Plug terminal and preparation method and welding method thereof
By introducing a chamfered structure and pre-placed solder balls in the connector, the complexity of soldering separate signal pins is solved, achieving the effect of simplifying the packaging process and improving product reliability.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- SHANGHAI LINZHONG ELECTRONIC TECH CO LTD
- Filing Date
- 2026-01-28
- Publication Date
- 2026-05-15
AI Technical Summary
The existing soldering methods for split signal pins are complex and difficult to control, resulting in low product yield and difficulty in maintaining reliability in harsh environments.
Design a plug terminal including a signal pin and a pin holder. The pin holder has a chamfered structure and pre-installed solder balls. The chamfered structure increases the wetting channel, the pre-installed solder balls simplify the packaging process, and the signal pin and pin holder are integrated by electroplating.
It simplifies the packaging process, improves packaging efficiency and yield, enhances product reliability and stability, and reduces production costs.
Smart Images
Figure CN122051693A_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of power device manufacturing technology, and in particular to a plug-in terminal and its preparation and welding methods. Background Technology
[0002] The motor drive system is a core component of power electronic products. The power module, as a key technology in the motor drive system, is used to achieve precise control of current and voltage, thereby realizing drive and control functions. The reliability of the power module affects the safety and performance of the drive system, and the connection between the signal pins and the circuit board is crucial to ensuring the reliable operation of the power module. Currently, most power modules use split signal pins, consisting of a pin header and a pin. Compared to integrated signal pins, this split design can absorb mechanical stress generated during vibration and other processes, greatly improving the reliability of the entire drive system in harsh environments.
[0003] Currently, in many automotive-grade power modules, the common soldering method for split signal pins is as follows: solder paste is first printed on a copper-clad ceramic substrate, the pin holder is reflow soldered, the flux is cleaned off, and then a pin insertion machine is used to insert the straight pin into the pin holder. In the above soldering method, to prevent the pin holder from being installed backwards and thus unable to insert the pin, the pin holder needs to be made into a through-hole structure. If the amount of solder is too large, too much solder may enter the through hole and cause blockage, resulting in poor pin insertion; if the amount of solder is too small, the shear force of the solder joint of the pin holder is too low, and the solder joint may crack and the pin holder may detach under vibration conditions. It can be seen that the traditional split signal pin has many processes, complex technology, and is difficult to control in the packaging process, which seriously affects the product yield. Therefore, there is an urgent need to find a new split signal pin and packaging process to reduce the production difficulty and improve the product yield. Summary of the Invention
[0004] In view of the shortcomings of the prior art described above, the purpose of this application is to provide a plug-in terminal and its preparation and welding methods, which can improve the reliability of the plug-in terminal, simplify its packaging process, and improve packaging efficiency and output.
[0005] To achieve the above and other related objectives, in a first aspect, this application provides a plug-in terminal, including a signal pin, a pin socket, and pre-filled solder balls; The pin holder includes a base and a pin post. The base has a first surface and a second surface disposed opposite to each other, and an outer surface connecting the first surface and the second surface. The pin post is connected to the first surface of the base and has a pin hole. One end of the signal pin is inserted into the pin hole. The intersection of the first surface and the outer side of the base has a chamfered structure, so that the size of the first surface is smaller than the size of the second surface; The pre-placed solder balls are laid on the outer periphery of the base and at least cover a portion of the second surface of the base. The pre-placed solder balls are used to solder the plug terminals to the soldering area on the surface of the substrate. The surface of the substrate is provided with soldering auxiliary patterns, and the outer contour lines of the soldering auxiliary patterns enclose the soldering area.
[0006] Optionally, both the first surface and the second surface have a circular outer contour line, and the pin post has a cylindrical structure. The radius of the outer contour line of the first surface and the radius of the outer contour line of the second surface have the following relationship: 0.05mm≤R2-R1≤(D2-D3) / 4; where R1 is the radius of the outer contour line of the first surface, R2 and D2 are the radius and diameter of the outer contour line of the second surface, respectively, and D3 is the outer diameter of the pin post.
[0007] Optionally, the thickness of the base is 0.2mm to 0.3mm, and the portion between the plane containing the outer edge line of the chamfered structure on the side close to the second surface and the second surface is referred to as the bottom base, and the thickness of the bottom base is not less than 0.1mm.
[0008] Optionally, the connector further includes a first plating layer and a second plating layer, wherein the first plating layer is applied to the outer surface of the signal pin and the pin holder, and the second plating layer is applied to the first plating layer.
[0009] Optionally, the pin post has a cylindrical structure, and a first annular boss is provided on the outer periphery of the pin post. The thickness of the first annular boss is not less than 0.1 mm and not more than 0.3 mm, and the outer diameter of the first annular boss does not exceed the diameter of the outer contour line of the second surface.
[0010] Optionally, the pin post has a cylindrical structure, the base has a bottom through hole that communicates with the pin hole, and the outer periphery of the pin post has a second annular boss, which is arranged around the end of the pin post away from the base; wherein, the diameter of the bottom through hole does not exceed the diameter of the pin hole.
[0011] Optionally, when viewed from above along the central axis of the pin post, the outer surface of the base has a serrated structure, and the outline of the serrated structure on the outer surface of the base is located between the outer contour of the first surface and the outer contour of the second surface.
[0012] Secondly, this application provides a method for preparing a plug-in terminal, comprising the following steps: Provide needle hub materials and needle body materials; The needle hub material and the needle body material are processed separately to obtain the needle hub and the signal needle; Insert the signal pin into the pin holder; A first plating layer and a second plating layer are sequentially formed on the outer surfaces of the signal needle and the needle holder; Pre-plating of tin is performed on the outer surface of the base to form pre-plated tin balls.
[0013] Thirdly, this application provides a method for soldering plug-in terminals, comprising the following steps: Provides plug-in terminals and substrate; A welding auxiliary pattern is formed on the substrate; The plug-in terminals are assembled into the welding pin clamp; According to the welding auxiliary pattern, the plug terminal is placed in the welding area on the surface of the substrate using the welding pin clamp to weld the plug terminal.
[0014] Optionally, in the step of forming a welding auxiliary pattern on the substrate, the welding auxiliary pattern includes at least one of a solder resist pattern and a positioning pattern, and the plug-in terminal is welded to the welding area enclosed by the solder resist pattern or to the positioning pattern.
[0015] As described above, compared with the prior art, the plug-in terminals, their preparation methods, and welding methods provided in this application have at least the following beneficial effects: Firstly, by setting a chamfered structure, the plug-in terminal can increase the wetting channel for the solder in the subsequent plug-in terminal soldering process, which plays an auxiliary role in solder climbing, allowing the solder to wrap around the base, increasing the amount of solder, and improving the reliability of the product.
[0016] Secondly, the base of the plug-in terminal is covered with pre-filled solder balls, and the processing and assembly of the plug-in terminal can be carried out independently outside the packaging line. The assembled plug-in terminal can be directly soldered, which greatly simplifies the packaging process. Moreover, the assembly of the plug-in terminal can be carried out continuously, which effectively improves packaging efficiency and output and reduces manufacturing costs.
[0017] Thirdly, in the preparation method of the plug-in terminal, after the signal pin and the pin holder are inserted, integrated electroplating can be performed, instead of electroplating the signal pin and the pin holder separately as in the prior art. This reduces the number of process steps, further reduces manufacturing costs, and improves production efficiency. Attached Figure Description
[0018] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.
[0019] Figure 1 The diagram shown is a structural schematic of a plug-in terminal provided in Embodiment 1 of this application.
[0020] Figures 2 to 4 The diagrams show the structures of three different prefabricated patterns in the plug-in terminals provided in Embodiment 1 of this application.
[0021] Figure 5 The diagram shown is a structural schematic of the first annular boss in a plug-in terminal provided in Embodiment 1 of this application.
[0022] Figure 6 The diagram shown is a structural schematic of the second annular boss in a plug-in terminal provided in Embodiment 1 of this application.
[0023] Figure 7 The diagram shown is a schematic diagram of the bottom through hole in a plug terminal provided in Embodiment 1 of this application.
[0024] Figure 8 The diagram shown is a structural schematic of the outer side of the serrated base in a plug terminal provided in Embodiment 1 of this application.
[0025] Figure 9 The image shown is a top view of the outer side of the serrated base in a plug terminal provided in Embodiment 1 of this application.
[0026] Figure 10 The diagram shows the structure after soldering the plug-in terminals in the prior art.
[0027] Figure 11 Displayed as a pair Figure 7 The diagram shows the structure after the plug-in terminals have been soldered.
[0028] Figures 12 to 14 The diagrams show three different types of pre-socketed plug terminals provided in Embodiment 2 of this application.
[0029] Figure 15 The diagram shown is a schematic diagram of the structure after welding the inverted T-shaped plug-in terminal provided in Embodiment 2 of this application.
[0030] Figure 16 The diagram shown is a flowchart illustrating a method for preparing a plug-in terminal according to Embodiment 4 of this application.
[0031] Figure 17 The diagram shown is a schematic flowchart of a welding method for plug-in terminals provided in Embodiment 4 of this application.
[0032] Figures 18 to 20 The diagrams show the structures of three different resist patterns in the welding method provided in Embodiment 4 of this application.
[0033] Figure 21 and Figure 22 These are schematic diagrams showing the positioning patterns formed by grooves and bosses in the welding method provided in Embodiment 4 of this application.
[0034] Illustration of reference numerals in the attached diagram: 10. Connecting terminal; 11. Pin socket; 111. Base; 1111. Bottom through hole; 1112. Pre-formed pattern; 112. Pin post; 1121. Pin hole; 113. First annular boss; 114. Second annular boss; 12. Signal pin; 13. Pre-placed solder ball; 211. Solder mask pattern; 212. Positioning pattern. Detailed Implementation
[0035] To make the technical objectives, technical solutions, and technical effects of this application clearer, the technical solutions in this application will be clearly and completely described below in conjunction with embodiments. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. The components of the embodiments of this application described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.
[0036] Therefore, the following detailed description of embodiments of this application is not intended to limit the scope of the claimed application, but merely to illustrate selected embodiments of the application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without inventive effort are within the scope of protection of this application. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.
[0037] In the description of this application, it should be noted that the terms "center", "longitudinal", "lateral", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", and "outer" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.
[0038] In the description of this application, unless otherwise expressly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly, for example, referring to both fixed connections and detachable connections. Furthermore, the descriptions using terms such as "one embodiment," "some embodiments," "illustrative embodiment," "example," "specific example," or "some examples" indicate that a specific feature, structure, material, or characteristic described in connection with an implementation or example is included in at least one implementation or example of this application. In this specification, illustrative expressions of the above terms do not necessarily refer to the same implementation or example. Moreover, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more implementations or examples.
[0039] In view of the above-mentioned shortcomings mentioned in the background art, firstly, referring to Figures 1 to 9 This invention provides a connector terminal 10, comprising at least a signal pin 12 and a pin holder 11. The pin holder 11 includes a base 111 and a pin post 112. The base 111 has a first surface and a second surface disposed opposite to each other, and an outer surface connecting the first surface and the second surface. The pin post 112 is connected to the first surface of the base 111, and a pin hole 1121 is provided in the pin post 112. One end of the signal pin 12 is inserted into the pin hole 1121. The intersection of the first surface and the outer surface of the base 111 has a chamfered structure, making the size of the first surface smaller than the size of the second surface. In this connector terminal 10, by providing a chamfered structure, a wetting channel can be added for the solder during the subsequent soldering process of the connector terminal 10, which plays a role in assisting solder climbing, allowing the solder to wrap around the base 111, increasing the amount of solder, and improving the reliability of the product.
[0040] Secondly, the present invention provides a method for preparing a plug-in terminal, used to prepare the aforementioned plug-in terminal 10, comprising the following steps: providing a pin holder material and a pin body material; processing the pin holder material and the pin body material respectively to obtain a pin holder 11 and a signal pin 12; inserting the signal pin 12 into the pin holder 11; sequentially forming a first plating layer and a second plating layer on the outer surfaces of the signal pin 12 and the pin holder 11; and pre-plating tin on the outer surface of the base 111 to form pre-plated tin balls 13. In this preparation method, integrated electroplating is performed after the signal pin 12 and the pin holder 11 are inserted, eliminating the need for separate electroplating of the signal pin 12 and the pin holder 11 as required by the prior art, reducing the number of process steps, lowering manufacturing costs, and improving production efficiency.
[0041] Thirdly, the present invention also provides a welding method for a plug-in terminal, used to weld the aforementioned plug-in terminal 10 onto a substrate, comprising the following steps: providing the plug-in terminal 10 and a substrate; forming a welding auxiliary pattern on the substrate; assembling the plug-in terminal 10 into a welding pin clamp; and, according to the welding auxiliary pattern, using the welding pin clamp to place the plug-in terminal 10 in a welding area on the surface of the substrate for welding. In this welding method, the plug-in terminal 10 prefabricated by the present invention can be directly used for the packaging process, simplifying the complex process in the prior art into a "signal pin assembly-welding" process, greatly simplifying the steps of the packaging process, improving packaging efficiency and yield, and reducing production costs.
[0042] To make the solution of the present invention clearer, a detailed description is now provided in conjunction with the following embodiments.
[0043] Example 1 This embodiment provides a plug-in terminal 10, as shown in the reference. Figure 1 The device includes a signal pin 12 and a pin holder 11. The pin holder 11 includes a base 111 and a pin insertion post 112. The base 111 has a first surface and a second surface that are disposed opposite to each other, and an outer surface that connects the first surface and the second surface. The pin insertion post 112 is connected to the first surface of the base 111. A pin hole 1121 is provided in the pin insertion post 112. One end of the signal pin 12 is inserted into the pin hole 1121. The intersection of the first surface and the outer surface of the base 111 has a chamfer structure, so that the size of the first surface is smaller than the size of the second surface.
[0044] In this embodiment, the outer contour lines of both the first and second surfaces are circular, and the pin post 112 is cylindrical, resulting in an inverted T-shaped cross-section for the pin holder 11. The radius R1 of the outer contour line of the first surface and the radius R2 of the outer contour line of the second surface have the following relationship: 0.05mm ≤ R2 - R1 ≤ (D2 - D3) / 4; where D2 is the diameter of the outer contour line of the second surface, and D3 is the outer diameter of the pin post 112. By controlling the dimensional relationship between the radii of the outer contour lines of the first and second surfaces, the dimensions of the chamfer structure can be controlled, preventing excessively large chamfers that increase processing difficulty or excessively small chamfers that reduce the effectiveness of solder joint assistance. This allows the connector 10 in this embodiment to balance the effects of solder joint assistance and ease of processing.
[0045] In this embodiment, the thickness of the base 111 is 0.1mm to 0.3mm, specifically, it can be 0.1mm, 0.2mm, 0.3mm or other suitable thicknesses. The diameter of the base 111 can be set according to actual needs. Optionally, the thickness of the base 111 is 0.2mm to 0.3mm, which can increase the deformation resistance of the soldering area. The part between the plane of the outer edge line of the chamfered structure on the side near the second surface and the second surface is called the bottom base, and the part between the plane of the outer edge line of the chamfered structure on the side near the second surface and the first surface is called the top base. The chamfered structure is located on the outer side of the top base, and the bottom base has a columnar structure. Further, the thickness of the bottom base is not less than 0.1mm, which can simultaneously take into account the auxiliary solder climbing effect and the deformation resistance, thereby improving the reliability of the product.
[0046] In an optional embodiment, for the plug terminal 10 with the inverted T-shaped pin holder 11, the diameter of the outer contour of the second surface of the base 111 is, for example, 1.9 mm and the thickness is, for example, 0.3 mm. The diameter of the pin hole 1121 can be 0.8 mm, the thickness of the bottom base can be 0.1 mm, the difference between the radius R1 of the outer contour of the first surface and the radius R2 of the outer contour of the second surface can be 0.15 mm, the material of the pin holder 11 is, for example, C3604 brass, and the material of the signal pin 12 is, for example, H65 brass.
[0047] In an optional embodiment, a pre-formed pattern 1112 may be provided on the second surface of the base 111, the pre-formed pattern 1112 including a grid pattern (such as... Figure 2 As shown), boss graphics (such as...) Figure 3 As shown), the pitted pattern (such as...) Figure 4 One or more of the following (as shown), wherein the grid pattern can be a raised grid or a recessed grid. By setting a pre-formed pattern 1112 on the second surface of the base 111, the amount of solder on the soldering surface and the area of the soldering surface can be increased, thereby improving the shear resistance of the solder joint.
[0048] In an optional embodiment, refer to Figure 5 The pin post 112 has a cylindrical structure. A first annular boss 113 is provided on the outer periphery of the pin post 112. The first annular boss 113 is located between the axial middle position of the pin post 112 and the first surface of the base 111, so that the pin seat 11 forms an earth-shaped structure. The first annular boss 113 is used to prevent the solder from climbing too high on the outer side of the pin seat 11, so that the amount of solder on the base 111 is reduced and the degree of soldering of the base 111 is reduced. This helps to increase the amount of solder, ensure that the base 111 is wrapped by large solder joints, and improve the reliability of the product.
[0049] Furthermore, the thickness of the first annular boss 113 is not less than 0.1 mm and not more than 0.3 mm, and the outer diameter of the first annular boss 113 does not exceed the diameter of the outer contour line of the second surface, so as to adapt to the limiting design of the solder pin clamp. The specific position, diameter and thickness of the first annular boss 113 can be selected according to the amount of solder and the design of the pin holder 11.
[0050] In an optional embodiment, refer to Figure 6 and Figure 7 The pin post 112 has a cylindrical structure. The base 111 may also be provided with a bottom through hole 1111 that communicates with the pin hole 1121. When in use, the solder will climb onto the side wall surface of the pin hole 1121 through the bottom through hole 1111. A second annular boss 114 is provided on the outer periphery of the pin post 112. The second annular boss 114 is arranged around the end of the pin post 112 away from the base 111, so that the pin seat 11 forms an I-shaped structure.
[0051] The second annular protrusion 114 can absorb the solder that climbs up through the bottom through hole 1111, and spread the solder on the surface of the second annular protrusion 114 to form small solder joints. This can prevent the solder from climbing further onto the signal pin 12 and affecting the subsequent soldering with the circuit board, and can also prevent excessive solder climbing from reducing the amount of solder wrapped around the base 111, ensuring that the pin holder 11 is wrapped by large solder joints, improving the reliability of the product. In addition, the small solder joints can also increase the pull-out force between the signal pin 12 and the pin holder 11, and will not lose the stress relief function due to solder climbing causing the signal pin 12 and the pin holder 11 to be welded together, further improving the reliability of the product.
[0052] Furthermore, the thickness of the second annular boss 114 is not less than 0.1 mm and not more than 0.3 mm, and the outer diameter of the second annular boss 114 does not exceed the diameter of the second surface, so as to adapt to the limiting design of the solder pin clamp. The diameter of the bottom through hole 1111 does not exceed the diameter of the pin hole 1121. The specific value can be set according to the amount of solder.
[0053] Furthermore, for the plug-in terminal 10 of the I-shaped pin header 11, the diameter of the base 111 is, for example, 1.9 mm and the thickness is, for example, 0.2 mm. The diameter of the pin hole 1121 can be 0.7 mm. The base 111 has a frustum structure. The difference between the radius R1 of the first surface and the radius R2 of the second surface can be 0.1 mm. The diameter of the second annular boss 114 is 0.95 mm and the thickness is 0.2 mm. The material of the pin header 11 can be, for example, copper, and the material of the signal pin 12 can be, for example, H65 brass.
[0054] In the projection plane along the central axis of the pin post 112, the outer surface of the base 111 can be a circular structure, or it can be other suitable structures, such as in some alternative embodiments, referring to... Figure 8 and Figure 9 Viewed from above along the central axis of the pin post 112, the outer side of the base 111 has a serrated structure, and the outline of the serrated structure on the outer side of the base 111 is located between the outer outline of the first surface and the outer outline of the second surface, to prevent the serration height of the serrated structure from being too large and reducing the deformation resistance of the welding area.
[0055] The outer surface of the base 111 can have a wavy, serrated structure (such as...). Figure 8 As shown), it can also be a zigzag structure (such as...). Figure 9 As shown, the number of serrations can be, for example, 4, 8, 12, 16, or other suitable numbers, which can be determined according to the dimensions of the base 111. By setting the outer side of the base 111 with a serrated structure, the area of the soldering surface can be increased, and the shear resistance of the solder joint can be improved. Although the surface area of the chamfered structure is reduced, by cooperating with the chamfered structure, the soldering surface area is significantly increased. Compared with the outer side of the cylindrical curved surface structure, the soldering ability can be further enhanced, the amount of solder covering the base 111 can be increased, and the reliability of the product can be improved.
[0056] Figure 10 The diagram shows a schematic of the structure of the plug-in terminal 10 after soldering in the prior art. In the diagram, the base 111 of the plug-in terminal 10 also has a bottom through-hole 1111. The plug-in terminal 10 is soldered using a spot soldering method. Because the surface of the base 111 in this soldered terminal 10 does not have a chamfered structure, the amount of solder covering the base 111 after soldering needs to be further increased. Furthermore, because a second annular boss 114 is not provided, the solder rises through the bottom through-hole 1111 to the outer surface of the signal pin 12 after soldering. Figure 11 A schematic diagram of the structure of the plug terminal 10 with the second annular boss 114 in this embodiment after welding is shown. The solder wraps around the base 111 and spreads on the surface of the second annular boss 114 through the bottom through hole 1111.
[0057] Example 2 This embodiment provides another type of plug-in terminal 10. The similarities with the first embodiment will not be repeated. The difference is that the plug-in terminal 10 in this embodiment also includes pre-planted solder balls 13. The pre-planted solder balls 13 are laid on the outer periphery of the base 111. The pre-planted solder balls 13 are used to solder the plug-in terminal 10 to the soldering area on the surface of the substrate. The surface of the substrate is provided with soldering auxiliary patterns. The outer contour lines of the soldering auxiliary patterns form the soldering area.
[0058] In this embodiment, refer to Figures 12 to 14The pre-planted solder ball 13 at least covers a portion of the second surface of the base 111. Optionally, the pre-planted solder ball 13 may also completely cover the second surface of the base 111, or further cover at least a portion of the side of the base 111, or the pre-planted solder ball 13 may further cover at least a portion of the first surface of the base 111, or the pre-planted solder ball 13 may further cover the first surface of the base 111 and a portion of the outer side of the pin post 112 near one end of the base 111.
[0059] By setting pre-filled solder balls 13, the plug terminal 10 can be directly soldered in subsequent packaging processes, eliminating the need for sequential processes such as solder paste printing, pin mounting, soldering, cleaning, and pin insertion as required in existing technologies. This greatly simplifies the packaging process. Furthermore, the assembly of the signal pin 12 can be performed independently or in advance outside the packaging line, and can continue continuously, effectively improving packaging efficiency and yield while reducing manufacturing costs. In addition, by setting the second annular boss 114, the pin holder 11 forms an I-shaped structure, which effectively improves the mating force between the pin holder 11 and the signal pin 12, increasing the mating force by at least 100%. Moreover, in subsequent packaging processes, the plug terminal 10 of this embodiment can effectively increase the amount of solder, ensuring that the pin holder 11 is wrapped with large solder joints, improving product reliability. Taking a base 111 with a diameter of 1.9mm as an example, the pushing force of the pin holder 11 can reach more than 10kg.
[0060] Figure 15 A schematic diagram of the inverted T-shaped plug terminal 10 after welding is shown. It can be seen that after welding, the plug terminal 10 of this embodiment can effectively increase the amount of solder compared with the prior art, so that the pin seat 11 is wrapped by a large solder joint, which effectively improves the reliability of the product.
[0061] In an optional embodiment, the plug terminal 10 further includes a first plating layer and a second plating layer. The first plating layer is applied to the exposed outer surface of the signal pin 12 and the pin seat 11. The first plating layer can be, for example, a nickel plating layer or other suitable plating layer. Taking a nickel plating layer as an example, the thickness of the nickel plating layer is 2μm to 5μm, specifically, it can be 2μm, 3μm, 4μm, 5μm or other suitable thicknesses. The second plating layer is applied on the first plating layer. The second plating layer can be, for example, a gold plating layer, a tin plating layer or other suitable plating layer. When the second plating layer is a gold plating layer, the thickness of the gold plating layer is not less than 0.0254μm. When the second plating layer is a tin plating layer, the thickness of the tin plating layer does not exceed 5μm.
[0062] Example 3 This embodiment provides a method for preparing a plug-in terminal, used to prepare any type of plug-in terminal 10 of the present invention. In this embodiment, reference is made to... Figure 16 The preparation method includes steps S11 to S15, as detailed below.
[0063] First, step S11 is performed, providing the needle socket material and the needle body material. The materials for the needle socket material and the needle body material can be, for example, copper, copper alloy, or other suitable materials; preferably, the materials for the needle socket material and the needle body material are copper alloys to avoid potential reductions in hardness and strength at high temperatures, which could lead to a decrease in the mating force between the needle socket 11 and the signal needle 12. Optionally, the needle socket material can be, for example, a copper rod, and the needle body material can be, for example, copper wire.
[0064] Next, step S12 is performed to process the needle base material and the needle body material to obtain the needle base 11 and the signal needle 12, respectively. Specifically, taking a copper rod as the needle base material as an example, the needle base material is processed by turning, drilling, deburring and other processes to obtain the needle base 11; taking a copper wire as the needle body material as an example, the needle body material is processed by drawing, straightening, punching and other processes to obtain the signal needle 12.
[0065] In an optional embodiment, the base 111 is provided with a bottom through hole 1111. The step of drilling the needle seat material includes: drilling the needle seat material for the first time to form a needle hole 1121; and drilling the needle seat material for the second time to form the bottom through hole 1111. The drill bit size used in the first and second drilling processes can be specifically set according to the required sizes of the needle hole 1121 and the bottom through hole 1111; for example, the drill bit size in the first drilling process is larger than the drill bit size in the second drilling process.
[0066] Next, step S13 is performed to insert the signal pin 12 into the pin holder 11. Specifically, a pin insertion machine can be used to insert the pin holder 11 and the signal pin 12 together, and a sensor can be used to monitor the insertion force.
[0067] Next, step S14 is performed to sequentially form a first plating layer and a second plating layer on the outer surfaces of the signal pin 12 and the pin holder 11. Taking a nickel plating layer as the first plating layer as an example, an electroplating process can be used to form a nickel plating layer on the exposed outer surfaces of the inserted signal pin 12 and the pin holder 11, and the thickness of the nickel plating layer is controlled to be 2μm~5μm; taking a tin plating layer as the second plating layer as an example, an electroplating process can be used to form a tin plating layer on the surface of the first plating layer, and the thickness of the tin plating layer is controlled to not exceed 5μm.
[0068] Finally, step S15 is performed to pre-plat the base 111 with solder to form pre-plated solder balls 13. Laser plating, solder wire plating, or other suitable plating processes can be used to pre-plat the base 111 with solder.
[0069] In an optional embodiment, laser soldering is used to pre-solder the outer surface of the base 111. Specifically, the ball-separating device in the laser soldering equipment feeds solder balls one by one from the hopper into the guide channel. Each solder ball enters the nozzle from the wire channel and remains at the bottom of the nozzle. The laser beam instantly heats and melts the solder ball. Under the pressure of nitrogen gas, the molten solder is propelled at high speed onto the surface of the base 111. Under the heat of the solder ball and the action of the laser, the solder ball and the base 111 quickly fuse to form a reliable solder joint. At the same time, nitrogen gas continues to act to prevent oxidation of the solder ball and the base 111. Pre-soldering using laser soldering eliminates the need for cleaning, avoids the investment in cleaning equipment and cleaning solution, and saves production costs.
[0070] The plug-in terminal 10 prepared using the preparation method of this embodiment can be directly soldered, which greatly simplifies the packaging process. In addition, the processing and assembly of the plug-in terminal 10 in this preparation method can be carried out independently outside the packaging line of the plug-in terminal 10, or it can be carried out in advance, and the operation can be carried out continuously, which effectively improves the packaging efficiency and output and reduces the manufacturing cost. Furthermore, in the preparation method of this embodiment, after the signal pin 12 is inserted into the pin holder 11, it is electroplated as a whole, which eliminates the need to electroplat the signal pin 12 and the pin holder 11 separately, reducing the number of process steps and further reducing the production cost.
[0071] Example 4 This embodiment provides a method for soldering a plug-in terminal, used to solder any type of plug-in terminal 10 prepared in Embodiment 3 onto a substrate. In this embodiment, reference is made to... Figure 17 The welding method includes steps S21 to S24, as detailed below.
[0072] First, step S21 is performed, providing the plug-in terminal 10 and the substrate. The plug-in terminal 10 is any of the plug-in terminals 10 in the aforementioned embodiment two or three, or any of the plug-in terminals 10 prepared in embodiment four, and the substrate can be, for example, a double-sided copper-clad ceramic substrate.
[0073] Next, step S22 is performed to form a soldering auxiliary pattern on the substrate. The auxiliary soldering pattern is used to assist in the soldering of the plug-in terminal 10, and can limit the solder from wetting the surrounding area during the soldering process, thereby improving the solder creep effect of the plug-in terminal 10 in the present invention during the soldering process.
[0074] In an optional embodiment, in the step of forming a soldering auxiliary pattern on the substrate, the soldering auxiliary pattern includes at least one of a solder resist pattern 211 and a positioning pattern 212. The plug-in terminal 10 is soldered to the soldering area enclosed by the solder resist pattern 211, or soldered to the positioning pattern 212. The solder resist pattern 211 encloses the soldering area of the plug-in terminal 10; see reference... Figure 18The solder mask pattern 211 can be formed by laser solder masking or green solder masking; or refer to Figure 19 It can also be formed by a solder resist groove; or refer to Figure 20 It can also be formed by the tangent of the bonding aluminum wire; the solder mask pattern 211 can prevent solder from wetting areas outside the soldering area. (See reference...) Figure 21 and Figure 22 The positioning pattern 212 is the welding area of the plug-in terminal 10, used to mark the welding position of the plug-in terminal 10. The positioning pattern 212 can be composed of a boss (see reference). Figure 22 ) or groove (refer to) Figure 21 The formation of bosses or grooves can also prevent solder from wetting areas outside the soldering area.
[0075] Furthermore, taking the solder resist pattern 211 formed by green solder resist as an example, after placing the plug terminal 10 on the welding area surrounded by the solder resist pattern 211, the distance between the edge of the solder resist pattern 211 and the base 111 is greater than 0.5mm; taking the positioning pattern 212 formed by the groove as an example, the distance between the edge of the positioning pattern 212 and the base 111 is greater than 0.5mm.
[0076] Next, step S23 is performed to assemble the plug-in terminal 10 into the welding pin holder. Specifically, the assembled plug-in terminal 10 can be automatically assembled into the welding pin holder using a vibratory feeder and a vacuum suction tube.
[0077] Finally, step S24 is performed: according to the welding auxiliary pattern, the plug terminal 10 is placed on the welding area of the substrate surface using a soldering pin holder to weld the plug terminal 10. Specifically, a formic acid furnace or other suitable equipment can be used for welding. The soldering pin holder is placed upside down on the welding fixture, the plug terminal 10 falls, the pre-placed solder balls 13 in the welding terminal contact the substrate, the pre-placed solder balls 13 wrap around the base 111, and climb up the outer side of the pin holder 11.
[0078] In the welding method of this embodiment, the pre-fabricated plug-in terminal 10 of the present invention can be used to directly carry out the packaging process, simplifying the complex process of "printing solder paste-installing pin holder-soldering-cleaning-pin insertion" in the prior art into a process of "signal pin assembly-soldering", which greatly simplifies the steps of the packaging process, improves the efficiency and output of packaging, and reduces production costs. In addition, in the welding method of this embodiment, the auxiliary welding pattern can effectively limit the solder from wetting outside the welding area, ensuring that the welding process has a good solder crawling effect, increasing the amount of solder, ensuring that the pin holder 11 is wrapped by large solder joints, and improving product reliability.
[0079] The above embodiments are merely illustrative of the principles and effects of this application and are not intended to limit this application. Any person skilled in the art can modify, alter, or combine the above embodiments without departing from the spirit and scope of this application. Therefore, all equivalent modifications or alterations made by those skilled in the art without departing from the spirit and technical concept disclosed in this application should still be covered by the claims of this application.
Claims
1. A plug-in terminal, characterized in that, Includes signal pins, pin headers, and pre-filled solder balls; The pin holder includes a base and a pin post. The base has a first surface and a second surface disposed opposite to each other, and an outer surface connecting the first surface and the second surface. The pin post is connected to the first surface of the base and has a pin hole. One end of the signal pin is inserted into the pin hole. The intersection of the first surface and the outer side of the base has a chamfered structure, so that the size of the first surface is smaller than the size of the second surface; The pre-placed solder balls are laid on the outer periphery of the base and at least cover a portion of the second surface of the base. The pre-placed solder balls are used to solder the plug terminals to the soldering area on the surface of the substrate. The surface of the substrate is provided with soldering auxiliary patterns, and the outer contour lines of the soldering auxiliary patterns enclose the soldering area.
2. The plug-in terminal according to claim 1, characterized in that, Both the first surface and the second surface have a circular outer contour line. The pin post has a cylindrical structure. The radius of the outer contour line of the first surface and the radius of the outer contour line of the second surface have the following relationship: 0.05mm≤R2-R1≤(D2-D3) / 4; where R1 is the radius of the outer contour line of the first surface, R2 and D2 are the radius and diameter of the outer contour line of the second surface, respectively, and D3 is the outer diameter of the pin post.
3. The plug-in terminal according to claim 1, characterized in that, The thickness of the base is 0.2mm~0.3mm. The portion between the plane containing the outer edge line of the chamfered structure on the side closest to the second surface and the second surface is referred to as the bottom base. The thickness of the bottom base is not less than 0.1mm.
4. The plug-in terminal according to claim 1, characterized in that, It also includes a first plating layer and a second plating layer, wherein the first plating layer is applied to the outer surface of the signal needle and the needle holder, and the second plating layer is applied on the first plating layer.
5. The plug-in terminal according to claim 1, characterized in that, The insertion pin has a cylindrical structure, and a first annular boss is provided on the outer periphery of the insertion pin. The thickness of the first annular boss is not less than 0.1 mm and not more than 0.3 mm, and the outer diameter of the first annular boss does not exceed the diameter of the outer contour line of the second surface.
6. The plug-in terminal according to claim 1, characterized in that, The insertion pin has a cylindrical structure, and the base has a bottom through hole that communicates with the pin hole. The outer periphery of the insertion pin has a second annular boss, which is located around the end of the insertion pin away from the base. The diameter of the bottom through hole does not exceed the diameter of the pin hole.
7. The plug-in terminal according to claim 1, characterized in that, Viewed from above along the central axis of the insert post, the outer surface of the base has a serrated structure, and the outline of the serrated structure on the outer surface of the base is located between the outer contour of the first surface and the outer contour of the second surface.
8. A method for preparing a plug-in terminal, used to prepare the plug-in terminal according to any one of claims 1 to 7, characterized in that, Includes the following steps: Provide needle hub materials and needle body materials; The needle hub material and the needle body material are processed separately to obtain the needle hub and the signal needle; Insert the signal pin into the pin holder; A first plating layer and a second plating layer are sequentially formed on the outer surfaces of the signal needle and the needle holder; Pre-plating of tin is performed on the outer surface of the base to form pre-plated tin balls.
9. A method for soldering plug-in terminals, characterized in that, Includes the following steps: Provides a substrate and a plug-in terminal as described in any one of claims 1 to 7; A welding auxiliary pattern is formed on the substrate; The plug-in terminals are assembled into the welding pin clamp; According to the welding auxiliary pattern, the plug terminal is placed in the welding area on the surface of the substrate using the welding pin clamp to weld the plug terminal.
10. The welding method according to claim 9, characterized in that, In the step of forming a welding auxiliary pattern on the substrate, the welding auxiliary pattern includes at least one of a solder resist pattern and a positioning pattern, and the plug-in terminal is welded to the welding area enclosed by the solder resist pattern or to the positioning pattern.