A crimping terminal applied to a package

Abstract

The application belongs to the technical field of electronic packaging and specifically discloses a crimping terminal which comprises an elastic needle, a buffer part and a base, wherein the elastic needle has a first outer diameter which is reduced when the elastic needle is deformed under radial pressure; the buffer part is connected below the elastic needle and comprises at least one pair of buffer strips which are in a curved shape and have increased curvature when the buffer strips are subjected to axial pressure; and the base is connected below the buffer part and is in a flat disc shape. The crimping terminal has the advantage that the axial pressure received by the crimping terminal during the crimping process is absorbed and reduced by the buffer part, the force transmitted to a DBC (Direct Bonding Copper) is reduced, and thus the effect of protecting the DBC is achieved.

Description

Technical Field

[0001] This application relates to the field of electronic packaging, and more particularly to a crimp terminal used in packaging. Background Technology

[0002] Currently, the connection terminals (terminals) in power device products are divided into solder terminals and crimp terminals.

[0003] Soldering terminals such as Figure 1 As shown: It consists of two parts: a base (12) and a pin (11). The base at one end of the soldering terminal is connected to the DBC (Direct Bonding Copper) inside the chip by soldering. After the power device is encapsulated in a plastic shell, the soldering terminal is used to connect the power device to the PCB. In order to achieve a good electrical connection, the connection and fixation between the two are usually completed by soldering. The advantages of the soldering terminal are as follows: 1: The connection is stable and reliable, with good stability and reliability, and it is not easy to have poor contact; 2: It can withstand high temperatures; 3: The soldering process is mature and the processing is flexible. Its disadvantages are as follows: 1: The soldering process is irreversible; 2: It is easy to experience fatigue; 3: The process is complicated and the time cost is high.

[0004] Crimp terminals are typically like Figure 2 As shown: It consists of a fisheye (21), a pin (22), an S-bend (24), a support (23), and a base (25). The base is used for welding with the DBC, and the fisheye is used for crimping with the through holes on the PCB. There is a gap between the support and the base, which can serve as a travel distance to offset the excessive deformation caused by the S-bend during crimping and reduce the risk of cracking in the DBC. Its advantages are as follows: 1: Quick and convenient, no pretreatment required, direct installation; 2: High safety, which can effectively reduce the risk of local heating; 3: It can maintain high reliability regardless of high temperature, low temperature, or humid environment. Its disadvantages are as follows: 1: High requirements for the shape of the crimping terminal, with the risk of "knee bending" (pin bending); 2: High requirements for the dimensional consistency of the crimping terminal; 3: Low connection strength. Utility Model Content

[0005] To address the aforementioned issues, this application proposes a crimp terminal for encapsulation, comprising a resilient pin, a buffer portion, and a base. The resilient pin has a first outer diameter, which deforms and shrinks when subjected to radial pressure. The buffer portion, connected below the resilient pin, includes at least one pair of curved buffer strips, whose curvature increases when subjected to axial pressure. The base, connected below the buffer portion, is a flat disc.

[0006] In the aforementioned crimp terminals, the elastic needle is a symmetrical hollow structure or a semi-hollow structure.

[0007] In the aforementioned crimp terminals, the hollow or semi-hollow structure includes fisheye, spindle, spherical, and polyhedral shapes.

[0008] In the aforementioned crimp terminals, the buffer strip includes a first type of buffer strip and a second type of buffer strip. The first type of buffer strip is fixedly connected to both the elastic needle and the base. The second type of buffer strip is slightly shorter than the first type of buffer strip, with one end fixedly connected to the elastic needle and the other end being a free end.

[0009] In the aforementioned crimp terminals, the first type of buffer strip is integrally formed with the elastic needle and the base.

[0010] In the aforementioned crimp terminals, the second type of buffer strip is integrally formed with the elastic needle.

[0011] In the aforementioned crimp terminal, when the elastic needle is subjected to radial pressure, the free end of the second type of buffer strip moves toward the base, abuts against the base, and ultimately forms a resistance opposite to the direction of the radial pressure.

[0012] In the aforementioned crimp terminal, the base further includes a recessed portion located in the middle of the base. The first type of buffer strip is fixed to the bottom surface of the recessed portion, and the free end of the second type of buffer strip is projected onto the bottom surface of the recessed portion.

[0013] In the aforementioned crimp terminals, the upper surface of the base protrudes upwards.

[0014] This application uses only a buffer section to absorb and reduce the axial pressure on the crimp terminal during the crimping process, thereby reducing the force transmitted to the DBC (Direct Bonding Copper) and protecting the DBC. Compared with the prior art, this application eliminates the support body located at the center of the crimp terminal, and instead relies on multiple symmetrically arranged buffer strips in the buffer section to support the overall rigidity (straightness) of the terminal. Furthermore, the opposing buffer strips support the terminal from opposite directions, which can greatly reduce the risk of terminal breakage / bending. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of an existing welding terminal; Figure 2 This is a schematic diagram of an existing crimp terminal; Figure 3 This is a schematic diagram of the first type of crimp terminal proposed according to the embodiments of this application, wherein the elastic pin has a hollow structure; Figure 4 yes Figure 3 Bottom view of the crimp terminal shown; Figure 5 This is a schematic diagram of a second type of crimp terminal according to an embodiment of this application; Figure 6 yes Figure 5 A cross-sectional view of the crimped terminal shown; Figure 7 yes Figure 6 Enlarged view of the area inside the middle circle; Figure 8 This is a schematic diagram of a third type of crimp terminal according to an embodiment of this application; Figure 9 yes Figure 8 A cross-sectional view of the crimped terminal shown; Figure 10 yes Figure 9 Enlarged view of the area inside the middle circle; Figure 11 This is a front view of a semi-hollow elastic needle. Figure 12 yes Figure 11 The diagram shows a cross-section along direction A. Detailed Implementation

[0016] The following specific embodiments illustrate the implementation of this application. Those skilled in the art can easily understand other advantages and effects of this application from the content disclosed in this specification. Although the description of this application is presented in conjunction with preferred embodiments, this does not mean that the features of this application are limited to this embodiment. On the contrary, the purpose of describing the embodiments is to cover other options or modifications that may be derived based on the claims of this application. To provide a thorough understanding of this application, many specific details will be included in the following description. This application may also be implemented without using these details. Furthermore, to avoid confusion or obscuring the focus of this application, some specific details will be omitted in the description. It should be noted that, unless otherwise specified, the embodiments and features in the embodiments of this application can be combined with each other.

[0017] It should be noted that in this specification, similar reference numerals and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures, and is assumed to be the same definition.

[0018] To make the objectives, technical solutions, and advantages of this application clearer, the embodiments of this application will be described in further detail below with reference to the accompanying drawings.

[0019] Crimped terminals (terminals) enable electrical connections in the packaging of electronic components. One end is soldered to the DBC (Direct Bonding Copper) containing the chip, while the other end is crimped into a through-hole of the PCB during assembly, thus achieving electrical / signal connection between the electronic component and the PCB. The axial force generated during crimping is not necessarily perpendicular to the DBC, which can easily cause the support pillars to tilt or even break for crimped terminals with support pillars. This application proposes a crimped terminal that omits the support pillar structure, relying solely on multiple symmetrically arranged buffer strips for cushioning and support.

[0020] Figure 3 This is a schematic diagram of a first type of crimp terminal according to an embodiment of this application. Figure 4 yes Figure 3 The bottom view of the crimp terminal is shown. The flexible pin 31, buffer, and base 34 are visible in both figures.

[0021] The elastic pin 31 has a symmetrical hollow structure with a first outer diameter. When the elastic pin 31 is subjected to radial pressure, it deforms, and the first outer diameter shrinks, allowing the crimp terminal to be smoothly inserted into the through-hole of the PCB, thereby realizing the electrical / signal connection between the electronic components and the PCB. A buffer section is fixedly connected to the elastic pin 31 and includes at least one pair of buffer strips. The buffer strips are curved; when subjected to axial pressure, the curvature of the buffer strips increases, thereby absorbing the axial force and reducing the impact of the axial force on the connection between the base and the DBC. The hollow structure of the elastic pin 31 can include fisheye, spindle, spherical, polyhedral, and other shapes. In some embodiments, the buffer strips can also be integrated with the elastic pin 31.

[0022] The buffer section is subdivided into a first type of buffer strip 33 and a second type of buffer strip 32. The first type of buffer strip 33 is fixedly connected to both the elastic needle 31 and the base 34. When the terminal is subjected to axial force, the first type of buffer strip 33 deforms slightly to absorb and mitigate the axial force. The second type of buffer strip 32 is slightly shorter than the first type of buffer strip 33. One end of the second type of buffer strip 32 is fixedly connected to the elastic needle, and the other end is a free end. When the terminal is subjected to axial force, the second type of buffer strip 32 first moves in the direction of the base 34 until the free end abuts against the base 34. If the axial force is further increased at this time, the first type of buffer strip 33 and the second type of buffer strip 32 can simultaneously generate resistance in the opposite direction to the axial force, thus providing a stronger buffering effect.

[0023] The base 34 can be flat and disc-shaped. The first side of the base 34 is fixedly connected to the DBC by welding or other means, and the second side is fixedly connected to the first type of buffer strip 33 (preferably integrally formed). The free end of the second type of buffer strip 32 approaches the second side of the base 34 under axial pressure until it contacts the second side. Figure 3 and 4 In the embodiment shown, the second surface of the base 34 is a plane, and the contact portion between it and the free end of the second type of buffer strip 32 only includes the end face of the free end, resulting in slightly insufficient stability of the support.

[0024] Figure 5-7 This is another embodiment of the present application. Figure 5 This is a schematic diagram of a second type of crimp terminal according to an embodiment of this application. Figure 6 yes Figure 5 The cross-sectional view of the crimp terminal shown. Figure 7 yes Figure 6 A magnified view of the area inside the middle circle.

[0025] The crimp terminal shown in the figure includes a resilient pin 51, a buffer portion 52, and a base 53. The resilient pin 51 and the buffer portion 52 are similar to those in the previous embodiment and will not be described in detail here. (See reference...) Figure 7 The enlarged detail shown reveals that the base 53, in addition to its flat disc shape, has a recess 532. The recess 532 can be located in the center of the base 53, and preferably its shape is the same as the base 53, and it is concentrically positioned. The size of the recess 532 is preferably sufficient to accommodate the two types of buffer strips in the buffer section 52. For example, the first type of buffer strip can be directly fixed within the recess 532, while the free end of the second type of buffer strip can be suspended in the recess 532 in its free state, meaning the orthogonal projection of the free end onto the base 53 lies within the recess 532. When the crimp terminal is subjected to sufficiently large axial pressure, both the first and second buffer strips undergo significant deformation. The curvature of the first buffer strip increases significantly, while the free end of the second type of buffer strip approaches the bottom surface of the recess and eventually abuts against it, potentially causing it to turn and move towards the center, thus generating reverse resistance to protect the connection between the base and the DBC. Under greater pressure, the sides of the first and second type of buffer strips near the bottom of the recess abut against the upper edge of the recess 532, providing more support force opposite to the pressure direction. Furthermore, the force is evenly distributed in all directions, ensuring the straightness of the crimp terminal and preventing it from "kneeling," thus extending its service life. In this embodiment, the buffer portion 52 receives better support.

[0026] The depth of the recess 532 is determined by the actual usage requirements and the flexibility and support of the material used for the cushioning part. In this case, the upper surface 531 of the base 53 is preferably gradually inclined from the center of the chassis to the edge of the chassis, so as to maintain sufficient thickness at the middle / center position of the chassis, i.e., the bottom surface of the recess 532.

[0027] This embodiment provides more support surface for the buffer section, which helps stabilize the terminal and reduces the risk of the terminal bending after crimping.

[0028] Figure 8-10 A third embodiment of the crimp terminal is then presented. Figure 8 This is a schematic diagram of a third type of crimp terminal according to an embodiment of this application. Figure 9 yes Figure 8 A cross-sectional view of the crimped terminal shown; Figure 10 yes Figure 9 Enlarged view of the portion inside the circle. The crimp terminal shown includes a resilient pin 81, a buffer portion 82, and a base 83. Similarly, the resilient pin 81 and the buffer portion 82 are similar to those in the previous embodiment; both parts can be referred to... Figure 3 The relevant explanations will not be elaborated here. (See references.) Figure 10 As shown in the detailed diagram, the upper surface 831 of the base 83 is convex. The first type of buffer strip of the buffer part 82 is fixed to the upper surface 831, and the second buffer strip only contacts the bottom surface of the second buffer recess 532 when it is subjected to external pressure. As the pressure on the first and second buffer strips gradually increases, the deformation of the first and second buffer strips becomes more and more obvious until their outer surfaces contact the upper surface 831. At this point, the supporting force of the upper surface 831 on the first and second buffer strips also increases simultaneously. Furthermore, since the buffer strips are symmetrically arranged, the stability of the crimp terminal is also ensured.

[0029] Figure 11 This is a front view of a semi-hollow elastic needle. Figure 12 yes Figure 11 The diagram shows a cross-sectional view along direction A. The buffer section 92 and the base 93 are shown in the diagram. Figures 3-10 Similarly, it will not be elaborated here.

[0030] Figure 12 The elastic needle 91 in the middle has a semi-hollow structure, combined with Figure 11 and 12 As shown in the A-direction comparison, the elastic needle 91 in this embodiment, viewed from the front view, is similar to... Figure 3-10 The needles are similar, both having a spindle-shaped outer contour with a hole in the middle to give the needle a certain degree of elasticity. However, from the side, that is... Figure 12As shown in the cross-sectional view along direction A, a reinforcing rib 911 is provided on the inner side of the contour of the elastic needle 91. This rib is located between the inner top of the elastic needle 91 and the connecting portion 94, and its thickness is slightly less than the thickness of the contour of the elastic needle 91. The presence of the reinforcing rib 911 can improve the needle's resistance to radial forces, increase the friction between the needle and the DBC mounting hole, and help improve the installation firmness of the crimp terminal. Similar to previous embodiments, the semi-hollow structure of the elastic needle 91 can also include shapes such as fisheye, spindle, sphere, and polyhedron. In some embodiments, the buffer strip (including the connecting portion 94) can also be integrated with the elastic needle 91.

[0031] It should be noted that numerous specific details are provided in the specification provided in this application. However, it will be understood that embodiments of this application may be implemented without some or all of these specific details. In some instances, well-known methods, structures, and techniques have not been shown in detail so as not to obscure the understanding of this specification.

[0032] Similarly, for the purpose of simplification and to aid in understanding one or more of the aspects, in the above description of exemplary embodiments of the present application, various features of the present application are sometimes grouped together in a single embodiment, figure, or description thereof. However, this approach of disclosure should not be construed as reflecting an intention that the claimed application requires more features than expressly recited in each claim. Rather, as reflected in the claims, the aspects consist of fewer than all features of the single embodiment disclosed above. Therefore, the claims following the detailed description are hereby expressly incorporated into that detailed description, wherein each claim itself is a separate embodiment of the present application.

[0033] Those skilled in the art will understand that modules in the device of the embodiments can be adaptively changed and placed in one or more devices different from that embodiment. Modules, units, or components in the embodiments can be combined into a single module, unit, or component, and further, they can be divided into multiple sub-modules, sub-units, or sub-components. Except where at least some of such features and / or processes or units are mutually exclusive, any combination can be used to combine all features disclosed in this specification (including the accompanying claims, abstract, and drawings) and all processes or units of any method or device so disclosed. Unless expressly stated otherwise, each feature disclosed in this specification (including the accompanying claims, abstract, and drawings) may be replaced by an alternative feature serving the same, equivalent, or similar purpose.

[0034] Furthermore, those skilled in the art should understand that although some embodiments described herein include certain features but not others included in other embodiments, combinations of features from different embodiments are intended to be within the scope of this application and form different embodiments. For example, in the claims, any one of the claimed embodiments can be used in any combination.

Claims

1. A crimp terminal for use in encapsulation, characterized in that, Includes a flexible needle, a buffer section, and a base, among which, The elastic needle has a first outer diameter, which deforms when subjected to radial pressure, causing the first outer diameter to shrink. The buffer section is connected below the elastic needle and includes at least one pair of buffer strips. The buffer strips are curved, and the curvature of the buffer strips increases when the buffer strips are subjected to axial pressure. The base is connected to the buffer section and is flat and disc-shaped.

2. The crimp terminal as described in claim 1, characterized in that, The elastic needle has a symmetrical hollow or semi-hollow structure.

3. The crimp terminal as described in claim 2, characterized in that, The hollow or semi-hollow structure includes fisheye shape, spindle shape, sphere, and polyhedron.

4. The crimp terminal as described in claim 1, characterized in that, The buffer strip includes a first type of buffer strip and a second type of buffer strip. The first type of buffer strip is fixedly connected to both the elastic needle and the base. The second type of buffer strip is slightly shorter than the first type of buffer strip, with one end fixedly connected to the elastic needle and the other end being a free end.

5. The crimp terminal as described in claim 4, characterized in that, The first type of buffer strip is integrally formed with the elastic needle and the base.

6. The crimp terminal as described in claim 4, characterized in that, The second type of buffer strip is integrally formed with the elastic needle.

7. The crimp terminal as described in claim 4, characterized in that, When the elastic needle is subjected to radial pressure, the free end of the second type of buffer strip moves toward the base, abuts against the base, and ultimately forms a resistance in the opposite direction to the radial pressure.

8. The crimp terminal as described in claim 6, characterized in that, The base also includes a recessed portion located in the middle of the base. The first type of buffer strip is fixed to the bottom surface of the recessed portion, and the free end of the second type of buffer strip is projected onto the bottom surface of the recessed portion.

9. The crimp terminal as described in any one of claims 6-8, characterized in that, The upper surface of the base protrudes upwards.

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