阅读说明：本技术 一种无线充电接受线圈及其制造方法 (Wireless charging receiving coil and manufacturing method thereof ) 是由 满方明 于 2019-11-05 设计创作，主要内容包括：本发明公开了一种无线充电接受线圈及其制造方法，该制造方法包括以下步骤：制作第一双面FPC线圈；制作第二双面FPC线圈；取一第三胶膜，对其在预设金属导通孔位置处钻孔；将所述第一双面FPC线圈和第二双面FPC线圈放置于所述第三胶膜两侧，并进行层压；在所述第二双面FPC线圈外侧以该侧铜箔制作第四平面螺旋金属线路；在所述第四平面螺旋金属线路外侧快压第二PI保护膜；对所述第二PI保护膜在所述预设金属导通孔位置处开孔；本发明提供了一种制造成本低、支持大功率的FPC线圈结构。(The invention discloses a wireless charging receiving coil and a manufacturing method thereof, wherein the manufacturing method comprises the following steps: manufacturing a first double-sided FPC coil; manufacturing a second double-sided FPC coil; taking a third adhesive film, and drilling holes at the position of the preset metal via hole; placing the first double-sided FPC coil and the second double-sided FPC coil on two sides of the third adhesive film, and laminating; manufacturing a fourth plane spiral metal circuit on the outer side of the second double-sided FPC coil by using the side copper foil; quickly pressing a second PI protective film on the outer side of the fourth planar spiral metal circuit; opening a hole in the position of the preset metal via hole in the second PI protective film; the invention provides an FPC coil structure which is low in manufacturing cost and supports high power.)

1. A method for manufacturing a wireless charging receiving coil is characterized by comprising the following steps:

step S1: manufacturing a first double-sided FPC coil;

the manufacturing method of the first double-sided FPC coil comprises the following steps:

step S1 a: drilling a first adhesive film at the position of the preset metal via hole;

step S1 b: respectively placing copper foils on two sides of the first adhesive film, and laminating;

step S1 c: respectively manufacturing a first planar spiral metal circuit and a second planar spiral metal circuit on two sides of the first adhesive film by using copper foils on the two sides;

step S1 d: quickly pressing a first PI protective film on the outer side of the first planar spiral metal circuit;

step S2: manufacturing a second double-sided FPC coil;

the manufacturing of the second double-sided FPC coil comprises the following steps:

step S2 a: drilling a second adhesive film at the position of the preset metal via hole;

step S2 b: respectively placing copper foils on two sides of the second adhesive film, and laminating;

step S1 c: manufacturing a third planar spiral metal circuit on one side of the second adhesive film by using the copper foil on the side;

step S3: taking a third adhesive film, and drilling holes at the position of the preset metal via hole;

step S4: placing the first double-sided FPC coil and the second double-sided FPC coil on two sides of the third adhesive film, enabling the second planar spiral metal circuit and the third planar spiral metal circuit to contact the third adhesive film, and laminating;

step S5: manufacturing a fourth plane spiral metal circuit on the outer side of the second double-sided FPC coil by using the side copper foil;

step S6: and quickly pressing a second PI protective film on the outer side of the fourth plane spiral metal circuit.

2. The method of manufacturing a wireless charging receiver coil according to claim 1, further comprising the steps of:

step S7: and filling tin alloy into the metal through hole by a HASL process.

3. The method of manufacturing a wireless charging receiver coil according to claim 1, further comprising the steps of:

step S8: and arranging a connecting disc for connecting an external circuit on the first planar spiral metal circuit, and plating a metal protection layer on the connecting disc by an ENIG process.

4. The method of manufacturing a wireless charging receiver coil according to claim 1, further comprising the steps of:

step S9: and punching the shapes of the first plane spiral metal circuit and the fourth plane spiral metal circuit.

5. A wireless charging receiving coil is characterized by comprising a first double-sided FPC coil, a second double-sided FPC coil and a third adhesive film, wherein,

the first double-sided FPC coil comprises a first adhesive film and copper foils laminated on two sides of the first adhesive film, a first planar spiral metal circuit and a second planar spiral metal circuit are respectively manufactured on two sides of the first adhesive film by using the copper foils on the two sides, and a first PI protective film is arranged on the outer side of the first planar spiral metal circuit;

the second double-sided FPC coil comprises a second adhesive film and copper foils laminated on two sides of the second adhesive film, a third planar spiral metal circuit and a fourth planar spiral metal circuit are respectively manufactured on two sides of the second adhesive film by using the copper foils on the two sides, and a second PI protective film is arranged on the outer side of the fourth planar spiral metal circuit;

the first double-sided FPC coil and the second double-sided FPC coil are laminated on two sides of the third adhesive film, and the second planar spiral metal circuit and the third planar spiral metal circuit are in contact with the third adhesive film;

the first plane spiral metal circuit and the fourth plane spiral metal circuit are conducted through a plurality of metal through holes.

6. The wireless charging receiver coil of claim 1, wherein the first planar spiral metal trace and the second planar spiral metal trace are identical.

7. The wireless charging receiver coil of claim 1, wherein the third planar spiral metal trace and the fourth planar spiral metal trace are the same.

8. The wireless charging receiver coil of claim 1, wherein the metallic via is filled with a tin alloy.

9. The wireless charging receiving coil according to claim 1, wherein a land for connecting an external circuit is provided on the first planar spiral metal wire, and the land is plated with a metal protective layer.

Technical Field

The application relates to the field of mobile phone wireless charging coils, in particular to a wireless charging receiving coil and a manufacturing method thereof.

Background

At present, the PI double-sided copper-clad plate FCCL is used as a base material in the manufacture of the FPC mobile phone wireless charging coil, and the FPC process is adopted for production and mainly comprises the following steps: cutting a PI flexible double-sided copper-clad plate, drilling, performing via and whole copper plating, performing D/F and exposure, performing D.E.S, quickly pressing a PI protective film, connecting a disc ENIG, punching the appearance and the like.

However, the current FPC coil is more competitive in cost, and has a tendency of increasing power in transmission power, so a new FPC coil structure with low cost and high power and a manufacturing method thereof are urgently needed to be provided.

Disclosure of Invention

The invention aims to provide a novel FPC coil structure with low cost and high power and a manufacturing method thereof.

In order to solve the above problems, the present invention provides a method for manufacturing a wireless charging receiver coil, comprising the steps of: step S1: manufacturing a first double-sided FPC coil; the manufacturing method of the first double-sided FPC coil comprises the following steps: step S1 a: drilling a first adhesive film at the position of the preset metal via hole; step S1 b: respectively placing copper foils on two sides of the first adhesive film, and laminating; step S1 c: respectively manufacturing a first planar spiral metal circuit and a second planar spiral metal circuit on two sides of the first adhesive film by using copper foils on the two sides; step S1 d: quickly pressing a first PI protective film on the outer side of the first planar spiral metal circuit; step S2: manufacturing a second double-sided FPC coil; the manufacturing of the second double-sided FPC coil comprises the following steps: step S2 a: drilling a second adhesive film at the position of the preset metal via hole; step S2 b: respectively placing copper foils on two sides of the second adhesive film, and laminating; step S1 c: manufacturing a third planar spiral metal circuit on one side of the second adhesive film by using the copper foil on the side; step S3: taking a third adhesive film, and drilling holes at the position of the preset metal via hole; step S4: placing the first double-sided FPC coil and the second double-sided FPC coil on two sides of the third adhesive film, enabling the second planar spiral metal circuit and the third planar spiral metal circuit to contact the third adhesive film, and laminating; step S5: manufacturing a fourth plane spiral metal circuit on the outer side of the second double-sided FPC coil by using the side copper foil; step S6: and quickly pressing a second PI protective film on the outer side of the fourth plane spiral metal circuit.

Preferably, the method further comprises the following steps: step S7: and filling tin alloy into the metal through hole by a HASL process.

Preferably, the method further comprises the following steps: step S8: and arranging a connecting disc for connecting an external circuit on the first planar spiral metal circuit, and plating a metal protection layer on the connecting disc by an ENIG process.

Preferably, the method further comprises the following steps: step S9: and punching the shapes of the first plane spiral metal circuit and the fourth plane spiral metal circuit.

The invention also provides a wireless charging receiving coil, which comprises a first double-sided FPC coil, a second double-sided FPC coil and a third adhesive film, wherein the first double-sided FPC coil comprises a first adhesive film and copper foils laminated on two sides of the first adhesive film, and a first planar spiral metal circuit and a second planar spiral metal circuit are respectively manufactured on two sides of the first adhesive film by the copper foils on the two sides; the second double-sided FPC coil comprises a second adhesive film and copper foils laminated on two sides of the second adhesive film, and a third planar spiral metal circuit and a fourth planar spiral metal circuit are respectively manufactured on two sides of the second adhesive film by using the copper foils on the two sides; the first double-sided FPC coil and the second double-sided FPC coil are laminated on two sides of the third adhesive film, and the second planar spiral metal circuit and the third planar spiral metal circuit are in contact with the third adhesive film; the first plane spiral metal circuit and the fourth plane spiral metal circuit are conducted through a plurality of metal through holes.

Preferably, the first planar spiral metal line and the second planar spiral metal line are the same.

Preferably, the third planar spiral metal line and the fourth planar spiral metal line are the same.

Preferably, the metal via hole is filled with tin alloy.

Preferably, a connecting disc for connecting an external circuit is arranged on the first planar spiral metal circuit, and a metal protective layer is plated on the connecting disc.

Compared with the prior art, the invention has the following technical effects:

1. the manufacturing method of the wireless charging receiving coil is simple in process, and manufacturing cost can be reduced;

2. the wireless charging receiving coil in the embodiment of the invention adopts the high-power FPC type coil formed by overlapping a plurality of layers of plane spiral circuits.

Of course, it is not necessary for any product in which the invention is practiced to achieve all of the above-described advantages at the same time.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings needed to be used in the description of the embodiments will be briefly introduced below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings based on these drawings without creative efforts. In the drawings:

FIG. 1 is a schematic diagram of a planar spiral metal circuit on a first side of a conventional FPC coil;

FIG. 2 is a schematic diagram of a planar spiral metal trace on the second side of a conventional FPC coil;

FIG. 3 is a flowchart illustrating a method for manufacturing a wireless charging receiving coil according to an embodiment of the invention;

fig. 4 is a schematic cross-sectional view of a wireless charging receiver coil according to an embodiment of the invention.

Detailed Description

The wireless charging receiving coil and the manufacturing method thereof provided by the present invention will be described in detail with reference to the accompanying drawings, which are implemented on the premise of the technical solution of the present invention, and a detailed implementation manner and a specific operation process are given, but the protection scope of the present invention is not limited to the following embodiments, and those skilled in the art can modify and color the wireless charging receiving coil without changing the spirit and content of the present invention.

At present, the wireless charging coil of the FPC type mobile phone comprises an FPC coil and a soft magnetic separation sheet, and the structural characteristics of the FPC coil are shown in figures 1-2:

the FPC coil is provided with two planar spiral metal circuits which are respectively attached to two sides of a PI film 1, and the two planar spiral metal circuits are basically the same in size parameters such as inner diameter, outer diameter, turns, line width, line spacing and the like;

each turn of the planar spiral metal circuit 2 on one side of the FPC coil is provided with a disconnection interval, the innermost circle of the metal circuit passes through each turn of the circuit disconnection interval and extends to the outside of the outermost circle of the metal circuit, metal via holes 4 are formed in the vicinity of each turn of the circuit disconnection interval, and the metal via holes 4 pass through the PI film 1 below and are connected with the metal via holes 5 of the planar spiral metal circuit 3 on the other side;

each turn of the planar spiral metal line 3 on the other side of the FPC coil is continuous without a break interval, and the innermost line thereof is connected to the outside of the line by the metal via hole 5 and the lead wire of the innermost line of the planar spiral metal line 2 on the other side of the PI film 1.

The outer sides of the planar spiral metal circuits on the two sides of the PI film 1 of the FPC coil are respectively covered with a PI protective film;

5. and a connecting disc for connecting an external circuit is arranged on the plane spiral metal circuit on one side, and a protective metal layer such as nickel, gold and the like is plated on the connecting disc.

The embodiment of the invention discloses a method for manufacturing a wireless charging receiving coil, and please refer to fig. 3, which comprises the following steps:

step S1: manufacturing a first double-sided FPC coil;

the manufacturing method of the first double-sided FPC coil comprises the following steps:

step S1 a: drilling a first adhesive film at the position of the preset metal via hole;

step S1 b: respectively placing copper foils on two sides of the first adhesive film, and laminating;

step S1 c: respectively manufacturing a first planar spiral metal circuit and a second planar spiral metal circuit on two sides of the first adhesive film by using copper foils on the two sides;

step S1 d: quickly pressing a first PI protective film on the outer side of the first planar spiral metal circuit;

step S2: manufacturing a second double-sided FPC coil;

the manufacturing of the second double-sided FPC coil comprises the following steps:

step S2 a: drilling a second adhesive film at the position of the preset metal via hole;

step S2 b: respectively placing copper foils on two sides of the second adhesive film, and laminating;

step S1 c: manufacturing a third planar spiral metal circuit on one side of the second adhesive film by using the copper foil on the side;

step S3: taking a third adhesive film, and drilling holes at the position of the preset metal via hole;

step S4: placing the first double-sided FPC coil and the second double-sided FPC coil on two sides of the third adhesive film, enabling the second planar spiral metal circuit and the third planar spiral metal circuit to contact the third adhesive film, and laminating;

step S5: manufacturing a fourth plane spiral metal circuit on the outer side of the second double-sided FPC coil by using the side copper foil;

step S6: and quickly pressing a second PI protective film on the outer side of the fourth plane spiral metal circuit.

Step S7: and filling tin alloy into the metal through hole by a HASL process.

Step S8: and arranging a connecting disc for connecting an external circuit on the first planar spiral metal circuit, and plating a metal protection layer on the connecting disc by an ENIG process.

Step S9: and punching the shapes of the first plane spiral metal circuit and the fourth plane spiral metal circuit.

The manufacturing method of the wireless charging receiving coil omits the substrate full-page electroplating thickening process, the metal via hole is simultaneously manufactured in the etching circuit, so that the existing FPC coil drilling process is omitted, the metal via hole adopts the HASL process and the like, and the manufacturing process cost of the FPC coil is reduced.

The wireless charging receiving coil utilizes the HASL process to realize the function of electrically connecting different layers of circuits of the wireless charging receiving coil through the metal via hole, and the HASL process can also be replaced by other processes in combination with the actual conditions of a coil manufacturer, such as: and (3) through the hole, filling the connecting material into the hole, namely, copper paste, needle cylinder tin dispensing, screen printing tin paste and the like, and then realizing the electric conduction function of the connecting material in the conducting hole by thermal solidification or melting.

The embodiment of the invention also discloses a wireless charging receiving coil, please refer to fig. 4, which comprises a first double-sided FPC coil 200, a second double-sided FPC coil 300 and a third adhesive film 100, wherein the first double-sided FPC coil 200 comprises a first adhesive film 210 and copper foils laminated on two sides of the first adhesive film 210, a first planar spiral metal circuit 220 and a second planar spiral metal circuit 230 are respectively manufactured on two sides of the first adhesive film 210 by the copper foils on the side, and a first PI protective film 500 is arranged on the outer side of the first planar spiral metal circuit 220; the second double-sided FPC coil 300 includes a second adhesive film 310 and copper foils laminated on both sides thereof, a third planar spiral metal line 320 and a fourth planar spiral metal line 330 are respectively formed on both sides of the second adhesive film 310 with the copper foils on the sides, and a second PI protective film 600 is disposed on the outer side of the fourth planar spiral metal line 330; the first double-sided FPC coil 200 and the second double-sided FPC coil 300 are laminated on both sides of the third adhesive film 100, and the second planar spiral metal wire 230 and the third planar spiral metal wire 320 contact the third adhesive film 100; the first planar spiral metal line 220 and the fourth planar spiral metal line 330 are connected through a plurality of metal vias 400.

As a preferred embodiment, the first planar spiral metal wire 220 and the second planar spiral metal wire 230 have the same shape, size, material, etc.

As a preferred embodiment, the third planar spiral metal wire 320 and the fourth planar spiral metal wire 330 are identical in shape, size, material, and the like.

As a preferred embodiment, the metal via 400 is filled with tin alloy.

As a preferred embodiment, a land for connecting an external circuit is provided on the first planar spiral metal wire 220, and the land is plated with a metal protection layer.

The first planar spiral metal line 220 and the fourth planar spiral metal line 330 of the first double-sided FPC coil 200 and the second double-sided FPC coil 300 of the embodiment of the present invention maintain the shape and the size of the planar spiral metal line of the existing FPC type coil, but the whole wireless charging receiving coil is different in lamination:

the materials of the first planar spiral metal line 220 and the fourth planar spiral metal line 330 are made of pure copper foil, and the existing FPC coil is made of pure copper foil plus electroplated copper;

the first planar spiral metal circuit 220 of the first double-sided FPC coil 200 and the fourth planar spiral metal circuit 330 of the second double-sided FPC coil 300 are bonded by pure adhesive films or pressure-sensitive adhesive films, and the FPC coils are bonded by adhesive films containing PI films;

the metal via holes 400 of the first and second double-sided FPC coils 200 and 300 are made of tin alloy, while the conventional FPC coil via holes are made of copper plating.

The disclosure above is only one specific embodiment of the present application, but the present application is not limited thereto, and any variations that can be made by those skilled in the art are intended to fall within the scope of the present application.