阅读说明：本技术 用于改善性能的采用绝缘结构的平面变压器 (Planar transformer with insulation structure for improving performance ) 是由 李株悦 于 2019-09-27 设计创作，主要内容包括：根据本发明的一个实施例的用于改善性能的采用绝缘结构的平面变压器,其特征在于,包括：一对铁氧体磁芯(110),其包括上部磁芯(110-1)和下部磁芯(110-2)；印刷电路板(120),其配置于一对铁氧体磁芯(110)之间,一端设置有电气连接第一侧线圈图案的第一侧通路孔(121),另一端设置有电气连接第二侧线圈图案的第二侧通路孔(123)；绝缘块体(130-1),其收容一对铁氧体磁芯(110)的一侧；以及绝缘基底(130-2),其配置于一对铁氧体磁芯(110)内,和绝缘块体(130-1)嵌入结合；绝缘块体(130-1)及绝缘基底(130-2)在设置有第二侧通路孔(123)的一侧收容印刷电路板(120)的一部分区域。(The planar transformer using an insulation structure for improving performance according to an embodiment of the present invention is characterized by comprising: a pair of ferrite cores (110) including an upper core (110-1) and a lower core (110-2); a printed circuit board (120) disposed between the pair of ferrite cores (110), having a first side via hole (121) at one end thereof for electrically connecting the first side coil pattern, and a second side via hole (123) at the other end thereof for electrically connecting the second side coil pattern; an insulating block (130-1) that houses one side of the pair of ferrite cores (110); and an insulating base (130-2) disposed in the pair of ferrite cores (110) and embedded and coupled to the insulating block (130-1); the insulating block (130-1) and the insulating base (130-2) receive a part of the area of the printed circuit board (120) on the side where the second side via hole (123) is provided.)

1. A planar transformer employing an insulating structure for improved performance, comprising:

a pair of ferrite cores (110) including an upper core (110-1) and a lower core (110-2);

a printed circuit board (120) disposed between the pair of ferrite cores (110), having a first side via hole (121) at one end thereof for electrically connecting the first side coil pattern, and a second side via hole (123) at the other end thereof for electrically connecting the second side coil pattern;

an insulating block (130-1) that houses one side of the pair of ferrite cores (110); and

an insulating base (130-2) disposed in the pair of ferrite cores (110) and embedded and coupled to the insulating block (130-1);

the insulating block (130-1) and the insulating base (130-2) receive a part of the area of the printed circuit board (120) on the side where the second side via hole (123) is provided.

2. The planar transformer with insulation structure for improving performance as claimed in claim 1, wherein the insulation substrate (130-2) comprises:

a first base insulating surface (135) connected to the center legs (112) of the pair of ferrite cores (110); and

and a second base insulating surface (136) extended from the first base insulating surface (135) and connected to the upper and lower sides of the printed circuit board (120), respectively.

3. The planar transformer with insulation structure for improving performance according to claim 2, wherein the insulation block (130-1) further comprises:

and a first block insulating surface (137) inserted to one side of the pair of ferrite cores (110) and embedded-coupled with the second base insulating surface (136).

4. The planar transformer with insulation structure for improving performance according to claim 3, wherein the insulation block (130-1) further comprises:

and a second block insulating surface (138) which is inserted into one side of the pair of ferrite cores (110) and which accommodates a part of the outer exposed surfaces of the upper core (110-1) and the lower core (110-2).

5. The planar transformer with insulation structure for improving performance as claimed in claim 3,

the upper magnetic core (110) and the lower magnetic core (110) are provided with an insulating accommodating surface (116) on the inner side surface where the printed circuit board (120) is arranged, and the second substrate insulating surface (136) and the first block insulating surface (137) which are embedded and combined are arranged on the insulating accommodating surface (116).

6. The planar transformer with insulation structure for improving performance as claimed in claim 4,

the shortest straight-line distance from the outer side surface of the midfoot (112) to the second side passage hole (123) is 7mm or less.

7. The planar transformer with insulation structure for improving performance as claimed in claim 4,

the insulating block (130-1) further comprises a third block insulating surface (139) connecting the first block insulating surface (137) and the second block insulating surface (138),

the third block insulating surface (139) is provided with a hole (H) for exposing the printed circuit board (120) to the outside of the pair of ferrite cores (110), wherein the printed circuit board (120) is provided with a second side via hole (123).

Technical Field

The present invention relates to a planar transformer having an insulation structure for improving performance, in which an insulation distance between a first side member, which is a component of the transformer, and a second side via hole of a printed circuit board can be secured by an additional insulation block without extending a length of a coil pattern formed on the printed circuit board.

Background

The charger for charging the battery for the mobile equipment is connected to the common voltage which is popularized in families, and charges the battery after converting the common voltage into the voltage which is suitable for charging the battery. In this case, a common voltage that is commonly used in homes is an ac voltage of 220V, and a voltage for charging a battery is 5V. Therefore, the charger reduces the 220V normal voltage to 5/9/12/20V and converts the voltage into dc voltage to charge the battery, and the transformer is used as a component of the charger that functions to convert the 220V normal voltage into 5/9/12/20V low voltage.

In order to perform such a function, the transformer includes a first side winding that is switched in a common voltage and a second side winding that outputs a voltage lower than the common voltage. If an alternating current flows in the first side winding, the alternating current is induced to the second side winding and flows, and the load is connected to 2 second side pin type terminals connected to the second side winding, thereby the load operates by obtaining the current flowing in the second side pin type terminals.

In addition, the transformer is being developed in a direction of miniaturization and weight reduction, and the first side member and the second side member need to be maintained at a predetermined distance for electrical stability during operation, and thus there is a limitation in miniaturization. Therefore, although the prior publication No. 10-2017-0142261 "transformer for charger with improved insulation structure" discloses a technique for reducing the thickness of the transformer by attempting to miniaturize the transformer while securing the insulation distance, the entire area constituting the transformer is increased (the length of the coil pattern formed on the printed circuit board is increased), and thus complete miniaturization of the transformer cannot be achieved.

Therefore, there is a demand for development of a technique that can miniaturize the size of a transformer while securing electrical stability of the transformer, and the present invention relates to the technique.

Disclosure of Invention

The technical problem to be solved by the invention is to ensure the insulation distance between a first side component (ferrite core) as a component of a transformer and a second side via hole of a printed circuit board.

Another object of the present invention is to provide a planar transformer in which the resistance component of the transformer is reduced to improve the efficiency of the transformer and to reduce the size of the entire product.

Another object of the present invention is to provide a planar transformer in which an insulating block capable of securing an insulating distance is inserted so as to wrap at least a part of a region of a ferrite core, and two insulating blocks are fitted and coupled to each other, thereby improving coupling force between components of the transformer.

The technical problem of the present invention is not limited to the above-mentioned technical problem, and general technicians can clearly understand other technical problems not mentioned from the following description.

The planar transformer using an insulation structure for improving performance according to one embodiment of the present invention includes: a pair of ferrite cores 110 including an upper core 110-1 and a lower core 110-2; a printed circuit board 120 disposed between the pair of ferrite cores 110, having a first side via hole 121 electrically connected to the first side coil pattern at one end thereof and a second side via hole 123 electrically connected to the second side coil pattern at the other end thereof; an insulating block 130-1 which receives one side of the pair of ferrite cores 110; and an insulating base 130-2 disposed in the pair of ferrite cores 110 and embedded and coupled with the insulating block 130-1; the insulation block 130-1 and the insulation base 130-2 may receive a portion of the area of the printed circuit board 120 provided with the second side via hole 123.

According to one embodiment, the insulating substrate 130-2 may further include: a first base insulating surface 135 connected to the center legs 112 of the pair of ferrite cores 110; and a second base insulating surface 136 extended from the first base insulating surface 135 and connected to the upper and lower sides of the printed circuit board 120, respectively.

According to one embodiment, the insulation block 130-1 may further include: the first block insulating surface 137, which is inserted to one side of the pair of ferrite cores 110, is embedded and combined with the second base insulating surface 136.

According to one embodiment, the insulation block 130-1 may further include: and a second block insulating surface 138 inserted into one side of the pair of ferrite cores 110 and receiving a part of the outer exposed surface of the upper core 110-1 and the lower core 110-2.

According to an embodiment, the upper core 110 and the lower core 110 may be provided with an insulation receiving surface 116 on the inner side surface where the printed circuit board 120 is disposed, and the insulation receiving surface 116 receives the second base insulation surface 136 and the first block insulation surface 137 which are embedded and combined.

According to one embodiment, the shortest straight distance from the lateral side of the midfoot 112 to the second side passage hole 123 is 7mm or less.

According to one embodiment, the insulation block 130-1 further includes a third block insulation surface 139 connecting the first block insulation surface 137 and the second block insulation surface 138, and the third block insulation surface 139 may be provided with a hole H exposing the printed circuit board 120 to the outside of the pair of ferrite cores 110, wherein the printed circuit board 120 is provided with the second side via hole 123.

According to the present invention, it is possible to secure an insulation distance between the first side and the second side of at least 7mm or more while miniaturizing the transformer, by inserting an additional insulation block and an insulation substrate, even without expanding a coil pattern length formed on the printed circuit board and the printed circuit board.

In addition, the length of the coil pattern formed on the printed circuit board is not increased, and the resistance component is reduced, thereby having the effects of not only increasing the efficiency of the transformer, but also miniaturizing the overall size of the product, and saving the cost in manufacturing the product.

In addition, the insulation blocks, which provide electrical stability and enable miniaturization of products, are firmly coupled to each other, thereby having an effect in that the transformer can be firmly connected even without additional adhesion parts.

The effects of the present invention are not limited to the above-mentioned effects, and those skilled in the art can clearly understand other effects not mentioned from the following description.

Drawings

Fig. 1 is a perspective view illustrating a planar transformer employing an insulation structure for improving performance according to a first embodiment of the present invention.

Fig. 2 is an exploded perspective view of a planar transformer employing an insulation structure for improving performance according to a first embodiment of the present invention, as seen from an upper side.

Fig. 3 is an exploded perspective view of a planar transformer employing an insulation structure for improving performance according to a first embodiment of the present invention, as seen from the lower side.

Fig. 4 (a) and (b) are perspective views illustrating a coupling manner of an insulating block and an insulating base according to a first embodiment of the present invention.

Fig. 5(a), (b) and (c) are perspective views showing a coupling manner of the insulating block body and the lower core according to the first embodiment of the present invention.

Fig. 6 is a plan sectional view for explaining the shortest insulation distance between a pair of ferrite cores and the second side via hole according to the first embodiment of the present invention.

Fig. 7 is a perspective view illustrating a planar transformer employing an insulation structure for improving performance according to a second embodiment of the present invention.

Fig. 8 is an exploded perspective view of a planar transformer employing an insulation structure for improving performance according to a second embodiment of the present invention, as seen from an upper side.

Fig. 9 is an exploded perspective view of a planar transformer employing an insulation structure for improving performance according to a second embodiment of the present invention, as seen from the lower side.

Fig. 10 is an upper view of a transformer according to a second embodiment of the present invention.

Fig. 11 is a flat sectional view of a transformer according to a second embodiment of the present invention.

Fig. 12 is a sectional view of the transformer shown in fig. 10 taken along line a-a'.

Fig. 13 is a sectional view of the transformer shown in fig. 10 taken along line B-B'.

Fig. 14(1) and (2) are plan sectional views comparing insulation distances according to structures of a transformer of the related art and the transformer according to the first embodiment of the present invention, respectively.

Fig. 15(1) and (2) are diagrams illustrating comparison of sizes of second side coil patterns of the transformer according to the first embodiment of the present invention and the conventional art, respectively.

Fig. 16(1) and (2) are diagrams comparing the number of printed circuit boards obtainable in the same circular plate by the transformer according to the prior art and the first embodiment of the present invention, respectively.

Fig. 17(1) and (2) are diagrams for explaining resistance values of the second side coil patterns of the transformer according to the related art and the first embodiment of the present invention, respectively.

Description of the reference symbols

100: planar transformer

110: ferrite magnetic core

110-1: upper core 110-2: lower magnetic core

111: upper core side surface 113: lower magnetic core side

112: middle foot

114: first outer foot 115: second outer foot

116: insulating receiving surface

120: printed circuit board

121: first side via hole 123: second side via hole

130-1: insulating block 130-2: insulating substrate

131: block outer insulating surface 132: internal insulation surface of block

133: substrate outer insulating surface 134: internal insulating surface of substrate

135: first base insulating surface 136: second substrate insulating surface

137: first block insulating surface 138: second block insulating surface

139: third block insulating surface

147: first lead pin 149: second lead pin

150: coil pattern 151: current density

Detailed Description

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. The advantages and features of the invention, and the manner of attaining them, will become apparent with reference to the embodiments described in detail hereinafter and with reference to the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below, and various different embodiments may be implemented, and the embodiments are provided only for the purpose of completely disclosing the present invention and completely informing a person having ordinary knowledge in the art to which the present invention pertains of the scope of the present invention, and the present invention is defined only by the scope of the claims. Like reference numerals refer to like elements throughout the specification.

Unless otherwise defined, all terms (including technical and scientific terms) used in the present specification may be used in the meaning commonly understood by one having ordinary knowledge in the technical field to which the present invention belongs. In addition, terms defined in a dictionary generally used are not ideal or excessively interpreted unless specifically defined. The terminology used in the description is for the purpose of describing the embodiments and is not intended to be limiting of the invention. In this specification, the singular forms also include the plural forms as long as the text does not specifically refer thereto.

The use of "including" and/or "comprising" in this specification does not preclude the presence or addition of one or more other components, steps, operations and/or elements.

The present invention will be described in detail below with reference to the accompanying drawings.

Fig. 1 is a perspective view illustrating a planar transformer 100 employing an insulation structure for improving performance according to a first embodiment of the present invention, fig. 2 is an exploded perspective view of the planar transformer 100 employing an insulation structure for improving performance according to the first embodiment of the present invention, viewed from an upper side, and fig. 3 is an exploded perspective view of the planar transformer 100 employing an insulation structure for improving performance according to the first embodiment of the present invention, viewed from a lower side.

Referring to fig. 1 to 3, a planar transformer 100 (hereinafter, referred to as a transformer) using an insulation structure for improving performance of the present invention includes: a pair of ferrite cores 110 including an upper core 110-1 and a lower core 110-2 electromagnetically coupled to each other; a printed circuit board 120 disposed in an internal space formed by the pair of ferrite cores 110; an insulation block 130-1 and an insulation base 130-2, which ensure an insulation distance between the pair of ferrite cores 110 and the printed circuit board 120.

The pair of ferrite cores 110 may form an inner space in which a conversion process that may step up or down a voltage input through the transformer 100 is performed. For this, in order to make the upper core 110-1 and the lower core 110-2 have a flat E-shape when the pair of ferrite cores 110 are viewed in a vertical cross section, a first outer leg 114, a middle leg 112, and a second outer leg 115 may be respectively included, and a front-rear direction may be opened so as to expose a partial area of the printed circuit board 120. However, the upper core 110-1 and the lower core 110-2 may have various shapes without limitation. For example, the upper core 110-1 and the lower core 110-2 may have E-I and I-I cross sections, respectively.

For reference, the front-back direction in the present invention is understood to mean that the side where the insulation block 130-1 is not disposed is the front side and the side where the insulation block 130-1 is disposed is the back side when viewed with reference to the transformer 100 of fig. 1.

In addition, the pair of ferrite cores 110 may be formed of ferrite materials so as to be electromagnetically coupled to each other. Since the cores of the transformer 100 are made of ferrite material, the pair of ferrite cores 110 can use magnetic characteristics according to the switching frequency of the power supply circuit within several hundred kHz and can use a high frequency band, and thus the transformer 100 can be miniaturized and made lighter than a capacity capable of converting electric power. In addition, the electric loss rate is low, so that the eddy current loss can be reduced in a high frequency band.

The printed circuit board 120 may include a first side coil pattern and a second side coil pattern that boost or buck a voltage. Specifically, the induced electromotive force generated at the first side coil pattern is guided to the second side coil pattern by means of the current introduced to the first side via hole 121 provided at one end of the printed circuit board 120, and is outputted through the second side via hole 123 provided at the other end of the printed circuit board 120.

In this manner, in order to input or output a voltage to or from the first side via hole 121 and the second side via hole 123, the printed circuit board 120 may be provided with a first lead pin 147 electrically connected to the first side via hole 121 at one end provided with the first side via hole 121, and may be provided with a second lead pin 149 electrically connected to the second side via hole 123 at the other end provided with the second side via hole 123.

The printed circuit board 120 is disposed in the pair of ferrite cores 110, and an insertion hole 125 into which the center leg 112 of the pair of ferrite cores 110 can be inserted may be formed in the printed circuit board 120.

In addition, one printed circuit board 120 is shown in the present invention, but at least two or more printed circuit boards 120 including coil patterns may be stacked.

The insulation block 130-1 and the insulation base 130-2 are coupled to the pair of ferrite cores 110 and the printed circuit board 120 for electrical stability of the transformer 100, so that an insulation distance between the pair of ferrite cores 110 and the second side via hole 123 can be secured. Here, the insulation distance is the shortest distance from the exposed points of the pair of ferrite cores 110 as the first side member to the second side via hole 123 as the second side member, and the distance measured along the insulation surface should be longer than the standard insulation distance.

Specifically, the insulation block 130-1 may receive one side of the pair of ferrite cores 110, and the insulation base 130-2 may be formedThe shape may be arranged in the pair of ferrite cores 110. In addition, the insulation block 130-1 may be embedded and coupled during the assembly process. That is, the insulation block 130-1 and the insulation substrate 130-2 can be wrappedA part of the area of the printed circuit board 120 where the second side via-hole 123 is disposed is received, whereby the exposed points of the pair of ferrite cores 110 can be distanced from the second side via-hole 123. Accordingly, a standard insulation distance between the first side member and the second side member can be secured even in the printed circuit board 120 having a relatively short length, and in order to secure the standard distance, the length of the coil pattern formed on the printed circuit board 120 can be made not to increase.

The components included in the transformer 100 according to the first embodiment of the present invention have been described briefly, and specific shapes of the insulating block 130-1 and the insulating base 130-2 that can secure a standard insulation distance between the first side member and the second side member in the transformer 100 will be described below.

Fig. 4 (a) and (b) are perspective views illustrating a coupling manner of the insulation block 130-1 and the insulation base 130-2 according to the first embodiment of the present invention, fig. 5(a), (b) and (c) are perspective views illustrating a coupling manner of the insulation block 130-1 and the lower core 110-2 according to the first embodiment of the present invention, and fig. 6 is a plan sectional view for explaining a shortest insulation distance between the pair of ferrite cores 110 and the second side via 123 according to the first embodiment of the present invention.

Referring to fig. 4 (a) and (b), the insulating block 130-1 and the insulating base 130-2 may be formed in a cross-coupled shape, and a partial region of the printed circuit board 120 may be received in a cross-coupled space. Specifically, the insulating substrate 130-2 may include a first substrate insulating surface 135 and a second substrate insulating surface 136, the first substrate insulating surface 135 being connected to a surface where the center legs 112 of the pair of ferrite cores 110 or the insertion holes 125 of the printed circuit board 120 are formed, the second substrate insulating surface 136 being extended from the first substrate insulating surface 135 and being connected to the upper and lower surfaces of the printed circuit board 120, respectively. In other words, the insulating substrate 130-2 hasThe shape is arranged on the surface where the center leg 112 of the pair of ferrite cores 110 and the printed circuit board 120 are connected, so that the insulation distance can be secured.

In addition, the insulation block 130-1 inserted into one side of the pair of ferrite cores 110 may include a first block insulation surface 137 which is insert-coupled with the second base insulation surface 136, and at this time, the first block insulation surface 137 may be provided with a prescribed groove 137-1 so as to be firmly coupled with the second base insulation surface 136, i.e., the insulation base 130-2.

That is, as shown in fig. 5(a), a groove 137-1 may be provided in the first block insulating surface 137 of the insulating block 130-1. The insulation block 130-1 includes a second block insulation surface 138 that can receive a portion of the exposed surfaces of the upper and lower cores 110-1 and 110-2, and can be firmly coupled to the insulation base 130-2 and secure an insulation distance even without an additional adhesion member (e.g., an adhesive, a tape).

Referring to fig. 5(b), when the coupled shape is viewed in a vertical cross section, the insulation receiving surface 116 may be provided on the inner surface of the lower core 110-2 so that the insulation block 130-1 and the insulation base 130-2, which are firmly coupled to each other, are placed on the lower core 110-2. Specifically, the lower magnetic core 110-2 has a thinner thickness at a region where the insulation receiving face 116 is disposed, so that the insulation block body 130-1 can more easily receive the lower magnetic core 110-2.

Although fig. 5(b) is described with reference to the lower core 110-2, the insulating housing surface 116 capable of housing the insulating block 130-1 may be provided on the inner surface of the upper core 110-1.

In addition, referring to fig. 5(c), the insulation block 130-1 may further include a third block insulation surface 139 connecting the first block insulation surface 137 and the second block insulation surface 138 when the combined shape is viewed from below. The third block insulating surface 139 is provided with a hole 139-1 exposing the printed circuit board 120 provided with the second side via hole 123 to the outside of the pair of ferrite cores 110, and the pair of ferrite cores 110 can be stably fixed only by the insertion of the insulating block 130-1.

Referring to fig. 6, a printed circuit board 120 is disposed between a pair of ferrite cores 110, and a first outer leg 114, a middle leg 112, and a second outer leg 115 of the pair of ferrite cores 110 are electromagnetically coupled to each other, thereby providing a moving path of magnetic flux (magnetic flux). Here, the middle leg 112 is inserted into the insertion hole 125 of the printed circuit board 120, and a path for transferring the first and second side magnetic fluxes may be formed. That is, the input current applied to the first side via hole 121 generates an electromotive force by the first side coil pattern in the printed circuit board 120, the electromotive force is guided to the second side coil pattern in the printed circuit board 120, and can be output through the second side via hole 123.

In other words, in order to achieve miniaturization while maintaining the performance of the transformer 100, the insulating base 130-2 is disposed inside the pair of ferrite cores 110, and the insulating blocks 130-1 are disposed outside the pair of ferrite cores 110, each having the facing surfacesAnd are shaped so as to be firmly fitted and bonded to each other.

Further, since the insulation block 130-1 and the insulation base 130-2 are disposed, a portion of the middle leg 112 is insulated to secure an insulation distance by a winding length of the insulation means, and thus, a shortest insulation distance t from the outer side surfaces of the middle legs 112 of the upper and lower cores 110-1 and 110-2 to the second side via hole 123 can be implemented as a straight distance shorter than 7mm, and thus the size of the printed circuit board 120 can be relatively reduced compared to the related art.

The transformer 100 according to the first embodiment of the present invention has been explained so far. According to the present invention, the insulation distance t that should be ensured between the pair of ferrite cores 110 and the second side via holes 123 is ensured by the insulation block 130-1 and the insulation substrate 130-2, so that the length of the coil pattern formed on the printed circuit board 120 can be minimized, wherein the insulation block 130-1 and the insulation substrate 130-2 have a structure wrapping a portion of the area of the printed circuit board 120. In addition, the overall size of the transformer 100 is miniaturized and its performance is improved.

The transformer 100 of yet another structure that can secure the insulation distance is explained below.

Fig. 7 is a perspective view illustrating a planar transformer 100 employing an insulation structure for improving performance according to a second embodiment of the present invention, fig. 8 is an exploded perspective view of the planar transformer 100 employing an insulation structure for improving performance according to the second embodiment of the present invention, viewed from an upper side, and fig. 9 is an exploded perspective view of the planar transformer 100 employing an insulation structure for improving performance according to the second embodiment of the present invention, viewed from a lower side.

Referring to fig. 7 to 9, a transformer 100 according to a second embodiment of the present invention may include: a pair of ferrite cores 110 including an upper core 110-1 and a lower core 110-2 electromagnetically coupled to each other; a printed circuit board 120 disposed in an internal space formed by the pair of ferrite cores 110; an insulating block 130-1 and an insulating base 130-2, which insulate the pair of ferrite cores 110 from the printed circuit board 120.

The pair of ferrite cores 110 may form an inner space in which a conversion process that may step up or down a voltage input through the transformer 100 is performed. For this, in order to make the upper core 110-1 and the lower core 110-2 have a flat E-shape when the pair of ferrite cores 110 are viewed in a vertical cross section, a first outer leg 114, a middle leg 112, and a second outer leg 115 may be respectively included, and a front-rear direction may be opened so as to expose a partial area of the printed circuit board 120. However, the upper core 110-1 and the lower core 110-2 may have various shapes without limitation. For example, the upper core 110-1 and the lower core 110-2 may have E-I and I-I cross sections, respectively.

In addition, the pair of ferrite cores 110 may be formed of ferrite materials so as to be electromagnetically coupled to each other. In this way, the cores of the transformer 100 are made of ferrite material, and the pair of ferrite cores 110 can use magnetic properties according to the switching frequency of the power supply circuit within several hundred kHz. Further, since the usable frequency band is high, the transformer 100 can be downsized compared to the capacity capable of converting electric power, and the weight thereof becomes light. In addition, the electric loss rate is low, so that the eddy current loss can be reduced in a high frequency band.

The printed circuit board 120 may include a first side coil pattern and a second side coil pattern that boost or buck a voltage. Specifically, the induced electromotive force generated at the first side coil pattern is guided to the second side coil pattern by means of the current introduced to the first side via hole 121 provided at one end of the printed circuit board 120, and is outputted through the second side via hole 123 provided at the other end of the printed circuit board 120.

In this manner, in order to input or output a voltage to or from the first side via hole 121 and the second side via hole 123, the printed circuit board 120 may be provided with a first lead pin 147 electrically connected to the first side via hole 121 at one end provided with the first side via hole 121, and may be provided with a second lead pin 149 electrically connected to the second side via hole 123 at the other end provided with the second side via hole 123.

The printed circuit board 120 is disposed in the pair of ferrite cores 110, and an insertion hole 125 into which the center leg 112 of the pair of ferrite cores 110 can be inserted may be formed in the printed circuit board 120.

In addition, one printed circuit board 120 is shown in the present invention, but at least two or more printed circuit boards 120 including coil patterns may be stacked.

The insulation block 130-1 and the insulation base 130-2 may ensure an insulation distance between the pair of ferrite cores 110 and the second side via holes 123 for electrical stability. Here, the insulation distance is the shortest distance from the exposed points of the pair of ferrite cores 110 as the first side member to the second side via hole 123 as the second side member, and the distance measured along the insulation surface should be longer than the standard insulation distance.

Specifically, the insulation block 130-1 and the insulation base 130-2 are formed in a shape of being cross-coupled to each other, and the insulation block 130-1 may include a block outer insulation surface 131 and a block inner insulation surface 132, the block outer insulation surface 131 receiving the upper core side surface 111 and securing an insulation distance, and the block inner insulation surface 132 receiving a portion of the middle leg 112 of the upper core 110-1 and securing an insulation distance. In addition, the insulating base 130-2 may include a base outer insulating surface 133 and a base inner insulating surface 134, the base outer insulating surface 133 receiving the lower core side surface 113 and securing an insulating distance, and the base inner insulating surface 134 receiving a portion of the middle leg 112 of the lower core 110-2 and securing an insulating distance.

Also, the block outer insulating surface 131 and the substrate outer insulating surface 133 of the insulating block 130-1 and the insulating substrate 130-2 may be disposed in a spaced apart manner from the second side via hole 123 of the printed circuit board 120, respectively.

In addition, the insulating base 130-2 may be formed in a structure to receive a pair of the ferrite cores 110 and the insulating blocks 130-1, the insulating base 130-2 receives the lower core 110-2 to the inner side thereof, and the insulating blocks 130-1 to receive the upper cores 110-1 may be mounted thereon. That is, the block external insulation surface 131 and the base external insulation surface 133, and the block internal insulation surface 132 and the base internal insulation surface 134 are cross-coupled to each other, so that a very strong transformer structure can be formed.

The configuration included in the transformer 100 according to the second embodiment of the present invention has been briefly described so far. According to the present invention, the transformer 100 should ensure the insulation distance t between the pair of ferrite cores 110 and the second side via-hole 123, by additionally disposing the insulation block 130-1 and the insulation substrate 130-2 of the particular structure inserted into each other within the transformer 100 as described above, so that it is possible to minimize the length of the coil pattern formed on the printed circuit board 120, achieve the miniaturization of the transformer 100, and improve the performance thereof.

The structure of the insulating block 130-1 and the insulating base 130-2 that can secure the insulating distance will be described in more detail below.

Fig. 10 is an upper view of a transformer 100 according to a second embodiment of the present invention, fig. 11 is a flat sectional view of the transformer 100 according to the second embodiment of the present invention, fig. 12 is a sectional view of the transformer 100 shown in fig. 10 taken along line a-a ', and fig. 13 is a sectional view of the transformer 100 shown in fig. 10 taken along line B-B'.

Referring to fig. 10 to 13, the transformer 100 has a printed circuit board 120 disposed between a pair of ferrite cores 110, and the first outer leg 114, the middle leg 112, and the second outer leg 115 of the pair of ferrite cores 110 are electromagnetically coupled to each other, thereby providing a moving path of magnetic flux (magnetic flux). Here, the middle leg 112 is inserted into the insertion hole 125 of the printed circuit board 120, and a path for transferring the first and second side magnetic fluxes may be formed. That is, the input current applied to the first side via hole 121 generates an electromotive force by the first side coil pattern in the printed circuit board 120, the electromotive force is guided to the second side coil pattern in the printed circuit board 120, and can be output through the second side via hole 123.

In order to achieve miniaturization while maintaining the performance of the transformer 100, the insulation block 130-1 coupled with the upper magnetic core 110-1 and the insulation base 130-2 coupled with the lower magnetic core 110-2 may be coupled to the printed circuit board 120. That is, the insulation block 130-1 coupled with the upper magnetic core 110-1 and the insulation base 130-2 coupled with the lower magnetic core 110-2 may be inserted into the insertion hole 125 of the printed circuit board 120 and coupled with each other. Also, in this process, the pair of ferrite cores 110 wrapping the printed circuit board 120 may be mounted in a structure insulated from the printed circuit board 120 by the insulation block 130-1 and the insulation substrate 130-2.

Further, the insulation block 130-1 combined with the upper magnetic core 110-1 is disposed at the inner side of the insulation base 130-2 combined with the lower magnetic core 110-2, and the block outer insulation surface 131 and the base outer insulation surface 133, the block inner insulation surface 132 and the base inner insulation surface 134 are cross-combined with each other, so that it is possible to have a firm structure which does not shake even if external force is applied.

The structure of the conventional transformer and the structure of the transformer according to the first embodiment of the present invention are compared with each other with reference to the accompanying drawings.

Fig. 14(1) and (2) are plan sectional views comparing insulation distances according to structures of the transformer 100 according to the related art and the first embodiment of the present invention, respectively.

Fig. 14(1) shows a conventional insulating structure, in the prior art, no insulating member is provided between the center leg 212 and the second side via hole 223 of the upper core 210-1 and the lower core 210-2, and the shortest insulating distance t between the center leg 212 and the second side via hole 223 is 7mm or more as a straight distance at least.

In contrast to fig. 14(2), which shows the structure of the transformer 100 of the present invention, the insulation distance is ensured by the detour length of the insulation means by insulating a portion of the center leg 112 by the insulation block 130-1 and the insulation base 130-2, and thus the shortest insulation distance t of the center leg 112 and the second side via hole 123 can be realized to be a straight distance shorter than 7 mm. That is, the size of the printed circuit board 120 may be relatively small compared to the related art.

Fig. 15(1) and (2) are diagrams illustrating comparison of the sizes of the second side coil patterns of the transformer 100 according to the first embodiment of the present invention and the related art, respectively.

Fig. 15(1) shows the shape of the second side coil pattern 250 formed in the printed circuit board 220 in the conventional transformer 200, and fig. 15(2) shows the shape of the second side coil pattern 150 formed in the printed circuit board 120 in the transformer 100 of the present invention, whereby it is known that the size of the second side coil pattern 150 is smaller in the present invention compared to the prior art, and thus the transformer 100 can be more miniaturized.

Fig. 16(1) and (2) are diagrams comparing the number of printed circuit boards obtainable in the same circular plate by the transformer 100 according to the prior art and the first embodiment of the present invention, respectively.

Referring to fig. 16, the size of a circular plate used for manufacturing a multi-layer printed circuit board is generally 1000x1000mm, and as shown in fig. 16(1), about 2,009 printed circuit boards (19.15 × 22.8mm) can be produced in one circular plate in the case of the printed circuit boards used for the conventional transformer, but as shown in fig. 16(2), about 2,205 printed circuit boards (19.15 × 21.0mm) can be produced in one circular plate in the case of the printed circuit boards used for the transformer of the present invention.

That is, 196 printed circuit boards can be produced in a large number by one and the same circular plate, which can save about 10% of the cost and is more economical.

Fig. 17(1) and (2) are diagrams for explaining resistance values of the second side coil patterns of the transformer 100 according to the first embodiment of the present invention and the related art, respectively.

Referring to fig. 17(1), it was confirmed that, when the switching frequency of the charger circuit of the conventional transformer was 100kHz, the output voltage and the output current were 5V/3A, the ac resistance component was 42.1(m, ohm) and the second-side output power was 15W according to the same temperature of the printed circuit board and the lower surface of the printed circuit board at the current density 251, the power loss due to the resistance 42.1(m, ohm) was 378.9 mW.

In contrast, referring to fig. 17(2), it was confirmed that the switching frequency of the charger circuit of transformer 100 of the present invention was 100kHz, the output voltage and the output current were 5V/3A, the ac resistance component was 31.8(m, ohm) and the power loss due to resistance 31.8(m, ohm) was 286.2mW when the temperature of printed circuit board 200 was the same as the lower surface and the second-side output power was 15W according to current density 151, and thus the power loss was less than that of the conventional art.

That is, the transformer 100 of the present invention is inserted with the insulation block 130-1 and the insulation base 130-2, so that the power loss can be reduced by about 25% as compared with the conventional art.

In addition, although the comparison between the prior art and the present invention is described with reference to the first embodiment, it is understood that the same effect can be obtained by disposing the insulating block 130-1 and the insulating base 130-2 in the second embodiment of the present invention.

While the embodiments of the present invention have been described with reference to the drawings, it is to be understood that a person having ordinary knowledge in the art to which the present invention pertains may practice the present invention in other specific forms without changing the technical ideas or essential features thereof. Therefore, it should be understood that the above-described embodiments are illustrative in all respects and are not restrictive.