of the plate body 1. The positioning hole 24 provides a plug-in position for external parts.
[0029] like Figure 2 The figure shows a top view of the base plate processing platform, which is used to process the rivet ring platform 3 of the base plate to prevent curvature changes and hidden cracks. The top surface of the rivet ring platform 3 is provided with a concave processing cavity 31, the shape of which corresponds to the shape of the base plate. During the riveting process, the processing cavity 31 constrains the plate body 1. Compared with directly placing the plate body 1 on a flat surface for riveting, the plate body 1 does not have a large amount of deformation freedom, which also reduces the risk of curvature changes and hidden cracks in the plate body 1 to a certain extent.
[0030] The technical features of the above-mentioned embodiments can be combined arbitrarily. In order to make the description concise, not all possible combinations of the technical features in the above-mentioned embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.
[0031] The above-described embodiments merely represent several implementations of the present invention. While the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the utility model patent. It should be noted that a person skilled in the art would be able to make various modifications and improvements without departing from the concept of the present invention, and these modifications and improvements fall within the scope of protection of the present invention. Therefore, the scope of protection of the present utility model patent shall be determined by the appended claims.
Claims
1. A base plate for preventing curvature change and hidden cracks, characterized in that: Including board body; comprising an extension portion, wherein the extension portion is arranged at a top corner of the plate body; The extension portion includes a first reinforcing rib side and a second reinforcing rib side. The first reinforcing rib side is arranged in parallel at the end of the long side of the plate body, and the second reinforcing rib side is arranged in parallel at the end of the wide side of the plate body.
2. A base plate for preventing curvature change and hidden cracks according to claim 1, characterized in that: A corner 1 is arranged at a transition point between the reinforcing rib side 1 and the long side of the plate body.
3. A base plate for preventing curvature change and hidden cracks according to claim 2, characterized in that: The first corner is an arc chamfer.
4. The base plate for preventing curvature change and hidden cracks according to claim 1, characterized in that: A second corner is arranged at the transition between the second reinforcing rib edge and the wide side of the plate body.
5. A base plate for preventing curvature change and hidden cracks according to claim 4, characterized in that: The second corner is an arc corner.
6. The bottom plate for preventing curvature change and hidden cracks according to claim 1, characterized in that: A corner three is arranged between the reinforcing rib side one and the reinforcing rib side two.
7. A base plate for preventing curvature change and hidden cracks according to claim 6, characterized in that: The third corner is an arc corner.
8. The base plate for preventing curvature change and hidden cracks according to claim 1, characterized in that: A positioning hole is formed in the extension portion.
9. A base plate for preventing curvature change and hidden cracks according to claim 8, characterized in that: The axial direction of the positioning hole is the thickness direction of the plate body.