Pad structure of flexible circuit board

Abstract

The invention relates to a pad structure of a flexible circuit board, which comprises a pad and a first bonding wire arranged along the length direction of the flexible circuit board, one end of the first bonding wire is connected with an external power supply, the other end of the first bonding wire extends to one side of the pad in the width direction, the first bonding wire is connected with the side edge of the pad in the width direction, and the other end of the first bonding wire extends to the other side of the pad in the width direction. The connection position of the bonding pad and the bonding wire is transferred to one side of the width direction of the bonding pad, and meanwhile, the bonding pad is provided with a component, so that the bonding pad and the flexible circuit board in the width direction of the bonding pad are not easy to bend, and the reliability of the flexible circuit board is improved. The problem that the connection position of the bonding pad and the bonding wire is prone to fatigue fracture due to the fact that the flexible circuit board is frequently bent along the bending line in the vertical length direction is solved, and the service life of the bonding pad structure of the flexible circuit board is prolonged.

Description

Technical Field

[0001] The present invention relates to the technical field of flexible circuit boards, and in particular to a pad structure of a flexible circuit board. Background Art

[0002] Flexible printed circuit board (Flexible Printed Circuit Board) is referred to as "soft board", commonly known as FPC in the industry. It is a printed circuit board made of flexible insulating substrate (mainly polyimide or polyester film). It can be bent, rolled and folded freely. It has the advantages of small size, light weight, good heat dissipation and solderability, easy installation and connection, and low comprehensive cost. Compared with hard boards, it has certain market advantages. It is suitable for the development of electronic products towards high density, miniaturization and high reliability.

[0003] Taking the light strip FPC as an example, it at least includes a substrate and a soldering pad and a soldering wire laid on the substrate along the length direction of the substrate. One end of the soldering wire is connected to the soldering pad, and the other end is used to connect to an external power supply. The light strip FPC often has a large aspect ratio, that is, the length is much larger than the width. Therefore, it is easy to bend along the length direction during use, that is, it bends along the bending line perpendicular to the length direction. At the same time, due to the difference in hardness between the soldering pad and the soldering wire, stress concentration is easy to occur. Therefore, in the later use of the light strip FPC, fatigue fracture is easy to occur at the connection position of the soldering pad and the soldering wire, resulting in a significant reduction in the life of the light strip FPC.

[0004] Therefore, there is an urgent need for a pad structure of a flexible circuit board with a longer service life. Summary of the invention

[0005] In order to solve the above problems, the present invention provides a pad structure of a flexible circuit board. By setting the connection point between the first welding wire and the pad on the side in the width direction of the pad, the problem of frequent stress on the connection position of the pad and the welding wire during subsequent use is avoided, thereby extending the service life of the flexible circuit board.

[0006] To achieve the above object, the present invention provides the following solutions:

[0007] A pad structure of a flexible circuit board comprises: a pad and a first welding wire arranged along the length direction of the flexible circuit board, one end of the first welding wire is connected to an external power supply, the other end of the first welding wire extends to one side of the pad in the width direction, and the first welding wire is connected to the side edge of the pad in the width direction.

[0008] Preferably, it further comprises a second welding wire, wherein the arrangement direction of the second welding wire is parallel to that of the first welding wire, and the second welding wire is connected to the side edge of the pad in the length direction.

[0009] Preferably, a reinforcement portion for increasing a connection area is provided at a connection point between the second bonding wire and the bonding pad.

[0010] Preferably, the reinforcement portion is arranged in an arc shape.

[0011] Preferably, the first welding wire and the second welding wire are arranged at intervals.

[0012] Preferably, the connection position between the second welding wire and the welding pad constitutes an easy-bending area, the edge of the coating window of the flexible circuit board is located in the easy-bending area, and the edge of the coating window is bent.

[0013] Preferably, the edge of the coated window is wavy.

[0014] Preferably, the first welding wire is connected to the welding pad through a plurality of connecting parts, the connecting parts are arranged along the width direction of the flexible circuit board, and the plurality of connecting parts are arranged at intervals.

[0015] Preferably, a plurality of the first welding wires are provided, and the plurality of the first welding wires are arranged at intervals along the width direction of the flexible circuit board.

[0016] Preferably, it also includes a power distribution welding wire, the first welding wire and the second welding wire are both connected to the power distribution welding wire, one end of the power distribution welding wire away from the welding pad is connected to an external power supply, and the width of the power distribution welding wire gradually decreases in the direction away from the welding pad.

[0017] Compared with the prior art, the present invention has achieved the following technical effects:

[0018] In the pad structure of the flexible circuit board disclosed in the present application, the first welding wire extends to one side of the width direction of the pad and is connected to the side edge of the width direction of the pad, thereby realizing the transfer of the connection position between the pad and the welding wire to one side of the width direction of the pad. At the same time, components are installed on the pad at this time, so that the pad and the flexible circuit board in the width direction of the pad are not easy to bend, thereby avoiding the problem of fatigue fracture of the connection position between the pad and the welding wire due to frequent bending of the flexible circuit board along the bending line in the vertical length direction, thereby improving the service life of the pad structure of the flexible circuit board. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0020] Attached Figure 1 A schematic diagram of an embodiment of the present invention;

[0021] Attached Figure 2 for Figure 1 A magnified schematic diagram of position A;

[0022] Attached Figure 3 is a schematic diagram of another embodiment of the present invention;

[0023] Among them, 1. welding pad; 2. first welding wire; 3. second welding wire; 4. reinforcement part; 5. lamination window; 6. power distribution welding wire; 7. connection part. DETAILED DESCRIPTION

[0024] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0025] The purpose of the present invention is to provide a pad structure for a flexible circuit board, which transfers the connection position between the pad and the welding wire to one side in the width direction of the pad, thereby avoiding the problem that the connection position between the pad and the welding wire is frequently subjected to force during subsequent use.

[0026] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0027] refer to Figure 1-3The pad structure of the flexible circuit board disclosed in the embodiment of the present invention comprises: a pad 1 and a first welding wire 2, wherein the first welding wire 2 is arranged on the substrate of the flexible circuit board along the length direction of the flexible circuit board, one end of the first welding wire 2 is connected to the external power supply, the other end of the first welding wire 2 extends to one side of the width direction of the pad 1, and the first welding wire 2 is connected to the side edge of the width direction of the pad 1; the above method is used to realize the transfer of the connection position between the pad 1 and the welding wire to one side of the width direction of the pad 1. Due to the large length-width ratio of the flexible circuit board, the flexible circuit board is not easy to bend with the bending line extending along the length direction of the flexible circuit board as the bending center during use. At the same time, the back During the use period, components are installed on the pad 1. The installation of the components makes it difficult for the pad 1 and the flexible circuit board in the wide direction of the pad 1 to bend with the bending line perpendicular to the length direction of the flexible circuit board as the bending center. Therefore, transferring the connection position of the pad 1 and the welding wire to one side in the wide direction of the pad 1 can effectively avoid frequent bending of the connection position, thereby avoiding the problem that the connection position of the pad 1 and the welding wire is frequently subjected to stress due to the frequent bending of the flexible circuit board along the bending line perpendicular to the length direction during use, that is, avoiding the problem that the connection position of the pad 1 and the welding wire is prone to fatigue fracture due to stress concentration, thereby improving the service life of the pad structure of the flexible circuit board.

[0028] It should be noted that the width direction mentioned in the present invention refers to the direction perpendicular to the length direction of the flexible circuit board when the pad 1 is laid along the length direction of the flexible circuit board.

[0029] Those skilled in the art can understand that the pad 1 includes a positive electrode pad and a negative electrode pad.

[0030] As a preferred embodiment, it also includes a second welding wire 3, the second welding wire 3 is parallel to the layout direction of the first welding wire 2, the second welding wire 3 is connected to the side of the length direction of the pad 1, and the end of the second welding wire 3 away from the pad 1 is connected to the external power supply. The setting of the second welding wire 3 increases the overall strength of the flexible circuit board along the length direction, thereby improving the bending resistance of the first welding wire 2, making the first welding wire 2 less likely to break; further, in order to improve the connection strength between the second welding wire 3 and the pad 1, the width of the second welding wire 3 in the present application is much greater than the width of the first welding wire 2.

[0031] As a preferred embodiment, in order to further improve the connection strength between the second bonding wire 3 and the bonding pad 1 , a reinforcing portion 4 for increasing the connection area is provided at the connection between the second bonding wire 3 and the bonding pad 1 .

[0032] As a preferred embodiment, the reinforcing portion 4 is arranged in an arc shape. The reinforcing portion 4 arranged in an arc shape can avoid the problem of stress concentration at the connection position.

[0033] As a preferred embodiment, the first welding wire 2 and the second welding wire 3 are arranged at intervals.

[0034] As a preferred embodiment, the connection position between the second welding wire 3 and the welding pad 1 constitutes an easy-to-bend area, and the edge of the coating window 5 of the flexible circuit board is located in the easy-to-bend area. The edge of the coating window 5 is bent, and the bent edge of the coating window 5 can provide bending resistance for the second welding wire 3 in the easy-to-bend area, making the second welding wire 3 less likely to break.

[0035] More preferably, the edge of the portion of the film-coated window 5 outside the easy-bending area is also configured to be bent.

[0036] As a preferred embodiment, the edge of the coated window 5 is wavy.

[0037] Furthermore, the first welding wire 2 is connected to the welding pad 1 through multiple connecting parts 7, and the connecting parts 7 are arranged along the width direction of the flexible circuit board. The multiple connecting parts 7 are arranged at intervals. By providing multiple connecting parts 7, the connection strength between the first welding wire 2 and the welding pad 1 can be effectively improved.

[0038] More preferably, a reinforcing portion for increasing the connection area between the connecting portion 7 and the pad 1 is provided at the connection position between the connecting portion 7 and the pad 1 .

[0039] Furthermore, the plurality of connection portions 7 can be connected to each other along the length direction of the flexible circuit board.

[0040] As a preferred manner, multiple first welding wires 2 are provided, and the multiple first welding wires 2 are arranged at intervals along the width direction of the flexible circuit board. The multiple first welding wires 2 are arranged in parallel to increase the fault tolerance of the flexible circuit board during use. Even if one first welding wire 2 is broken due to force, the other first welding wires 2 still remain connected to the pad 1.

[0041] It can be understood that: the plurality of first bonding wires 2 are all connected to the bonding pad 1 through the connecting portion 7 , and the plurality of first bonding wires 2 can be arranged on the same side of the bonding pad 1 or on different sides of the bonding pad 1 .

[0042] As a preferred embodiment, it also includes a distribution welding wire 6, the first welding wire 2 and the second welding wire 3 are both connected to the distribution welding wire 6, the end of the distribution welding wire 6 away from the welding pad 1 is connected to an external power supply, and the width of the distribution welding wire 6 gradually decreases in the direction away from the welding pad 1, which can effectively prevent breakage caused by bending.

[0043] Adaptive changes made according to actual needs are all within the protection scope of the present invention.

[0044] It should be noted that it is obvious to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the present invention can be implemented in other specific forms without departing from the spirit or essential features of the present invention. Therefore, the embodiments should be regarded as exemplary and non-restrictive from any point of view, and the scope of the present invention is defined by the appended claims rather than the above description, and it is intended that all changes falling within the meaning and scope of the equivalent elements of the claims are included in the invention. Any reference numeral in a claim should not be regarded as limiting the claim to which it relates.

Claims

1. A pad structure of a flexible circuit board, characterized in that: The invention comprises a soldering pad (1) and a first soldering wire (2) arranged along the length direction of the flexible circuit board, wherein one end of the first soldering wire (2) is connected to an external power source, and the other end of the first soldering wire (2) extends to one side of the soldering pad (1) in the width direction, and the first soldering wire (2) is connected to the side edge of the soldering pad (1) in the width direction.

2. The pad structure of the flexible circuit board according to claim 1, characterized in that: It also comprises a second welding wire (3), wherein the second welding wire (3) is arranged in parallel with the first welding wire (2), and the second welding wire (3) is connected to the side edge of the welding pad (1) in the length direction.

3. The pad structure of the flexible circuit board according to claim 2, characterized in that: A reinforcing portion (4) for increasing the connection area is provided at the connection point between the second welding wire (3) and the welding pad (1).

4. The pad structure of the flexible circuit board according to claim 3, characterized in that: The reinforcement portion (4) is arranged in an arc shape.

5. The pad structure of the flexible printed circuit board according to claim 2, characterized in that: The first welding line (2) and the second welding line (3) are arranged at intervals.

6. The pad structure of the flexible printed circuit board according to claim 2, characterized in that: The connection position between the second welding wire (3) and the welding pad (1) forms an easy-bending area, the edge of the film-coated window (5) of the flexible circuit board is located in the easy-bending area, and the edge of the film-coated window (5) is bent.

7. The pad structure of the flexible printed circuit board according to claim 6, characterized in that: The edge of the film-coated window (5) is wavy.

8. The pad structure of the flexible printed circuit board according to claim 1, characterized in that: The first welding wire (2) is connected to the welding pad (1) via a plurality of connecting parts, the connecting parts are arranged along the width direction of the flexible circuit board, and the plurality of connecting parts are arranged at intervals.

9. The pad structure of the flexible printed circuit board according to claim 1, characterized in that: A plurality of the first welding wires (2) are provided, and the plurality of the first welding wires (2) are arranged at intervals along the width direction of the flexible circuit board.

10. The pad structure of the flexible printed circuit board according to claim 1, characterized in that: It also comprises a power distribution welding wire (6), the first welding wire (2) and the second welding wire (3) are both connected to the power distribution welding wire (6), one end of the power distribution welding wire (6) away from the welding pad (1) is connected to an external power supply, and the width of the power distribution welding wire (6) gradually decreases in a direction away from the welding pad (1).

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