An outer core plate, a circuit board, and an electronic device

Abstract

This utility model relates to the field of electronic product technology, and discloses an outer core board, a circuit board, and an electronic device. The outer core board includes a stacked substrate and copper foil. The outer core board has riveting holes and an annular stress buffer zone surrounding the riveting holes. Multiple stress buffer holes are located within the annular stress buffer zone and are evenly spaced circumferentially. When the outer core board is used in riveting operations, the riveting holes are subjected to the tensile force of the rivets. At this time, the multiple stress buffer holes in the annular stress buffer zone can release the stress in the riveting holes, thus buffering the tensile force and preventing damage or cracking of the riveting holes, thereby improving the product yield.

Description

Technical Field

[0001] This utility model relates to the field of electronic product technology, and in particular to an outer core board, circuit board and electronic device. Background Technology

[0002] As electronic devices evolve towards miniaturization and high performance, PCB (Printed Circuit Board) design is gradually moving towards high frequency, high speed, high-density interconnection, and ultra-thin design. PCBs are constructed by stacking and riveting multiple layers of core boards. During the lamination process, because there is no core board on the outer side of the outer core board, the outer core board is easily affected by the tensile force of the rivets, leading to damage or cracking at the riveting holes. This, in turn, results in poor sliding properties of the core board after lamination, severely affecting product yield.

[0003] Therefore, there is an urgent need for an outer core board, circuit board, and electronic device to solve the aforementioned problems. Utility Model Content

[0004] Based on the above, the purpose of this utility model is to provide an outer core board, circuit board, and electronic device. The multiple stress buffer holes of the annular stress buffer can release the stress of the riveting holes, buffer the tensile force, prevent the riveting holes from being damaged or cracked, and improve the product yield.

[0005] To achieve the above objectives, the present invention adopts the following technical solution:

[0006] In a first aspect, an outer core board is provided, the outer core board comprising a stacked substrate and a copper foil, the outer core board being provided with riveting holes, the outer core board being provided with an annular stress buffer zone surrounding the riveting holes, the copper foil being provided with a plurality of stress buffer holes, the plurality of stress buffer holes being located in the annular stress buffer zone and being evenly spaced along the circumference.

[0007] As a preferred technical solution for an outer core board, the stress buffer hole is arc-shaped, and the center of the stress buffer hole is located on the center line of the riveting hole.

[0008] As a preferred technical solution for an outer core board, the stress buffer holes are four in number.

[0009] As a preferred technical solution for an outer core board, the spacing A between adjacent stress buffer holes is the same as the diameter D of the riveting hole.

[0010] As a preferred technical solution for an outer core board, the ratio of the distance B between the stress buffer hole and the center line of the riveting hole to the diameter D of the riveting hole is in the range of 1.5-2.

[0011] As a preferred technical solution for an outer core board, the width C of the stress buffer hole along the radial direction of the riveting hole ranges from 1mm to 2mm.

[0012] As a preferred technical solution for an outer core board, the thickness of the outer core board is no greater than 4 mil.

[0013] As a preferred technical solution for an outer core board, the copper foil is provided with multiple sets of detection holes, which are symmetrically arranged with respect to the center line of the riveting hole, and the sets of detection holes are located between the riveting hole and the annular stress buffer zone.

[0014] In a second aspect, a circuit board is provided, comprising a plurality of inner core boards and two or more outer core boards as described in any one of the embodiments, wherein the two outer core boards are respectively located on both sides of the plurality of inner core boards.

[0015] Thirdly, an electronic device is provided, including the aforementioned circuit board.

[0016] The beneficial effects of this utility model are as follows:

[0017] This invention provides an outer core board, a circuit board, and an electronic device. The outer core board has riveting holes and an annular stress buffer zone surrounding the riveting holes. The annular stress buffer zone has multiple stress buffer holes evenly spaced circumferentially. When the outer core board is used in riveting operations, the riveting holes are subjected to the tensile force of the rivets. At this time, the multiple stress buffer holes in the annular stress buffer zone can release the stress in the riveting holes, buffering the tensile force and preventing damage or cracking of the riveting holes, thus improving the product yield. Attached Figure Description

[0018] To more clearly illustrate the technical solutions in the embodiments of this utility model, the drawings used in the description of the embodiments of this utility model will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on the content of the embodiments of this utility model and these drawings without creative effort.

[0019] Figure 1 This is a structural schematic diagram of the riveting area of ​​the outer core plate provided in a specific embodiment of this utility model.

[0020] The markings in the image are as follows:

[0021] 1. Outer core board; 11. Riveting holes; 12. Annular stress buffer zone; 13. Stress buffer holes; 14. Inspection hole group; 15. Connecting ribs. Detailed Implementation

[0022] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present invention and not intended to limit it. Furthermore, it should be noted that, for ease of description, the accompanying drawings show only the parts relevant to the present invention, not the entire structure.

[0023] In the description of this utility model, unless otherwise explicitly specified and limited, the terms "connected," "linked," and "fixed" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0024] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0025] In the description of this embodiment, the terms "upper," "lower," "left," and "right," etc., refer to the orientation or positional relationship shown in the accompanying drawings. They are used only for ease of description and simplification of operation, 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. Therefore, they should not be construed as limitations on this utility model. In addition, the terms "first" and "second" are only used for distinction in description and have no special meaning.

[0026] As electronic devices evolve towards miniaturization and high performance, PCB (Printed Circuit Board) design is gradually moving towards high frequency, high speed, high-density interconnection, and ultra-thin design. PCBs are constructed by stacking and riveting multiple layers of core boards. During the lamination process, because there is no core board on the outer side of the outer core board, the outer core board is easily affected by the tensile force of the rivets, leading to damage or cracking at the riveting holes. This, in turn, results in poor sliding properties of the core board after lamination, severely affecting product yield.

[0027] To solve the above problems, such as Figure 1As shown, this embodiment provides an outer core board 1, which includes a stacked substrate and a copper foil. The outer core board 1 is provided with riveting holes 11 and an annular stress buffer zone 12, which is arranged around the riveting holes 11. Multiple stress buffer holes 13 are provided on the copper foil, located within the annular stress buffer zone 12 and evenly spaced circumferentially. When the outer core board 1 is used in riveting operations, the riveting holes 11 are subjected to the tensile force of the rivet. At this time, the multiple stress buffer holes 13 of the annular stress buffer zone 12 can release the stress in the riveting holes 11, thus buffering the tensile force. The riveting holes 11 are less prone to damage or cracking, improving the product yield.

[0028] It should be noted that the stress buffer holes 13 on the copper foil can be removed by etching to expose the substrate.

[0029] Preferably, the stress buffer hole 13 is arc-shaped, with its center located on the center line of the riveting hole 11. The arc-shaped structure can evenly disperse the radial stress generated by the rivet pulling, avoiding core board cracking caused by stress concentration. Compared with straight or zigzag holes, the stress distribution of the arc-shaped structure is more uniform, which can effectively reduce interlayer deformation, improve the stress release effect, and facilitate the processing of the stress buffer hole 13. Furthermore, the arc-shaped structure is arranged concentrically with the riveting hole 11, which can minimize the space occupied by the outer core board 1 and improve the space utilization of the circuit board. In other embodiments, the stress buffer hole 13 can also be rectangular, circular, or elliptical, etc.

[0030] In this embodiment, there are four stress buffer holes 13. In order to ensure the strength of the annular stress buffer 12, the spacing A between adjacent stress buffer holes 13 is the same as the diameter D of the riveting hole 11. That is, a connecting rib 15 is provided between adjacent stress buffer holes 13. The length of the connecting rib 15 is the diameter D of the riveting hole 11. This prevents the outer core board 1 from being broken by the riveting machine when it is thin, which would affect the positioning ability and cause layer misalignment.

[0031] Preferably, the ratio of the distance B between the stress buffer hole 13 and the center line of the riveting hole 11 to the diameter D of the riveting hole 11 is in the range of 1.5-2. In this embodiment, the diameter of the center hole is 1.524 mm, and the distance B between the stress buffer hole 13 and the center line of the riveting hole 11 on the side closer to the riveting hole 11 is 2.5 mm.

[0032] More preferably, the width C of the stress buffer hole 13 along the radial direction of the riveting hole 11 ranges from 1mm to 2mm. Specifically, the width C of the stress buffer hole 13 is 1mm, 1.2mm, 1.4mm, 1.6mm, 1.8mm, or 2mm.

[0033] In this embodiment, the thickness of the outer core board 1 is no more than 4mil, which can solve the problem of core board damage and scrapping caused by rivet pulling with a thickness of no more than 4mil.

[0034] Preferably, the copper foil is provided with multiple detection hole groups 14, which are symmetrically arranged relative to the center line of the riveting hole 11, and the detection hole groups 14 are located between the riveting hole 11 and the annular stress buffer zone 12. The position of the detection hole groups 14 is detected by using a 100x microscope to determine the hole position accuracy of the riveting hole 11. The detection method is existing technology and will not be described in detail here. In this embodiment, each detection hole group 14 includes two straight holes arranged radially spaced along the riveting hole 11. The length of the straight holes can be the same as the diameter D of the riveting hole 11. It should be noted that the straight holes on the copper foil can be removed by etching to expose the substrate.

[0035] This embodiment also provides a circuit board, including multiple inner core boards and two outer core boards 1 as described above, with the two outer core boards 1 located on both sides of the multiple inner core boards. When the inner core boards and outer core boards 1 are riveted together, the two outer core boards 1 will not be damaged or cracked when the rivets are pulled, thus improving the yield rate.

[0036] This embodiment also provides an electronic device, including the circuit board described above, which improves product yield.

[0037] Note that the above description is merely a preferred embodiment of the present invention and the technical principles employed. Those skilled in the art will understand that the present invention is not limited to the specific embodiments described herein, and various obvious changes, readjustments, and substitutions can be made without departing from the scope of protection of the present invention. Therefore, although the present invention has been described in detail through the above embodiments, the present invention is not limited to the above embodiments, and may include many other equivalent embodiments without departing from the concept of the present invention. The scope of the present invention is determined by the scope of the appended claims.

Claims

1. An outer core plate comprising a base material and a copper skin stacked, said outer core plate being provided with a riveting hole (11), characterized in that, The outer core board is provided with an annular stress buffer (12), which is arranged around the riveting hole (11). The copper sheet is provided with a plurality of stress buffer holes (13), which are located in the annular stress buffer (12) and are evenly spaced along the circumference.

2. The outer core panel of claim 1, wherein, The stress buffer hole (13) is arc-shaped, and the center of the stress buffer hole (13) is located on the center line of the riveting hole (11).

3. The outer core panel of claim 2, wherein, There are four stress buffer holes (13).

4. The outer core panel of claim 3, wherein, The spacing A between adjacent stress buffer holes (13) is the same as the diameter D of the riveting hole (11).

5. The outer core panel of claim 2, wherein, The ratio of the distance B between the stress buffer hole (13) and the center line of the riveting hole (11) to the diameter D of the riveting hole (11) is in the range of 1.5-2.

6. The outer core panel of claim 2, wherein, The width C of the stress buffer hole (13) along the radial direction of the riveting hole (11) ranges from 1 mm to 2 mm.

7. The outer core panel according to any one of claims 1-6, characterized in that The thickness of the outer core board is no more than 4 mil.

8. The outer core panel according to any one of claims 1-6, characterized in that The copper sheet is provided with a plurality of detection hole groups (14), which are symmetrically arranged with respect to the center line of the riveting hole (11), and the detection hole groups (14) are located between the riveting hole (11) and the annular stress buffer zone (12).

9. A circuit board, characterized by It includes a plurality of inner core plates and two outer core plates as described in any one of claims 1-8, wherein the two outer core plates are respectively located on both sides of the plurality of inner core plates.

10. An electronic device, comprising: Includes the circuit board as described in claim 9.

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