JP2009246186A - Transformer - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a transformer capable of improving an assembling operation efficiency and stably controlling an inductance value. <P>SOLUTION: The transformer includes a first magnetic material core (1) and a second magnetic material core (2) disposed opposite each other to form a closed magnetic path, wherein a dot pattern of nonmagnetic resin consisting of at least three or more dots (10) is formed by coating on an opposite surface (11) of at least one of the first magnetic material core and second magnetic material core, and the dot pattern is brought into contact with the other opposite surface (21a, 22a, 23a). Preferably, an epoxy-based adhesive is used as the nonmagnetic resin and the dot pattern is formed by ink jetting. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention particularly relates to an assembly structure of a first magnetic core and a second magnetic core constituting an inverter transformer for operating a cold cathode tube.

  For example, as shown in FIG. 3, the inverter transformer includes a winding (not shown) wound around a central magnetic leg 22 located at the center of the three magnetic legs 21, 22, and 23 of the E-type ferrite core 2. In addition, the rectangular columnar I-type ferrite core 1 is placed on the tip flat surfaces 21a, 22a, and 23a of the magnetic legs 21, 22, and 23 with the insulating sheet 3 interposed therebetween. The ferrite core 2 and the I-type ferrite core 1 are disposed to face each other (see FIG. 3). Further, if necessary, the insulating sheet 3 is fixed to the E-type ferrite core 2 and the I-type ferrite core 1 with an adhesive or the like, and the outer periphery of the E-type ferrite core 2 and the I-type ferrite core 1 is fixed with a tape or the like. Thus, a closed magnetic path is formed by the E-type ferrite core 2 and the I-type ferrite core 1 and assembled. In the inverter transformer assembled in this way, magnetic saturation is suppressed by the insulating sheet 3 between the E-type ferrite core 2 and the I-type ferrite core 1.

  However, during the assembly operation, the insulating sheet 3 is placed on the tip flat surfaces 21a, 22a, 23a of the magnetic legs 21, 22, 23, and in the process of placing the I-type ferrite core 1 thereon, a little However, when an external force is applied, a positional shift occurs, and in some cases, there is a possibility that the magnetic legs 21, 22, 23 may be detached from the tip flat surfaces 21a, 22a, 23a. For this reason, the assembly of the E-type ferrite core 2 and the I-type ferrite core 1 requires a careful work and has a drawback of poor work efficiency.

  Furthermore, when an adhesive is applied to the front and back surfaces of the insulating sheet 3 and the insulating sheet 3 is fixed to the E-type ferrite core 2 or the I-type ferrite core 1, the thickness varies due to drying after the adhesive is applied. There is a risk that the inductance value fluctuates.

Japanese Utility Model Publication No. 6-31124 JP 2006-100615 A

  The present invention has been made in view of such circumstances, and an object of the present invention is to provide a transformer that can increase the assembly work efficiency and can also stably manage the inductance value.

  In other words, the transformer according to the first aspect of the present invention includes a first magnetic core and a second magnetic core that are disposed opposite to each other to form a closed magnetic path, and the first magnetic core and the above-described magnetic core A non-magnetic resin dot pattern consisting of at least three dots is applied and formed on one of the opposing surfaces of the second magnetic core, and the dot pattern is in contact with the other opposing surface. It is characterized by.

  According to a second aspect of the present invention, in the transformer according to the first aspect, the dot pattern is formed by inkjet.

  According to a third aspect of the present invention, in the transformer according to the first or second aspect, the nonmagnetic resin is an epoxy adhesive.

  According to invention of Claims 1-3, the dot pattern of the nonmagnetic resin which consists of a dot of at least 3 or more is apply | coated to any one opposing surface of a 1st magnetic body core and a 2nd magnetic body core. By forming and bringing the dot pattern into contact with the other opposing surface, a clearance can be provided between the first magnetic core and the second magnetic core. For this reason, the clearance can be ensured by a minimum amount of nonmagnetic resin, magnetic saturation can be suppressed by the clearance, and further, unlike the case of securing the clearance via an insulating sheet, assembly is possible. It can be assembled efficiently without any risk of misalignment during work.

  In addition to this, the adhesive can be applied between the dots, the size of the clearance can be changed due to the thickness variation due to drying after the adhesive is applied, and the inductance value can be prevented from fluctuating, As a result, the inductance value can be safely managed.

  In particular, according to the second aspect of the present invention, by forming a dot pattern on one of the opposing surfaces of the first magnetic core and the second magnetic core by inkjet, the film thickness of each dot can be reduced. The clearance can be stably secured with the minimum necessary coating amount by adjusting the coating amount.

  Furthermore, as in the invention described in claim 3, by using an epoxy adhesive as the nonmagnetic resin, the adhesion of the dot pattern to the one opposing surface can be improved, and the dot pattern is cured and dried. Later fluctuations in film thickness can be suppressed, and the clearance can be secured more stably.

The transformer according to the present invention will be described below.
The transformer of this embodiment has an I-type ferrite core (first magnetic core) 1 and an E-type ferrite core (second magnetic core) 2 as shown in FIGS. The I-type ferrite core 1 has a prismatic shape.

On the other hand, the E-type ferrite core 2 includes a prismatic back magnetic leg 20 and three prismatic magnetic legs 21, 22 arranged vertically from the back magnetic leg 20 toward the I-type ferrite core 1. 23 is integrally provided and has the same width w as the facing surface 11 of the I-type ferrite core 1.
Furthermore, each magnetic leg 21, 22, 23 has a rectangular tip plane (opposing surface) 21 a, 22 a, 23 a that faces the I-type ferrite core 1, and the three magnetic legs 21, 22, The central magnetic leg 22 located at the center of 23 is wound as a winding shaft.

  On the other hand, on the facing surface 11 of the I-type ferrite core 1, an epoxy adhesive dot pattern composed of at least three dots 10 is applied and formed on portions corresponding to the tip flat surfaces 21 a, 22 a, and 23 a. Yes. In particular, a dot pattern consisting of five dots 10 each having dots 10 at positions corresponding to the center of the tip plane 22a and each corner is applied to the portion corresponding to the tip plane 22a of the central magnetic leg 22. ing.

  Each dot 10 is a thermosetting epoxy adhesive applied and formed by ink jet, and is cured and dried by heating at 100 ° C. to 120 ° C., and fluctuations in film thickness after curing and drying are suppressed. Adhesiveness to the facing surface 11 of the ferrite core 1 is enhanced.

  The I-type ferrite core 1 is placed so that the dot pattern is in contact with the tip flat surfaces 21a, 22a, and 23a of the E-type ferrite core 2, respectively. Further, if necessary, an adhesive is applied to the outer periphery of each of the three or more dots 10 constituting each dot pattern, and the outer periphery of each of the E-type ferrite core 2 and the I-type ferrite core 1 is taped or the like. By being fixed, a closed magnetic circuit is formed by the E-type ferrite core 2 and the I-type ferrite core 1, and an inverter transformer for lighting a cold cathode tube is assembled.

  According to the transformer of the above-described embodiment, the epoxy-based adhesive composed of at least three dots or more by ink-jetting on the portions corresponding to the respective tip flat surfaces 21a, 22a, 23a in the facing surface 11 of the I-type ferrite core 1 By applying and forming a dot pattern, the I-type ferrite core 1 is supported on the tip flat surfaces 21a, 22a, and 23a of the magnetic legs 21, 22, and 23 of the E-type ferrite core 2, so that the I-type ferrite core 1 A clearance can be provided between the E-type ferrite core 2 and the E-type ferrite core 2.

  Furthermore, each dot 10 can improve the adhesiveness with respect to the E-type ferrite core 2 by using the above-mentioned epoxy-based adhesive, and can suppress fluctuations in film thickness after curing and drying, so that the clearance can be stably maintained. Can be secured.

  In addition to this, an adhesive can be applied between the dots 10, and it is possible to prevent the inductance value from fluctuating due to a change in the size of the clearance due to thickness variation due to drying after the adhesive is applied. As a result, the inductance value can be safely managed.

  Therefore, unlike the case where the clearance is ensured through the insulating sheet, it is possible to assemble efficiently without fear of positional deviation during the assembly operation, and furthermore, the film thickness of each dot 10 is adjusted according to the coating amount. Thus, the clearance can be stably secured with the minimum required coating amount.

  In addition, this invention is not limited to the above-mentioned embodiment at all, For example, using 1st magnetic body cores other than I type ferrite core 1 and E type ferrite core 2, and 2nd magnetic body core are used. Also good. The dot pattern is not limited to inkjet, and may be formed by printing such as intaglio printing.

It is principal part explanatory drawing of the trans | transformer of this embodiment, Comprising: It is a perspective view of the assembly structure of the 1st magnetic body core and the 2nd magnetic body core. FIG. 2 is an exploded explanatory view of FIG. 1. It is principal part explanatory drawing of the conventional trans | transformer, Comprising: It is decomposition | disassembly explanatory drawing of a 1st magnetic body core and a 2nd magnetic body core.

Explanation of symbols

1 I-type ferrite core (first magnetic core)
2 E-type ferrite core (second magnetic core)
10 dots 11 opposing surface of the first magnetic core to the second magnetic core 20 back magnetic legs 21, 22, 23 magnetic legs 21a, 22a, 23a tip flat surface (opposing surface)
w width

Claims (3)

A first magnetic core and a second magnetic core that are disposed opposite to form a closed magnetic path;
A dot pattern of a non-magnetic resin composed of at least three dots or more is applied and formed on the opposing surface of either the first magnetic core or the second magnetic core, and the dot pattern is applied to the other of the first magnetic core and the second magnetic core. A transformer characterized by being in contact with an opposing surface.   The transformer according to claim 1, wherein the dot pattern is formed by inkjet.   The transformer according to claim 1, wherein the nonmagnetic resin is an epoxy adhesive.

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