Pad of printed circuit board and printed circuit board

Abstract

The utility model discloses a bonding pad of a printed circuit board and the printed circuit board. The bonding pad of the printed circuit board is provided with a slotted hole and a tin penetrating hole communicated with the slotted hole. The slotted hole is used for accommodating the fixed pin for inserting the component, and the unilateral gap between the slotted hole and the fixed pin for inserting the component is recorded as c which is more than or equal to 0.1 mm and less than or equal to 0.2 mm; the tin penetrating holes are located in the side walls and / or corners of the groove holes. The side wall of the slotted hole is matched with the fixing pin of the plug-in component, so that the fixing pin of the plug-in component is kept in the slotted hole, and the plug-in component can be prevented from inclining or even falling off.

Description

Technical Field

[0001] This utility model relates to the field of printed circuit board technology, and in particular to a solder pad for a printed circuit board and a printed circuit board. Background Technology

[0002] Wave soldering is a common process in the soldering of printed circuit board (PCB) assemblies. During the reflow process, especially when entering the ramp section where the PCB contacts the wave after passing through the preheating zone, the PCB is subjected to solder wave impact, vibration, and thermal stress, which can easily cause the through-hole components on the board to tilt, shift, or even completely detach from the pad holes, resulting in poor soldering.

[0003] In related technologies, customized special fixtures are used to support and fix the through-hole components on the printed circuit board. However, the design and manufacturing cost of special fixtures is high, and they are usually dedicated to specific boards, which leads to increased production costs and waste of resources. Utility Model Content

[0004] One object of this invention is to provide a solder pad for a printed circuit board that can solve or at least partially alleviate at least one of the defects in the aforementioned background art.

[0005] Another objective of this invention is to provide a printed circuit board having the aforementioned pads.

[0006] To achieve at least one of the above objectives, the technical solution adopted by this utility model is as follows: a solder pad for a printed circuit board, wherein the solder pad has a slot and a through hole communicating with the slot; the slot is designed to accommodate the fixing foot of an through-hole component, and the single-sided gap between the slot and the fixing foot of the through-hole component is denoted as c, which satisfies: 0.1mm≤c≤0.2mm; the through hole is located on the side wall and / or corner of the slot.

[0007] As a preferred embodiment, the slot is a rectangular hole, and the four corners of the slot are cleaned so that the four side walls of the slot are aligned with the four walls of the fixing feet of the inserted components.

[0008] As a preferred embodiment, the single-sided gap between the slot and the fixing foot of the inserted component is denoted as c, which satisfies: c = 0.15 mm.

[0009] As a preferred embodiment, the distance between two adjacent through holes is denoted as L, which satisfies: L≥0.6mm.

[0010] As a preferred embodiment, the wall of the through-hole is an arc segment.

[0011] As a preferred embodiment, the through-hole includes a first through-hole and a second through-hole. The first through-hole is located on the side wall of the slot, and the second through-hole is located at the corner of the slot. The radius of the wall of the first through-hole is denoted as R1, and the radius of the wall of the second through-hole is denoted as R2, satisfying: R1≥R2.

[0012] As a preferred embodiment, the through-hole includes a first through-hole, which is located on the side wall of the slot. The central angle corresponding to the arc segment of the first through-hole is denoted as α, which satisfies: 150°≤α≤270°.

[0013] As a preferred embodiment, the through hole includes a second through hole, which is located at the corner of the slot. The central angle corresponding to the arc segment of the second through hole is denoted as β, which satisfies: 180°≤β≤330°.

[0014] As a preferred embodiment, the through-hole includes two first through-holes and four second through-holes. The walls of the first through-holes and the walls of the second through-holes form arc segments with equal radii. The first through-holes are located at the midpoint of the long side of the slot, and the center of the first through-hole coincides with the long side of the slot. The second through-holes are located at the corners of the slot, and the center of the second through-hole coincides with the corner of the slot.

[0015] To achieve at least one of the above objectives, the technical solution adopted by this utility model is: a printed circuit board, comprising: the solder pads as described above.

[0016] Compared with the prior art, the beneficial effects of this utility model are as follows:

[0017] (1) The single-sided gap c between the slot and the fixing foot of the inserted component satisfies 0.1mm≤c≤0.2mm. Then, through the cooperation between the side wall of the slot and the fixing foot of the inserted component, the fixing foot of the inserted component is kept in the slot, which helps to prevent the inserted component from tilting or even falling off.

[0018] (2) Through the solder through hole, the solder joint can be made fuller, which helps to avoid solder collapse and overflow, and improves the firmness of the connection between the through-hole components and the solder pad. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of pads according to some embodiments of this application.

[0020] Figure 2 This is a schematic diagram of pads according to other embodiments of this application.

[0021] Figure 3 yes Figure 2 Enlarged view of point A in the middle.

[0022] Figure 4 yes Figure 2 Enlarged view of point B in the middle.

[0023] Figure 5 This is a schematic diagram of pads according to other embodiments of this application.

[0024] Figure 6 yes Figure 5 Enlarged view of point C in the middle.

[0025] In the diagram: 1. Printed circuit board; 10. Pad; 11. Slot; 12. Through hole; 121. First through hole; 122. Second through hole; 13. Pin hole. Detailed Implementation

[0026] The present invention will be further described below with reference to specific embodiments. It should be noted that, without conflict, the various embodiments or technical features described below can be arbitrarily combined to form new embodiments.

[0027] In the description of this utility model, it should be noted that the directional terms such as "center", "lateral", "longitudinal", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", and "counterclockwise" are based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. They should not be construed as limiting the specific protection scope of this utility model.

[0028] It should be noted that the terms "first," "second," etc., in the specification and claims of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence.

[0029] The terms “comprising” and “having”, and any variations thereof, in the specification and claims of this application are intended to cover non-exclusive inclusion, for example, a process, method, system, product, or device 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 device.

[0030] A solder pad 10 of a printed circuit board 1, such as Figures 1-6As shown, the pad 10 has a slot 11 and a through hole 12 communicating with the slot 11; the slot 11 can accommodate the fixing foot of the through component, and the single-sided gap between the slot 11 and the fixing foot of the through component is denoted as c, which satisfies: 0.1mm≤c≤0.2mm; the through hole 12 is located on the side wall and / or corner of the slot 11.

[0031] It should be understood that the single-sided gap c between the slot 11 and the fixing foot of the through-hole component satisfies 0.1mm≤c≤0.2mm. Thus, through the cooperation between the sidewall of the slot 11 and the fixing foot of the through-hole component, the fixing foot of the through-hole component is kept within the slot 11, which helps to prevent the through-hole component from tilting or even falling off. In other words, in this embodiment, the through-hole component is fixed by the cooperation between the sidewall of the slot 11 and the fixing foot of the through-hole component; thus, the through-hole component no longer needs to be supported and fixed using customized special fixtures, thereby reducing the use of special fixtures, or even eliminating the need for them, thereby reducing production costs; in addition, it can simplify or even eliminate the step of removing the special fixture from the printed circuit board 1, thereby improving production efficiency.

[0032] Furthermore, during the reflow process, the solder through the through-hole 12 allows the solder to penetrate from the BOT side (bottom surface) to the TOP side (top surface) of the printed circuit board 1, thereby improving the solder joint fullness on the TOP side of the printed circuit board 1, forming solder joints with higher mechanical strength, and improving the tightness and reliability of the solder joint connection. In addition, the through-hole 12 facilitates the expulsion of gas from the solder, reduces the porosity inside the solder joint, makes the solder joint fuller, and helps to avoid solder collapse and overflow. It is worth mentioning that after the solder in the through-hole 12 solidifies, it forms a rivet-like structure to play a mechanical interlocking role, improving the firmness of the connection between the through-hole components and the pads 10.

[0033] Specifically, if the single-sided gap c between the slot 11 and the fixing pin of the through-hole component is greater than 0.2 mm, the through-hole component may be displaced due to vibration or the slope during the wave soldering process, causing the fixing pin of the through-hole component to detach from the slot 11. Furthermore, excessive solder may flow into the slot 11, resulting in excessive solder slag or short circuits on the soldering surface, thus affecting the yield of the printed circuit board 1. If the single-sided gap c between the slot 11 and the fixing pin of the through-hole component is less than 0.1 mm, it will increase the difficulty of inserting the fixing pin of the through-hole component into the slot 11, especially if the slot 11 is too small due to processing errors, thus reducing the production efficiency of the printed circuit board 1. In this embodiment, the single-sided gap c between the slot 11 and the fixing pin of the through-hole component satisfies 0.1 mm ≤ c ≤ 0.2 mm, which is beneficial for ensuring the efficiency of inserting and installing the through-hole component to the pad 10, and also improves the reliability of soldering the through-hole component to the pad 10.

[0034] In at least one embodiment, the single-sided gap c between the slot 11 and the fixing foot of the through-hole component satisfies c=0.15mm. This setting allows the fixing foot of the through-hole component to be easily inserted into the slot 11, and also allows for a better capillary effect on the rise of the solder through the gap.

[0035] It is worth mentioning that, in addition to the mounting feet for inserting components, slot 11 can also accommodate the housing of inserting components, and this application does not impose any specific restrictions on this.

[0036] In some embodiments, the slot 11 is a rectangular hole, and the four corners of the slot 11 are cleared so that the four sidewalls of the slot 11 are aligned with the four walls of the mounting feet of the through-hole component. It should be understood that by clearing the four corners of the slot 11, the corners of the slot 11 can be made closer to sharp corners or even right angles. In other words, the slot 11 is made closer to a rectangular hole than an oblong hole, so that the distance between the four walls of the mounting feet of the through-hole component and the hole wall of the slot 11 is more consistent. This is conducive to the uniform rise of solder to form symmetrical and reliable solder joints, and improves the reliability of the soldering between the through-hole component and the pad 10.

[0037] In some embodiments, such as Figure 1 and Figure 5 As shown, the distance between two adjacent through-holes 12 is denoted as L, which satisfies: L ≥ 0.6 mm. Here, L is the minimum distance between two adjacent through-holes 12. It should be understood that opening through-holes 12 reduces the area of ​​the copper foil layer in the printed circuit board 1. If the distance L between two adjacent through-holes 12 is less than 0.6 mm, the strength of the copper foil layer may be lower, thereby increasing the risk of cracking of the printed circuit board 1 due to mechanical or thermal stress. In this embodiment, the distance L between two adjacent through-holes 12 is ≥ 0.6 mm, which reduces the impact on the copper foil layer, allowing the printed circuit board 1 to maintain high structural strength. Furthermore, retaining sufficient copper foil area enables the printed circuit board 1 to maintain a relatively stable current carrying capacity.

[0038] In some embodiments, such as Figures 1-6 As shown, the wall of the through-hole 12 is an arc segment. It should be understood that this design helps to distribute stress evenly around the through-hole 12, thereby reducing the risk of cracks in the pad 10 due to stress concentration, and improving the structural strength and reliability of the pad 10 and the printed circuit board 1. It is worth mentioning that the arc segment of the through-hole 12's wall also helps to reduce the processing difficulty of the through-hole 12. In other words, the through-hole 12 can be obtained through drilling, and different diameters of through-hole 12 can be obtained using different drill bits, thereby reducing the processing difficulty and cost of the pad 10. Furthermore, the arc-shaped hole wall reduces flow resistance, which is beneficial for the rise of the solder.

[0039] In at least one embodiment, the processing steps of the pad 10 are as follows: first, drill through holes 12, then mill slot holes 11, and finally fine mill slot holes 11 and through holes 12 to remove burrs, thereby making the hole walls of slot holes 11 and through holes 12 smoother, so as to reduce flow resistance, facilitate the rise and penetration of solder, and improve the soldering reliability of through-hole components and pad 10.

[0040] In some embodiments, such as Figure 3 , Figure 4 and Figure 6 As shown, the through-hole 12 includes a first through-hole 121 and a second through-hole 122. The first through-hole 121 is located on the side wall of the slot 11, and the second through-hole 122 is located at the corner of the slot 11. The radius of the hole wall of the first through-hole 121 is denoted as R1, and the radius of the hole wall of the second through-hole 122 is denoted as R2, satisfying: R1≥R2. It should be understood that the side wall of the slot 11, especially the long side, has a large space. Therefore, while avoiding the pin holes 13 on the pad 10, the radius R1 of the first through-hole 121 can be set to be relatively large, so that the solder rises faster during wave soldering, which is beneficial to ensuring the soldering strength between the through-hole components and the pad 10. Furthermore, the space at the corner of the slot 11 is limited, so the radius R2 of the second through-hole 122 can be set to be relatively small, which can both achieve the function of solder penetration and avoid having a significant impact on the structural strength of the pad 10. It is worth mentioning that the first through hole 121 can be located on the short side of the slot hole 11 or on the long side of the slot hole 11. This application does not impose any specific restrictions on this.

[0041] In some embodiments, such as Figure 3 and Figure 6 As shown, the through-hole 12 includes a first through-hole 121, which is located on the sidewall of the slot 11. The central angle corresponding to the arc segment of the first through-hole 121 is denoted as α, satisfying: 150°≤α≤270°. Specifically, when α=180°, the center of the first through-hole 121 is located on the sidewall of the slot 11; when 150°≤α<180°, the center of the first through-hole 121 is located within the area of ​​the slot 11; and when 180°<α≤270°, the center of the first through-hole 121 is located outside the area of ​​the slot 11. It should be understood that when the central angle α corresponding to the arc segment of the first through hole 121 satisfies 150°≤α≤270°, it can provide a larger through hole channel and help avoid the connection between the solder in the first through hole 121 and the solder in the slot 11 being too weak, thereby improving the soldering reliability between the through-hole components and the pad 10.

[0042] In some embodiments, such as Figure 4 and Figure 6As shown, the through-hole 12 includes a second through-hole 122, which is located at the corner of the slot 11. The central angle corresponding to the arc segment of the second through-hole 122 is denoted as β, satisfying: 180°≤β≤330°. Specifically, when β=180°, the wall of the second through-hole 122 coincides with the corner of the slot 11; when 180°<β<270°, the center of the second through-hole 122 is located within the area of ​​the slot 11; when β=270°, the center of the second through-hole 122 coincides with the corner of the slot 11; and when 270°<β≤330°, the center of the second through-hole 122 is located outside the area of ​​the slot 11. It should be understood that when the central angle corresponding to the arc segment of the second through hole 122 is denoted as β, which satisfies 180°≤β≤330°, it can provide a larger through hole channel and help avoid the connection between the solder in the second through hole 122 and the solder in the slot 11 being too weak, thereby improving the soldering reliability between the through-hole components and the pad 10.

[0043] In some embodiments, such as Figure 1 As shown, the through-hole 12 includes two first through-holes 121 and four second through-holes 122. The walls of the first through-holes 121 and the second through-holes 122 are arc segments with equal radii, simplifying the selection of drill bits or milling cutters and reducing the processing complexity of the pads 10. Furthermore, the first through-holes 121 are located at the midpoint of the long side of the slot 11, and the center of the first through-hole 121 coincides with the long side of the slot 11. The second through-holes 122 are located at the corners of the slot 11, and the center of the second through-hole 122 coincides with the corner of the slot 11. It should be understood that the symmetrical arrangement of the two first through-holes 121 and the four second through-holes 122 facilitates uniform and synchronous solder pressure rise, and after the solder cools, results in a more stable and uniform stress distribution between the through-hole components and the pads 10, reducing stress concentration and improving soldering yield.

[0044] It is worth mentioning that the second through hole 122 is opened at the corner of the slot 11 to avoid the fixing feet of the through-hole components. When processing the pad 10, drilling the second through hole 122 can replace the corner clearing process, which can further simplify the selection of drill bit or milling cutter, thereby improving the processing efficiency of the pad 10 and facilitating the automated production of the printed circuit board 1.

[0045] A printed circuit board 1, such as Figures 1-6 As shown, including the aforementioned pads 10, the soldering between the through-hole components and the printed circuit board 1 is made more robust, the electrical connection is more reliable, thereby improving the vibration resistance, shock resistance, and long-term stability of the final product.

[0046] The basic principles, main features, and advantages of this utility model have been described above. Those skilled in the art should understand that this utility model is not limited to the above embodiments. The embodiments and descriptions in the specification are merely the principles of this utility model. Various changes and modifications can be made to this utility model without departing from its spirit and scope, and all such changes and modifications fall within the scope of the claimed utility model. The scope of protection of this utility model is defined by the appended claims and their equivalents.

Claims

1. A solder pad for a printed circuit board, characterized in that, The pad has a slot and a through hole communicating with the slot; the slot is designed to accommodate the mounting feet of through-hole components, and the single-sided gap between the slot and the mounting feet of the through-hole components is denoted as c, which satisfies: 0.1mm≤c≤0.2mm; the through hole is located on the side wall and / or corner of the slot.

2. The pad according to claim 1, characterized in that, The slot is a rectangular hole, and the four corners of the slot are cleaned so that the four side walls of the slot are aligned with the four walls of the mounting feet of the inserted components.

3. The pad according to any one of claims 1-2, characterized in that, The single-sided gap between the slot and the fixing foot of the inserted component is denoted as c, which satisfies: c = 0.15 mm.

4. The pad according to any one of claims 1-2, characterized in that, The distance between two adjacent through holes is denoted as L, which satisfies: L≥0.6mm.

5. The pad according to any one of claims 1-2, characterized in that, The wall of the through-hole is an arc segment.

6. The pad according to claim 5, characterized in that, The through-hole includes a first through-hole and a second through-hole. The first through-hole is located on the side wall of the slot, and the second through-hole is located at the corner of the slot. The radius of the wall of the first through-hole is denoted as R1, and the radius of the wall of the second through-hole is denoted as R2, satisfying: R1≥R2.

7. The pad according to claim 5, characterized in that, The through-hole includes a first through-hole, which is located on the side wall of the slot. The central angle corresponding to the arc segment of the first through-hole is denoted as α, which satisfies: 150°≤α≤270°.

8. The pad according to claim 5, characterized in that, The through-hole includes a second through-hole, which is located at the corner of the slot. The central angle corresponding to the arc segment of the second through-hole is denoted as β, which satisfies: 180°≤β≤330°.

9. The pad according to claim 2, characterized in that, The through-hole includes two first through-holes and four second through-holes. The walls of the first through-holes and the walls of the second through-holes form arc segments with equal radii. The first through-holes are located at the midpoint of the long side of the slot, and the center of the first through-hole coincides with the long side of the slot. The second through-holes are located at the corners of the slot, and the center of the second through-hole coincides with the corner of the slot.

10. A printed circuit board, characterized in that, include: The pads as described in any one of claims 1-9.

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