PCB with pre-embedded copper blocks

Abstract

The utility model discloses a PCB of preburied copper block, include: the light board of preset inner slot hole, the core plate of being respectively stacked in the light board opposite two side board surface outside, the outer slot hole of being preset on the core plate corresponding inner slot hole place, the prepreg of being located between the light board and the core plate of light board two sides, the intermediate slot hole of being preset on the prepreg, the copper block of being assembled in the inner slot hole and still respectively sequentially passing through the intermediate slot hole and the outer slot hole and being exposed to the outside opposite two ends, the first gap, the second gap and the third gap of having respectively between the side wall of copper block and the hole wall of inner slot hole, intermediate slot hole and outer slot hole, and the width of second gap is less than the width of first gap and second gap, when the prepreg corresponding softening flow and fill up the first gap, the second gap and the third gap in the press bonding process press bonding core plate and light board, the hole wall of inner slot hole and outer slot hole still respectively forms the positioning boss with protruding, this embodiment can promote the combination intensity of copper block and light board and core plate.

Description

Technical Field

[0001] This utility model relates to the field of PCB technology, and in particular to a PCB with pre-embedded copper blocks. Background Technology

[0002] A large number of electronic components are assembled on a PCB (Printed Circuit Board). During the operation of a PCB, the electronic components generate a lot of heat, which needs to be dissipated in a timely manner to ensure that the PCB can work properly and extend its lifespan.

[0003] Currently, one type of PCB has a copper block pre-embedded inside, which simultaneously separates the circuit and the thermal layer, preventing heat from interfering with circuit signals. However, the inventors found in practice that this type of PCB with pre-embedded copper blocks directly inserts and positions the copper block into a pre-set copper embedding slot on the PCB substrate. The adhesion between the copper block and the substrate is poor, and the copper block is prone to falling off during long-term use. Utility Model Content

[0004] The technical problem to be solved by this utility model embodiment is to provide a PCB with pre-embedded copper blocks, which can improve the bonding strength between the copper blocks and the board body.

[0005] To solve the above-mentioned technical problems, the present invention provides the following technical solution: a PCB with pre-embedded copper blocks, comprising:

[0006] A light plate with pre-set internal slots;

[0007] Core plates are respectively stacked on the outer sides of opposite sides of the light plate, and the core plates have pre-set outer slots corresponding to the inner slots;

[0008] A prepreg is disposed between the light plate and the core plates on both sides of the light plate to bond the light plate and the corresponding core plates during the pressing process. The prepreg has a pre-set intermediate slot that connects the inner slot and the outer slot.

[0009] A copper block assembled inside the inner slot and exposed at its opposite ends, passing through the middle slot and the outer slot respectively.

[0010] The sidewall of the copper block has a first gap, a second gap, and a third gap between it and the walls of the inner slot, the middle slot, and the outer slot, respectively. The width of the second gap is smaller than the width of the first gap and the second gap. When the core board and the light board are pressed together by a pressing process, the prepreg softens and flows accordingly to fill the first gap, the second gap, and the third gap. The walls of both the inner slot and the outer slot are also raised to form positioning bosses for abutting and positioning against the sidewall of the copper block.

[0011] Furthermore, the copper block is assembled into the inner slot of the light plate to form a pre-assembled module, and the core board is bonded to the opposite sides of the pre-assembled module by means of the prepreg.

[0012] Furthermore, before bonding the pre-assembled module, pads are formed on the opposite end faces of the copper block through a dry film process and an etching process.

[0013] Furthermore, the outer end face of the pad is machined with screw holes.

[0014] Furthermore, the widths of the first gap and the third gap are 0.1±0.02mm, and the width of the second gap is 0.05±0.02mm.

[0015] Furthermore, each corner of the prepreg and the core board is provided with positioning holes for inserting positioning pins to perform positioning when the inner slot, the middle slot and the outer slot are formed respectively, so as to ensure that the inner slot, the middle slot and the outer slot on the light plate, the prepreg and the core board can be aligned with each other during assembly.

[0016] Furthermore, the positioning holes are formed by drilling after the light plate, the prepreg, and the core plate are sequentially aligned and stacked.

[0017] Furthermore, the positioning holes scattered in each corner are arranged asymmetrically in space, or at least one positioning hole in one corner is a foolproof hole with a hole type incompatible with the positioning holes in other corners.

[0018] After adopting the above technical solution, the present utility model embodiment has at least the following beneficial effects: The present utility model embodiment, through reasonable design of the dimensions of the inner slot, the middle slot and the outer slot, forms a first gap, a second gap and a third gap between the hole walls of the three and the side wall of the copper block, respectively. Positioning bosses are set on the hole walls of the inner slot and the outer slot to abut against the side wall of the copper block for positioning. Moreover, when the core board is bonded to the outer side of the light board by a prepreg and then pressed by a pressing process, the prepreg softens and flows under high temperature and high pressure to fill the first gap, the second gap and the third gap, thereby effectively bonding the copper block with the light board, the prepreg and the core board. Moreover, the width of the second gap is smaller than the width of the first gap and the second gap, so that the prepreg is closer to the copper block in the initial state. This is beneficial for the prepreg to flow better to the first gap and the third gap on both sides when softening and flowing, avoiding hollowness and improving the bonding strength between the copper block and the light board and the core board. Attached Figure Description

[0019] Figure 1This is a cross-sectional schematic diagram of an optional embodiment of the PCB with pre-embedded copper blocks according to the present invention before the copper blocks are installed.

[0020] Figure 2 This is a schematic cross-sectional view of an optional embodiment of the PCB with pre-embedded copper blocks according to the present invention after the copper blocks have been installed.

[0021] Figure 3 This is a cross-sectional schematic diagram of an optional embodiment of the PCB with embedded copper blocks of the present invention, showing the core board bonded to the opposite sides of the pre-assembled module by means of the prepreg.

[0022] Figure 4 This is a schematic cross-sectional view of an optional embodiment of the PCB with embedded copper blocks according to this utility model after lamination.

[0023] Figure 5 This is a schematic diagram of an optional embodiment of the PCB with pre-embedded copper blocks according to the present invention. Detailed Implementation

[0024] The present application will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be understood that the following illustrative embodiments and descriptions are only used to explain the present utility model and are not intended to limit the present utility model. Moreover, the embodiments and features in the embodiments of the present application can be combined with each other unless otherwise specified.

[0025] like Figures 1-4 As shown, an optional embodiment of this utility model provides a PCB with a pre-embedded copper block, comprising:

[0026] A light plate 1 with a pre-set inner groove hole 10;

[0027] Core plates 3 are respectively stacked on the outer sides of opposite sides of the light plate 1, and the core plates 3 have pre-set outer slots 30 corresponding to the inner slots 10.

[0028] A prepreg (commonly abbreviated as PP) 5 is disposed between the smooth plate 1 and the core plates 3 on both sides of the smooth plate 1, so as to correspondingly bond the smooth plate 1 and the corresponding core plates 3 during the pressing process. The prepreg 5 has a pre-set intermediate slot 50 corresponding to and connecting the inner slot 10 and the outer slot 30; and

[0029] A copper block 7 is assembled in the inner slot 10 and is exposed by passing through the middle slot 50 and the outer slot 30 at opposite ends respectively.

[0030] The sidewall of the copper block 7 has a first gap 101, a second gap 501, and a third gap 301 between it and the walls of the inner slot 10, the middle slot 50, and the outer slot 30, respectively. The width of the second gap 301 is smaller than the width of the first gap 101 and the second gap 301. When the core plate 3 and the light plate 1 are pressed together by a pressing process, the prepreg 5 softens and flows accordingly to fill the first gap 101, the second gap 501, and the third gap 301. The walls of the inner slot 10 and the outer slot 30 are also respectively raised to form positioning bosses 103 for abutting and positioning against the sidewall of the copper block 7.

[0031] This embodiment of the invention achieves a first gap, a second gap, and a third gap between the inner slot, the middle slot, and the outer slot and the side wall of the copper block, respectively, through a reasonable design of their dimensions. Positioning bosses are provided on the walls of the inner and outer slots to abut against the side wall of the copper block for positioning. Furthermore, when the core board is bonded to the outer side of the polished board using a pressing process after the prepreg is bonded, the prepreg softens and flows under high temperature and pressure, filling the first gap, the second gap, and the third gap. This effectively bonds the copper block to the polished board, the prepreg, and the core board. Moreover, the width of the second gap is smaller than the widths of the first and second gaps, ensuring that the prepreg is closer to the copper block in the initial state. This facilitates better flow of the prepreg to the first and third gaps on both sides during softening and flow, preventing hollow areas and improving the bonding strength between the copper block and the polished board and the core board.

[0032] In one optional embodiment of this utility model, such as Figures 1-3 As shown, the copper block 7 is assembled into the inner slot 10 of the smooth plate 1 to form a pre-assembled module, and the core plate 3 is bonded to the opposite sides of the pre-assembled module by means of the prepreg 5. In this embodiment, the copper block 7 is first assembled into the inner slot 10 of the smooth plate 1 for preliminary positioning and to form a pre-assembled module, and then the core plate 3 is bonded to the opposite sides of the pre-assembled module by means of the prepreg 5, which facilitates the assembly of the copper block 7.

[0033] In an optional embodiment of this invention, the pre-mounted module forms pads on the opposite end faces of the copper block 7 through a dry film process and an etching process before bonding the prepreg 5. In this embodiment, the pre-mounted module also forms pads before bonding the prepreg 5, thereby forming an internal circuit layer.

[0034] In one optional embodiment of this invention, the outer end face of the pad is machined with screw holes. In this embodiment, by machining screw holes on the outer end face of the pad, the pad can be electrically connected to external circuitry via these screw holes.

[0035] In an optional embodiment of this utility model, the widths of the first gap 101 and the third gap 301 are 0.1±0.02mm, and the width of the second gap 501 is 0.05±0.02mm. In this embodiment, the first gap 101, the third gap 301, and the second gap 501 are designed using the above parameters during specific design and manufacturing. Specific experimental measurements show that the copper block 7 has a strong bonding strength with the light plate 1 and the core plate 3.

[0036] In one optional embodiment of this utility model, such as Figure 5 As shown, each corner of the light plate 1, the prepreg 5, and the core plate 3 is provided with positioning holes 12 for inserting positioning pins to perform positioning when the inner slot 10, the middle slot 50, and the outer slot 30 are respectively formed, so as to ensure that the inner slot 10, the middle slot 50, and the outer slot 30 on the light plate 1, the prepreg 5, and the core plate 3 can be aligned with each other during assembly. In this embodiment, when machining the inner slot 10, the middle slot 50, and the outer slot 30 on the bare plate 1, the prepreg 5, and the core plate 3, the bare plate 1, the prepreg 5, and the core plate 3 are first stacked together. Then, positioning holes 12 are drilled at each corner, and positioning pins are inserted into the positioning holes 12. Next, the inner slot 10, the middle slot 50, and the outer slot 30 are machined on the bare plate 1, the prepreg 5, and the core plate 3 respectively. Finally, when assembling the bare plate 1, the prepreg 5, and the core plate 3, the positioning holes 12 can be aligned and the positioning pins can be inserted to ensure that the inner slot 10, the middle slot 50, and the outer slot 30 are aligned with each other.

[0037] In an optional embodiment of this utility model, the positioning hole 12 is formed by drilling after the light plate 1, the prepreg 5, and the core board 3 are sequentially aligned and stacked. In this embodiment, by drilling after sequentially aligning and stacking the light plate 1, the prepreg 5, and the core board 3, it is ensured that the processed positioning hole 12 can accurately align the inner slot hole 10, the middle slot hole 50, and the outer slot hole 30.

[0038] In one optional embodiment of this utility model, the positioning holes 12 distributed at each corner are asymmetrically arranged in space, or at least one corner positioning hole 12 has a hole type incompatible with the positioning holes 12 in other corners to prevent misalignment. In this embodiment, during the lamination process before pressing, if one of the layers is not oriented correctly, at least one set of positioning holes 12 cannot be aligned, or at least one set of positioning holes 12 cannot be correctly inserted into the positioning pin, thus failing to achieve effective positioning and preventing the mixing of different structural layers.

[0039] The embodiments of the present invention have been described above with reference to the accompanying drawings. However, the present invention is not limited to the specific embodiments described above. The specific embodiments described above are merely illustrative and not restrictive. Those skilled in the art can make many other forms under the guidance of the present invention without departing from the spirit and scope of the claims. All of these forms are within the scope of protection of the present invention.

Claims

1. A PCB with pre-embedded copper blocks, comprising: A light plate with pre-set internal slots; Core plates are respectively stacked on the outer sides of opposite sides of the light plate, and the core plates have pre-set outer slots corresponding to the inner slots; A prepreg is disposed between the light plate and the core plates on both sides of the light plate to bond the light plate and the corresponding core plates during the pressing process. The prepreg has a pre-set intermediate slot that connects the inner slot and the outer slot. A copper block assembled inside the inner slot and exposed at its opposite ends, passing sequentially through the middle slot and the outer slot, respectively. The copper block is characterized in that the sidewall of the copper block has a first gap, a second gap, and a third gap between it and the walls of the inner slot, the middle slot, and the outer slot, respectively, and the width of the second gap is smaller than the width of the first gap and the second gap. When the core board and the light board are pressed together by a pressing process, the prepreg softens and flows accordingly to fill the first gap, the second gap, and the third gap. The walls of both the inner slot and the outer slot are also respectively raised to form positioning bosses for abutting and positioning against the sidewall of the copper block.

2. The PCB with pre-embedded copper blocks as described in claim 1, characterized in that, The copper block is assembled into the inner slot of the light plate to form a pre-assembled module, and the core board is bonded to the opposite sides of the pre-assembled module by means of the prepreg.

3. The PCB with pre-embedded copper blocks as described in claim 2, characterized in that, Before bonding the pre-assembled module, solder pads are formed on the opposite end faces of the copper block through a dry film process and an etching process.

4. The PCB with pre-embedded copper blocks as described in claim 3, characterized in that, The outer end face of the pad is machined with screw holes.

5. The PCB with pre-embedded copper blocks as described in claim 1, characterized in that, The widths of the first gap and the third gap are 0.1±0.02mm, and the width of the second gap is 0.05±0.02mm.

6. The PCB with pre-embedded copper blocks as described in claim 1, characterized in that, The light plate, the prepreg, and the core plate are provided with positioning holes at each corner for inserting positioning pins to perform positioning when the inner slot, the middle slot, and the outer slot are formed respectively, so as to ensure that the inner slot, the middle slot, and the outer slot on the light plate, the prepreg, and the core plate can be aligned with each other during assembly.

7. The PCB with pre-embedded copper blocks as described in claim 6, characterized in that, The positioning holes are formed by drilling after the light plate, the prepreg and the core plate are sequentially aligned and stacked.

8. The PCB with pre-embedded copper blocks as described in claim 6 or 7, characterized in that, The positioning holes scattered in each corner are arranged asymmetrically in space, or at least one positioning hole in one corner is a foolproof hole with a hole type that is incompatible with the positioning holes in other corners.

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