Magnetic core and magnetic element comprising same
The present invention relates to a magnetic core capable of precisely maintaining the size of a gap, and to a magnetic element comprising same. A magnetic core according to one embodiment comprises: an upper core having at least a first outer leg and a second outer leg; a lower core having at least a third outer leg facing the first outer leg and a fourth outer leg facing the second outer leg; outer leg gap parts disposed between the first outer leg and the third outer leg, and between the second outer leg and the fourth outer leg. The outer leg gap parts may comprise: an adhesive; and a plurality of spherical fillers dispersed in the adhesive.
1 . A magnetic core, comprising:
an upper core having at least a first outer leg and a second outer leg;
a lower core having at least a third outer leg facing the first outer leg and a fourth outer leg facing the second outer leg; and
an outer-leg gap portion disposed in each of a region between the first outer leg and the third outer leg and a region between the second outer leg and the fourth outer leg,
wherein the outer-leg gap portion comprises:
an adhesive; and
a plurality of spherical fillers disposed in the adhesive in a distributed form,
wherein the plurality of spherical fillers are made of a conductive material, making the upper core and the lower core be in an electrically shorted state wherein the spherical fillers are disposed in parallel to each other in a single layer and do not overlap each other in a thickness direction of the layer in the outer-leg gap portion.
2 . The magnetic core according to claim 1 , wherein an upper limit of a content of the spherical fillers in the outer-leg gap portion is determined in consideration of a planar area of the outer-leg gap portion with respect to an adhesive force of the adhesive, and
wherein a lower limit of the content of the spherical fillers in the outer-leg gap portion is determined in consideration of a length of a short side of each of the first outer leg, the second outer leg, the third outer leg, and the fourth outer leg and diameters of the spherical fillers.
3 . The magnetic core according to claim 1 , wherein the spherical fillers occupy 0.2% to 50% of a planar area of the outer-leg gap portion.
4 . The magnetic core according to claim 1 , wherein the upper core comprises a first center leg,
wherein the lower core comprises a second center leg facing the first center leg, and
wherein the first center leg and the second center leg form a center gap therebetween.
5 . The magnetic core according to claim 4 , wherein a length of the center gap is larger than a diameter of each of the plurality of spherical fillers.
6 . The magnetic core according to claim 4 , wherein a length of at least one of the first center leg and the second center leg is shorter than lengths of the first outer leg, the second outer leg, the third outer leg, and the fourth outer leg in a vertical direction.
7 . A magnetic element, comprising:
a magnetic core; and
at least one coil,
wherein the magnetic core comprises:
an upper core having at least a first outer leg and a second outer leg;
a lower core having at least a third outer leg facing the first outer leg and a fourth outer leg facing the second outer leg; and
an outer-leg gap portion disposed in each of a region between the first outer leg and the third outer leg and a region between the second outer leg and the fourth outer leg,
wherein the outer-leg gap portion comprises:
an adhesive; and
a plurality of spherical fillers disposed in the adhesive in a distributed form,
wherein the plurality of spherical fillers are made of a conductive material, making the upper core and the lower core be in an electrically shorted state wherein the spherical fillers are disposed in parallel to each other in a single layer and do not overlap each other in a thickness direction of the layer in the outer-leg gap portion.
8 . The magnetic core according to claim 4 , wherein sizes of the outer-leg gap portion and the center gap are determined depending on diameters of the spherical fillers.
9 . The magnetic core according to claim 1 , wherein the adhesive includes an epoxy resin.
10 . The magnetic core according to claim 1 , wherein each of the spherical filler includes an insulating material.
11 . The magnetic core according to claim 1 , wherein a diameter of each of the spherical fillers is determined in consideration of a target inductance.
12 . The magnetic core according to claim 1 , wherein a diameter of each of the spherical fillers corresponds to either a distance between a lower surface of the first outer leg and an upper surface of the third outer leg or a distance between a lower surface of the second outer leg and an upper surface of the fourth outer leg.
13 . The magnetic core according to claim 1 , wherein each of the spherical fillers has a rigidity to allow a height thereof to change within a predetermined range due to pressure applied thereto in a vertical direction.
14 . The magnetic core according to claim 1 , wherein at least one of the third or fourth outer leg is formed in a shape of a rectangular column.
15 . The magnetic core according to claim 1 , wherein the spherical fillers include at least two fillers disposed in a direction in which a short side of an upper surface of at least one of the third or fourth outer leg extends.
16 . The magnetic core according to claim 1 , wherein a ratio of a planar area of the adhesive to a planar area of the outer-leg gap portion is about 50% or more.