JPH053123A - Thin coil - Google Patents

Abstract

PURPOSE:To obtain a thin coil, which can be constituted without using a complicated process such as soldering, suitable as the part for a high density mounting circuit device and having an excellently thinned off form and an excellent function and reliability. CONSTITUTION:The title thin coil is provided with at least a flat coil 4, which will be arranged laminatingly, and a thermoplastic resin layer 5 with which the flat winding coils 4 are supported or interlayer-connected. The flat winding coils 4 are insulated with each other, and they are charactistically formed into one body by the heat-bonding of the thermoplastic resin layer 5. Besides, if necessary, input output lead parts 6a and 6b and terminal parts 7a and 7b are led out by insulating with each other to the part in the vicinity of the edge part along the surface of the interlayer insulating thermoplastic resin layer 5 from the flat winding coil 4. Also, they are formed in one body by the heat-bonding of the thermoplastic resin layer 5, and at the same time, the terminal parts 7a and 7b are characteristically connected through a through hole utilizing the plastic deformation of thermoplastic resin.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thin coil suitable for a high density mounting electronic circuit device or the like.

[0002]

2. Description of the Related Art In the trend of making electronic devices lighter, thinner, smaller and smaller,
From the viewpoint of making the circuit configuration compact, attention has been paid to miniaturization and multi-functionalization of the circuit board and mounting components to be configured. For example, in the case of circuit boards, the wiring becomes multi-layered, thin, and highly reliable, and even in the case of flat type coils mounted on the circuit board as inductance elements, the number of wire diameters
Attempts have been made to reduce the thickness of the plane, reduce the size, increase the functionality, and increase the added value, by using the wires that are 10 μm thin wires coated with insulation.

FIG. 8 is a cross-sectional view showing a conventional thin coil having a reduced size or a higher function, where 1 is a diameter, for example.
A flat coil formed by winding an insulated conductor of 40 μm, 2a is an insulating layer such as insulating paper interposed between the laminated flat coils 1, and 3 is laminated via an insulating layer 2b such as insulating paper. Further, it is a magnetic body or a ferrite core arranged outside the planar coil 1.

In addition to the above-mentioned means for forming a flat coil by winding the insulated conductive wire, an etching means or a thin film sputtering means is used to form a desired coil on the insulating film surface, or a copper foil is insulated. After winding and wrapping,
A slice coil having a thinly cut structure has also been proposed.

[0005]

However, the laminated planar coil having the above structure has the following disadvantages. That is, as described above, in the structure of the laminated planar coil, the thin and multilayered planar coil 1 is formed by reducing the diameter of the insulating wire forming the laminated planar coil 1 (about 100 μm at most). Insulating layers 2a and 2b such as insulating paper or insulating resin film must be interposed in order to ensure sufficient insulation, and also the lead-out holes for the individual input / output lead parts drawn out from both ends of each planar coil 1 To
It is also necessary to perforate the insulating layer 2a. In addition, it is necessary to securely solder the drawn thin input / output lead portion (which inevitably has a small diameter to several tens of μm at most) to the required input / output terminal portion. Soldering the output leads is a fairly difficult task. In addition, since the input / output terminal portions inside the planar coils 1 that are laminated and insulated from each other are configured to be pulled out to the outside across the planar coils 1, they are finally configured accordingly. Therefore, the thickness of the laminated planar coil is increased. Therefore, there are problems that not only the manufacturing or configuration process becomes complicated, but also the overall thinning and connection reliability cannot be sufficiently achieved.

The present invention has been made in consideration of the above circumstances, and can be constructed without complicated steps such as soldering, and is excellent in thinning and functional reliability. An object of the present invention is to provide a thin coil suitable as a component for a densely mounted circuit device.

[0007]

A thin coil according to the present invention comprises at least one flat type winding coil arranged in a laminated manner and a thermoplastic resin layer for supporting or insulating the flat type winding coil. And the flat winding coil is insulated from each other and integrated by thermal welding of a thermoplastic resin layer. It is characterized in that the input / output lead portion and the terminal portion are led out by being insulated from each other to the vicinity of the edge portion along the surface of the plastic resin layer, and are integrated by thermal welding of the thermoplastic resin layer. In this configuration, the input / output lead portions and the terminal portions are formed by printing a conductive paste using a thermoplastic resin as a binder, and the input / output terminal portions include a thermoplastic resin layer and a conductive paste that are interlayer-insulated from each other. Through holes are connected by plastic deformation.

Alternatively, at least one flat type winding coil arranged in a laminated manner, a thermoplastic resin layer for supporting or insulating the flat type winding coil from each other, and both outside main coils of the flat type winding coil. A magnetic layer laminated / disposed on the surface through an insulating layer, and a thermoplastic resin layer for interlayer insulation from the planar winding coil. A lead wire portion and a terminal portion, wherein the planar winding coil, the magnetic layer, the input / output lead portion, and the terminal portion terminal portion are insulated from each other,
And characterized by being integrally formed by thermal welding of a thermoplastic resin layer, if required in this configuration, the input and output lead portion and the terminal portion is formed by printing a conductive paste using a thermoplastic resin as a binder, Further, the input / output terminal portions are connected to each other through holes by plastic deformation of a thermoplastic resin layer and an electrically conductive paste that provide interlayer insulation.

[0009]

As described above, in the thin coil according to the present invention, the thermoplastic resin layer is provided for supporting each flat type winding coil or for insulating the layers, and the input / output drawn from both ends of each flat type coil 1 is arranged. The terminals are led out to the vicinity of the edge along the surface of the thermoplastic resin layer and connected by through holes by pressure bonding. Moreover, since each planar coil, the magnetic layer, the input / output lead portion and the terminal portion are closely integrated by the plastic deformation and heat welding of the thermoplastic resin layer such as the interlayer insulation, the flatness and thinness can be achieved. It is possible to improve the functional reliability.

[0010]

Embodiments of the present invention will be described below with reference to FIGS.

Example 1 FIG. 1 is a cross-sectional view showing an example of the structure of a thin coil according to the present invention, in which 4 is formed by winding 100 times an insulating coated conductor wire (insulating film thickness 5 μm) having a diameter of 40 μm. And a thermoplastic resin layer 5 made of, for example, a polycarbonate film having a thickness of 50 μm. Also, 6a, 6b
Are input / output lead portions drawn out from both ends of the planar winding coil 4, and 7a and 7b are terminal portions connected to the input / output lead portions 6a and 6b. Thus, the thin coil having the above-described structure is configured such that the input / output lead portions 6a, 6a, 6 are formed on the predetermined surface of the polycarbonate film 5 by screen-printing, for example, a conductive paste having a thermoplastic resin as a binder.
b and the terminal portions 7a and 7b are formed, the flat type winding coil 4 having the above-mentioned configuration is prepared, and after the flat type winding coil 4 is mounted and arranged on a predetermined area surface of the polycarbonate film 5, It can be produced by hot press molding with a hot press. In the heating and pressure molding step, the thermoplastic resin layer 5 on which the flat type winding coil 4 is mounted and arranged is softened, melted or plastically deformed, and the main surface side of the flat type winding coil 4 is The input / output lead portions 6a and 6b and the terminal portions 7a and 7b are integrally embedded and supported. FIG. 2 shows another example of the configuration of a thin coil. The flat type winding coil 4, the input / output lead portions 6a and 6b, and the terminal portion.
7a and 7b, each of which is arranged on the 5th surface of the polycarbonate film, is shown in a cross-sectional structure in which a plurality of layers are laminated, and is basically manufactured according to the above means. In the case of this laminated structure, the terminal portions 7a, 7b of the input / output lead portions 6a, 6b led out from the respective winding coils 4 are made of a thermoplastic resin layer 5 which forms a support or an interlayer insulating layer in the heat and pressure molding process. Also, through-hole connection is made by plastic deformation of the binder (thermoplastic resin) of the conductive paste, or by a conduction pin or the like. Example 2 FIG. 3 is a cross-sectional view showing still another configuration example of the thin coil according to the present invention, in which 4 is a flat type coil having an outer diameter of 20 mm formed by winding a conductor wire having a diameter of 40 μm, A plurality of planar coils 4 are arranged in a laminated manner. Reference numeral 5 denotes a thermoplastic resin layer which is interposed between the plane type winding coil 4 layers and provides interlayer insulation, for example, a polyether sulfone resin film having a film thickness of 50 μm.
The terminal portions 7a, 7b connected to the input / output lead portions 6a, 6b drawn out from both terminals are formed by, for example, screen-printing a conductive paste on a surface near a predetermined edge portion, and further these terminal portions 7a, Reference numeral 7b is a through hole connection made of a thermoplastic resin layer 5 which insulates the layers from each other. Further, 8 is laminated in layers on both outer main surfaces of the laminated body composed of the respective flat type winding coils 4 and the thermoplastic resin layer 5 for interlayer insulation, with the thermoplastic resin layer 5a as the second interlayer insulation interposed therebetween. It is a ferrite core arranged. Then, each of the planar winding coils 4 and the ferrite core (magnetic material) 8
And terminal portions 7a and 7b including the input / output lead 2 portions 6a and 6b
Has a structure integrated by heat welding the thermoplastic resin layers 5 and 5a for interlayer insulation at the time of heat and pressure molding.

Next, a method of manufacturing the thin coil having the above structure will be described.

For example, a polyether sulfone resin film 5 having a film thickness of 50 μm is prepared, and through holes 9a and 9b for connection are formed in predetermined areas of the polyether sulfone resin film 5, while a thermoplastic resin is used as a binder. Screen printing the conductive paste with
Form a and 7b. Terminals 7a, 7b made of this conductive paste
In the case of the printing formation, the conductive paste may be used to fill the through holes 9a and 9b for connection. Next, a flat coil 4 having an outer diameter of 20 mm, which was prepared by winding a conductor wire having a diameter of 40 μm, was attached to each surface of the polyether sulfone resin film 5 on which the terminal portions 7a, 7b were formed. Type coil 4 input / output lead
6a, 6b Position the tips so that they are aligned. At this time, if the tip portions of the input / output leads 6a and 6b are covered with an insulating film, the insulating film is appropriately deleted. FIG. 4 is a plan view showing this state.

After stacking (laminating) the required number of polyether sulfone resin films 5 on which the respective planar coils 4 are arranged in this manner, a ferrite is further added through the polyether sulfone resin film 5 or the polyether sulfone resin film 5a. The core (magnetic material) 8 is arranged to form a laminated body. FIG. 5 is a cross-sectional view showing this state. If necessary, an insulating resin film, for example, a polyether sulfone resin film is laminated and arranged on the surface of the ferrite core (magnetic material) 8. Then, the laminated body is heated and pressed at 250 ° C. and about 30 kg / cm ² to be integrated with each other to easily form a flat type thin coil having a structure shown in cross section in FIG. Obtainable. That is, by the heat and pressure molding, the thermoplastic resin layers are melted or plastically deformed to be welded and integrated with each other, and the extracted input / output lead portions 6a, 6b have the tips contacting the input / output terminal portions 7a, Pressed against surface 7b (no soldering required) to make the required electrical connection. On the other hand, in the heating and pressure molding step, the corresponding input / output terminal portions 7a, 7b to which the input / output lead portions 6a, 6b are connected are formed by the conductive paste forming the same and the plastic deformation of the thermoplastic resin layer forming the interlayer insulation. Ensures a through-hole connection.

Although a polyether sulfone resin film is used as the thermoplastic resin layer in the above, for example, a polysulfone resin film, a polyether-ether ketone resin film, a polyether-imide resin film, a polyphenyl sulfide resin film, a polycarbonate. A resin film or the like may be used. The planar coil body is not limited to the wire wound type, and may be, for example, a vapor deposition thin film type, a type obtained by etching copper foil, or a printed type using a conductive paste. And the like, which is preferable. In addition, the input / output leads 5a and 5b drawn from both ends of the planar winding coil are
Similar to the formation of the terminal portion, it may be formed by a printing method using a conductive paste. Furthermore, the through-hole connection of the terminal portion may be performed by means such as insertion of a lead pin, but using a conductive paste as illustrated above,
It is simpler and more reliable to use the plastic deformation of the thermoplastic resin at the time of integration by heat and pressure molding.

Embodiment 3 FIG. 6 is a sectional view showing still another configuration example of the thin coil according to the present invention, in which 4 is a flat type coil having an outer diameter of 12 mm, which is constructed by winding a conductor wire having a diameter of 40 μm. Thus, a plurality of planar coils 4 are arranged in a laminated manner. Reference numeral 5 denotes a thermoplastic resin layer which is interposed between the plane type winding coil 4 layers and provides interlayer insulation, for example, a polycarbonate resin film having a film thickness of 60 to 100 μm.
The terminal portions 7a, 7b connected to the input / output leads 6a, 6b drawn from both terminals of are formed by, for example, screen-printing a conductive paste on a surface near a predetermined edge portion,
Further, these terminal portions 7a, 7b are connected through holes by a thermoplastic resin layer 5 which insulates each other. Then,
The terminal portions 7a, 7b including the respective flat type winding coils 4 and the input / output leads 6a, 6b are integrated by thermal welding of a thermoplastic resin layer 5 for interlayer insulation during heat and pressure molding. is doing.

The thin coil having such a structure is
It can be manufactured as follows. For example, a polycarbonate resin film 5 having a film thickness of 80 μm is prepared, and through holes 9a and 9b for connection are formed in predetermined areas of the polycarbonate resin film 5, respectively, while a conductive paste using a thermoplastic resin as a binder is screen-printed. Then, the input / output lead portions 6a, 6b and the input / output terminal portions 7a, 7b are formed. Next, the flat type coil 4 having an outer diameter of 12 mm, which was prepared by winding a conductor wire having a diameter of 40 μm, was attached to the terminal portion 7
Polycarbonate resin film 5 with a, 7b etc. formed
The ends of each planar coil 4 are aligned with the input / output lead portions 6a, 6b on the surface. At this time, if the tip of the end of the planar coil 4 is covered with an insulating film, the insulating film is appropriately deleted. After stacking (laminating) a required number of the polycarbonate resin films 5 on which the respective planar coils 4 are arranged in this manner, the polycarbonate resin films 5 are arranged to form a laminated body. FIG. 7 is a sectional view showing this state. After that, the laminated body is, for example, 250 ° C.,
By heating and press-molding at about 30 kg / cm ² , it is possible to easily obtain the flat type thin coil having the structure shown in the sectional view of FIG. 6 integrated with each other. That is, the thermoplastic resin layer is melted or plastically deformed by the above-mentioned heat and pressure molding to be fused and integrated with each other, and the extracted input / output lead portions 6a, 6b and the connected input / output terminal portions 7a, 7
While b is also pressed and embedded in the thermoplastic resin layer, the input / output terminal portions 7a and 7b form a so-called through-hole connection due to plastic deformation of the thermoplastic resin layer which also insulates the layers.

In this structure, a magnetic material may be arranged on the outer surface via an insulating layer.

[0019]

As described above, the thin coil according to the present invention uses the thermoplastic resin as the interlayer insulation, and makes good use of the plastic deformation of the thermoplastic resin. For this reason, the structure is densified (no void, etc.) as a whole, and has a thin or compact structure. Moreover, the input / output lead portion and the terminal portion of each planar coil are not only integrated by being embedded in the interlayer insulating layer by the plastic deformation of the thermoplastic resin, but also the input / output terminal portion can be easily and securely formed. Is connected to the through hole. Therefore, the complexity of the configuration can be avoided, and the compactness and the reliability of the connection can be improved. Thus, the thin coil according to the present invention is easy to handle because it is firmly integrated as a whole, and has high functional reliability due to being densified as a whole. For example, it can be said that it is suitable as a component for a mounted circuit.

[Brief description of drawings]

FIG. 1 is a sectional view showing a configuration example of a thin coil according to the present invention.

FIG. 2 is a cross-sectional view showing another configuration example of the thin coil according to the present invention.

FIG. 3 is a cross-sectional view showing still another configuration example of the thin coil according to the present invention.

FIG. 4 is a plan view schematically showing an example of a manufacturing process of a thin coil according to the present invention, showing a state in which a planar coil is arranged on a thermoplastic resin film (layer) provided with a terminal portion.

FIG. 5 is a cross-sectional view schematically showing an example of a manufacturing process of a thin coil according to the present invention, showing a state in which respective constituent members are laminated.

FIG. 6 is a cross-sectional view showing still another configuration example of the thin coil according to the present invention.

FIG. 7 is a cross-sectional view schematically showing another example of the manufacturing process of the thin coil according to the present invention, showing a state in which the respective constituent members are laminated.

FIG. 8 is a cross-sectional view showing the structure of a conventional thin coil.

[Explanation of symbols]

1, 4 ... Planar coil 3, 8 ... Ferrite core
5, 5a ... Thermoplastic resin layer (insulating support layer) 6a, 6b
… I / O lead parts 7a, 7b… I / O terminal parts 9a, 9b… Through holes

Claims (6)

[Claims] 1. A flat-type winding coil, comprising: at least one flat-type winding coil arranged in a stack; and a thermoplastic resin layer that supports or interlayer-insulates the flat-type winding coil. A thin coil characterized by being integrated with a thermoplastic resin layer by heat-sealing the thermoplastic resin layer. 2. At least one planar winding coil arranged in a stack, a thermoplastic resin layer for supporting or insulating the planar winding coil from each other, and interlayer insulation from the planar winding coil. An input / output lead portion led out to the vicinity of the edge along the surface of the thermoplastic resin layer, wherein the planar winding coil and the input / output lead portion are insulated from each other, and by thermal welding of the thermoplastic resin layer. A thin coil characterized by being integrated. 3. The input / output lead portion and the input / output terminal portion according to claim 2, wherein the input / output terminal portion is formed by printing a conductive paste using a thermoplastic resin as a binder, and the input / output terminal portion is formed of the thermoplastic resin layer and the conductive paste. A thin coil characterized by being through-hole connected by deformation. 4. At least one planar winding coil arranged in a stack, a thermoplastic resin layer for supporting or insulating the planar winding coil from each other, and both outer side main coils of the planar winding coil. A magnetic layer disposed on the surface via an insulating layer,
An input / output terminal portion to which through-hole connection is made between input / output lead portions led out from the planar winding coil along a surface of a thermoplastic resin layer supporting or insulating between layers to a vicinity of an edge portion, A thin coil characterized in that a die winding coil, a magnetic layer, an input / output lead portion and an input / output terminal portion are insulated from each other and integrated by thermal welding of a supporting or interlayer insulating thermoplastic resin layer. 5. The thermoplastic resin layer according to claim 4, wherein each input / output lead portion and input / output terminal portion are formed by printing a conductive paste using a thermoplastic resin as a binder, and the input / output terminal portions are insulated from each other. And a thin coil characterized by being through-hole connected by plastic deformation of a conductive paste. 6. The thin coil according to claim 4 or 5, wherein the magnetic layer is covered with an insulating layer.