Backlight module FPC assembly capable of being directly pressure-welded

Abstract

The utility model discloses a backlight module FPC assembly capable of direct pressure welding, which comprises an FPC circuit body, a flexible connecting body and a bonding pad, the bonding pad comprises a first PI layer, the lower surface of the first PI layer is provided with a first wiring layer, the lower surface of the first wiring layer is provided with a second PI layer, and the lower surface of the second PI layer is provided with a second wiring layer. A first wiring layer is arranged on the upper surface of the first PI layer, a second wiring layer is arranged on the lower surface of the second PI layer, a copper laying layer is arranged on the lower surface of the second wiring layer, a plurality of via holes are formed between the first wiring layer and the second wiring layer and penetrate through the second PI layer, and a plurality of through holes for soldering tin to penetrate through are formed between the second wiring layer and the copper laying layer. Due to the fact that the front face of the backlight module FPC assembly is not provided with wiring and copper laying, soldering tin is not needed after pressure welding, a piece of protective paper does not need to be attached for protection, material cost is saved, and reliability of connection between the backlight module FPC and the LCD main screen FPC is improved.

Description

Technical Field

[0001] The utility model relates to a backlight module, more specifically, to a backlight module FPC component which can be directly pressure-welded. Background Art

[0002] LCD display modules cannot emit light by themselves and need to be assembled with a backlight before they can display. Existing modules all have backlight pads reserved on the LCD main screen FPC. After assembling the backlight, the pads on the backlight module FPC and the LCD main screen FPC are manually aligned, and then soldered with tin wire, and then a piece of protective paper is pasted to protect the soldering position. This requires two manual operation positions, and it is necessary to add yellow protective paper. As shown in Figures 5 and 6, the backlight module FPC is routed on the front side. When the routing is about to reach the PIN position, the via 210 passes through the back side of the FPC, and the routing on both sides is done at the same time and copper is laid to form a copper-paved area 50. Perforations are made in the copper-paved area 50 to facilitate the solder to pass through and connect to the main screen FPC pad. Since copper is laid on the front side, yellow protective paper needs to be attached.

[0003] Chinese utility model patent document CN210630007U discloses a backlight module welding positioning fixture, which includes a vertical plate, a horizontal plate extending horizontally from the top of the vertical plate, and a pressing device hinged on the horizontal plate; wherein the vertical plate is used to place the backlight module vertically; the horizontal plate is used to place the flexible circuit board horizontally; the pressing device is used to press the bent backlight module FPC pin on the flexible circuit board pad for welding. The pressing device includes a swing arm and a pressure rod; one end of the swing arm is hinged to the middle of the horizontal plate, and the other end of the swing arm extends toward the vertical plate and fixes the pressure rod horizontally; the pressure rod is arranged horizontally, and can swing up and down under the linkage of the swing arm, and can press the bent backlight module FPC pin on the flexible circuit board pad. A pair of magnets are respectively embedded on the surfaces of the swing arm opposite to the horizontal plate. A push rod is fixed on the swing arm, and the push rod is bent from the swing arm and extends downward to the side of the vertical plate. The push rod is crimped onto the upper surface of the swing arm by a screw, and the screw is threadedly connected to the swing arm and passes through the swing arm; the horizontal plate is provided with an escape hole for evading the screw. The bottom edge of the vertical plate is provided with a retaining edge for preventing the backlight module from falling, and a clip is fixed on the side of the vertical plate, and the clip can clamp the backlight module on the vertical plate. A refuge window is provided on at least one side of the vertical plate for facilitating the grabbing of the backlight module. A top plate is embedded in the vertical plate, and the top plate is flush with the outer surface of the vertical plate and can be adjusted up and down to support the lower surface of the FPC pin of the backlight module. A card slot is provided at the top of the top plate, and the card slot is used to place the FPC pin of the backlight module.

[0004] Obviously, the patent uses a clamp to press the backlight module FPC pins and the flexible circuit board pads together to facilitate welding. This structure cannot solve the problem that the existing FPC pads need to be attached with yellow protective paper. Utility Model Content

[0005] Based on this, it is necessary to provide a backlight module FPC component that can be directly press-welded to address the above technical problems. The backlight module FPC component that can be directly press-welded includes an FPC circuit body, a flexible connection body and a soldering pad. The soldering pad includes a first PI layer, a first routing layer is provided on the lower surface of the first PI layer, a second PI layer is provided on the lower surface of the first routing layer, a second routing layer is provided on the lower surface of the second PI layer, a copper layer is provided on the lower surface of the second routing layer, a number of vias are provided between the first routing layer and the second routing layer, the vias penetrate the second PI layer, and a number of through holes for solder to pass through are provided between the second routing layer and the copper layer. When performing SMT on components, tin is applied to the backlight pad of the LCD main screen FPC, and the tinning height is 60-120um. After assembling the backlight module FPC assembly of the utility model, the backlight module FPC assembly of the utility model is aligned with the backlight pad of the LCD main screen FPC, and temperature and pressure are applied by machine pressure welding technology to melt the tin of the pad on the LCD main screen FPC, and pressure weld it together with the copper-plated area, i.e., the copper-plated layer, on the back of the backlight module FPC assembly of the utility model. Since there is no routing and copper-plating on the front of the backlight module FPC assembly of the utility model, there is no solder after pressure welding, and there is no need to attach a protective paper for protection, which saves material costs and improves the reliability of the connection between the backlight module FPC and the LCD main screen FPC.

[0006] In order to solve the above technical problems, the utility model adopts the following technical solutions:

[0007] A backlight module FPC component capable of direct pressure welding, characterized in that the backlight module FPC component capable of direct pressure welding comprises an FPC circuit body, a flexible connection body and a welding pad,

[0008] The pad comprises a first PI layer, a first routing layer is arranged on the lower surface of the first PI layer, a second PI layer is arranged on the lower surface of the first routing layer, a second routing layer is arranged on the lower surface of the second PI layer, and a copper layer is arranged on the lower surface of the second routing layer.

[0009] A plurality of vias are arranged between the first wiring layer and the second wiring layer, and the vias penetrate the second PI layer. A plurality of through holes for solder to pass through are arranged between the second wiring layer and the copper-plated layer.

[0010] As a preferred implementation of the backlight module FPC assembly capable of direct pressure welding provided by the utility model, the diameter of the via hole is 0.1 mm to 0.25 mm.

[0011] As a preferred implementation of the backlight module FPC assembly capable of direct pressure welding provided by the utility model, the diameter of the via hole is 0.2 mm.

[0012] As a preferred implementation of the backlight module FPC assembly capable of direct pressure welding provided by the utility model, the diameter of the perforation is 0.2 mm to 0.4 mm.

[0013] As a preferred implementation of the backlight module FPC assembly capable of direct pressure welding provided by the utility model, the diameter of the perforation is 0.3 mm.

[0014] As a preferred implementation of the backlight module FPC assembly capable of direct pressure welding provided by the utility model, a plurality of first etching grooves arranged in parallel are provided on the lower surface of the second wiring layer.

[0015] As a preferred implementation of the backlight module FPC assembly capable of direct pressure welding provided by the utility model, the depth of the first etching groove is 50 microns to 100 microns.

[0016] As a preferred implementation of the backlight module FPC assembly capable of direct pressure welding provided by the utility model, the depth of the first etching groove is 70 microns.

[0017] As a preferred embodiment of the backlight module FPC assembly capable of direct pressure welding provided by the utility model, a plurality of evenly distributed second etching grooves are provided on the inner wall of the through hole.

[0018] As a preferred implementation of the backlight module FPC assembly capable of direct pressure welding provided by the utility model, the depth of the second etching groove is 40 microns to 70 microns.

[0019] Compared with the prior art, the utility model has the following beneficial effects:

[0020] The utility model provides a backlight module FPC component that can be directly press-welded. When SMT is performed on components, tin is applied to the backlight pad of the LCD main screen FPC, and the tinning height is 60-120um. After assembling the backlight module FPC component of the utility model, the backlight module FPC component of the utility model is aligned with the backlight pad of the LCD main screen FPC, and temperature and pressure are applied by machine press-welding technology to melt the tin of the pad on the LCD main screen FPC, and press-weld it together with the copper-plated area, i.e., the copper-plated layer, on the back of the backlight module FPC component of the utility model. Since there is no routing and copper-plating on the front of the backlight module FPC component of the utility model, there is no solder after press-welding, and it is not necessary to attach a protective paper for protection, which saves material costs and improves the reliability of the connection between the backlight module FPC and the LCD main screen FPC.

[0021] In addition, a plurality of parallel first etching grooves may be provided on the lower surface of the second wiring layer. The depth of the first etching grooves is 50 microns to 100 microns. Preferably, the depth of the first etching grooves is 70 microns. By utilizing the first etching grooves on the lower surface of the second wiring layer, when copper plating is performed, the connection adhesion between the copper plating layer and the second wiring layer can be effectively enhanced, thereby improving the reliability of the electrical connection between the second wiring layer and the copper plating layer.

[0022] In addition, a plurality of evenly distributed second etching grooves may be provided on the inner wall of the perforation. The depth of the second etching grooves is 40 microns to 70 microns. Preferably, the depth of the second etching grooves is 50 microns. The second etching grooves on the inner wall of the perforation can effectively enhance the connection adhesion between the copper layer and the inner wall of the perforation, thereby further improving the reliability of the electrical connection between the second routing layer and the copper layer. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the scheme in the utility model, a brief introduction is given below to the drawings required for use in the description of the embodiments. Obviously, the drawings described below are some embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0024] FIG1 is a schematic structural diagram of a backlight module FPC assembly that can be directly pressure-welded according to the present invention;

[0025] FIG2 is a schematic structural diagram of the FPC assembly of the backlight module that can be directly pressure-welded in FIG1 , from another viewing angle;

[0026] Figure 3 It is a partial structural schematic diagram of another embodiment of the backlight module FPC assembly capable of direct pressure welding of the utility model;

[0027] Figure 4 Figure 3A detailed enlarged schematic diagram of area A of a partial structural schematic diagram of a backlight module FPC component that can be directly pressed and welded;

[0028] FIG5 is a schematic structural diagram of an existing backlight module FPC assembly;

[0029] FIG6 is a schematic structural diagram of the FPC assembly of the backlight module in FIG5 , from another viewing angle;

[0030] The markings in the figure are as follows: 1, first PI layer; 2, first routing layer; 21, via; 3, second PI layer; 4, second routing layer; 41, first etching groove; 5, copper plating layer; 51, perforation; 511, second etching groove; S1, FPC circuit body; S2, connection body; S3, pad. DETAILED DESCRIPTION

[0031] In order to enable those skilled in the art to better understand the solution of the utility model, the technical solution in the embodiment of the utility model will be clearly and completely described below in conjunction with the drawings in the embodiment of the utility model. Obviously, the described embodiment is only a part of the embodiment of the utility model, not all of the embodiments. Based on the embodiment of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the utility model.

[0032] As described in the background technology, in the prior art, for LCD display modules, CD display modules cannot emit light by themselves and need to be assembled with backlights to display. The existing modules all reserve backlight pads on the LCD main screen FPC. After assembling the backlight, the pads on the backlight module FPC and the LCD main screen FPC are manually aligned, and then soldered with tin wire, and then a piece of protective paper is attached to protect the soldering position. This requires two manual operation positions, and it is necessary to add yellow protective paper.

[0033] In order to solve this technical problem, the utility model provides a backlight module FPC component S that can be directly pressed and welded, comprising an FPC circuit body S1, a flexible connection body S2 and a pad S3. The pad S3 comprises a first PI layer 1, a first wiring layer 2 is provided on the lower surface of the first PI layer 1, a second PI layer 3 is provided on the lower surface of the first wiring layer 2, a second wiring layer 4 is provided on the lower surface of the second PI layer 3, and a copper layer 5 is provided on the lower surface of the second wiring layer 4. In addition, a plurality of vias 21 are provided between the first wiring layer 2 and the second wiring layer 4, the vias 21 penetrate the second PI layer 3, and a plurality of through holes 51 for solder to pass through are provided between the second wiring layer 4 and the copper layer 5.

[0034] Through the above structural design, when the components are SMT-ed, tin is applied to the backlight pad of the LCD main screen FPC, and the tinning height is 60-120um. After the backlight module FPC assembly of the utility model is assembled, the backlight module FPC assembly of the utility model is aligned with the backlight pad of the LCD main screen FPC, and the machine pressure welding technology is used to apply temperature and pressure to melt the tin of the pad on the LCD main screen FPC, and pressure weld it together with the copper-plated area on the back of the backlight module FPC assembly of the utility model, that is, the copper-plated layer 5. Since there is no routing and copper-plating on the front of the backlight module FPC assembly of the utility model, there is no solder after pressure welding, and there is no need to attach a protective paper for protection, which saves material costs and improves the reliability of the connection between the backlight module FPC and the LCD main screen FPC.

[0035] In order to enable those skilled in the art to better understand the present invention, the technical solutions in the embodiments of the present invention will be described in detail below in conjunction with the accompanying drawings, so that the advantages and features of the present invention can be more easily understood by those skilled in the art, thereby making a clearer and more definite definition of the protection scope of the present invention.

[0036] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features and technical solutions in the embodiments may be combined with each other.

[0037] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.

[0038] Example 1

[0039] As shown in FIG. 1 and FIG. 2 , the backlight module FPC assembly capable of direct pressure welding comprises an FPC circuit body S1 , a flexible connection body S2 and a welding pad S3 .

[0040] The pad S3 includes a first PI layer 1, a first routing layer 2 is provided on the lower surface of the first PI layer 1, a second PI layer 3 is provided on the lower surface of the first routing layer 2, a second routing layer 4 is provided on the lower surface of the second PI layer 3, and a copper layer 5 is provided on the lower surface of the second routing layer 4.

[0041] In addition, a plurality of via holes 21 are provided between the first wiring layer 2 and the second wiring layer 4 , and the via holes 21 penetrate the second PI layer 3 . A plurality of through holes 51 for solder to pass through are provided between the second wiring layer 4 and the copper plating layer 5 .

[0042] It should be noted that the diameter of the via hole 21 is 0.1 mm to 0.25 mm. Preferably, the diameter of the via hole 21 is 0.2 mm.

[0043] In addition, the diameter of the through hole 51 is 0.2 mm to 0.4 mm. Preferably, the diameter of the through hole 51 is 0.3 mm.

[0044] The working mode of this embodiment is described below.

[0045] When performing SMT on components, tin is applied to the backlight pad of the LCD main screen FPC, and the tinning height is 60-120um. After assembling the backlight module FPC assembly of the utility model, the backlight module FPC assembly of the utility model is aligned with the backlight pad of the LCD main screen FPC, and temperature and pressure are applied by machine pressure welding technology to melt the tin of the pad on the LCD main screen FPC, and pressure welding is performed with the copper-plated area on the back of the backlight module FPC assembly of the utility model, that is, the copper-plated layer 5. Since there is no routing and copper-plating on the front of the backlight module FPC assembly of the utility model, there is no solder after pressure welding, and there is no need to attach a protective paper for protection, which saves material costs and improves the reliability of the connection between the backlight module FPC and the LCD main screen FPC.

[0046] Example 2

[0047] The backlight module FPC assembly capable of direct pressure welding provided in Example 1 is further optimized. Specifically, a plurality of first etching grooves 41 arranged in parallel are provided on the lower surface of the second wiring layer 4 .

[0048] It should be noted that the depth of the first etching groove 41 is 50 micrometers to 100 micrometers.

[0049] In addition, the depth of the first etching groove 41 is 70 micrometers.

[0050] The working mode of this embodiment is described below.

[0051] By utilizing the first etching groove 41 on the lower surface of the second wiring layer 4, the connection adhesion between the copper plating layer 5 and the second wiring layer 4 can be effectively enhanced during copper plating, thereby improving the reliability of the electrical connection between the second wiring layer 4 and the copper plating layer 5.

[0052] Example 3

[0053] The backlight module FPC assembly capable of direct pressure welding provided in Embodiment 1 or 2 is further optimized. Specifically, a plurality of evenly distributed second etching grooves 511 are provided on the inner wall of the through hole 51 .

[0054] It should be noted that the depth of the second etching groove 511 is 40 micrometers to 70 micrometers. Preferably, the depth of the second etching groove 511 is 50 micrometers.

[0055] The working mode of this embodiment is described below.

[0056] The second etching groove 511 on the inner wall of the through hole 51 can effectively enhance the connection adhesion between the copper layer 5 and the inner wall of the through hole 51 , thereby further improving the reliability of the electrical connection between the second wiring layer 4 and the copper layer 5 .

[0057] The terms "coupling" and "coupling" involved in the embodiments of the present application should be understood in a broad sense. For example, they may refer to a direct physical connection, or an indirect connection achieved through electronic devices, such as a connection achieved through resistors, inductors, capacitors or other electronic devices.

[0058] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral one; it can be a mechanical connection, an electrical connection, or communication with each other; it can be a direct connection, or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0059] Obviously, the embodiments described above are only some embodiments of the present application, rather than all embodiments. The preferred embodiments of the present application are given in the accompanying drawings, but they do not limit the patent scope of the present application. The present application can be implemented in many different forms. On the contrary, the purpose of providing these embodiments is to make the understanding of the disclosure of the present application more thorough and comprehensive. Although the present application is described in detail with reference to the aforementioned embodiments, for those skilled in the art, it is still possible to modify the technical solutions recorded in the aforementioned specific implementation methods, or to replace some of the technical features therein with equivalents. Any equivalent structure made using the contents of the specification and drawings of this application, directly or indirectly used in other related technical fields, is similarly within the scope of patent protection of this application.

Claims

1. A backlight module FPC component capable of direct pressure welding, characterized in that: The backlight module FPC component (S) capable of direct pressure welding comprises an FPC circuit body (S1), a flexible connection body (S2) and a solder pad (S3), wherein the solder pad (S3) comprises a first PI layer (1), a first wiring layer (2) is provided on the lower surface of the first PI layer (1), a second PI layer (3) is provided on the lower surface of the first wiring layer (2), a second wiring layer (4) is provided on the lower surface of the second PI layer (3), a copper-plated layer (5) is provided on the lower surface of the second wiring layer (4), a plurality of vias (21) are provided between the first wiring layer (2) and the second wiring layer (4), the vias (21) penetrate the second PI layer (3), and a plurality of through holes (51) for solder to pass through are provided between the second wiring layer (4) and the copper-plated layer (5).

2. The backlight module FPC assembly capable of direct pressure welding according to claim 1, characterized in that: The diameter of the via hole (21) is 0.1 mm to 0.25 mm.

3. The backlight module FPC assembly capable of direct pressure welding according to claim 2, characterized in that: The diameter of the through hole (21) is 0.2 mm.

4. The backlight module FPC assembly capable of direct pressure welding according to claim 1, characterized in that: The diameter of the perforation (51) is 0.2 mm to 0.4 mm.

5. The backlight module FPC assembly capable of direct pressure welding according to claim 4, characterized in that: The diameter of the perforation (51) is 0.3 mm.

6. The backlight module FPC assembly capable of direct pressure welding according to claim 1, characterized in that: A plurality of first etching grooves (41) arranged in parallel are provided on the lower surface of the second wiring layer (4).

7. The backlight module FPC assembly capable of direct pressure welding according to claim 6, characterized in that: The depth of the first etching groove (41) is 50 micrometers to 100 micrometers.

8. The backlight module FPC assembly capable of direct pressure welding according to claim 7, characterized in that: The depth of the first etching groove (41) is 70 micrometers.

9. The backlight module FPC assembly capable of direct pressure welding according to claim 1, characterized in that: A plurality of evenly distributed second etching grooves (511) are provided on the inner wall of the through hole (51).

10. The backlight module FPC assembly capable of direct pressure welding according to claim 9, characterized in that: The depth of the second etching groove (511) is 40 micrometers to 70 micrometers.

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