JP4844438B2 - Line filter - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a line filter with reliability to a mechanical impact improved by providing a structure for stabilizing a fixing and holding of a core to a bobbin. <P>SOLUTION: The line filter of this invention comprises: a first magnetic core 15; a bobbin 17 having a through-hole 14 with the first magnetic core 15 inserted; a second magnetic core 19 for covering a part of the first magnetic core 15, and a winding wound around the outer circumference of the bobbin 17. The bobbin 17 is formed with identically shaped two separated bobbins 17a, 17b separated in an axis direction of the through-hole 14 assembled. The second magnetic core 19 is formed by two separated magnetic cores 19a, 19b. The separated magnetic cores 19a, 19b are arranged in a groove for the magnetic core provided at the through-hole 14 side of the bobbin, and stoppers 20a, 20b for pressurizing the second magnetic core 19 are provided to one end part of the groove for the magnetic core. <P>COPYRIGHT: (C)2008,JPO&amp;INPIT

Description

  The present invention relates to a line filter used in various electronic devices.

  As shown in FIG. 9, the conventional line filter has a configuration in which a first winding 2 and a second winding 3 are wound around a bobbin 1, and a magnetic leg 6 of a magnetic core 5 is inserted into a through hole 4. It has become. The bobbin 1 is formed by combining two divided bobbins 7 as shown in FIG. 10 for convenience of production. Further, the split magnetic core 8 is disposed on the surface of the split bobbin 7 where the through hole 4 is formed in order to secure a magnetic path for adding a function of suppressing not only the common mode noise but also the normal mode noise.

  The split magnetic core 8 was fixed and held by a claw portion 10 provided at the tip of the holding portion 9 of the split bobbin 7 as shown in the sectional view of FIG.

For example, Patent Document 1 is known as prior art document information relating to the invention of this application.
JP 2004-153216 A

  In the conventional line filter, the split magnetic core 8 is fixedly held by the thin claw portion 10 and the elastic force of the holding portion 9 and the claw portion 10 is used as a force necessary for the fixing and holding. For each of these parts, the dimensional accuracy of thickness and length is required at a high level.

  Therefore, when a small deviation in the thickness or length of the holding portion 9 or the claw portion 10 occurs, the fixed holding state of the divided magnetic core 8 tends to become unstable, and as a result, the divided magnetic core 8 is insufficiently fixed. Because of this, there is a possibility of generating a roaring sound during operation.

  SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to suppress the generation of a roaring sound.

In order to achieve this object, a first magnetic core, a bobbin having a through-hole into which the first magnetic core is inserted, a second magnetic core covering a part of the first magnetic core, and an outer periphery of the bobbin The bobbin is formed by combining two divided bobbins having the same shape divided in the axial direction of the through hole, the second magnetic core is formed by two divided magnetic cores, and the divided The magnetic core is disposed in a magnetic core groove provided on the through hole side of the divided bobbin, and a stopper for pressing the divided magnetic core is provided at one end of the end portions of the magnetic core groove in both the divided bobbins. One of the divided magnetic cores is pressed by one side of the stopper, and the other divided magnetic core is pressed by a convex portion provided at the tip of the other side of the stopper, so that the convex portion of one of the divided bobbins and the other divided portion In bobbin Is obtained is characterized in that fitted to an end portion of the stopper is not formed side of the magnetic core groove.

According to the present invention, by providing the bobbin with a pressing portion that stabilizes the fixed holding of the divided magnetic cores , both the divided magnetic cores and both the divided bobbins are pressed against each other to be fixed, thereby suppressing the generation of a roaring sound. .

  Hereinafter, a line filter according to an embodiment of the present invention will be described with reference to the drawings. As shown in FIG. 1, the first winding 12 and the second winding 13 are wound around the bobbin 11, and the magnetic leg 16 of the first magnetic core 15 is inserted into the through hole 14. The bobbin 11 is formed by combining two divided bobbins 17 as shown in FIG. Further, in order to secure a magnetic path for adding a function of suppressing not only common mode noise but also normal mode noise, a magnetic core groove 18 is provided in a surface corresponding to the through hole 14 of the bobbin 17. The second magnetic core 19 is arranged to form a closed magnetic circuit for suppressing normal mode noise.

  As shown in the sectional view of FIG. 3, the first divided magnetic core 19 a and the second divided magnetic core 19 b divided in the axial direction of the through hole 14 are combined to cover a part of the magnetic leg 16.

  Here, the stopper 20a provided on the first divided bobbin 17a presses the second divided magnetic core 19b arranged on the second divided bobbin 17b, and at the same time, the stopper 20b provided on the second divided bobbin 17b is applied to the first divided bobbin 17b. The first divided magnetic core 19a disposed on the bobbin 17a is pressed.

  The operation and effect of the inductor element according to the present embodiment having the above configuration will be described below.

  As described above, the stopper 20a of the first divided bobbin 17a presses the second divided magnetic core 19b disposed on the second divided bobbin 17b, and at the same time, the stopper 20b of the second divided bobbin 17b serves as the first divided bobbin 17a. It is set as the structure which presses the 1st division | segmentation magnetic core 19a arrange | positioned. The first divided bobbin 17a and the second divided bobbin 17b have the same shape, and at the same time, the first divided magnetic core 19a and the second divided magnetic core 19b have the same shape.

  As a result, the first divided bobbin 17a presses and fixes the second divided magnetic core 19b while holding the first divided magnetic core 19a, and the second divided bobbin 17b holds the second divided magnetic core 19b while holding the first divided magnetic core 19b. By pressing and fixing the divided magnetic cores 19a, the two magnetic cores 19a are pressed and fixed to each other, thereby maintaining the positional relationship between them stably.

  Therefore, the positional relationship between the respective winding portions (not shown), the magnetic leg 16 and the first magnetic core 15 is less likely to change, and therefore the characteristics change or deteriorate even when subjected to a mechanical shock or the like. It can be made difficult.

  Further, since the stopper 20a of the first divided bobbin 17a and the stopper 20b of the second divided bobbin 17b have very simple shapes, dimensional accuracy is required when the first divided bobbin 17a and the second divided bobbin 17b are formed. Since resin burrs and the like are less likely to occur, the above-described action of pressing and fixing to each other can provide the action of stably maintaining the positional relationship between the two with high accuracy.

  If there is one stopper for each divided bobbin, such as the stopper 20a of the first divided bobbin 17a and the stopper 20b of the second divided bobbin 17b, it has a function of pressing and fixing.

  As a form for further enhancing the above effect, as shown in FIG. 4, the stopper 20a of the first divided bobbin 17a is provided with a convex portion 21a, which corresponds to the end of the magnetic core groove 18 shown in FIG. The concave portion 22b shown in FIG. 4 is provided in the second divided bobbin 17b or the second divided magnetic core 19b.

  At the same time, a convex portion 21b is provided on the stopper 20b of the second divided bobbin 17b, and a corresponding concave portion 22a is provided on the second divided bobbin 17a or the first divided magnetic core 19a.

  As a result, the first divided bobbin 17a and the second divided bobbin 17b can be fitted to each other as shown in FIG. 5 in addition to the aforementioned fixed fixing by the divided bobbins 17a and 17b. The stability of fixation can be increased.

  The most appropriate dimensions here are the points A1, A2, B1, B2, C1, C2, C3, and C4, ie, the first divided bobbin 17a. In the first and second divided bobbins 17b, there are preferably three pressing points.

  As a result, the first divided bobbin 17a presses and fixes the second divided magnetic core 19b while holding the first divided magnetic core 19a, and the second divided bobbin 17b holds the second divided magnetic core 19b while holding the first divided magnetic core 19b. The divided magnetic core 19a is pressed and fixed, and the effect of fixing by itself and fixing by each other is most easily exhibited.

  That is, the force pressed by the stoppers 20a and 20b functions as a force for fixing the first and second divided magnetic cores 19a and 19b through the opposing second and first divided magnetic cores 19b and 19a, and is stable. Maintain the relationship.

  Further, even when the contact between the points A1, A2, C1, C2, C3, and C4 is insufficient, the magnetic core groove 18 is inserted into the through hole 14 side as shown in FIGS. A rib 23 that increases as it goes to the outside of the bobbin 17 may be provided to have a function of substituting or assisting fixing. However, it is necessary to press at the point B1 by the stopper 20a and the point B2 by the stopper 20b.

  Here, the stoppers 20a and 20b shown in FIG. 5 can be divided into the bobbins 17a and 17b of the stoppers 20a and 20b if the dimensional accuracy of the dimension W in the direction of the second and first divided magnetic cores 19b and 19a facing each other is ensured. The positional deviation of the second and first divided magnetic cores 19b and 19a is not likely to be a big problem.

  For example, FIG. 8A shows the positional relationship between the magnetic leg 16 and the first and second divided magnetic cores 19a and 19b when the stoppers 20a and 20b are in the standard positions, and the stoppers 20a and 20b in FIG. FIG. 8B shows the positional relationship between the first magnetic core 15 and the magnetic leg 16 and the first and second divided magnetic cores 19a and 19b when protruding in the direction of the opposing second and first divided magnetic cores 19b and 19a. ) Respectively.

  Here, if the divided bobbins (not shown) have substantially the same dimensions in FIGS. 8 (a) and 8 (b), the stoppers 20a and 20b shown in FIG. If the dimensions of the stoppers 20a and 20b do not change with W even if they protrude too much, the first and second divided magnetic cores 19a and 19b in either case of FIG. 8 (a) and FIG. 8 (b) No change occurs in the opposing distance W of 19b. And the relative position with respect to the magnetic leg 16 of the 1st, 2nd division | segmentation magnetic cores 19a and 19b will hardly change only by rotating the circumference | surroundings of the magnetic leg 16. FIG. In particular, by making the cross-sectional shape of the magnetic leg 16 polygonal, it is possible to further reduce the change in the positional relationship due to this rotation, and the most desirable shape is a circle.

  From the above, by maintaining the dimensional accuracy of W, by fixing the first and second divided magnetic cores 19a and 19b, it is difficult to cause deterioration of characteristics even under mechanical shock, and Product characteristics can be made small. In other words, the fixed state of the first and second divided magnetic cores 19a and 19b can be adjusted by adjusting the dimension of W.

  In other words, the product characteristics are stabilized by managing the dimensions of a simple shape, such as the stoppers 20a and 20b shown in FIG. It is possible.

  The line filter of the present invention has an effect of suppressing deterioration of magnetic and electrical characteristics caused by mechanical shock, and is useful in various electronic circuits using the line filter.

The perspective view which shows one Embodiment of the line filter of this invention The perspective view of the bobbin in one Embodiment of the line filter of this invention Sectional drawing which shows one Embodiment of the line filter of this invention Sectional drawing of the bobbin in one Embodiment of the line filter of this invention Sectional drawing which shows one Embodiment of the line filter of this invention The front view of the bobbin in one Embodiment of the line filter of this invention Sectional drawing of the bobbin in one Embodiment of the line filter of this invention (A) Sectional drawing which shows one Embodiment of the line filter of this invention, (b) Sectional drawing which shows one Embodiment of the line filter of this invention A perspective view showing a conventional line filter A perspective view of a bobbin in a conventional line filter Sectional view showing a conventional line filter

Explanation of symbols

14 Through-hole 15 First magnetic core 17 Bobbin 19 Second magnetic core 19a, 19b Split magnetic core 20a, 20b Stopper

Claims (1)

A first magnetic core;
A bobbin having a through-hole into which the first magnetic core is inserted;
A second magnetic core covering a portion of the first magnetic core;
A winding for winding the outer periphery of the bobbin;
The bobbin is formed by combining two divided bobbins having the same shape divided in the axial direction of the through hole,
The second magnetic core is formed by two split magnetic cores;
The split magnetic core is disposed in a magnetic core groove provided on the through hole side of the split bobbin,
A stopper that presses the divided magnetic core is provided at one end of the ends of the groove for the magnetic core in both the divided bobbins,
One of the divided magnetic cores is pressed by one side of the stopper, and the other divided magnetic core is pressed by a convex portion provided at the tip of the other side of the stopper,
A line filter in which a convex portion of one of the divided bobbins and an end portion on the stopper non-formation side of the magnetic core groove in the other divided bobbin are fitted.

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