TWI584311B - Coil for planar transformer and planar transformer using the same - Google Patents

Description

Planar coil and planar transformer of planar transformer

The present invention relates to a planar coil of a planar transformer and a planar transformer using the same, and more particularly to a multilayer, multi-turn planar coil structure that can be fabricated from a continuous material. The invention also discloses a planar transformer using the planar coil.

Transformers are an important component in the supply of electronic products. The conventional transformer is bulky and cannot meet the requirements for miniaturization of the product. A planar transformer (a planar transformer) is a transformer in which a conductive foil such as a copper foil is laid on a multilayer printed circuit board (PCB) as a winding, and the thickness of the transformer can be greatly reduced. Planar transformers are widely used in communications, computers, industrial control, aerospace engineering, medical equipment and other products. However, because flat-panel transformers require a relatively large number of boards, they are still large. And because the efficiency is not high, the output impedance is also large, and it is easy to generate noise. How to achieve a thinner and more efficient planar transformer has become a technical problem that needs to be overcome in this industry.

Taiwan Patent No. I357086 provides a transformer suitable for being disposed in a circuit substrate. The transformer includes a first planar coil and a second planar coil, wherein the first planar coil has a plurality of first windings and the second planar coil has a plurality of second windings. At least two adjacent first windings constitute a first winding bundle. At least two adjacent second windings constitute a second winding bundle. The two cross each other, thereby reducing the number of layers of the planar coil.

Chinese invention patent CN 103081044A discloses a planar transformer having a plurality of layers of single-layer, single-turn wound plates, and combining different winding plates to form different types of planar transformers according to different needs.

European patent EP 2 602 801 A1 discloses a planar transformer having a plurality of single-layer, single-turn wound metal sheets as secondary windings for combination with primary windings.

European patent EP 2 637 183 A2 discloses a planar transformer using a single layer single-turn wound plate as a coil. The bobbin is stretched out of the shape of a pad to serve as a layer-to-layer and connection electrode to the outside.

U.S. Patent Publication No. 2013-278371 A1 discloses a planar transformer which uses a plurality of single-layer planar metal windings and connects and positions a plurality of metal windings in series to achieve multilayer winding.

The Patent Cooperation Treaty patent application WO 0070926 A1 also discloses a planar transformer which uses a continuous material to make a multilayer, single-turn wound plate. The tongues in the shape of a pad are connected in series between the layers.

U.S. Patent No. 8,237,535 B2 discloses a planar transformer in which a multilayer coil plate or coil is laminated. Each coil layer includes a single turn of coil.

U.S. Patent No. 8,395,470 B2 discloses a planar transformer in which a multilayer coil plate or coil is laminated. Each of the coil layers includes a single-turn coil that is connected in series with pads that are disposed at different relative positions.

U.S. Patent Publication No. 2014/0145813 discloses a planar high voltage transformer formed using a plurality of stacked coil plate stacks. Each coil plate includes a plurality of coils. The winding of the coil starts from the outer circumference of the coil plate and finally the inner circumference.

From the state of the art of planar transformers, the industry has made great efforts to miniaturize planar transformers, in order to get rid of the knack of making planar transformers with printed circuit boards. The proposed design mostly uses a single-layer wound plate, a coil plate or a coil layer as a combined unit. However, it is not possible to propose a planar transformer structure that can change the voltage conversion ratio of the transformer by increasing or decreasing the number of coil plates or coil layers and the number of coils according to the needs of use. The prior art also does not suggest a technique for making planar coils from continuous materials.

It is an object of the present invention to provide a multilayer, multi-turn planar coil architecture.

Another object of the present invention is to provide a planar coil that easily changes the number of layers and the number of turns of a planar coil in response to different needs in use.

It is an object of the present invention to provide a planar coil that can be fabricated using continuous materials.

It is an object of the invention to provide a planar transformer having the above advantages.

A coil of a planar transformer according to the present invention is a planar coil and includes a continuous material: a first scroll coil layer, a second scroll coil layer, and N scroll coil layers in series, the first First, the second and N spiral coils are stacked. Where N is 0 or a double number. The scroll has a winding of a double number of turns or a single number of turns. The joint of any two scroll coil layers connects the plane of the two coil layers. The first or second scroll coil layer may further include an extended pad. The planar coil may further comprise an insulating spacer positioned between any two of the scroll layers.

In an example of the invention, the scroll comprises a scroll formed in a rectangle, a polygon or a circle. In a preferred embodiment of the invention, the coil layers of each layer contain the same number of windings.

In a preferred embodiment of the invention, the insulating spacer forms a port for the connection The knot is broken.

In a preferred embodiment of the invention, at least one of the adjacent two coil layers is provided on a bottom plate. The bottom plate is an electrically insulating sheet material. In other preferred embodiments, the winding of each coil layer includes a cladding material that coats the winding material. The covering material is a material that is electrically insulating.

In some instances of the invention, each loop winding is formed substantially one revolution.

A planar transformer using the planar coil of the present invention can include the planar coil, at least a second coil, and a core. The planar coil is overlapped with the second coil, the core extending in a direction perpendicular to a plane of the two coils and passing through a central portion of the two coils. The planar transformer may further include a metal casing covering the core and the coil portion of the two coils.

In some examples of the invention, the second coil is a planar coil of the invention. In such an example, the layers of the two sets of planar coils are interspersed with each other.

The above and other objects and advantages of the present invention will become more apparent from the detailed description and appended claims.

1‧‧‧Transformer

10‧‧‧First scroll coil layer

11‧‧‧ pads

14‧‧‧Connecting Department

20‧‧‧Second scroll coil layer

21‧‧‧ pads

22‧‧‧Outer loop winding

23‧‧‧Inner loop winding

24‧‧‧Connecting Department

30‧‧‧Second layer coil

32‧‧‧Outer loop winding

33‧‧‧ inner ring winding

34‧‧‧Connecting Department

40‧‧‧ third layer coil

42‧‧‧Outer loop winding

43‧‧‧ inner ring winding

100‧‧‧ planar coil

200‧‧‧second coil

300‧‧‧ iron core

410‧‧‧Upper casing

420‧‧‧ Lower case

Fig. 1 is a view showing the structure of an embodiment of a planar coil of the present invention.

Fig. 2A-2F is a flow chart showing the manufacturing process of the plane coil of Fig. 1.

Fig. 3 is a view showing the structure of an embodiment of the planar transformer of the present invention.

Several embodiments of the planar coil and planar transformer of the planar transformer of the present invention are described below in accordance with the drawings. However, it should be noted that the description of the embodiments of the present invention is merely illustrative of the present invention. The basic architecture and possible applications are not intended to limit the scope of the invention.

The present invention proposes a novel structure of a planar coil of a planar transformer. According to the present invention, a planar coil for use with a planar transformer can be fabricated from a continuous material. Under the planar coil structure proposed by the present invention, the number of winding layers and the number of turns of the continuous material planar coil can be arbitrarily determined according to the application requirements. The only limitation is that the number of winding layers of the continuous material planar coil is a double number. Accordingly, the present invention provides a planar coil structure that is substantially unlimited in number of turns and that is not limited to the number of layers.

A planar coil of a planar transformer according to the present invention is a planar coil made of a continuous material. Since it can be made of continuous materials, it is possible to use a simple working machine and continuously make a large number of productions after setting parameters such as the number of layers, the number of turns, the layer spacing and the pitch.

Fig. 1 is a schematic view showing the structure of an embodiment of a planar coil of a planar transformer of the present invention. The figure shows a planar coil 100 that has been fabricated in accordance with an embodiment of the present invention. The planar coil 100 includes a continuous material: a first scroll coil layer 10 positioned in the upper first layer in the figure, a second scroll coil layer 20 positioned in the lowermost portion of the figure, that is, the fourth layer, and two locations The second and third spiral coil layers 30, 40 of the two are connected in series. The figure also shows that the first layer coil 10, the second layer coil 30, the third layer coil 40 and the fourth layer coil 20 are sequentially connected in series and stacked. The first scroll coil layer 10 and the outer side ends of the second scroll coil layer 20 respectively extend to form pads 11 and 21.

Although the planar coil 100 shown in the drawing contains four coil layers, it can be understood by those skilled in the art that the number of coil layers between the first scroll coil layer 10 and the second scroll coil layer 20 is a double number. That is, the planar coil 100 is required to extend from the outside of the coil, for example, the pad 11, into the coil structure, and the coil structure is extended from the outside of the coil, for example, the pad 21. Accordingly, the number of layers of the coil layer between the first scroll coil layer 10 and the second scroll coil layer 20 Can be 0, 2, 4 and so on. Of course, depending on the thickness of the coil winding material and the required voltage conversion ratio, and the power at the time of application, the total number of coil layers of the planar coil 100 should not be too large, so as not to affect the efficiency of the transformer.

Similarly, according to the design of the present invention, the number of spiral windings of each coil layer is not limited. As shown in the following description, the winding of each layer includes a plurality of turns extending from the outer circumference to the inner circumference or from the inner circumference to the outer circumference. Each circle essentially forms a week. The winding of the adjacent two coil layers, if one layer extends from the outer circumference to the inner circumference, the winding of the other layer extends from the inner circumference to the outer circumference. vice versa. Under this design, there is no limit to the number of spiral wraps of each layer. However, depending on the width of the coil winding material design, the voltage conversion ratio of the required planar coil, the diameter of the core, and the size of the transformer when applied, the number of coils included in each coil layer should not be too large. In a preferred embodiment of the invention, the number of coils included in each layer of the coil layer is the same. It is not a technical limitation to take advantage of its convenience.

The planar coil 100 is fabricated from a continuous material such that the windings in each layer of the coil layer are substantially in the same plane. The two coil layers are connected by a connecting portion 14. The joint of any two scroll coil layers connects the plane of the two coil layers. In some embodiments of the invention, the planar coil 100 may further include an insulating spacer (not shown) positioned between any two of the scroll layers. If necessary, the insulating spacer can form a port for the connecting portion 14 to be inserted. The material of the insulating gasket can be any commercially available insulating material as long as it is suitable for processing and provides good insulation. The thickness should not be too thick, but it should not be too thin, so as to damage and its insulation effect and fixing function.

The planar coil 100 of the present invention can be fabricated from any electrically conductive material. Suitable materials include various metals or alloys such as aluminum, copper, silver, brass, and the like. The material of the planar coil 100 may further include an insulating layer covering the winding. Suitable materials include any commercially available insulation materials, as long as appropriate It can be processed and provides good insulation effect. The thickness is not limited, but it is preferable to use a material with good ductility to avoid being affected by processing.

The windings of the coil layers of each layer form a spiral shape. Includes a scroll formed by a rectangle, a polygon, or a circle. However, from the viewpoint of easy processing, the scroll is preferably formed by a circular shape. The thickness and width of each winding, as well as the maximum and minimum diameter of the scroll, are not limited. In some examples of the invention, the turns of the loops are formed substantially one revolution to maximize the angle of the windings. However, considering that the connecting portion 14 is connected to the characteristics of the adjacent two planes, if it is necessary to form the windings of the respective circles substantially one turn, all the connecting portions will be positioned at the same projection plane position. Therefore, it is conceivable to apply the position of the connection portion evenly in application. Of course, in this example, not every turn of the loop forms a substantial one week.

In a preferred embodiment of the invention, at least one of the adjacent two coil layers is provided on a bottom plate. The bottom plate is an electrically insulating sheet material.

A method of fabricating the planar coil 100 will be described below. 2A-2F is a flow chart showing the manufacturing process of the planar coil 100 shown in Fig. 1. As shown in FIG. 2A, when the planar coil 100 is fabricated, the second spiral coil layer 20 is first formed using a continuous material. The second scroll coil layer 20 has a pad 21, an outer ring winding 22 and an inner ring winding 23. Each of the windings 22, 23 is a substantially flat material layer. The pad 21 extends from the windings 22, 23 and can extend in a vertical direction to reach the plane of the pad 21. Next, as shown in FIG. 2B, the second spiral coil layer 20 (the fourth layer on the structure) and the third spiral coil layer 40 are formed on the inner winding 23 of the second scroll coil layer 20. The connecting portion 24, and then the inner ring winding 43 of the third layer of the spiral coil layer 40 is formed by the connecting portion 24, and extends to form the outer ring winding 42 thereof. Figure 2C shows the completed third layer of scroll coil layer 40. Next, as shown in FIG. 2D, the outer ring winding 42 of the third layer scroll coil layer 40 continues to be extended. Extending the connection portion 34 between the third layer of the spiral coil layer 40 and the second layer of the spiral coil 30, and then forming the outer ring winding 32 of the second layer of the spiral coil layer 30, and the inner ring thereafter Winding 33. Figure 2E shows the completed second layer of scroll coil layer 30. Thereafter, as shown in FIG. 2F, the inner layer winding 33 of the second layer of the spiral coil layer 30 continues to extend to form a first layer of the spiral coil layer, that is, the first scroll coil layer 10 and the second layer vortex The connecting portion 14 between the coils 30 is formed, and then the first scroll coil layer 10 is formed. Fig. 1 shows the completed first scroll coil layer 10. Thus, the fabrication of the planar coil 100 of the present invention is completed.

Suitable methods of forming the single material planar coil 100 include any metalworking technique. Suitable techniques include known techniques such as low temperature deformation, high temperature deformation, cutting, stamping, or the like. In a preferred embodiment of the invention, the planar coil 100 is formed in a low temperature deformation manner. A guiding groove is formed by using a mold, and the material of the planar coil 100 is extruded into the groove to form a continuous layer of coil layers, and then the pads are formed by punching. The fabrication of the planar coil 100 of the present invention can be accomplished.

Figure 1 shows that the pads 11, 21 of the planar coil 100 are in adjacent positions and are at the same height. This design facilitates surface bonding. But not any technical limitations.

Fig. 3 is a view showing the structure of an embodiment of the planar transformer of the present invention. As shown, a planar transformer 1 using a planar coil of the present invention can include the planar coil 100, at least a second coil 200, and a core 300. The planar coil 100 is overlapped with the second coil 200. The core 300 extends in a direction perpendicular to the plane in which the two coils 100, 200 are located, and passes through a central portion of the two coils 100, 200. The planar transformer 1 further includes a metal casing, including an upper casing 410 and a lower casing 420 covering the core 300 and the coil portions of the two coils 100, 200. In addition to protecting the transformer 1, the housing provides the function of an electromagnetic wave barrier. The second coil 200 can Made of any material with good electrical conductivity. Its structure and shape are not limited. In a preferred embodiment of the invention, the second coil 200 has the same or similar structure as the planar coil 100 of the present invention, but has a different total number of layers/windings to achieve the desired function of the transformer. In an application, if the planar coil 100 is a primary coil, the second coil 200 is a secondary coil. vice versa. The number of the planar coil 100 or the second coil 200 and the number of layers and the number of turns are not limited.

The material, shape and size of the core 300 can be selected from known techniques depending on the application requirements. The materials, shapes and dimensions of the upper and lower casings 410, 420 can also be selected from known techniques depending on the application requirements. Further, the housing is not limited to the manner in which the lower housings are combined. It is also possible to make the housing from a single material or to combine more than two components. If necessary, the housing of one of the sides or the number of layers of one of the housings may be omitted. All of these are within the scope of known technology and need not be described here.

In the structure shown in Fig. 3, the planar coil 100 and the second coil 200 are stacked on each other. However, this example is not a technical limitation. In some examples of the invention, the second coil 200 is a planar coil of the present invention and the layers, or portions, of the two sets of planar coils 100, 200 are interspersed with each other.

10‧‧‧First scroll coil layer

11‧‧‧ pads

20‧‧‧Second scroll coil layer

21‧‧‧ pads

30‧‧‧Second layer coil

40‧‧‧ third layer coil

100‧‧‧ planar coil

Claims (16)

A planar coil of a planar transformer comprising: a continuous material formed in a low temperature deformation manner: a first scroll coil layer, a second scroll coil layer, and N spiral coil layers in series, the first and second Laminating with the N scroll coils such that the outer peripheral surface of the scroll forms a substantially curved surface on the side surface, and the inner peripheral surface of the scroll forms a substantial curved surface on the side surface; wherein N is a double number other than 0; a connecting portion of any two scroll coil layers is connected to a plane in which the two coil layers are located, and a projection position of each connecting portion on a plane of the second scroll coil is distributed in the first scroll coil layer to the second scroll coil Within the projection range of the plane; wherein each coil layer includes the same number of majority loop windings, and includes at least one outer circumference and one inner circumference. The planar coil of claim 1, wherein the first or second scroll coil layer further comprises an extended pad. For example, the planar coil of claim 1 or 2 includes an insulating spacer positioned between any two scroll coil layers. The planar coil of claim 3, wherein the insulating spacer forms a port for the connection portion to be inserted. The planar coil of claim 1 or 2, wherein the winding of each coil layer An electrical insulating material covering the winding material is included. The planar coil of claim 1 or 2, wherein at least one of the adjacent two coil layers is provided on a bottom plate which is an electrically insulating sheet material. A planar transformer comprising the planar coil of claim 1 or 2, at least a second coil, and a core; wherein the planar coil is overlapped with the second coil, the core being perpendicular to a plane of the two coils The direction extends and passes through the central portion of the two coils. The planar transformer of claim 7, further comprising a metal casing covering the core and the coil portion of the two coils. The planar transformer of claim 7, wherein the winding of each coil layer of the planar coil comprises an electrically insulating material covering the winding material. The planar transformer of claim 7, wherein at least one of the adjacent two coil layers of the planar coil is provided on a bottom plate, the bottom plate being an electrically insulating sheet material. The planar transformer of claim 7, wherein the second coil is a planar coil as in claim 1 of the patent application. A planar transformer comprising a planar coil of claim 1 or 2, to a second coil, and a core; wherein the planar coil and a portion of each layer of the second coil are interspersed with each other, the core extending in a direction perpendicular to a plane of the two coils, and passing through the two coils Central part. The planar transformer of claim 12, further comprising a metal casing covering the core and the coil portion of the two coils. The planar transformer of claim 12, wherein the winding of each coil layer of the planar coil comprises an electrically insulating material covering the winding material. The planar transformer of claim 12, wherein at least one of the adjacent two coil layers of the planar coil is provided on a bottom plate, the bottom plate being an electrically insulating sheet material. The planar transformer of claim 12, wherein the second coil is a planar coil as in claim 1 of the patent application.