JP2000216032A - Narrow-width transformer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the height of a narrow-width, low-height transformer independently of the thickness of bases which support its cores. SOLUTION: This transformer comprises narrow-width and elongated cores 1 and 2 for forming a closed magnetic circuit, a primary winding 3 and a secondary winding 4 which are concentrically wound around an intermediate leg portion formed on at least one of the cores 1 and 2, and a pair of bases 7 each having terminals 8 for connecting terminals of a corresponding one of the windings 3 and 4. The bases 7 are attached to both ends of a corresponding one of the cores 1 and 2 in a manner opposed to each other along the length of the core with their bottom surfaces being flush with the bottom surface of the core.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a transformer used for a switching power supply or the like.

[0002]

2. Description of the Related Art In recent years, as electronic devices have been reduced in size and weight, transformers and coils used in these devices have also been required to be reduced in size and height. In order to increase the mounting density of such electronic components, it is required to reduce the width of these electronic components.

[0003]

A first feature of the present invention is as follows.
A narrow and long strip-shaped core forming a closed magnetic circuit, a primary winding and a secondary winding concentrically mounted on a middle leg formed on at least one of the cores, and terminals of the respective windings are connected. And two bases provided with terminals for mounting the base. Each base is mounted to face both ends in the longitudinal direction of a core forming a closed magnetic circuit so that the base bottom surface and the core bottom surface are flush with each other. That is. A second feature of the present invention is that a primary winding or a secondary winding is provided on at least one outer peripheral surface of the two bases.
That is, a guide plate having a guide groove for guiding the terminal of the next winding to the terminal is attached. A third feature of the present invention is that the guide plate is arranged along the longitudinal direction of the core. A fourth feature of the present invention is that a concave portion is formed on the bottom surface at both ends in the longitudinal direction of the core forming the closed magnetic path, and the base is mounted on the concave portion so that the base bottom surface and the core bottom surface are flush with each other. That is to say. Further, a fifth feature of the present invention is that at least one of the cores forming the closed magnetic path is provided with a step portion or a guide groove for leading out the terminals of the primary winding and the secondary winding, so that Next winding and 2
This is to prevent a short circuit of the next winding.

[0004]

FIG. 1 is an exploded perspective view showing an example of a combination of cores related to a narrow transformer of the present invention, FIG. 2 is a perspective view showing another example of one core, and FIG. FIG. 4 is a perspective view showing another example of the base according to the present invention, FIG. 5 is a perspective view showing another example of the base, and FIG.
FIG. 3 is a view for explaining an assembled state of the narrow transformer of the present invention.
(A) is a top view, (b) is a partial front view, and (c) is 1
Partial sectional side view, (d) is a bottom view. In the respective drawings, the same parts will be described with the same reference numerals.

[0005] 1 is a narrow strip-shaped I-shaped core, 2 is a narrow strip-shaped E-shaped core, and a middle leg 2c formed at an intermediate portion between the side legs 2a at both ends in the longitudinal direction and the yoke portion 2b. It is composed of Reference numeral 3 denotes a primary winding, 4 denotes a secondary winding, and the primary winding 3 and the secondary winding 4 are mounted concentrically on the middle leg 2c of the E-shaped core 2.
The mold core 1 forms a closed magnetic path by joining between the side legs 2a of the E-shaped core 2. Reference numeral 5 denotes a yoke portion 2b of the E-shaped core where the terminal of the primary winding 3 or the terminal of the secondary winding 4 is located.
A step formed at a position lower than the surface from which the center leg 2c protrudes, and the step is provided such that the terminal of the primary winding and the terminal of the secondary winding are led out without contacting each other. The guide groove 6 may be formed by cutting out a part of the yoke part 2b as shown in FIGS. In addition, as shown in FIG.
It can be provided on the I-shaped core 1 as needed. Reference numeral 7 denotes a base provided with a terminal 8 for connecting the terminal of the primary winding 3 or the secondary winding 4. 9 is a guide plate for the primary winding 3
Alternatively, it has a guide groove 10 for guiding the terminal of the secondary winding 4 to the terminal 8 of the base 7, and the guide plate is provided on the base 7.
It is attached to the outer peripheral surface. In this embodiment, the cores 1 and 2 are attached along the longitudinal side ends at the bottom surface of the base. Reference numeral 11 denotes a bottom surface at both ends in the longitudinal direction of the E-shaped core 2, that is, a concave notch formed on the bottom surface of the side leg 2 a. It is designed to engage with the notch 11.

Next, an assembly structure of the narrow transformer according to the present invention will be described with reference to FIG. In the figure, it is assumed that the E-shaped core 2 has a concave leg 11 formed on the side leg 2a, and the base 7 has a plate-shaped portion 12 provided thereon. In this configuration, the primary winding 3 and the secondary winding 4 are mounted concentrically on the middle leg 2c of the E-shaped core 2, and the I-shaped core 1 is bonded between the side legs 2a of the E-shaped core. To form a closed magnetic circuit. The base 7 has a plate-like portion 12 attached and fixed to a recessed portion 11 formed on the outer bottom surface of the side legs 2a, 2a of the E-shaped core 2 by an adhesive or the like. The bottom is flush with the bottom. Also, the terminal of one of the windings is pulled out of the guide groove 6 provided in the yoke portion 2b of the E-shaped core so that the terminal of the primary winding 3 and the terminal of the secondary winding 4 do not contact each other. The terminal of another winding is drawn out from the guide groove 6 provided in the I-shaped core 1 and connected to another terminal through a guide groove 10 provided in the 9.

[0007]

According to the present invention, as described above, two bases provided with terminals are respectively mounted on opposite ends of a narrow strip-shaped core in the longitudinal direction, and the bottom surface of the base and the bottom surface of the core are flush with each other. Since the base portion at the center of the core is omitted, the thickness can be made extremely thin and low. In addition, since a step or a groove is formed at the leading end of the winding end of the core to prevent contact between the primary winding and the secondary winding, the withstand voltage is improved while being thin and low-profile. I can do it.

[Brief description of the drawings]

FIG. 1 is an exploded perspective view showing an example of a combination of cores according to the narrow transformer of the present invention, FIG. 2 is a perspective view showing another example of one core, and FIG. 3 is a further example of one core. FIG. 4 is a perspective view showing an example of a base according to the present invention, FIG. 5 is a perspective view showing another example of the base, and FIG. 6 is a view for explaining an assembled state of the narrow transformer of the present invention. (A) is a top view, (b) is a front view in partial section, (c) is a side view in partial section, and (d) is a bottom view.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... I type core, 2 ... E type core 3 ... Primary winding, 4 ... Secondary winding, 5 ... Step part, 6 ... Guide groove, 7 ...・ Base, 8 ・ ・
・ Terminal, 9 ・ ・ ・ Guide plate, 10 ・ ・ ・ Guide groove, 1
1 ... concave notch, 12 ... plate-shaped part

Claims (5)

[Claims] 1. A narrow and long strip-shaped core forming a closed magnetic circuit, a primary winding and a secondary winding concentrically mounted on a middle leg formed on at least one of the cores, and each of the windings And two bases provided with terminals for connecting the terminals. Each of the bases is mounted opposite to both ends in the longitudinal direction of a core forming a closed magnetic circuit so that the bottom surface of the base and the bottom surface of the core are flush with each other. A narrow type transformer characterized by becoming. 2. A guide plate having a guide groove for guiding a terminal of a primary winding or a secondary winding to a terminal is attached to an outer peripheral surface of at least one of the two bases. The narrow-width transformer according to claim 1. 3. The narrow-width transformer according to claim 2, wherein the guide plate is arranged along a longitudinal direction of the core. 4. The narrowing according to claim 1, wherein a concave portion is formed on the bottom surface at both ends in the longitudinal direction of the core, and a base is mounted in the concave portion. Wide transformer. 5. A step or a guide groove for leading out terminals of a primary winding and a secondary winding is formed on at least one of the cores forming a closed magnetic circuit. The narrow-width transformer according to claim 1.