JPH0557823U - Magnetic core - Google Patents

Abstract

(57) [Abstract] [Purpose] To provide a magnetic core having a shape in which variation in saturation magnetic characteristics is unlikely to be large even if the magnetic core is slightly deformed or assembled. [Structure] In a U-shaped or E-shaped magnetic core, the shape of the joining surface of two magnetic core pieces to be combined is one of which is a magnetic leg having a width capable of obtaining a prescribed cross-sectional area, and the other one is of The magnetic core has a structure in which the centers of the magnetic legs coincide with each other, and the width of the magnetic legs is designed to be wider than that of the magnetic core pieces, and the magnetic core pieces are combined. That is, a magnetic circuit is constructed by facing the ends of the magnetic legs of the two magnetic core pieces, and the winding 4 is applied to this magnetic circuit.
In a magnetic core that constitutes a wire ring or the like, a magnetic leg having a magnetic core piece (2) having a predetermined area for the bonding surface of the magnetic leg, and a magnetic leg having a bonding surface larger than the size of the bonding surface of the magnetic leg of the magnetic core piece. The magnetic core is characterized by a structure in which the magnetic core piece 1 having a wider width is combined.

Description

[Detailed description of the device]

[0001]

[Industrial application]

 The present invention relates to a magnetic core used for an electronic component such as a transformer or a coil, and relates to a structure of a magnetic core that constitutes a magnetic path by facing two U-shaped and E-shaped magnetic core pieces.

[0002]

[Prior Art]

 Conventionally, a split type magnetic core, which is a sintered type or a thermosetting type made of ferrite or metal powder, and which forms a magnetic path by facing two magnetic core pieces, has the same E-shaped or U-shaped metal core. The magnetic leg of a magnetic core piece of the same shape processed by the mold was inserted into the wound bobbin, the joint surfaces were faced and fixed, and the transformer and coil were completed. One of the characteristics required for these wire rings is the saturation magnetic characteristic, and the value of the maximum saturation magnetic flux of the magnetic core is important. The value of this maximum saturation magnetic flux is related to the maximum saturation magnetic flux density of the magnetic core material and the cross-sectional area of the magnetic path of the magnetic core. Therefore, this variation in the saturation magnetic characteristics is related to the variation in the magnetic core material and the joining area of the joining surface of the magnetic core piece. Depends on. As shown in FIG. 2, conventionally, when assembling two E-shaped magnetic core pieces 2 of the same shape, the central magnetic leg 17 and the outer magnetic leg 16 are faced to each other, and a bobbin having a winding 4 is formed. Although the central magnetic leg 17 is inserted and assembled, when the magnetic core piece is ideally free from deformation or variation as shown in FIG. 2, it works with the designed cross-sectional area of the magnetic circuit. However, in reality, as shown in FIG. 3, when one of the magnetic core pieces to be combined is spread and deformed like the deformed magnetic core piece 3, the assembly is performed carefully and the central magnetic leg 17 is accurately positioned. Even if it is adjusted, the magnetic legs 16 on the upper and lower sides are displaced, and the junction area is narrowed like the dimensions E9 and F10. In general, the cross-sectional area of the central magnetic leg is designed to be twice the cross-sectional area of the outer magnetic leg in order to make the cross-sectional area in the magnetic path uniform. Therefore, as the dimension of the joint surface of the magnetic legs on both outer sides becomes narrower, a portion with a small saturated magnetic flux value is created in the magnetic path, which may cause variations in saturation magnetic characteristics or break down of the minimum standard value. Become. That is, the variation in the bonding area due to the deformation of the legs of the magnetic cores to be combined has an effect on the variation in the saturation magnetic characteristics because the ferrite magnetic core and the powder magnetic core, which are shaped by sintering or thermosetting, have large deformation. Is a big problem. Even if the magnetic core is not deformed, if the joining positions are displaced during assembly as shown in Fig. 4, the effective joining area becomes smaller in the central magnetic leg 17 and the outer magnetic leg 16, respectively, and the minimum value is specified. There is a problem that the value is divided or the variation is increased.

[0003]

[Problems to be solved by the device]

 The problem to be solved by the present invention is to solve the above-mentioned problems, and the cross-sectional area in the magnetic circuit does not become smaller than the design value even if the magnetic core is slightly deformed or the assembly is misaligned. Is to provide a magnetic core having a shape that does not easily become large.

[0004]

[Means for Solving the Problems]

 SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention provides a joint surface shape of two magnetic core pieces to be combined in a U-shaped or E-shaped sintered core or the like, one of which has a prescribed cross-sectional area. The other is a magnetic core having a structure in which the center of the magnetic core is aligned with the center of the magnetic core and the width of the magnetic core is designed to be wider than that of the magnetic core and the magnetic core is combined. To provide.

That is, according to the present invention, a magnetic circuit is constructed by facing the tips of the magnetic legs of two magnetic core pieces, respectively, and windings are applied to the magnetic circuit to form a coil. Characterized by a structure in which a magnetic core piece having a contact area of a magnetic leg having a predetermined area and a magnetic core piece having a magnetic leg of a joint surface larger than the size of the joint surface of the magnetic leg of the magnetic core piece are combined. It is a magnetic core.

[0006]

[Action]

 As shown in FIG. 5, the area of the magnetic leg of the joint of the magnetic core pieces to be combined is larger than the magnetic core piece 2 of the design value according to the standard used. Since the magnetic circuit is assembled with, even if the position of the joint part of the magnetic leg changes slightly due to variations in the assembly of the core or deformation of the core due to sintering, etc. The joint surface of the magnetic leg of the magnetic core piece of is contained, and the cross-sectional area of the magnetic path at the joint does not become smaller than the design value.

[0007]

【Example】

 Hereinafter, embodiments of the present invention will be described with reference to the drawings. Examples of the EE type magnetic core of the ferrite produced by the sintering method will be described below. FIG. 1 is a front view of a magnetic core according to an embodiment of the present invention, showing a state in which magnetic core pieces of a regular shape are combined, and FIG. 5 is a front view showing an assembled state when the magnetic core of the present invention is deformed. It is a figure.

As shown in FIG. 1, the sintered dimension is about 30 mm × 13 mm, the thickness is 10 mm, the width of the central magnetic leg (dimension A5) is 10 mm, and the outer magnetic leg (dimension C7) is The E-shaped ferrite core piece 2 designed and manufactured in a standard size with a width of 5 mm, the center position of the magnetic legs facing each other, the length of the legs, and the cross-sectional area of the back are designed according to the standard dimensions described above. A magnetic core piece 1 was prepared in which the width of each leg was widened in both directions from the center position by 10% and the width of the magnetic leg was widened. That is, since the thickness direction is polished, the deviation due to the assembly can be almost ignored. Therefore, only the width direction of each leg is widened, the width of the central magnetic leg 17 is 11 mm, and the width of the outer magnetic leg 16 is set. A ferrite magnetic core piece having a size of 5.5 mm was prepared. The above-mentioned two kinds of magnetic core pieces were inserted into bobbins of wound coils by a jig that was installed with the center positions of the backs of the respective magnetic core pieces aligned, and the magnetic core pieces were fixed to assemble the coil. Comparing the saturation magnetic characteristics of the coil assembled with the magnetic core of this example and the coil assembled with the magnetic core pieces designed and manufactured according to the standard dimension as in the conventional method, it was found that the conventional method has a variation in the standard. There was about 5% that was out of the range, but in this example, it could be 1% or less. If the joint surface is made larger than the standard size, it will be uneconomical if it is too large. Therefore, it is determined by the variation of the magnetic core legs determined by the manufacturing conditions of each core.

[0009]

[Effect of the device]

 As described above, according to the present invention, there is provided a magnetic core capable of constructing a magnetic circuit without dividing the minimum cross-sectional area in the magnetic path even if the magnetic core is misaligned or the core is deformed. Therefore, it is possible to supply electronic parts such as transformers and coils with little variation in magnetic saturation characteristics.

[Brief description of drawings]

FIG. 1 is a front view of a magnetic core according to an embodiment of the present invention, showing a state in which regular shaped magnetic core pieces are combined.

FIG. 2 is a conventional magnetic core, in which two magnetic core pieces each having a regular shape are
The front view of the state where it was correctly combined.

FIG. 3 is a front view illustrating a state in which a conventional magnetic core is deformed to cause an assembly deviation.

FIG. 4 is a front view of a conventional magnetic core, in which magnetic core pieces having a regular shape are combined and the assembly is misaligned.

FIG. 5 is a front view of a magnetic core assembled with the magnetic core of the present invention deformed.

[Explanation of symbols]

 1 Magnetic core piece with widened width of magnetic leg 2 Magnetic core piece 3 Deformed magnetic core piece 4 Winding 5 Dimension A 6 Dimension B 7 Dimension C 8 Dimension D 9 Dimension E 10 Dimension F 11 Dimension G 12 Dimension H 13 Dimension I 14 Dimension J 15 Dimensions K 16 Outer magnetic leg 17 Central magnetic leg

Claims (1)

[Scope of utility model registration request] 1. A magnetic circuit comprising two magnetic core pieces with the tips of the magnetic legs facing each other to form a magnetic circuit, and winding is applied to the magnetic circuit to form a loop or the like. And a magnetic core piece having an area of a predetermined area and a magnetic core piece having a magnetic leg of a joint surface larger than the size of the joint surface of the magnetic leg of the magnetic core piece.