JPH04137506A - Plane inductance element - Google Patents

Abstract

PURPOSE:To allow part of a magnetic flux generated by a planar spiral winding to pass through a magnetic substance at the central section of the planar spiral winding so that the inductance and performance of a plane inductance element can be improved by arranging the magnetic substance in a space formed at the central part of the planar spiral winding. CONSTITUTION:Each planar spiral winding 11 is constituted by forming a conductor 11a to a, for example, circular spiral in nearly the same plane and a center core 14 formed to a solid cylindrical shape of a magnetic substance, such as ferrite, amorphous, etc., is put in a space 11c formed inside the central end sections 11b of the windings 11 in the laminated direction of the windings 11. Since the magnetic fluxes generated from each winding 11 are concentrated through one center core 14, the coupling among the windings 11, 11, and 11 is improved and the inductance and performance of this plane inductance element are improved.

Description

[Detailed Description of the Invention] [Object of the Invention] (Industrial Application Field) The present invention relates to a small and thin planar inductance element suitable as an inductance element for power supplies, inverters, oscillators, etc. The present invention relates to an improved planar inductance element.

(Prior Art) Conventionally, as this type of planar inductance element, there is one in which a plurality of planar windings 1 shown in FIG. For example, it is formed into a circular spiral shape.

In addition, by interposing electrical insulators between the plurality of planar windings 1, 1, etc., it is possible to obtain withstand voltage between these planar windings 1°1 and adjust the electrical characteristics as a planar inductance element. There is something you can do to get a cap.

(Problem to be Solved by the Invention) However, in such a conventional planar inductance element, as shown in FIG. 6, the inside of the spiral central end 1b of the planar winding 1 is just a space, so to speak. Since it is configured as an air-core coil, the inductance is not necessarily high, and when this is incorporated into a transformer, the coupling coefficient between the windings is not necessarily high, so there is a problem that the conversion efficiency is not high.

Therefore, the present invention has been made in consideration of such circumstances, and its purpose is to provide a planar inductance element that can increase inductance and improve performance.

[Structure of the invention]

(Means for Solving the Problems) In order to solve the above problems, the present invention is configured as follows.

In other words, the present invention is characterized in that a magnetic material is disposed in the center space of the spiral of the planar winding in which the conductor is formed in a spiral shape.

(Function) A part of the magnetic flux generated in the planar winding is concentrated and transmitted through the magnetic material at the center of the spiral, resulting in higher inductance and improved performance.

Therefore, when a plurality of these inductance elements are incorporated as a transformer, the coupling coefficient between the windings can be increased and the conversion efficiency can be increased.

(Example) Examples of the present invention will be described below based on FIGS. 1 to 5.

FIG. 2 is a longitudinal cross-sectional view of one embodiment of the present invention. In the figure, the planar inductance element 10 is constructed by laminating, for example, three planar windings 11, 11, 11 concentrically in the vertical direction in the figure. It is held between a pair of upper and lower magnetic materials 12 and 13 made of ferrite, amorphous, or the like.

As shown in FIG. 1, each planar winding 11 has a conductor 11a formed in, for example, a circular spiral shape on almost one plane, and a space 11C inside these spiral central ends 11b has a conductor 11a as shown in FIG. As shown in FIG. 2, a center core 14 formed in a solid cylinder shape from a magnetic material such as ferrite or amorphous is inserted so as to penetrate along the stacking direction (vertical direction in the figure).

For this reason, the magnetic flux generated in each planar winding 11 passes through one center core 14 and concentrates, so that these planar windings 11. 11. 11 is improved, the inductance is increased, and the performance is improved.

FIG. 3 is a longitudinal sectional view of another embodiment of the present invention, and the planar inductance element 20 of this embodiment is constructed by laminating, for example, four of the planar windings 11 shown in FIG. 1 concentrically in the vertical direction. , an electrical insulating film 21 is interposed horizontally at the middle stage in the stacking direction of these planar windings 11, and these four planar windings 11, 11... are laterally partitioned into an upper stage and a lower stage. There is.

Further, the planar inductance element 20 has upper and lower surfaces of the laminate sandwiched between a pair of upper and lower magnetic bodies 22 and 23 with an electrical insulating film 21 interposed therebetween.

A pair of upper and lower center cores 24a, 24b are placed in both spiral central spaces 11c, llc of the upper and lower two stages of planar windings 11, 11... in the stacking direction of the planar windings 11, 11... (in the vertical direction in the figure), each of the upper and lower stages of the plurality of planar windings 11 is inserted so as to penetrate through each of the upper and lower stages.

Therefore, according to this, in addition to being able to increase the inductance by strengthening the coupling between each winding, as in the embodiment described above, by appropriately selecting the thickness of the electrical insulating film 21, the inductance and coupling coefficient can be adjusted. You can set it as appropriate.

FIG. 4 shows a circle for drawing out the lead wires 30 connected to the center ends 11b of both spirals of the upper and lower planar windings 11.11 on the inner surface of the magnetic body 12.13 of the above embodiment. The feature is that arc-shaped recesses 31 and 31 are formed respectively. In addition, in FIG. 4, only the lower magnetic body 13 is illustrated, and the upper magnetic body 12 is omitted.

In other words, the spiral central end 1 of the upper and lower planar windings 11.11
Lead wires 30 respectively connected to 1b, llb...
By inserting the lead wire 30 into each arcuate recess 31, the lead wire 30 can be drawn out of the coil without coming into contact with the upper and lower surfaces of both planar windings 11 and 11, respectively.

Therefore, according to this embodiment, it is possible to prevent the thickness of the planar inductance element from increasing by an amount corresponding to the thickness of the lead wire 30, and it is possible to reduce the thickness of the planar inductance element.

In each of the above-mentioned embodiments, the case where the spiral shape of the planar winding 11 is formed into a circular shape has been described, but the present invention is not limited to this, and may be formed into a rectangular spiral shape, for example.

〔Effect of the invention〕

As explained above, in this invention, since a magnetic material is disposed in the center space of the spiral of the planar winding, a part of the magnetic flux generated in the planar winding is transmitted through the magnetic material in the center of the spiral. It is possible to increase the inductance and improve the performance.

[Brief explanation of the drawing]

FIG. 1 is a schematic plan view showing the main parts of a planar inductance element according to the present invention, FIG. 2 is a longitudinal sectional view of the planar inductance element equipped with a planar coil shown in FIG. 1, and FIG. A vertical sectional view of another embodiment of this invention, FIG.
FIG. 5 is a longitudinal sectional view of a planar inductance element equipped with a magnetic material shown in FIG. 4, and FIG. 6 is a plan view of a conventional planar winding. FIG. DESCRIPTION OF SYMBOLS 10... Planar inductance element, 11... Planar winding, lla... Conductor, llb... Spiral center end,
11c... Spiral central space part, 12.13... Upper and lower pair of magnetic bodies, 14, 24a, 24b... Center core (magnetic body), 30... Lead wire, 31... Arc-shaped recessed part .

Claims (1)

[Claims] A planar inductance element characterized in that a magnetic material is disposed in the center space of a planar winding in which a conductor is formed in a spiral shape.