CN111883352A

CN111883352A - Shielding sheet for wireless charging module and wireless charging module

Info

Publication number: CN111883352A
Application number: CN202010536159.0A
Authority: CN
Inventors: 蔡鹏�; 周苗苗; 王磊
Original assignee: Xinwei Communication Jiangsu Co ltd
Current assignee: Xinwei Communication Jiangsu Co ltd
Priority date: 2020-06-12
Filing date: 2020-06-12
Publication date: 2020-11-03

Abstract

The invention discloses a shielding sheet for a wireless charging module and the wireless charging module, wherein the shielding sheet for the wireless charging module comprises an outer ring magnetic sheet and a center magnetic sheet, a through hole is formed in the outer ring magnetic sheet, the center magnetic sheet is arranged in the through hole, and a gap is formed between the peripheral wall of the center magnetic sheet and the wall surface of the through hole; the outer ring magnetic sheet comprises at least one first magnetic conduction layer, and the first magnetic conduction layer is a nanocrystalline strip, an amorphous strip or a metal soft magnetic strip; the central magnetic sheet comprises at least one second magnetic conduction layer, and the second magnetic conduction layer is a nanocrystalline strip, an amorphous strip or a metal soft magnetic strip. Compared with the traditional magnetic shielding sheet and the traditional charging module, the shielding sheet for the wireless charging module and the wireless charging module provided by the invention have the advantages that the charging efficiency and the saturation current of the wireless charging module are improved under the condition of the same shielding performance; in addition, the traditional 'broken magnetic' process is not needed in the production process of the shielding sheet, so that the manufacturing process of the shielding sheet is reduced, and the manufacturing cost of the shielding sheet is reduced.

Description

Shielding sheet for wireless charging module and wireless charging module

Technical Field

The invention relates to the technical field of electromagnetic shielding structures, in particular to a shielding sheet for a wireless charging module and the wireless charging module.

Background

Wireless charging technology, also called inductive charging or contactless charging, utilizes near-field induction, i.e. inductive coupling, to transfer energy from a power supply device (i.e. a transmitting end) to a power consumer (i.e. a receiving end). The main characteristic of the wireless charging technology is the close-range inductive coupling of the non-contact coupling transformer, which is similar to the conventional resonant switching power supply.

The existing wireless charging product is provided with a magnetic separation sheet, wherein the magnetic separation sheet is a magnetic material and is generally a thin ferrite, an amorphous strip or a nanocrystalline strip. The strip material generally has high magnetic permeability, the thickness range of a single-layer magnetic strip material is 10-30 um, and the strip material is generally in a multilayer structure in a laminating and overlapping mode, so that the overall inductance of the material is improved. The magnetic separation sheet can provide a low-impedance path for magnetic lines of force, isolate magnetic energy emitted outwards, and prevent a magnetic field from penetrating through a magnetic material to reach the inside of electronic equipment, so that parts such as metal (batteries) in the electronic equipment absorb the magnetic field to generate energy loss, electromagnetic interference is reduced, and the magnetoelectric conversion efficiency is improved. The magnetism gathering effect of the magnetic shielding material can effectively reduce the number of turns of the charging coil, so that the eddy current loss of the coil is reduced. Therefore, a magnetic shielding material having high saturation induction, high magnetic permeability, and low loss is required.

With the rapid development of the electronic information industry, higher and higher requirements are put forward on the wireless charging technology, and the wireless charging technology is high in power and efficiency and becomes a trend of future development. The traditional wireless charging magnetic separation sheet technology is to reduce eddy current loss of the magnetic sheet and fragment the magnetic sheet (namely, a magnetic strip), for example, the invention patent of China with the application number of 201280062847.1 discloses that the magnetic sheet is mechanically crushed into fragmented magnetic conduction sheets. This technique exists the cost of manufacture height, and the piece easily exposes and causes risks such as pollution, and simultaneously, magnetic sheet fragmentation can greatly reduced magnetic sheet magnetic permeability, needs the multilayer stack just can satisfy the required high magnetic conduction passageway of high efficiency charge in order to reduce the magnetic leakage risk. However, with the trend of miniaturization and lightness of mobile terminal products such as smart phones, watches, earphones and the like, a new demand for lightness and thinness of the magnetic separation sheet for wireless charging is provided. Although the traditional structure of fragmentized multi-layer stacking of the magnetic separation sheets can provide a strong magnetic gathering effect, the traditional structure cannot better meet the development requirements of lightness, thinness and low cost due to higher thickness and higher cost. Therefore, the problems of the conventional wireless charging, such as low charging efficiency, high cost, complex process and low yield, are important factors that hinder the development of the wireless charging. How to reduce the thickness of the wireless charging module as much as possible under the condition of ensuring the charging efficiency, and reducing the production cost of the wireless charging module is a problem to be solved urgently in the development of the wireless charging module.

Disclosure of Invention

The technical problem to be solved by the invention is as follows: provided are a low-cost shielding sheet for a wireless charging module with high charging efficiency and a wireless charging module.

In order to solve the technical problems, the invention adopts the technical scheme that: a shielding sheet for a wireless charging module comprises an outer ring magnetic sheet and a center magnetic sheet, wherein the outer ring magnetic sheet is provided with a through hole, the center magnetic sheet is arranged in the through hole, and a gap is formed between the peripheral wall of the center magnetic sheet and the wall surface of the through hole; the outer ring magnetic sheet comprises at least one first magnetic conduction layer, and the first magnetic conduction layer is a nanocrystalline strip, an amorphous strip or a metal soft magnetic strip; the central magnetic sheet comprises at least one second magnetic conduction layer, and the second magnetic conduction layer is a nanocrystalline strip, an amorphous strip or a metal soft magnetic strip.

In order to solve the technical problems, the invention also adopts the following technical scheme: wireless module of charging includes the charging coil, still includes above-mentioned wireless shielding piece for the module that charges, central magnetic sheet corresponds to the hollow region setting of charging coil.

Further, the inner edge face of the charging coil is coplanar with the peripheral wall of the central magnetic sheet.

The invention has the beneficial effects that: because the outer ring magnetic sheet is vertical to the direction of the induced eddy current, when the outer ring magnetic sheet is provided with a plurality of first magnetic conduction layers which are stacked, insulating glue exists between the stacked first magnetic conduction layers, no matter how high the magnetic loss mu of the outer ring magnetic sheet is, the long-free-path eddy current cannot be generated (when the outer ring magnetic sheet is provided with only one first magnetic conduction layer, the thickness of the single-layer first magnetic conduction layer is thinner (the thickness is less than or equal to 30 mu m), and the long-free-path eddy current cannot be generated), so the outer ring magnetic sheet not only maintains the ultrahigh magnetic conductivity, but also has lower eddy current loss; in addition, although the eddy current generated by the magnetic field on the central magnetic sheet is in the magnetic sheet surface, the central magnetic sheet is isolated from the outer ring magnetic sheet through a gap, so that the long-free-path eddy current cannot appear on the central magnetic sheet. Compared with the traditional shielding plate, the shielding plate has the advantages that through simulation, the number of the outer ring magnetic sheets and the central magnetic sheets in the stacking mode is smaller under the condition of the same shielding performance, so that the miniaturization and the lightness of the shielding plate are facilitated, and meanwhile, the module charging efficiency and the saturation current are improved; and no 'air gap' or 'insulation crack' process is required to be additionally added into the material, so that the process procedure can be shortened, the yield of products is improved, and the production cost of the wireless charging module is reduced.

Drawings

Fig. 1 is a cross-sectional view of a wireless charging module according to a first embodiment of the invention;

fig. 2 is a schematic diagram of a wireless charging module according to a first embodiment of the present invention;

fig. 3 is a top view of a wireless charging module according to a first embodiment of the invention (after the first adhesive layer is hidden);

fig. 4 is a top view of the wireless charging module according to the second embodiment of the invention (after the first adhesive layer is hidden);

fig. 5 is a top view of a wireless charging module with another structure according to a second embodiment of the present invention (after the first adhesive layer is hidden);

fig. 6 is a top view of a wireless charging module with another structure according to a second embodiment of the present invention (after the first adhesive layer is hidden);

fig. 7 is a top view of a wireless charging module with another structure according to a second embodiment of the present invention (after the first adhesive layer is hidden);

fig. 8 is a top view of a wireless charging module with another structure according to a second embodiment of the present invention (after the first adhesive layer is hidden);

fig. 9 is a top view of the wireless charging module according to the third embodiment of the invention (after the first adhesive layer is hidden);

fig. 10 is a top view of a wireless charging module with another structure according to a third embodiment of the invention (after the first adhesive layer is hidden);

fig. 11 is a top view of the wireless charging module according to the fourth embodiment of the invention (after the first adhesive layer is hidden);

fig. 12 is a top view of the wireless charging module according to the fifth embodiment of the invention (after the first adhesive layer is hidden).

Description of reference numerals:

1. a charging coil; 2. an outer ring magnetic sheet; 3. a central magnetic sheet; 4. a through hole; 5. a gap; 6. a first magnetically permeable layer; 7. a second magnetically permeable layer; 8. a first cutting pattern; 9. an insulating glue layer; 10. an inner edge surface; 11. a first glue layer; 12. a second adhesive layer; 13. a third adhesive layer; 14. and a second cutting pattern.

Detailed Description

In order to explain technical contents, achieved objects, and effects of the present invention in detail, the following description is made with reference to the accompanying drawings in combination with the embodiments.

The nanocrystalline strip is a nanocrystalline magnetically soft alloy strip; the amorphous strip is an amorphous soft magnetic alloy strip; metallic soft magnetic strips include, but are not limited to, commercially pure iron strips, Fe-Si strips, permalloy strips, and the like.

Referring to fig. 1 to 12, a shielding plate for a wireless charging module includes an outer ring magnetic sheet 2 and a central magnetic sheet 3, the outer ring magnetic sheet 2 is provided with a through hole 4, the central magnetic sheet 3 is disposed in the through hole 4, and a gap 5 is formed between a peripheral wall of the central magnetic sheet 3 and a wall surface of the through hole 4; the outer ring magnetic sheet 2 comprises at least one first magnetic conduction layer 6, and the first magnetic conduction layer 6 is a nanocrystalline strip, an amorphous strip or a metal soft magnetic strip; the central magnetic sheet 3 comprises at least one second magnetic conduction layer 7, and the second magnetic conduction layer 7 is a nanocrystalline strip, an amorphous strip or a metal soft magnetic strip.

The structure/working principle of the invention is briefly described as follows: magnetic lines of force parallel to the outer ring magnetic sheet 2 can induce the outer ring magnetic sheet 2 to generate eddy currents vertical to the outer ring magnetic sheet 2, and the outer ring magnetic sheet 2 cannot generate large eddy currents due to the fact that the thickness of a nanocrystalline strip, an amorphous strip or a metal soft magnetic strip in the outer ring magnetic sheet 2 is very thin (only 10-30 micrometers), and insulating polymer glue exists between layers; although the loss of the central magnetic sheet 3 which is not fragmented can be slightly increased, the higher magnetic conductivity can improve the magnetic gathering capacity of the central magnetic sheet 3, so that the charging efficiency is greatly improved, and meanwhile, the process is simple without adding other process steps.

From the above description, the beneficial effects of the present invention are: because the outer ring magnetic sheet 2 is vertical to the direction of the induced eddy current, when the outer ring magnetic sheet 2 is laminated by a plurality of first magnetic conduction layers 6, an insulating glue is arranged between the laminated first magnetic conduction layers 6, so no matter how high the magnetic loss mu' of the outer ring magnetic sheet 2 is, a long free path eddy current cannot be generated (when the outer ring magnetic sheet 2 is only provided with one first magnetic conduction layer 6, the single-layer first magnetic conduction layer 6 is thinner (the thickness is less than or equal to 30 mu m), the long free path eddy current cannot be generated), and therefore, the outer ring magnetic sheet 2 not only maintains ultrahigh magnetic conductivity, but also has lower eddy current loss; in addition, although the eddy current generated in the center magnet piece 3 by the magnetic field is in the magnet piece surface, the center magnet piece 3 is separated from the outer ring magnet piece 2 by the gap 5, so that the long-free-path eddy current does not appear on the center magnet piece 3. Compared with the traditional shielding piece, the shielding piece has the advantages that through simulation, the number of the outer ring magnetic pieces 2 and the central magnetic pieces 3 which are stacked is less under the condition of the same shielding performance, so that the miniaturization and the lightness of the shielding piece are facilitated, and meanwhile, the module charging efficiency and the saturation current are improved; and no 'air gap' or 'insulation crack' process is required to be additionally added into the material, so that the process procedure can be shortened, the yield of products is improved, and the production cost of the wireless charging module is reduced.

Further, the outer ring magnetic sheet 2 and the central magnetic sheet 3 have the same thickness.

Furthermore, the material of first magnetic conduction layer 6 is the same with the material of second magnetic conduction layer 7, outer lane magnetic sheet 2 with center magnetic sheet 3 is by the cutting shaping of same magnetic conduction piece.

Further, the material of the first magnetic conduction layer 6 is different from the material of the second magnetic conduction layer 7.

As can be seen from the above description, the material of the first magnetic conduction layer 6 and the material of the second magnetic conduction layer 7 may be the same or different, and preferably, they are the same for easy procurement and manufacture.

The material of the first magnetic conduction layer 6 is the same as that of the second magnetic conduction layer 7, and in the processing process, the central magnetic sheet 3 and the outer ring magnetic sheet 2 can be obtained simultaneously by directly cutting the gap 5 on the magnetic conduction sheet in cutting modes such as mechanical cutting, laser cutting and the like, so that the production efficiency of the shielding sheet is greatly improved, and the manufacturing cost of the shielding sheet is effectively reduced; when the material of the first magnetic conduction layer 6 is different from that of the second magnetic conduction layer 7, the central magnetic sheet 3 is directly cut out of the magnetic conduction sheet in cutting modes such as mechanical cutting, laser cutting and the like, the outer ring magnetic sheet 2 is cut out of the other magnetic conduction sheet with different materials, and then the two magnetic conduction sheets are combined. It is easy to understand that, when the first magnetic conduction layer and the second magnetic conduction layer are made of the same material (for example, both are made of nanocrystalline material), the central magnetic sheet 3 and the outer magnetic sheet 2 may also be cut from different magnetic conduction sheets, specifically, the central magnetic sheet 3 is directly cut from one magnetic conduction sheet by cutting methods such as mechanical cutting, laser cutting and the like, the outer magnetic sheet 2 is cut from the other magnetic conduction sheet made of the same material, and then the two magnetic conduction layers are assembled together.

Furthermore, a first cutting pattern 8 is arranged on the central magnetic sheet 3, and each second magnetic conduction layer 7 is respectively cut into a plurality of first small blocks by the first cutting pattern 8.

As can be seen from the above description, when the slit 5 is cut, the center magnetic sheet 3 can be selectively cut to a certain extent, so that the center magnetic sheet 3 can be fragmented, the magnetic loss of the center magnetic sheet 3 is reduced, and the charging efficiency is further improved.

Further, a second cutting pattern 14 is arranged on the outer ring magnetic sheet 2, and each first magnetic conduction layer 6 is respectively cut into a plurality of second small pieces by the second cutting pattern 14.

It can be known from the above description, when cutting gap 5, can select to carry out the cutting of certain degree to outer lane magnetic sheet 2 for outer lane magnetic sheet 2 forms the effect of class fragmentation, thereby reduces outer lane magnetic sheet 2's magnetic loss, does benefit to further improvement charge efficiency.

Further, the outer ring magnetic sheet 2 comprises a plurality of first magnetic conduction layers 6 which are connected in a stacking mode through an insulating adhesive layer 9; and/or the central magnetic sheet 3 comprises a plurality of second magnetic conduction layers 7 which are connected in a stacking mode through an insulating adhesive layer 9.

From the above description, the thicknesses of the outer ring magnetic sheet 2 and the center magnetic sheet 3 can be selected according to actual needs.

Further, the top surface of the central magnetic sheet 3 and the top surface of the outer ring magnetic sheet 2 are coplanar and connected through a first adhesive layer 11; and/or the bottom surface of the central magnetic sheet 3 and the bottom surface of the outer ring magnetic sheet 2 are coplanar and connected through a second adhesive layer 12.

Further, the gap 5 is filled with air or a non-magnetic material.

As can be seen from the above description, the non-magnetic material includes, but is not limited to, non-magnetic glue, non-magnetic film, non-magnetic paper, and the like.

Wireless module of charging includes charging coil 1, still includes above-mentioned wireless shielding piece for the module that charges, central magnetic sheet 3 corresponds to charging coil 1's hollow region sets up.

As can be seen from the above description, the wireless charging module has the advantages of high charging efficiency and low manufacturing cost. Charging coil 1 can select to bond in the bottom surface of outer lane magnetic sheet 2.

Further, the inner edge surface 10 of the charging coil 1 is coplanar with the peripheral wall of the central magnetic sheet 3.

Known from the above description, the magnetic leakage can be prevented to the inner fringe face 10 of charging coil 1 and the perisporium coplane of central magnetic sheet 3, passes on the magnetic line of force of 1 hollow area of charging coil directly wears outer lane magnetic sheet 2 promptly, does benefit to the magnetism gathering performance who guarantees central magnetic sheet 3, ensures the charge efficiency of wireless charging module. As can be easily understood, the inner edge surface 10 of the charging coil 1 is an inner diameter surface of the charging coil 1, which is a continuous annular surface perpendicular to the outer ring magnetic sheet 2.

Example one

Referring to fig. 1 to 5, a first embodiment of the present invention is: referring to fig. 1 to 3, the wireless charging module includes a charging coil 1 and a shielding plate for the wireless charging module, in this embodiment, the charging coil 1 is adhered to the bottom of the shielding plate for the wireless charging module.

The shielding sheet for the wireless charging module comprises an outer ring magnetic sheet 2 which is not subjected to fragmentation treatment and a central magnetic sheet 3 which is not subjected to fragmentation treatment, wherein a through hole 4 is formed in the outer ring magnetic sheet 2, the central magnetic sheet 3 is arranged in the through hole 4 and corresponds to the hollow area of the charging coil 1, and a gap 5 is formed between the peripheral wall of the central magnetic sheet 3 and the wall surface of the through hole 4; the outer ring magnetic sheet 2 comprises at least one first magnetic conduction layer 6, and the first magnetic conduction layer 6 is a nanocrystalline strip, an amorphous strip or a metal soft magnetic strip; the central magnetic sheet 3 comprises at least one second magnetic conduction layer 7, and the second magnetic conduction layer 7 is a nanocrystalline strip, an amorphous strip or a metal soft magnetic strip. The slit 5 is in the form of a continuous complete ring.

Further, the gap 5 is filled with air or a non-magnetic material, and the non-magnetic material may be some non-magnetic substances such as non-magnetic colloid (e.g., polymer insulating glue), non-magnetic film, non-magnetic paper, and the like.

In order to facilitate the processing and reduce the manufacturing cost of the shielding plate and the wireless charging module, in this embodiment, the material of the first magnetic conduction layer 6 is the same as that of the second magnetic conduction layer 7, the thickness of the outer ring magnetic sheet 2 is the same as that of the central magnetic sheet 3, and the outer ring magnetic sheet 2 and the central magnetic sheet 3 are formed by cutting the same magnetic conduction sheet. It is easy to understand that in other embodiments, the material of the first magnetic conduction layer 6 and the material of the second magnetic conduction layer 7 may be different, in other words, the central magnetic sheet 3 and the outer magnetic sheet 2 are cut from magnetic conduction sheets of different materials, for example, the material of the first magnetic conduction layer 6 is an amorphous strip, and the material of the second magnetic conduction layer 7 is a nanocrystalline strip; likewise, outer lane magnetic sheet 2 also can be different with 3 thickness of center magnetic sheet, for example the thickness of center magnetic sheet 3 is greater than the thickness of outer lane magnetic sheet 2, so make partly can stretch into the hollow area of charging coil 1 of central magnetic sheet 3 in to improve the shielding performance of center magnetic sheet 3, further improve the charge efficiency of wireless charging module.

Preferably, the outer ring magnetic sheet 2 comprises a plurality of first magnetic conduction layers 6 which are connected in a stacking mode through an insulating adhesive layer 9; and/or the central magnetic sheet 3 comprises a plurality of second magnetic conduction layers 7 which are connected in a stacking mode through an insulating adhesive layer 9. Further preferably, the number of the first magnetic conduction layers 6 is two or three, and the number of the second magnetic conduction layers 7 is two or three. In this embodiment, the first and second magnetic conductive layers are respectively a nanocrystalline strip, and the thickness of the nanocrystalline strip is 10-30 μm.

For guaranteeing central magnetic sheet 3 gather the magnetic effect, prevent the magnetic leakage, further improve wireless charging module's charging efficiency, it is preferred, charging coil 1's interior edge face 10 and central magnetic sheet 3's perisporium coplane. As can be easily understood, the inner edge surface 10 of the charging coil 1 is annular, and each point of the wireless charging coil 1 closest to its own central axis is located on the inner edge surface 10.

The top surface of the central magnetic sheet 3 and the top surface of the outer ring magnetic sheet 2 are coplanar and connected through a first adhesive layer 11; and/or the bottom surface of the central magnetic sheet 3 and the bottom surface of the outer ring magnetic sheet 2 are coplanar and connected through a second adhesive layer 12. The first adhesive layer 11 and the second adhesive layer 12 are respectively insulating adhesive, and in this embodiment, the first adhesive layer 11 and the second adhesive layer 12 are respectively acrylic adhesive layers.

Because the outer ring magnetic sheet 2 is vertical to the direction of the induced eddy current, the thickness of the magnetic sheet is thinner, and the insulating glue layer 9 is arranged between the stacked nanocrystalline strips, no matter how high the magnetic loss mu' of the outer ring magnetic sheet 2 is, the long free path eddy current can not be generated, so the outer ring magnetic sheet 2 can maintain the ultrahigh magnetic conductivity without generating high eddy current loss; in addition, although the eddy current generated by the magnetic field in the central magnetic sheet 3 is in the magnetic sheet surface, the charging efficiency is greatly improved due to the high magnetic permeability, and the module loss is reduced. And the central magnetic sheet 3 and the outer ring magnetic sheet 2 are formed by cutting the same magnetic conductive sheet, so that the process is simpler, other process steps are not required to be added, and the cost is saved. Compared with the traditional magnetic shielding sheet, the shielding sheet does not need a process of adding air gaps or insulation cracks in materials, can shorten the process procedure, and simultaneously has less laminated magnetic conduction layers under the condition of the same shielding performance, thereby being beneficial to the miniaturization and the lightness of the shielding sheet; meanwhile, the charging efficiency and the saturation current are improved.

The above-mentioned method for manufacturing wireless charging module (for example, the material of the nano-crystalline strip),

step 1: providing a nanocrystalline strip, and carrying out heat treatment on the nanocrystalline strip;

step 2: coating the nanocrystalline strip subjected to the step 1 with glue;

and step 3: laminating N glued nanocrystalline strips, and bonding two adjacent nanocrystalline strips to obtain a nanocrystalline magnetic sheet (namely the magnetic conductive sheet), wherein N is an integer greater than or equal to 1; preferably, N is 2 or 3.

And 4, step 4: carrying out contour cutting and slit 5 cutting on the nanocrystalline magnetic sheet to obtain an outer ring magnetic sheet 2 and a central magnetic sheet 3;

and 7: the top surface of the central magnetic conductive sheet and the top surface of the outer ring magnetic sheet 2 are attached to the same adhesive layer (i.e. the first adhesive layer 11).

The back is installed with charging coil 1 to the assembler, and charging coil 1's top surface laminating is in the bottom of outer circle magnetic sheet 2 promptly, and after charging coil 1's inner peripheral face 10 and the perisporium coincidence of central magnetic sheet 3, still need laminate charging coil 1's bottom surface, central magnetic sheet 3's bottom surface on an insulating layer (on third glue film 13 promptly) to accomplish the preparation of wireless module of charging.

The inventors manufactured a batch of samples and tested the samples.

Nanocrystalline alloy strip grade: 1K107b, thickness 20 μm.

The nanocrystalline ribbon is heat-treated using a heat treatment furnace (e.g., a nitrogen gas furnace). The heat treatment process comprises the following steps: firstly, heating the nanocrystalline strip to 550 ℃ along with a furnace, then carrying out heat preservation for 2 hours, cooling to room temperature at the speed of 600 ℃/h, and discharging.

Coating the single side of the strip subjected to heat treatment with glue; and (3) attaching the nanocrystalline strip coated with the glue on the single surface to obtain a 3-layer nanocrystalline chip (namely the magnetic conductive sheet).

Die cutting is carried out on the obtained nano-crystal plate, die cutting gaps 5 are carried out on 3 layers of nano-crystal plates according to the external dimension of the wireless charging module and the internal diameter dimension of the charging coil 1, and a high-permeability nano-crystal magnetic material (namely a central magnetic sheet 3) positioned in the center is reserved to obtain a shielding sheet;

and (3) testing: and assembling the prepared sample 1, a charging coil 1 and other components to obtain a wireless charging module, and testing the electrical property of the wireless charging module. In order to better compare with the shielding plate manufactured by the traditional process, the inventor also adds a wireless charging module corresponding to the 4-layer nanocrystalline shielding plate manufactured by the traditional process as a comparison group, and the test results of the sample are shown in table 1.

Table 1 comparative table of test results of samples

Sample numbering	Coil inductance L/muH	Quality factor Q	AC resistance Rs/m omega
				Sample
1	8.11	23.83	214.46
				Control group	8.02	19.88	251.21

As can be seen from table 1, the inductance of sample 1 is higher than that of the control group as a whole, and the Q value is also increased to some extent, and the ac loss is also decreased to some extent.

Next, the saturation current performance test comparison between the sample 1 and the control group is performed by using the saturation current testing platform, and the test results are shown in table 2.

Table 2 saturation current test comparison table

As shown in table 2, the saturation current performance of sample 1 was much higher than the control by saturation current comparative analysis.

Finally, the charging efficiency test comparison between sample 1 and the control group was performed using a 15W platform, and the test results are shown in table 3.

Table 315W platform charging efficiency test comparison table

As shown in table 3, the charging efficiency of sample 1 was much higher than that of the control group by comparative analysis of the charging efficiency.

Example two

Referring to fig. 4 to 8, the second embodiment of the present invention is an improved solution based on the first embodiment, and is different from the first embodiment only in that the center pole piece 3 has a first cutting pattern 8, specifically: the central magnetic sheet 3 is provided with a first cutting pattern 8, the first cutting pattern 8 is used for cutting each second magnetic conduction layer 7 into a plurality of first small blocks respectively, and the first cutting pattern 8 comprises a plurality of cutting wire grooves. Alternatively, the cutting line grooves of the first cutting pattern 8 may be filled with air or a non-magnetic material like the slits 5. The arrangement of the first cutting patterns 8 on the central magnetic sheet 3 can enable the central magnetic sheet 3 to obtain a fragmentation effect, so that the charging efficiency is improved.

In the processing, the first cutting pattern 8 may be processed while the slit 5 is cut, and in this embodiment, the first cutting pattern 8 is formed in a grid shape, and in other embodiments, the first cutting pattern 8 may be formed in a cross shape (as shown in fig. 5), a cross shape (as shown in fig. 6), a radial shape (as shown in fig. 7), an oblique shape (as shown in fig. 8), or the like.

The inventors manufactured sample 2 and tested sample 2.

Nanocrystalline alloy strip grade: 1K107b, thickness 20 μm.

Die cutting is carried out on the obtained nano-crystal plate, die cutting gaps 5 are carried out on 3 layers of nano-crystal plates according to the external dimension of the wireless charging module design and the internal diameter dimension of the charging coil 1, meanwhile, the grid-shaped first cutting pattern 8 is die cut, and the high-permeability nano-crystal magnetic material (namely the central magnetic sheet 3) positioned in the center is reserved, so that the shielding sheet is obtained; it should be noted that by designing the specific structure of the die cutter on the die cutting device, the gap 5 and the first cutting pattern 8 can be die-cut simultaneously when the nano-chip is die-cut;

and (3) testing: and assembling the prepared sample 2, the charging coil 1 and other components to obtain a wireless charging module, and testing the electrical property of the wireless charging module. For better comparison with the shielding plate made by the conventional process, the inventors also added sample 1 of example one to form a comparison, and the test results of the sample are shown in table 4.

Table 4 comparative table of sample test results

Sample numbering	Coil inductance L/muH	Quality factor Q	AC resistance Rs/m omega
				Sample
1	8.11	23.83	214.46
				Sample 2	8.05	23.94	208.72

As can be seen from table 4, the inductance of sample 2 is slightly lower than that of sample 1, but the Q value is increased to some extent, and the ac loss is decreased to some extent.

Next, the saturation current performance test comparison was performed on sample 1 and sample 2 using the saturation current test platform, and the test results are shown in table 5.

TABLE 5 comparison table for saturation current test

As shown in table 5, the saturation current performance of sample 2 is slightly higher overall than that of sample 1 by the saturation current comparative analysis.

Finally, the charging efficiency test comparison was performed on sample 1 and sample 2 using a 15W platform, and the test results are shown in table 6.

Table 615W platform charging efficiency test comparison table

As shown in table 6, the charging efficiency of sample 2 was slightly higher than that of sample 1 by comparative analysis of the charging efficiency.

EXAMPLE III

Referring to fig. 9 and 10, a third embodiment of the present invention is an improved solution based on the first embodiment, and is different from the first embodiment only in that the outer ring magnetic sheet 2 has a second cutting pattern 14, specifically: and a second cutting pattern 14 is arranged on the outer ring magnetic sheet 2, each first magnetic conduction layer 6 is respectively cut into a plurality of second small blocks by the second cutting pattern 14, and the second cutting pattern 14 comprises a plurality of cutting wire grooves. Alternatively, the cutting line grooves of the second cutting pattern 14 may be filled with air or a non-magnetic material like the slits 5. The second cutting pattern 14 on the outer ring magnetic sheet 2 can enable the outer ring magnetic sheet 2 to obtain a fragmentization effect, so that the charging efficiency is improved.

In the processing, the second cut pattern 14 may be processed while the slit 5 is being cut, and in this embodiment, the second cut pattern 14 may be formed in a shape of a Chinese character 'mi', and in other embodiments, the second cut pattern 14 may be formed in a shape of a cross, a radial shape (as shown in fig. 10), an oblique shape, or the like.

The inventors manufactured sample 3 and tested sample 3.

Nanocrystalline alloy strip grade: 1K107b, thickness 20 μm.

Die cutting is carried out on the obtained nano-crystal plate, die cutting gaps 5 are carried out on 3 layers of nano-crystal plates according to the external dimension of the wireless charging module design and the internal diameter dimension of the charging coil 1, meanwhile, a second cutting pattern 14 in a shape like a Chinese character 'mi' is die cut, and a high-permeability nano-crystal magnetic material (namely a central magnetic sheet 3) positioned in the center is reserved, so that a shielding sheet is obtained; it should be noted that by designing the specific structure of the die cutter on the die cutting device, the gap 5 and the second cutting pattern 14 can be die-cut simultaneously when the nano-wafer is die-cut;

and (3) testing: and assembling the prepared sample 3, the charging coil 1 and other components to obtain a wireless charging module, and testing the electrical property of the wireless charging module. For better comparison with the shielding plate made by the conventional process, the inventors also added sample 1 of example one to form a comparison, and the test results of the sample are shown in table 7.

TABLE 7 comparative table of test results of samples

Sample numbering	Coil inductance L/muH	Quality factor Q	AC resistance Rs/m omega
				Sample
1	8.11	23.83	214.46
				Sample 3	8.03	24.09	209.45

As can be seen from table 7, sample 3 has a slightly lower inductance than sample 1, but has a certain increase in Q value and a certain decrease in ac loss.

Next, the saturation current performance test comparison was performed on sample 1 and sample 3 using the saturation current test platform, and the test results are shown in table 8.

Table 8 saturation current test comparison table

As shown in table 8, the saturation current performance of sample 3 is slightly higher overall than that of sample 1 by the saturation current comparative analysis.

Finally, the charging efficiency test comparison was performed on sample 1 and sample 3 using a 15W platform, and the test results are shown in table 9.

Table 915W platform charging efficiency test comparison table

As shown in table 9, the charging efficiency of sample 3 was slightly higher than that of sample 1 by comparative analysis of the charging efficiency.

Example four

Referring to fig. 11, a fourth embodiment of the present invention is an improvement on the first embodiment, and is different from the first embodiment only in that the center piece 3 has a first cutting pattern 8 and the outer ring piece 2 has a second cutting pattern 14, specifically: a first cutting pattern 8 is arranged on the central magnetic sheet 3, each second magnetic conduction layer 7 is respectively cut into a plurality of first small blocks by the first cutting pattern 8, and the first cutting pattern 8 comprises a plurality of cutting wire grooves; and a second cutting pattern 14 is arranged on the outer ring magnetic sheet 2, each first magnetic conduction layer 6 is respectively cut into a plurality of second small blocks by the second cutting pattern 14, and the second cutting pattern 14 comprises a plurality of cutting wire grooves. Alternatively, the cutting line grooves of the first cutting pattern 8 and the cutting line grooves of the second cutting pattern 14 may be filled with air or a non-magnetic material as in the case of the slit 5.

During machining, the first cutting pattern 8 and the second cutting pattern 14 can be machined while the slit 5 is being cut. Optionally, the first cutting pattern 8 is in a grid shape, a cross shape, a rice shape, a radial shape, an oblique shape, or the like; the second cut pattern 14 has a shape such as a square, a radial, or an oblique shape.

The inventors manufactured sample 4 and tested sample 4.

Nanocrystalline alloy strip grade: 1K107b, thickness 20 μm.

Die cutting is carried out on the obtained nano-crystal plate, die cutting gaps 5 are carried out on 3 layers of nano-crystal plates according to the external dimension designed by the wireless charging module and the internal diameter dimension of the charging coil 1, meanwhile, a first cutting graph 8 in a grid shape and a second cutting graph 14 in a shape like a Chinese character 'mi' are die cut, and a high-permeability nano-crystal magnetic material (namely a central magnetic sheet 3) positioned in the center is reserved to obtain a shielding sheet;

and (3) testing: and assembling the prepared sample 4, the charging coil 1 and other components to obtain a wireless charging module, and testing the electrical property of the wireless charging module. For better comparison with the shielding plate made by the conventional process, the inventors also added sample 1 of example one to form a comparison, and the test results of the sample are shown in table 10.

TABLE 10 comparative table of test results of samples

Sample numbering	Coil inductance L/muH	Quality factor Q	AC resistance Rs/m omega
				Sample
1	8.11	23.83	214.46
				Sample No. 4	8.08	24.27	209.21

As can be seen from table 10, sample 4 has a slightly lower inductance than sample 1, but the Q value is increased to some extent, and the ac loss is decreased to some extent.

Next, the saturation current performance test comparison was performed on sample 1 and sample 4 using the saturation current test platform, and the test results are shown in table 11.

TABLE 11 comparison table for saturation current test

As shown in table 11, the saturation current performance of sample 4 is slightly higher overall than that of sample 1 by the saturation current comparative analysis.

Finally, the charging efficiency test comparison was performed on sample 1 and sample 4 using a 15W platform, and the test results are shown in table 12.

Table 1215W platform charging efficiency test comparison table

As shown in table 12, the charging efficiency of sample 4 was slightly higher than that of sample 1 by comparative analysis of the charging efficiency.

EXAMPLE five

Referring to fig. 12, a fifth embodiment of the present invention is an improved solution based on the first embodiment, and is different from the first embodiment only in that the center piece 3 has a first cutting pattern 8 and the outer ring piece 2 has a second cutting pattern 14, specifically: a first cutting pattern 8 is arranged on the central magnetic sheet 3, each second magnetic conduction layer 7 is respectively cut into a plurality of first small blocks by the first cutting pattern 8, and the first cutting pattern 8 comprises a plurality of cutting wire grooves; and a second cutting pattern 14 is arranged on the outer ring magnetic sheet 2, each first magnetic conduction layer 6 is respectively cut into a plurality of second small blocks by the second cutting pattern 14, and the second cutting pattern 14 comprises a plurality of cutting wire grooves. Alternatively, the cutting line grooves of the first cutting pattern 8 and the cutting line grooves of the second cutting pattern 14 may be filled with air or a non-magnetic material as in the case of the slit 5.

The inventors manufactured sample 5 and tested sample 5.

Nanocrystalline alloy strip grade: 1K107b, thickness 20 μm.

Die cutting is carried out on the obtained nano-crystal plate, die cutting gaps 5 are carried out on 3 layers of nano-crystal plates according to the external dimension designed by the wireless charging module and the internal diameter dimension of the charging coil 1, meanwhile, a first cutting graph 8 in a shape of a Chinese character 'mi' and a second cutting graph 14 in a shape of a Chinese character 'mi' are die cut, and a high-permeability nano-crystal magnetic material (namely a central magnetic sheet 3) positioned in the center is reserved to obtain a shielding sheet;

and (3) testing: and assembling the prepared sample 5, the charging coil 1 and other components to obtain a wireless charging module, and testing the electrical property of the wireless charging module. For better comparison with the shielding plate made by the conventional process, the inventors also added sample 1 of example one to form a comparison, and the test results of the sample are shown in table 13.

TABLE 13 comparative table of test results of samples

As can be seen from table 13, sample 5 has a slightly lower inductance than sample 1, but has a certain increase in Q value and a certain decrease in ac loss.

Next, the saturation current performance test comparison was performed on sample 1 and sample 5 using the saturation current test platform, and the test results are shown in table 14.

TABLE 14 saturation current test COMPARATIVE TABLE

As shown in table 14, the saturation current performance of sample 5 is slightly higher overall than that of sample 1 by the saturation current comparative analysis.

Finally, the charging efficiency test comparison was performed on sample 1 and sample 5 using a 15W platform, and the test results are shown in table 15.

TABLE 1515W PLATFORM CHARGING EFFICIENCY TEST COMPARATIVE TABLE

As shown in table 15, the charging efficiency of sample 5 was slightly higher than that of sample 1 by comparative analysis of the charging efficiency.

In summary, compared with the conventional magnetic shielding plate and the conventional charging module, the shielding plate for the wireless charging module and the wireless charging module provided by the invention have the advantages that the charging efficiency and the saturation current of the wireless charging module are improved under the condition of the same shielding performance; in addition, the traditional 'broken magnetic' process is not needed in the production process of the shielding sheet, so that the manufacturing process of the shielding sheet is reduced, and the manufacturing cost of the shielding sheet is reduced.

The above description is only an embodiment of the present invention, and not intended to limit the scope of the present invention, and all equivalent changes made by using the contents of the present specification and the drawings, or applied directly or indirectly to the related technical fields, are included in the scope of the present invention.

Claims

1. The utility model provides a wireless shielding piece for module that charges which characterized in that: the magnetic disc comprises an outer ring magnetic disc and a center magnetic disc, wherein the outer ring magnetic disc is provided with a through hole, the center magnetic disc is arranged in the through hole, and a gap is formed between the peripheral wall of the center magnetic disc and the wall surface of the through hole; the outer ring magnetic sheet comprises at least one first magnetic conduction layer, and the first magnetic conduction layer is a nanocrystalline strip, an amorphous strip or a metal soft magnetic strip; the central magnetic sheet comprises at least one second magnetic conduction layer, and the second magnetic conduction layer is a nanocrystalline strip, an amorphous strip or a metal soft magnetic strip.

2. The wireless shielding piece for charging module of claim 1, wherein: the outer ring magnetic sheet and the central magnetic sheet have the same thickness.

3. The wireless shielding piece for charging module of claim 1, wherein: the material of first magnetic conduction layer is the same with the material of second magnetic conduction layer, outer lane magnetic sheet with the center magnetic sheet is by the cutting shaping of same magnetic conduction piece.

4. The wireless shielding piece for charging module of claim 1, wherein: the material of the first magnetic conduction layer is different from that of the second magnetic conduction layer.

5. The wireless shielding piece for charging module of claim 1, wherein: the central magnetic sheet is provided with a first cutting pattern, and each second magnetic conduction layer is respectively cut into a plurality of first small blocks by the first cutting pattern.

6. The wireless shielding piece for charging module of claim 1, wherein: and the outer ring magnetic sheet is provided with a second cutting pattern, and each first magnetic conduction layer is respectively cut into a plurality of second small blocks by the second cutting pattern.

7. The wireless shielding piece for charging module of claim 1, wherein: the top surface of the central magnetic sheet and the top surface of the outer ring magnetic sheet are coplanar and connected through a first adhesive layer; and/or the bottom surface of the central magnetic sheet is coplanar with the bottom surface of the outer ring magnetic sheet and is connected with the bottom surface of the outer ring magnetic sheet through a second adhesive layer.

8. The wireless shielding piece for charging module of claim 1, wherein: the gap is filled with air or non-magnetic materials.

9. Wireless module that charges, including the charging coil, its characterized in that: the shielding sheet for the wireless charging module of any one of claims 1 to 8, wherein the central magnetic sheet is arranged corresponding to the hollow area of the charging coil.

10. The wireless charging module of claim 9, wherein: the inner edge surface of the charging coil is coplanar with the peripheral wall of the central magnetic sheet.