CN207219151U - Flexible printed circuit board and electronic device - Google Patents

Abstract

The utility model provides a kind of flexible printed circuit board, including at least one electric connecting terminal, the electric connecting terminal includes substrate and fits in multiple reinforcing blocks of the substrate side, the substrate is provided with multiple vias, each reinforcing block covers corresponding via, spacer region is formed between multiple reinforcing blocks, the first area of the substrate is right against the reinforcing block, the second area of the substrate is right against the spacer region, the rigidity of the stiffening plate is more than the rigidity of the substrate, so that the rigidity at the second area is less than the rigidity at the first area.The utility model additionally provides a kind of electronic installation.The utility model improves the bending property of the electric connecting terminal of flexible circuit board.

Description

Flexible printed circuit board and electronic device

technical field

The utility model relates to a flexible printed circuit board, in particular to a flexible printed circuit board and an electronic device with the flexible printed circuit board.

Background technique

A flexible printed circuit board (Flexible Printed Circuit, FPC) can be applied to various flexible occasions. Among them, FPC with double-sided wiring can have higher wiring density, so that it can meet the conductive requirements of complex circuits, and is more and more favored by the industry. The FPC with double-sided wiring usually arranges lines on both sides of the insulating layer, then opens a via hole on the insulating layer, and fills the via hole with metal to electrically connect the lines on both sides. However, after repeated bending of the FPC, the metal in the via hole may be separated from the inner wall of the via hole, thereby causing the lines on both sides of the FPC to fail to conduct, which affects the performance of the FPC.

Utility model content

The utility model provides a flexible printed circuit board and an electronic device with the flexible printed circuit board, which improves the performance of the flexible printed circuit board with double-sided wiring.

The utility model provides a flexible printed circuit board, which includes at least one electrical connection end, the electrical connection end includes a base and a plurality of reinforcing blocks attached to one side of the base, and the base is provided with a plurality of holes, each of the reinforcement blocks covers the corresponding via hole, a spacer is formed between a plurality of the reinforcement blocks, the first area of the base is facing the reinforcement block, and the second area of the base is opposite to the reinforcement block. A region is directly opposite to the spacer region, and the stiffness of the reinforcing plate is greater than that of the base, so that the stiffness at the second region is smaller than the stiffness at the first region.

Wherein, the base includes a first conductive layer, an insulating layer and a second conductive layer stacked in sequence, and the first conductive layer is arranged on a side close to the reinforcing block, and the plurality of via holes are arranged on At a position on the insulating layer corresponding to the first region, the first conductive layer is electrically connected to the second conductive layer through the plurality of via holes.

Wherein, the first conductive layer includes first conductive strips arranged side by side, and the first conductive strips are arranged in the first region, and the second conductive layer includes second conductive strips arranged side by side, and the second conductive strips are arranged side by side. The conductive strip is electrically connected to the first conductive strip through the plurality of via holes.

Wherein, at least two via holes connected in parallel are provided between the first conductive strip and the second conductive strip.

Wherein, the second region is located between two parallel via holes.

Wherein, the plurality of via holes include a first via hole and a second via hole, and the first via hole and the second via hole are respectively located on two adjacent first conductive strips, along the In the extending direction of the first conductive strip, the first via hole is offset relative to the second via hole.

Wherein, the first conductive layer further includes third conductive strips arranged side by side, and the third conductive strips are arranged in the second region.

Wherein, a conductive medium is also included, and the conductive medium is filled in the via hole and adhered to the hole wall of the via hole.

Wherein, the conductive medium is silver paste or carbon paste.

The utility model also provides an electronic device, comprising the flexible printed circuit board described in any one of the above-mentioned embodiments.

A flexible printed circuit board provided by the utility model divides the base of the electrical connection end into a first area and a second area, wherein a plurality of reinforcing blocks are arranged on the first area, and the gap between the second area and the reinforcing block Since the stiffness of the reinforcing block is greater than that of the base, the stiffness of the second region that is not opposite to the reinforcing block is smaller than that of the first region, and the second region is under the action of an external force. Bending in the direction a can drive the two adjacent reinforcing blocks to move closer to the interval area, thereby realizing the bending of the electrical connection end in the direction a; the second area bends in the direction b under the action of an external force, which can drive the adjacent The two reinforcing blocks are both far away from the spacing area, so that the electrical connection end is bent in the direction b, thereby improving the bending performance of the electrical connection end.

Description of drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. Obviously, the accompanying drawings in the following description are only some embodiments of the present invention. For those skilled in the art, other drawings can also be obtained based on these drawings without creative effort.

Fig. 1 is a schematic structural diagram of a flexible printed circuit board provided by the first embodiment of the present invention.

Fig. 2 is a schematic structural view of the flexible printed circuit board provided by the first embodiment of the present invention in a bent state.

Fig. 3 is a schematic structural view of the flexible printed circuit board provided by the first embodiment of the present invention in another bending state.

Fig. 4 is a schematic cross-sectional structure view along AA' of Fig. 1 .

Fig. 5 is a partial top view of the flexible printed circuit board provided by the first embodiment of the present invention.

Fig. 6 is a partial top view of the flexible printed circuit board provided by the second embodiment of the present invention.

Fig. 7 is a schematic cross-sectional structure view along BB' of Fig. 6 .

Fig. 8 is a partial top view of the flexible printed circuit board provided by the third embodiment of the present invention.

Detailed ways

The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. example. Based on the embodiments of the present utility model, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts belong to the scope of protection of the present utility model.

In the description of the embodiments of the present utility model, it should be understood that the orientation or positional relationship indicated by the terms "above", "upper side", "below" and "lower side" are based on the orientation or positional relationship shown in the accompanying drawings , is only for the convenience of describing the utility model and simplifying the description, but does not imply or indicate that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the utility model.

Referring to FIG. 1 , the present invention provides a flexible printed circuit board 100 , which includes at least one electrical connection end 110 and a middle section 120 connected to the electrical connection end 110 . The middle section 120 has an electronic circuit to realize electrical conduction between the electrical connection ends 110 .

Please refer to FIG. 1 to FIG. 3 , a flexible printed circuit board 100 provided by the first embodiment of the present invention. The electrical connection terminal 110 includes a base 111 and a plurality of reinforcing blocks 112 attached to one side of the base 111 . A spacer 113 is formed between the reinforcing blocks 112 . The first area 114 of the base 111 is facing the reinforcing block 112 , and the second area 115 of the base 111 is facing the spacer 113 . The stiffness of the reinforcing block 112 is greater than that of the base 111 , so that the stiffness at the second region 115 is smaller than the stiffness at the first region 114 .

Referring to FIGS. 1-3 , in this embodiment, the base 111 of the electrical connection terminal 110 is divided into a first area 114 and a second area 115, wherein a plurality of reinforcing blocks 112 are arranged on the first area 114, and the second The area 115 is opposite to the interval 113 between the reinforcing blocks 112. Since the stiffness of the reinforcing blocks 112 is greater than that of the base 111, the stiffness of the second area 115 that is not opposite to the reinforcing blocks 112 is smaller than that of the first The rigidity of the region 114, the second region 115 bends toward the direction a under the action of an external force, and can drive the two adjacent reinforcing blocks 112 to move closer to the spacer 113, thereby realizing the bending of the electrical connection end 110 toward the direction a ; The second area 115 bends toward the direction b under the action of an external force, which can drive the two adjacent reinforcing blocks 112 away from the spacer 113, so that the electrical connection end 110 bends toward the direction b, thereby improving the electrical connection. The bending performance of the connecting end 110 . That is, the strength of the part of the flexible printed circuit board 100 can be increased through the reinforcing block 112 provided separately, and the influence on the overall bending performance can be reduced. Certainly, each reinforcing block 112 may be a whole piece of reinforcing structure connected as a whole, and in this case, the reinforcing structure also covers the second region 115 .

Please refer to FIG. 4 , the base 111 includes a first conductive layer 116 , an insulating layer 117 and a second conductive layer 118 stacked in sequence, and the first conductive layer 116 is disposed on a side close to the reinforcing block 112 . The insulating layer 117 includes a plurality of via holes 119 penetrating through the insulating layer 117 . A plurality of via holes 119 are located in the first region 114 , and the first conductive layer 116 is electrically connected to the second conductive layer 118 through the plurality of via holes 119 . That is to say, each of the reinforcing blocks 112 is facing at least one plurality of via holes 119 to increase the electrical connection between the plurality of via holes 119 and the first conductive layer 116 and the second conductive layer 118 reliability.

The electrical connection terminal 110 further includes a conductive medium 121 , the conductive medium 121 is filled in the plurality of via holes 119 and attached to the walls of the plurality of via holes 119 . The conductive medium 121 can be silver paste or carbon paste. By using silver paste or carbon paste, the elongation/stretch performance of the conductive medium 121 can be increased, so that it can remain attached to the inner wall of the via hole 119 when the substrate 111 is bent, and is not prone to detachment.

In this embodiment, the projection area of the reinforcing block 112 on the second conductive layer 118 covers the projection area of the plurality of via holes 119 on the second conductive layer 118, so that the via holes 119 cannot be bent. The bending or bending performance is reduced, thereby preventing the separation between the conductive medium 121 in the via hole 119 and the inner wall of the via hole 119 , resulting in an open circuit at the via hole 119 of the flexible printed circuit board 100 .

The present application does not specifically limit the area of the projected area of the reinforcing block 112 on the second conductive layer 118 . Preferably, under the condition that the reinforcing block 112 covers a plurality of via holes 119, the area of the reinforcing block 112 can be as small as possible, so that the area where the electrical connection end 110 of the flexible printed circuit board 100 cannot be bent As small as possible, so as to improve the bending performance of the electrical connection end 110 of the flexible printed circuit board 100 .

In a possible implementation manner, please refer to FIG. 4 and FIG. 5 , the first conductive layer 116 includes first conductive strips 122 arranged side by side. The second conductive layer 118 includes a plurality of second conductive strips 123 . The first conductive strip 122 is disposed opposite to the second conductive strip 123 . A plurality of via holes 119 are connected between the first conductive strips 122 and the second conductive strips 123 . The reinforcing block 112 is disposed opposite to the first conductive strip 122 , and is disposed right to the plurality of via holes 119 on the first conductive strip 122 . The first conductive layer 116 further includes third conductive strips 124 arranged side by side. The third conductive strips 124 are arranged between the first conductive strips 122 and are consistent with the extending direction of the first conductive strips 122 . The third conductive strip 124 is disposed on the second region 115 , and there is no via hole 119 between the third conductive strip 124 and the second conductive layer 118 . In this embodiment, the projection area of the spacer region 113 on the second conductive layer 118 covers the projection area of the third conductive strip 124 on the second conductive layer 118 . That is to say, the reinforcement block 112 covers the area with the via hole 119 on the first conductive layer 116, but does not cover the area without the via hole 119 on the first conductive layer 116, so that the area with high rigidity can be made as large as possible. small, thereby improving the bending performance of the electrical connection end 110 of the flexible printed circuit board 100 .

For a possible implementation, please refer to FIG. 6 and FIG. 7 . FIG. 6 is a flexible printed circuit board 100 provided by the second embodiment of the present invention. Fig. 7 is a sectional view along BB' in Fig. 6 . Different from the first embodiment, at least two via holes 119 a and 119 b connected in parallel are provided between the first conductive strip 122 and the second conductive strip 123 . That is to say, the wiring path between the first conductive strip 122 and the second conductive strip 123 adopts a redundant design, so as to ensure that there are at least two As long as any one of the paths is connected, the first conductive strip 122 and the second conductive strip 123 will be electrically connected, thereby improving the reliability of the double-layer flexible printed circuit board 100 .

In a possible implementation manner, the reinforcing block 112 is also provided at the parallel via holes 119a and 119b, and the second region 115 is located between any two parallel via holes 119a and 119b, so as to increase the flexibility of printing. The local bending/stretching performance of the electrical connection end 110 of the circuit board 100 .

For a possible implementation, please refer to FIG. 8 . FIG. 8 is a flexible printed circuit board 100 provided by the third embodiment of the present invention. Different from the first embodiment, the plurality of via holes 119 includes a first via hole 119c and a second via hole 119d. The first via hole 119c and the second via hole 119d are respectively located on two adjacent first conductive strips 122 . The first via hole 119 c has an offset distance L relative to the second via hole 119 d along the extending direction of the first conductive strip 122 . The offset distance L is greater than or equal to (R1+R2)/2, the R1 is the diameter of the first via hole 119c, and the R2 is the diameter of the second via hole 119d. The first via hole 119c and the second via hole 119d face the two reinforcement blocks 112 respectively, and a spacer 113 is provided between the two reinforcement blocks 112 , that is, the two reinforcement blocks 112 can move closer or farther away from each other. Compared with the reinforcing block 112 in which the first via hole 119c and the second via hole 119d are aligned, the staggered manner of the reinforcing block 112 in this embodiment can further improve the reliability of the electrical connection end 110 of the flexible printed circuit board 100 . bending performance.

Optionally, the insulating layer 117 is made of insulating resin material, such as polyimide or polyester.

Optionally, the material of the reinforcing block 112 may be stainless steel, aluminum foil, polyester, polyimide, glass fiber, polytetrafluoroethylene or polycarbonate and the like.

The present invention also provides an electronic device, comprising the flexible printed circuit board 100 described in any one of the above-mentioned embodiments. The flexible printed circuit board 100 can be applied to a flexible touch screen, and electronic devices can use the flexible touch screen to manufacture smart phones, notebook computers, and the like. In addition, electronic devices can also be organic photovoltaic batteries, organic sensors, wearable electronics, flexible memory, healthcare, smart items, smart textiles, etc.

The above is a preferred embodiment of the present utility model, it should be pointed out that for those of ordinary skill in the art, without departing from the principle of the present utility model, some improvements and modifications can also be made, these improvements and modifications It is also regarded as the protection scope of the present utility model.

Claims (10)

1. A flexible printed circuit board, characterized in that it includes at least one electrical connection end, the electrical connection end includes a base and a plurality of reinforcing blocks attached to one side of the base, and the base is provided with a plurality of Each of the reinforcement blocks covers the corresponding via hole, a spacer is formed between a plurality of the reinforcement blocks, the first area of the base is facing the reinforcement block, and the second area of the base is Directly with respect to the spacer region, the stiffness of the reinforcing plate is greater than the stiffness of the base such that the stiffness at the second region is less than the stiffness at the first region. 2. The flexible printed circuit board according to claim 1, wherein the base comprises a first conductive layer, an insulating layer and a second conductive layer stacked in sequence, and the first conductive layer is arranged near the One side of the reinforcing block, the plurality of via holes are provided on the insulating layer corresponding to the position of the first region, and the first conductive layer communicates with the second conductive layer through the plurality of via holes. layer electrical connection. 3. The flexible printed circuit board according to claim 2, wherein the first conductive layer includes first conductive strips arranged side by side, the first conductive strips are arranged in the first region, and the first conductive strips are arranged side by side. The second conductive layer includes second conductive strips arranged side by side, and the second conductive strips are electrically connected to the first conductive strips through the plurality of via holes. 4. The flexible printed circuit board according to claim 3, wherein at least two via holes connected in parallel are provided between the first conductive strip and the second conductive strip. 5. The flexible printed circuit board according to claim 4, wherein the second region is located between two parallel via holes. 6. The flexible printed circuit board according to claim 3, wherein the plurality of via holes comprise a first via hole and a second via hole, and the first via hole and the second via hole are respectively located at On two adjacent first conductive strips, the first via hole is offset relative to the second via hole along the extending direction of the first conductive strip. 7. The flexible printed circuit board according to claim 3, wherein the first conductive layer further comprises third conductive strips arranged side by side, and the third conductive strips are arranged in the second region. 8 . The flexible printed circuit board according to claim 1 , further comprising a conductive medium, the conductive medium is filled in the via hole and adhered to the wall of the via hole. 9. The flexible printed circuit board according to claim 8, wherein the conductive medium is silver paste or carbon paste. 10. An electronic device, comprising the flexible printed circuit board according to any one of claims 1-9.