JPH06251958A - Molded transformer - Google Patents

Abstract

PURPOSE:To simplify the process of production by reducing the number of components needed, to improve productivity, to automate the process of assembling, to cut down the cost of production equipment, and to decrease the irregularity in inductance which is specially important in electric characteristics, and to provide a molded transformer of high safety and high quality at low cost. CONSTITUTION:The molded transformer is constructed in such a manner that one side of both edge faces, the part corresponding to both edge faces of a magnetic core 27 of the encapsulation resin 28 to be formed on the outer circumference of the transformer formed by combining EE-shaped or EI-shaped magnetic core 27, of a magnetic core 27 forms an inclined part 32 which appears to outside. A resin molded transformer is obtained by the molding of encapsulation resin 28.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a mold transformer used in various video equipment, home appliances, audio equipment, industrial equipment, communication equipment and the like.

[0002]

2. Description of the Related Art The structure of a conventional mold transformer will be described with reference to FIGS. FIG. 6 is a sectional view of a conventional mold transformer, and FIG. 7 is a perspective view of the conventional mold transformer. As shown in FIGS. 6 and 7, the conventional mold transformer is provided with a through hole 2 in the center thereof, and a maker terminal 5 for winding wiring, which is integrated with each of lower end flanges 4 at lower ends of the through hole 2.
A coil bobbin 1 in which a user terminal 6 used by a user is wound, a conductor wire 3 such as a copper wire is wound around the coil terminal and wound around a manufacturer terminal 5, and an EE-type or EI-type magnetic core 7 is attached to an adhesive 9 Was used to insert and combine them, and the adhesive was cured in a curing oven, and then molded with the exterior resin 8.

[0003]

In the conventional mold transformer having such a structure, the magnetic core 7 is fixed by the adhesive, and the adhesive may be hardened in the hardening furnace and the cooling process may be performed thereafter. It occupies a large weight and the production process is complicated. Considering the original function of the transformer, the winding process and the magnetic core assembling process are indispensable, but the magnetic core adhering process is intended to temporarily fix the outer resin 8 until it is molded, and the original function of the transformer is required. It is an extra process that is not related to. It is difficult to automate the bonding process, and at present, it is a manual process, which is a big problem. Also, the adhesive 9 forms a thin film on the bonding surface of the magnetic core 7,
A magnetic gap occurs. As a result, there is a problem in terms of electrical characteristics of the transformer that causes a decrease in inductance and variation.

An object of the present invention is to eliminate the above-mentioned conventional defects and to provide a mold transformer capable of incorporating a magnetic core without using an adhesive.

[0005]

In order to solve this problem, the present invention relates to a coil bobbin having a through hole in the center thereof and a winding wound around the coil bobbin, and an EE type or EI type magnetic core incorporated in the coil bobbin. The exterior resin formed on the outer peripheral portion of the coil bobbin is provided with a sloped portion in which one side of both end faces of the magnetic core is exposed to the outside in a portion corresponding to both end faces of the magnetic core.

[0006]

[Function] EE incorporated in the coil bobbin as described above
-Shaped or EI-type magnetic core is formed by forming an inclined portion in which one side of both end faces of the magnetic core is exposed to the outside in a portion corresponding to both end faces of the magnetic core of the external resin. The die taper of the molding die can be brought into contact with the end surface of the magnetic core, and when the molding die is closed, the magnetic core is pressed from above. As a result, the magnetic core tries to move in the direction in which stress can be dispersed, that is, in the center direction of the molding die, and as a result, each moves in the center direction, so that the joining surfaces of the magnetic core are temporarily fixed in a state of being joined together. Since the exterior resin enters the molding die during molding, and the exterior resin covers the entire magnetic core, the resin can completely fix the core.

[0007]

【Example】

(Embodiment 1) A first embodiment of the present invention will be described below with reference to FIGS. 1, 2, 3 and 4. FIG. 1 is a diagram showing the internal structure of a transformer according to the first embodiment of the present invention. FIG. 2 is a perspective view of the transformer according to the first embodiment of the present invention. FIG. 3 is a cross-sectional view showing the mold open state in the first embodiment of the present invention, and FIG. 4 is a cross-sectional view showing the mold closed state in the first embodiment of the present invention.

1, FIG. 2, FIG. 3, and FIG. 4, a through hole 22 is provided in the center, and a maker terminal 25 for winding wiring, which is integrated with each of lower end flanges 24 at the lower ends of both ends, and a user used by the user. In the coil bobbin 21 in which the terminal 26 is implanted,
The outer circumference of a transformer having a closed magnetic circuit formed by winding a conductor wire 23 such as a copper wire and inserting and combining an EE-type or EI-type magnetic core 27 into the coil portion wound around the manufacturer terminal 25 without using an adhesive. The magnetic core 2 of the exterior resin 28 formed in the portion
7 is a mold transformer having a structure in which inclined portions 32 in which one side of both end surfaces 29 of the magnetic core 27 are exposed to the outside are formed in portions corresponding to both end surfaces of 7.

With this configuration, one side of the magnetic core end face 29 is exposed to the outside in a portion of the exterior resin 28 formed on the outer peripheral portion of the EE type or EI type magnetic core 27 incorporated in the coil bobbin 21 corresponding to both end faces of the magnetic core 27. By forming the exposed inclined portion 32, the molding die 33 is formed at the time of molding the exterior resin 28.
The die taper portion 34 and the both end surfaces 29 of the magnetic core 27 can be brought into contact with each other, and when the molding die 33 is closed, the magnetic core 27 is pressed from above. As a result, the magnetic core 27 tends to move in the direction in which the stress can be dispersed, that is, in the central direction of the through hole 22. As a result, each of them moves toward the center, so that the joint surfaces of the magnetic core 27 can be temporarily fixed in a state where they are temporarily joined. After that, the exterior resin 28 enters the molding die 33 during molding, and the magnetic core 27 can be completely fixed by the exterior resin 28 because the exterior resin 28 covers the entire magnetic core 27.

(Second Embodiment) A second embodiment of the present invention will be described below with reference to FIG. FIG. 3 is a perspective view of a mold transformer showing a second embodiment of the present invention.

In the mold transformer described in the first embodiment, the magnetic core 27 is provided at the portions corresponding to both end faces of the magnetic core 27.
And the non-exposed portion 3 in which one side of both end surfaces 29 of the
The molded transformer having the structure 1 is provided.

With this structure, one side of both end surfaces 29 of the magnetic core 27 is formed in a portion of the outer resin 28 formed on the outer peripheral portion of the EE type or EI type magnetic core 27 incorporated in the coil bobbin 21 corresponding to both end surfaces of the magnetic core 27. By forming the inclined portion 32 that is exposed to the outside and the non-exposed portion 31, the die taper portion 34 of the molding die 33 and the magnetic core end surface 29 are brought into contact with each other when the exterior resin 28 is molded as described above. As a result, there is an effect that the magnetic core 27 can be pressed from above, and since the molding die 33 and the magnetic core 27 have a non-contact portion, the exterior resin 28 flows through the non-exposed portion 31, It is possible to easily fill the lower surface and the top surface side with the exterior resin 28,
As a result, it is possible to mold without impeding the resin fluidity.

[0013]

As described above, the present invention is of the EE type or the E type.
An I-shaped magnetic core is inserted and combined without using an adhesive, and one side of both end faces of the magnetic core is external to a portion of the outer resin formed on the outer peripheral portion of the transformer having the closed magnetic circuit, which corresponds to both end faces of the magnetic core. It is possible to construct a complete resin mold transformer by forming a sloped part that appears on the surface and molding it with the exterior resin. As a result, the number of parts is reduced, which simplifies the production process and improves productivity. Improvement and automation of assembly process It is possible to reduce investment in production equipment and realize and provide a low cost, high precision, high safety and high quality mold transformer made of complete resin.

[Brief description of drawings]

FIG. 1 is a sectional view of a mold transformer according to a first embodiment of the present invention.

FIG. 2 is a perspective view of a mold transformer according to the first embodiment of the present invention.

FIG. 3 is a sectional view showing a mold open state in the first embodiment of the present invention.

FIG. 4 is a sectional view showing a closed state of a mold according to the first embodiment of the present invention.

FIG. 5 is a perspective view of a mold transformer according to a second embodiment of the present invention.

FIG. 6 is a cross-sectional view showing the configuration of a conventional mold transformer.

FIG. 7 is a perspective view showing a configuration of a conventional mold transformer.

[Explanation of symbols]

 21 coil bobbin 22 through hole 23 conductor wire 24 lower end collar 25 manufacturer terminal 26 user terminal 27 magnetic core 28 exterior resin 29 both ends of magnetic core 31 non-exposed portion 32 inclined portion 33 molding die 34 die taper portion

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Toyo Tamura 1006 Kadoma, Kadoma City, Osaka Prefecture Matsushita Electric Industrial Co., Ltd.

Claims (2)

[Claims] 1. A coil bobbin having a through hole in the center and a winding wound thereon, an EE type or EI type magnetic core incorporated in the coil bobbin, and an exterior resin formed on the outer peripheral portion of the coil bobbin incorporating the magnetic core. A molded transformer having a slanted portion, in which one side of both end faces of the magnetic core is exposed, in a portion of the exterior resin corresponding to the both end faces of the magnetic core. 2. The mold transformer according to claim 1, wherein the portion corresponding to both end faces of the magnetic core is provided with an inclined portion and a non-exposed portion where one side of the both end faces of the magnetic core is exposed.