Shielding film, coil assembly, and wireless charging device
A shielding film includes a first film layer. The first film layer includes a first conductive part and a first insulating part, and the first insulating part penetrates the first conductive part in a thickness direction of the first film layer. Under electromagnetic influence of a first electromagnetic field, a first eddy current is formed in the first film layer, and a loop of the first eddy current is located in the first conductive part, so that the first eddy current has relatively high current intensity. Under electromagnetic influence of a second electromagnetic field, a second eddy current is formed in the first film layer, and a loop of the second eddy current passes through the first insulating part, so that current intensity of the second eddy current can be reduced.
1. A shielding film comprising a first film layer, wherein
the first film layer comprises a first conductive part and a first insulating part, and the first insulating part penetrates the first conductive part or the first conductive part penetrates the first insulating part in a thickness direction of the first film layer;
under the influence of a magnetic field of a first electromagnetic field, a first eddy current is formed in the first film layer, and a loop of the first eddy current is located in the first conductive part; and under the influence of a magnetic field of a second electromagnetic field, a second eddy current is formed in the first film layer, and a loop of the second eddy current passes through the first insulating part; and
a loop area of the first eddy current is less than a loop area of the second eddy current,
wherein the first insulating part constitutes a main part of the first film layer, a plurality of first conductive parts are disposed in the first film layer, and the plurality of first conductive parts penetrate the first insulating part in the thickness direction of the first film layer.
2. The shielding film according to claim 1 , further comprising a second film layer, wherein
the second film layer comprises a second conductive part and a second insulating part, and the second insulating part penetrates the second conductive part in a thickness direction of the second film layer;
the second film layer is attached to a side surface of the first film layer, and a projection of the second conductive part on the first film layer covers the first insulating part; and
under the influence of the magnetic field of the first electromagnetic field, a third eddy current is formed in the second film layer, and a loop of the third eddy current is located in the second conductive part; and under the influence of the magnetic field of the second electromagnetic field, a fourth eddy current is formed in the second film layer, and a loop of the fourth eddy current passes through the second insulating part.
3. The shielding film according to claim 2 , wherein the second conductive part constitutes a main part of the second film layer, a plurality of second insulating parts are disposed in the second film layer, and the plurality of second insulating parts penetrate the second conductive part in the thickness direction of the second film layer.
4. The shielding film according to claim 2 , wherein the second insulating part constitutes a main part of the second film layer, a plurality of second conductive parts are disposed in the second film layer, and the plurality of second conductive parts penetrate the second insulating part in the thickness direction of the second film layer.
5. The shielding film according to claim 2 , wherein the second film layer comprises any one of carbon fiber felt, a metal film, conductive paper, and a woven mesh.
6. The shielding film according to claim 2 , wherein the second insulating part constitutes a main part of the second film layer, a plurality of second conductive parts are disposed in the second film layer, and the plurality of second conductive parts penetrate the second insulating part in the thickness direction of the second film layer.
7. The shielding film according to claim 1 , wherein the first film layer comprises any one of carbon fiber felt, a metal film, conductive paper, or a woven mesh.
8. The shielding film according to claim 1 , further comprising a thermally conductive insulation layer, wherein the thermally conductive insulation layer is attached to at least one side surface of the first film layer.
9. A coil assembly, comprising an inductor coil and the shielding film according to claim 1 , wherein
the shielding film is earthed and disposed on at least one side of the inductor coil; and
the inductor coil is configured to generate the first electromagnetic field and the second electromagnetic field.
10. An electronic device comprising a housing and an electrical component located in the housing, and further comprising a shielding film,
wherein the shielding film comprises a first film layer comprising a first conductive part and a first insulating part,
wherein under the influence of a magnetic field of a first electromagnetic field, a first eddy current is formed in the first film layer, and a loop of the first eddy current is located in the first conductive part; and under the influence of a magnetic field of a second electromagnetic field, a second eddy current is formed in the first film layer, and a loop of the second eddy current passes through the first insulating part,
wherein a loop area of the first eddy current is less than a loop area of the second eddy current, and
wherein
the shielding film is disposed on at least a part of a periphery of the electrical component,
wherein the first insulating part constitutes a main part of the first film layer, a plurality of first conductive parts are disposed in the first film layer, and the plurality of first conductive parts penetrate the first insulating part in the thickness direction of the first film layer.
11. A shielding film comprising a first film layer, wherein
the first film layer comprises a first conductive part and a first insulating part, and the first insulating part penetrates the first conductive part or the first conductive part penetrates the first insulating part in a thickness direction of the first film layer;
under the influence of a magnetic field of a first electromagnetic field, a first eddy current is formed in the first film layer, and a loop of the first eddy current is located in the first conductive part; and under the influence of a magnetic field of a second electromagnetic field, a second eddy current is formed in the first film layer, and a loop of the second eddy current passes through the first insulating part; and
a loop area of the first eddy current is less than a loop area of the second eddy current,
further comprising a second film layer, wherein
the second film layer comprises a second conductive part and a second insulating part, and the second insulating part penetrates the second conductive part in a thickness direction of the second film layer;
the second film layer is attached to a side surface of the first film layer, and a projection of the second conductive part on the first film layer covers the first insulating part; and
under the influence of the magnetic field of the first electromagnetic field, a third eddy current is formed in the second film layer, and a loop of the third eddy current is located in the second conductive part; and under the influence of the magnetic field of the second electromagnetic field, a fourth eddy current is formed in the second film layer, and a loop of the fourth eddy current passes through the second insulating part,
wherein the second insulating part constitutes a main part of the second film layer, a plurality of second conductive parts are disposed in the second film layer, and the plurality of second conductive parts penetrate the second insulating part in the thickness direction of the second film layer.