JP2022088866A - Electrical connection structure, and connection body of insulation electric wire and printed wiring board - Google Patents

Abstract

To provide an electrical connection structure that has center conductors of a plurality of insulation electric wires easily and securely connected to a plurality of connected parts in one-to-one relation, and a connection body of an insulation electric wire and a printed wiring board.SOLUTION: An electric connection structure according to one aspect of the present disclosure is an electric connection structure of a plurality of center conductors of a plurality of insulation electric wires and a plurality of connected parts, wherein the plurality of center conductors are exposed in axial tip part regions of the plurality of insulation electric wires and overlap with the plurality of connected parts in one-to-one relation. The electric connection structure has a solder connection part for bonding the plurality of exposed center conductors and the plurality of connected parts together, and an adhesive for mutually bonding the plurality of exposed center conductors for positioning, and the adhesive is bonded to side faces of the plurality of exposed center conductors, and arranged in a direction perpendicular to the axial direction.SELECTED DRAWING: Figure 6

Description

The present disclosure relates to electrical connection methods and connectors for insulated wires and printed wiring boards.

When electrically connecting a printed wiring board or the like of a small electronic device, a plurality of insulated wires such as a coaxial cable may be used. In recent years, with the further miniaturization of electronic devices, the line width and spacing of a plurality of wirings arranged on a substrate in a printed wiring board have become smaller. Along with this, the diameter and spacing of the plurality of insulated wires connected to the plurality of wirings are also reduced.

As such an electrical connection structure, a structure in which the central conductors of a plurality of insulated wires are electrically connected to a plurality of wirings of a printed wiring board in a state of being aligned and arranged in a plurality of arrangement grooves of a flexible insulating sheet is proposed. (See Japanese Patent Application Laid-Open No. 2010-118318).

Japanese Unexamined Patent Publication No. 2010-118318

In the electrical connection structure as described in the above patent document, since it is necessary to form a plurality of arrangement grooves in the flexible insulating sheet, the structure becomes complicated and it is difficult to say that it is easy to manufacture. Moreover, it is difficult or time-consuming to match the cross-sectional shape of each array groove with the cross-sectional shape of each central conductor, and it is difficult to say that it is easy to manufacture in this respect as well.

Further, since the dimensions of the flexible insulating sheet increase in the height direction by the depth of these arrangement grooves, the thickness of the connection body of the insulated wire and the printed wiring board may increase.

In addition, as described above, it is difficult to match the cross-sectional shape of each array groove with the cross-sectional shape of each central conductor, so that these connections may be insufficient.

Therefore, an electrical connection structure in which the central conductors of a plurality of insulated wires are easily and reliably connected to a plurality of connected portions in a one-to-one correspondence relationship without increasing the thickness of the connecting body, as well as the insulated wires and printed wiring. The subject is to provide a board connector.

The electrical connection structure according to one aspect of the present disclosure made to solve the above problems includes a plurality of central conductors in a plurality of insulated wires having an insulating layer covering the central conductor and the peripheral surface of the central conductor, and a plurality of central conductors. In the electrical connection structure with the connected portion of the above, the plurality of central conductors are exposed in the axial tip region of the plurality of insulated wires, and are superimposed on the plurality of connected portions in a one-to-one correspondence relationship. The adhesive comprises a solder connection portion for adhering the exposed plurality of center conductors and the plurality of connected portions, and an adhesive for adhering the exposed plurality of center conductors to each other for positioning. Is adhered to the side surface of the plurality of exposed center conductors and is arranged along the direction perpendicular to the axial direction.

The connection body of the insulated wire and the printed wiring board according to another aspect of the present disclosure made in order to solve the above-mentioned problems has the said electrical connection structure, and the plurality of connected portions are the substrate and the surface of the substrate. The above-mentioned plurality of wirings in a printed wiring board having a plurality of wirings laminated on the above.

In the electrical connection structure of the present disclosure, the central conductors of a plurality of insulated wires are easily and surely connected to a plurality of connected portions in a one-to-one correspondence relationship without increasing the thickness of the connecting body. In the connection body of the insulated wire and the printed wiring board of the present disclosure, the central conductors of the plurality of insulated wires are easily and surely connected to the plurality of connected portions in a one-to-one correspondence without increasing the thickness of the connecting body. Will be done.

FIG. 1 is a schematic plan view showing an electrical connection structure in a connection body of an insulated wire and a printed wiring board according to the first embodiment. FIG. 2 is a schematic partially enlarged plan view showing a part of the connection body of FIG. 1 in an enlarged manner. FIG. 3 is a cross-sectional view taken along the line DD of FIG. FIG. 4 is a cross-sectional view taken along the line EE of FIG. FIG. 5 is a cross-sectional view taken along the line AA of FIG. FIG. 6 is a cross-sectional view taken along the line CC of FIG. FIG. 7 is a cross-sectional view taken along the line BB of FIG. FIG. 8 is a schematic partial plan view showing a method of manufacturing the electrical connection structure of the present embodiment. FIG. 9 is a schematic partial plan view showing a method of manufacturing the electrical connection structure of the present embodiment. FIG. 10 is a schematic partial plan view showing a method of manufacturing the electrical connection structure of the present embodiment. FIG. 11 is a schematic partial plan view showing a method of manufacturing the electrical connection structure of the present embodiment. FIG. 12 is a schematic partial plan view showing a method of manufacturing the electrical connection structure of the present embodiment. FIG. 13 is a schematic partial plan view showing a method of manufacturing the electrical connection structure of the present embodiment. FIG. 14 is a schematic partial front view showing a method of manufacturing the electrical connection structure of the present embodiment. FIG. 15 is a schematic partial front view showing a method of manufacturing the electrical connection structure of the present embodiment. FIG. 16 is a schematic partial front view showing a method of manufacturing the electrical connection structure of the present embodiment. FIG. 17 is a schematic partial plan view showing a method of manufacturing the electrical connection structure of the present embodiment. FIG. 18 is a schematic partially enlarged plan view showing a part of the connection body of the insulated wire and the printed wiring board of the second embodiment in an enlarged manner. FIG. 19 is a cross-sectional view taken along the line FF of FIG. FIG. 20 is a cross-sectional view taken along the line GG of FIG. FIG. 21 is a schematic partially enlarged plan view showing the electrical connection structure of another embodiment in the same manner as in FIGS. 2 and 18.

[Explanation of Embodiments of the present disclosure]
The electrical connection structure according to one aspect of the present disclosure is an electrical connection between a plurality of central conductors in a plurality of insulated wires having an insulating layer covering the central conductor and the peripheral surface of the central conductor, and a plurality of connected portions. In the structure, the plurality of central conductors are exposed in the axial tip region of the plurality of insulated wires, and are superposed on the plurality of connected portions in a one-to-one correspondence relationship, and the plurality of exposed centers are overlapped. A solder connection portion for adhering between a conductor and a plurality of connected portions and an adhesive for adhering the exposed plurality of center conductors to each other for positioning are provided, and the adhesive comprises the exposed plurality of center conductors. It is adhered to the side surface of the above and is arranged along the direction perpendicular to the axial direction.

Since the electrical connection structure can hold the exposed center conductors of the plurality of insulated wires at intervals corresponding to the plurality of connected portions by the adhesive, the plurality of exposed center conductors can be simultaneously held at the same time. It can be reliably arranged on a plurality of connected portions. Furthermore, since a flexible insulating sheet having an arrangement groove as described in Patent Document 1 is not used, it is easy to manufacture and it is possible to suppress an increase in the thickness of the connecting body. In addition, the presence of the adhesive on the sides of the exposed center conductors more reliably secures these center conductors. Therefore, in the electrical connection structure, the central conductors of the plurality of insulated wires are easily and surely connected to the plurality of connected portions in a one-to-one correspondence relationship without increasing the thickness of the connecting body.

The adhesive may be further adhered to the top surfaces of the exposed plurality of central conductors.

By further adhering the adhesive to the upper surface of the plurality of exposed center conductors, the plurality of exposed center conductors can be more reliably held at intervals corresponding to the plurality of connected portions.

It is preferable that the adhesive has transparency.

Since the adhesive has transparency, the presence of the central conductor can be confirmed through the adhesive, so that the electrical connection structure is more excellent in manufacturability.

It is preferable that the adhesive is arranged on the insulating layer side of the axial tip edges of the exposed plurality of central conductors.

By arranging the adhesive in this way, the amount of the adhesive present in the overlapped portion between the exposed central conductor and the plurality of connected portions can be reduced, so that the exposed plurality of adhesives can be reduced. It becomes easy to solder the center conductor and the plurality of connected portions. Therefore, it becomes easier to manufacture the electrical connection structure. In addition, by arranging the adhesive as described above, the soldering state of the central conductor to the connected portion can be easily confirmed, so that the connection between the central conductor and the connected portion is more reliable. become.

It is preferable that the adhesive is arranged so as to straddle the exposed central conductor and the plurality of insulating layers.

By arranging the adhesive in this way, the boundary between the exposed portion and the portion covered with the insulating layer in the plurality of central conductors is protected by the adhesive, and thus the plurality of the above boundaries. It is possible to suppress disconnection of the center conductor.

It is preferable that the adhesive is arranged so as to overlap the connecting portions of the exposed central conductor and the plurality of connected portions.

By arranging the adhesive in this way, the portions of the plurality of central conductors connected to the plurality of connected portions are fixed by the adhesive, so that the plurality of center conductors and the plurality of wirings are fixed. When superimposing, the alignment accuracy can be further improved. In addition, since the plurality of center conductors and the plurality of connected portions can be soldered near the portions of the plurality of center conductors fixed by the adhesive, misalignment during soldering is reduced. can do.

It is preferable that the electrical connection structure further comprises a synthetic resin base film that is adhered to the exposed central conductors via the adhesive and is arranged perpendicular to the axial direction.

By further including the base film in the electrical connection structure, the adhesive is reinforced, so that the plurality of exposed center conductors are more reliably fixed. Therefore, it becomes easier to manufacture the electrical connection structure.

It is preferable that the base film has transparency.

Since the base film has transparency, it is possible to visually recognize the inside (connected portion side) of the base film. That is, it becomes possible to visually recognize the fixed state of the plurality of exposed central conductors by the adhesive through the base film. Therefore, it becomes easier to manufacture the electrical connection structure.

The connection body of the insulated wire and the printed wiring board according to another aspect of the present disclosure includes the electrical connection structure, and the plurality of connected portions have a substrate and a plurality of wirings laminated on the surface of the substrate. These are the plurality of wirings in the printed wiring board.

Since the connection body of the insulated wire and the printed wiring board has the electrical connection structure, the central conductors of the plurality of insulated wires are connected to the plurality of wirings one-to-one without increasing the thickness of the connecting body, as described above. It is easily and securely connected in a correspondence relationship.

Here, the axial direction and "perpendicular" are not limited to those that are exactly 90 ° with respect to the axial direction, and mean that they have an angle of 80 ° or more and 100 ° or less. The "tip" side means the side of the insulated wire towards the end of the side connected to the connected portion.

[Details of Embodiments of the present disclosure]
Hereinafter, the electrical connection structure according to the present disclosure and the embodiment of the connection body of the insulated wire and the printed wiring board will be described in detail with reference to the drawings.

[First Embodiment]
[Electrical connection structure and connection body]
As shown in FIGS. 1 to 7, the electrical connection structure of the present embodiment is a structure of a connection portion of a connection body of the insulated wire 1 and the printed wiring board 10, and a plurality of insulated wires 1 are connected to the printed wiring board 10. Arranged. In the following, the side of the insulated wire 1 away from the printed wiring board 10 in the axial direction is referred to as the "rear end" side.

The electrical connection structure of the present embodiment is arranged on a plurality of central conductors 4 in a plurality of insulated wires 1 having an insulating layer 5 covering the central conductor 4 and the peripheral surface of the central conductor 4, and a printed wiring board 10. It is an electrical connection structure with a plurality of wirings (connected portions) 12.

The plurality of central conductors 4 are exposed in the axial tip region of the plurality of insulated wires 1, and are overlapped with the tip portions of the plurality of wirings 12 in a one-to-one correspondence relationship. In the electrical connection structure, the plurality of solder connection portions 50 for adhering between the plurality of exposed center conductors 4 and the plurality of wirings 12 and the plurality of exposed center conductors 4 are adhered to each other for positioning. The adhesive 30 is provided with the agent 30, and the adhesive 30 is adhered to the side surface of the plurality of exposed central conductors 4 and is arranged along the direction perpendicular to the axial direction.

In the present embodiment, the insulated wire 1 further includes an outer conductor 6 arranged around the insulating layer 5 and an outer cover 7 covering the periphery of the outer conductor 6 in addition to the central conductor 4 and the insulating layer 5. Examples of such an insulated wire 1 include a coaxial cable.

In the present embodiment, the printed wiring board 10 further includes a ground wire (here, one ground wire) 14 that is electrically connected to the outer conductors 6 of the plurality of insulated wires 1.

In the present embodiment, the electrical connection structure further includes a base film 40 made of synthetic resin, which is adhered to a plurality of wirings 12 via an adhesive 30.

<Insulated wire>
The plurality of insulated wires 1 are arranged side by side. More specifically, the plurality of insulated wires 1 are arranged in a stripe shape. Here, "striped" means a state of being substantially parallel and evenly spaced in the same plane, and "substantially parallel" means that the angle formed by the central axis is within ± 10 °. do.

As shown in FIG. 3, each insulated wire 1 includes a central conductor 4, an insulating layer 5 covering the peripheral surface of the central conductor 4, an external conductor 6 arranged around the insulating layer 5, and the outside thereof. It has an outer cover 7 that covers the conductor 6. The central conductor 4, the insulating layer 5, and the outer conductor 6 are exposed in this order from the tip edge in the axial tip region of each insulated wire 1. FIG. 1 illustrates an embodiment in which 32 insulated wires 1 are used, but the number of insulated wires 1 is not particularly limited.

(Center conductor)
The center conductor 4 is not particularly limited, and for example, a metal wire such as copper, a copper alloy, aluminum, or an aluminum alloy can be used. Further, such a metal wire may be a single wire or a stranded wire. The number of strands in the case of a stranded wire is not particularly limited, but is, for example, 2 or more and 30 or less. FIG. 3 illustrates an embodiment in which the central conductor 4 is made by twisting three strands.

The cross-sectional shape of the metal wire forming the central conductor 4 is not particularly limited, and various shapes such as a circle, a square, and a rectangle can be adopted. However, the electrical connection structure is a round wire having a circular cross-sectional shape. Is preferably used.

The lower limit of the average diameter of the center conductor 4 is preferably 10 μm, more preferably 15 μm. On the other hand, the upper limit of the average diameter of the central conductor 4 is preferably 500 μm, more preferably 200 μm. If the average diameter of the center conductor 4 is less than the above lower limit, the center conductor 4 may be easily broken. Further, when the average diameter of the central conductor 4 exceeds the above upper limit, the electrical connection structure may become unnecessarily large.

The average exposure length of the center conductor 4 from the insulating layer 5 is, for example, 0.2 mm or more and 3.0 mm or less.

In the embodiment shown in FIG. 4, the central conductor 4 exposed from each insulating layer 5 is covered with the first preliminary solder portion 51 described later.

(Insulation layer)
The insulating layer 5 is laminated on the peripheral surface of the central conductor 4 so as to cover the central conductor 4. The insulating layer 5 may be a single layer or a multilayer structure having two or more layers.

The material of the insulating layer 5 is not particularly limited as long as it has insulating properties and flexibility. For example, polyethylene, an ethylene resin such as an ethylene vinyl acetate copolymer, an ethyl ethylene acrylate copolymer, an ethylene resin, and polypropylene are used. , Polyethylene propylene rubber, resin blended with polyolefin such as styrene elastoma, polyimide, polyamideimide, polyesterimide, silane crosslinkable resin composition, PTFE (polytetrafluoroethylene), PFA (perfluoroalkoxyalkane), FEP (perfluoro) A fluororesin such as (ethylenepropen copolymer) can be used.

The insulating layer 5 is formed on the central conductor 4 by, for example, a method of extruding a molten resin onto the peripheral surface of the central conductor 4 to cure it, a method of applying a paint obtained by dissolving the resin in an organic solvent to the peripheral surface of the central conductor 4, and the like. Can be coated.

The average thickness (thickness) of the insulating layer 5 is not particularly limited, but may be, for example, 3 μm or more and 1 mm or less.

The average exposed length of the insulating layer 5 (that is, the average length between the outer conductor 6 and the central conductor 4) is not particularly limited, and the design of the connected portion (in the present embodiment, the wiring length of the printed wiring board). It can be set as appropriate according to the design value). Depending on the design of the connected portion, the average exposed length of the insulated layer 5 can be, for example, 0.1 mm or more, and can be, for example, 10 mm or less.

The insulating layer 5 may have a primer layer in contact with the central conductor 4. As the primer layer, a cured resin such as ethylene that does not contain a metal hydroxide can be preferably used. By providing such a primer layer, it is possible to prevent the detachability of the insulating layer 5 and the central conductor 4 from deteriorating with time.

(External conductor)
The outer conductor 6 is laminated on the peripheral surface of the insulating layer 5. The outer conductor 6 serves as a ground and functions as a shield for preventing electrical interference from other circuits. The outer conductor 6 covers the peripheral surface of the insulating layer 5. The outer conductor 6 is not particularly limited, and for example, a metal wire such as copper, silver-plated copper, or tin-plated copper alloy can be used. The outer conductor 6 is, for example, a state in which a wire is spirally wound around the outer peripheral surface of the insulating layer 5 by horizontal winding, a state in which a plurality of strands are wound around the outer peripheral surface of the insulating layer 5, and the like.

The cross-sectional shape of the metal wire forming the outer conductor 6 is not particularly limited, and various shapes such as a circle, a square, and a rectangle can be adopted. However, the electrical connection structure is a round wire having a circular cross-sectional shape. Is preferably used.

The lower limit of the average diameter of the metal wire constituting the outer conductor 6 is preferably 10 μm, more preferably 15 μm. The upper limit of the average diameter of the outer conductor 6 is preferably 500 μm, more preferably 200 μm. If the average diameter of the outer conductor 6 is less than the above lower limit, the outer conductor 6 may be easily broken. On the other hand, when the average diameter of the outer conductor 6 exceeds the above upper limit, the electrical connection structure may become unnecessarily large.

The average exposed length of the outer conductor 6 (that is, the average length between the outer cover 7 and the insulating layer 5) can be, for example, 0.1 mm or more and 5 mm or less.

The outer conductor 6 exposed from the outer cover 7 is fixed by the metal fixing portion 20. The fixing portion 20 is arranged vertically in the axial direction. Examples of the fixing portion 20 include a metal plate, solder, and the like. For example, when a pair of metal plates is used as the fixing portion 20, a plurality of exposed outer conductors 6 are fixed by being sandwiched between the pair of metal plates from above and below. For example, when solder is used as the fixing portion 20, a plurality of exposed outer conductors 6 are fixed by being integrated while covering the peripheral surface of each outer conductor 20 with the molten solder. For example, when a metal plate is used as the fixing portion 20, a plurality of exposed outer conductors 6 are joined to the metal plate via molten solder. The plurality of external conductors 6 are electrically connected to the ground wire 14 of the printed wiring board 10 via the fixing portion 20.

(Coat)
The outer cover 7 is arranged so as to cover the outer conductor 6. The outer cover 7 may have a single layer or a multi-layer structure having two or more layers.

The material of the outer cover 7 is not particularly limited as long as it has insulating properties and flexibility, and for example, the same material as the above-mentioned insulating layer 5 or a polyester resin such as PET (polyethylene terephthalate) may be used. Can be done.

The average thickness (thickness) of the outer cover 7 is not particularly limited, but may be, for example, 5 μm or more and 1 mm or less.

<Printed wiring board>
As shown in FIGS. 1, 2, 6 and 7, the printed wiring board 10 has an insulating substrate 11 and a plurality of wirings 12 laminated on the surface of the substrate 11. The central conductors 4 of the plurality of insulated wires 1 are connected to the plurality of wirings 12 by the solder connecting portion 50 in a one-to-one correspondence relationship. The printed wiring board 10 further includes one or more (here, one) ground wires 14 laminated on the surface of the substrate 11.

(substrate)
The substrate 11 of the printed wiring board 10 is composed of a plate-shaped member having an insulating property. The plate-shaped member constituting the substrate 11 may be a rigid substrate or a flexible substrate. Specifically, a resin plate can be used as the rigid substrate. As the material of this resin plate, for example, glass epoxy or the like is preferably used. Specifically, a resin film can be adopted as the flexible substrate having flexibility. As the material of this resin film, for example, polyimide, polyethylene terephthalate and the like are preferably used. The substrate 11 may contain a filler, an additive, or the like.

The average thickness of the substrate 11 is appropriately set according to the design concept and the like. For example, if the average thickness of the substrate 11 is too small, the strength of the substrate 11 may be insufficient. On the other hand, if the average thickness of the substrate 11 is too large, the electrical connection structure may become unnecessarily thick. Therefore, for example, the average thickness of the substrate 11 can be appropriately set in consideration of these points together with the design concept.

(wiring)
The plurality of wirings 12 (more specifically, the tip portions of the plurality of wirings 12) as the plurality of bonded portions are arranged side by side on the substrate 11 while being spaced apart from each other. Specifically, the plurality of wirings 12 are arranged in a stripe shape on the substrate 11. These wirings 12 are formed into a desired planar shape (pattern), for example, by etching a metal layer laminated on the surface of the substrate 11. The plurality of wirings 12 are each formed in a rectangular shape in a plan view and are arranged in a stripe shape.

Each wiring 12 can be formed of a conductive material, but is generally formed of, for example, copper. Further, the surface of the wiring 12 may be plated. That is, the wiring 12 may be covered with the second preliminary solder portion 52. As this plating treatment, tin plating, gold plating or solder plating is preferable.

As the lower limit of the average thickness of the wiring 12, 5 μm is preferable, and 8 μm is more preferable. The upper limit of the average thickness of the wiring 12 is preferably 100 μm, more preferably 50 μm. If the average thickness of the wiring 12 is less than the above lower limit, the continuity may be insufficient. On the other hand, if the average thickness of the wiring 12 exceeds the above upper limit, the electrical connection structure may become unnecessarily thick.

The lower limit of the average width of the wiring 12 is preferably 0.8 times, more preferably 1 times, the average diameter of the center conductor 4 of the insulated wire 1. The upper limit of the average width of the wiring 12 is preferably twice the average diameter of the central conductor 4, more preferably five times, and even more preferably three times. If the average width of the wiring 12 is less than the above lower limit, the connection of the center conductor 4 may not be easy. On the other hand, when the average width of the wiring 12 exceeds the above upper limit, the width of the electrical connection structure may become unnecessarily large.

The average distance between the centers of the adjacent wirings 12 can be, for example, 0.5 times or more and 5 times or less the average diameter of the center conductor 4.

<Adhesive>
As shown in FIGS. 1, 2 and 5 to 7, the adhesive 30 is arranged from the upper surface to the side surface of the plurality of exposed central conductors 4 and is perpendicular to the axial direction of the central conductor 4 (FIG. 1). It is arranged in a band shape along the vertical direction of 1. As described above, the adhesive 30 is further arranged on the upper surface in addition to the side surface of the plurality of exposed center conductors 4. In such a state, the adhesive 30 is adhered to the plurality of center conductors 4. In the present embodiment, the adhesive 30 is adhered to each center conductor 4 via each first preliminary solder portion 51. The adhesive 30 constitutes an adhesive layer. Both ends of the adhesive 30 in the direction perpendicular to the axial direction extend outward from each of the outermost central conductors 4 of the plurality of central conductors 4, and are adhered to the surface of the printed wiring board 10. ing. In the present embodiment, as shown in FIG. 2, the rear end portion (upper end portion in FIG. 2) of the adhesive 30 straddles the tip portions (lower end portion in FIG. 2) of the plurality of insulating layers 5. It is also adhered to the upper surface and the side surface of the insulating layer 5 of the above.

The lower limit of the average width of the adhesive 30 (the average length in the axial direction (vertical direction in FIG. 2) of the central conductor 4) is preferably 100 μm, more preferably 200 μm. The upper limit of the average width of the adhesive 30 is preferably 1500 μm, more preferably 1000 μm. If the average width of the adhesive 30 is less than the above lower limit, the strength of the adhesive 30 becomes insufficient, and there is a risk of breakage before adhering to the printed wiring board 10. On the other hand, if the average width of the adhesive 30 exceeds the above upper limit, the electrical connection structure may become unnecessarily large.

The lower limit of the extension distance of the adhesive 30 from the central conductors 4 located on both outer sides is preferably twice the diameter of the central conductor 4, and more preferably 2.5 times. The upper limit of the extension distance from the central conductor 4 located on both outermost sides is preferably 100 times, more preferably 50 times the diameter of the central conductor 4. When the extension distance of the adhesive 30 is less than the lower limit, the adhesive strength between the extension portion of the adhesive 30 and the printed wiring board 10 becomes insufficient, and the center conductor 4 is wired until soldering is completed. It may not be possible to position it. On the other hand, when the extension distance of the adhesive 30 exceeds the upper limit, the electrical connection structure may become unnecessarily large.

As shown in FIGS. 2 and 7, the adhesive 30 (more specifically, the tip edge of the adhesive 30) is located on the rear end side (insulation layer 5 side) of the exposed center conductor 4 from the tip edge. It is preferable to do so. By arranging the adhesive 30 in this way, it is possible to reduce the amount of the adhesive 30 present in the overlapped portion between the exposed central conductor 4 and the plurality of wirings 12, so that the exposed plurality of adhesives 30 can be reduced. It becomes easy to solder the center conductor 4 and the plurality of wirings 12. Therefore, it becomes easier to manufacture the electrical connection structure. In addition, by arranging the adhesive 30 as described above, the soldering state of the central conductor 4 to the wiring 12 can be easily confirmed, so that the connection between the central conductor 4 and the wiring 12 is more reliable. become.

The lower limit of the distance between the tip edge of the adhesive 30 and the tip edge of the exposed center conductor 4 (that is, the length of the center conductor 4 exposed to the tip side from the adhesive 30) is preferably 10 μm, preferably 20 μm. More preferred. The upper limit of the distance between the tip edge of the adhesive 30 and the tip edges of the plurality of exposed center conductors 4 is preferably 200 μm, more preferably 150 μm. If the distance is less than the lower limit, the ease of directly visually recognizing the tip edge of the center conductor 4 may decrease, and the ease of confirming the connection state between the center conductor 4 and the wiring 12 may decrease. On the other hand, if the distance exceeds the upper limit, the electrical connection structure may become unnecessarily large.

In the present embodiment, as described above, the adhesive 30 is arranged so as to straddle the plurality of exposed center conductors 4 and the plurality of insulating layers 5. By arranging the adhesive 30 in this way, the boundary between the exposed plurality of central conductors 4 and the plurality of insulating layers 5 is protected by the adhesive 30, so that the plurality of center conductors 4 are disconnected at the boundary. Can be suppressed. The lower limit of the average length in the axial direction (vertical direction in FIG. 2) of the portion where the adhesive 30 and the plurality of insulating layers 5 overlap is preferably 10 μm, more preferably 20 μm. The upper limit of the average length of the overlapping portions in the axial direction is preferably 500 μm, more preferably 300 μm. If the average length of the overlapping portions in the axial direction is less than the lower limit, it may be difficult to sufficiently suppress the disconnection of the exposed plurality of central conductors 4 at the boundary. On the other hand, if the average length of the overlapping portions in the axial direction exceeds the upper limit, the electrical connection structure may become unnecessarily large.

For example, in the cross section shown in FIG. 5, the lower limit of the average thickness of the upper surface (the surface in contact with the upper end edge) of the plurality of center conductors 4 in the adhesive 30 is 1/10 of the average diameter of the plurality of center conductors 4. Is preferable, and 1/5 is more preferable. The upper limit of the average thickness of the plurality of center conductors 4 from the upper surface to the upper side in the adhesive 30 is preferably 2/3, more preferably 1/2 of the average diameter of the plurality of center conductors 4. If the average thickness is less than the lower limit, it may be difficult for the adhesive 30 to sufficiently fix the plurality of central conductors 4, and it may be difficult to hold the plurality of insulated wires 1 together. If the average thickness exceeds the upper limit, the electrical connection structure may become unnecessarily thick. When the adhesive 30 is adhered to the central conductor 4 via the first preliminary solder portion 51 as in the present embodiment, the average thickness of the upper side is from the upper surface of the first preliminary solder portion 51 to the upper side. The average thickness. In this embodiment, the mode in which the adhesive 30 is also arranged on the upper surface is shown, but in addition to this, an embodiment in which the adhesive 30 is arranged on the side surface but not on the upper surface can be adopted. In this case, the average thickness of the plurality of central conductors 4 in the adhesive 30 from the upper surface to the upper side is 0.

For example, in the cross section shown in FIG. 5, the size of the region where the adhesive 30 adheres to the side surface of the plurality of central conductors 4, that is, the extent to which the adhesive 30 extends downward from the upper surface of the plurality of central conductors 4 in the adhesive 30. The central conductors 4 may be appropriately set so as to be fixed to each other without particular limitation. Here, the fact that the adhesive 30 is adhered to the side surface of the plurality of central conductors 4 means that the adhesive 30 extends downward from the upper surface of each central conductor along the peripheral surface of each central conductor 4. , Corresponds to the lower end edge of the adhesive 30 located below the upper surface of each central conductor 4. The position of the lower end edge of the adhesive 30 existing on the side surface of the central conductor 4 in the vertical direction (direction perpendicular to the substrate 11) of FIG. 5 is 1 / of the average diameter of the central conductor 4 downward from the upper surface of the central conductor 4. It is preferable that the positions are separated by 4 or more. When the adhesive 30 is adhered to the central conductor 4 via the first preliminary soldering portion 51 as in the present embodiment, the reference of the position of the lower end edge is the upper surface of the first preliminary soldering portion 51. ..

In the present embodiment, the axial tip side of the adhesive 30 is arranged at a distance from the solder connection portion 50 (the connection portion between the central conductor 4 and the wiring 12) described later, but the shaft of the adhesive 30 is arranged. It is preferable that the tip edge on the tip side in the direction is arranged at a position closer to the solder connection portion 50. By arranging the adhesive 30 in this way, the plurality of center conductors 4 and the plurality of wirings 12 can be soldered near the portions of the plurality of center conductors 4 fixed by the adhesive 30. This makes it possible to further improve the individual (one-to-one correspondence) positioning accuracy of the plurality of center conductors 4 and the plurality of wirings 12. Further, as shown in the second embodiment described later, it is more preferable that the adhesive 30 is arranged so as to overlap the solder connection portion 50 (so as to cover the solder connection portion 50).

The adhesive 30 preferably has transparency. Since the adhesive 30 has transparency, the presence of a plurality of central conductors 4 can be confirmed through the adhesive 30, so that the electrical connection structure is more excellent in manufacturability.

The adhesive 30 withstands the heat applied when the plurality of first preliminary solder portions 51 and the plurality of second preliminary solder portions 52, which will be described later, are melted, and the plurality of first preliminary solder portions 51 and the plurality of second preliminary solder portions 52. It is preferable to have heat resistance so that the plurality of center conductors 4 can be positioned with respect to the plurality of wirings 12 until the 52 is cured and the plurality of center conductors 4 are fixed to the plurality of wirings 12.

Examples of the adhesive 30 include a thermosetting adhesive and a thermoplastic adhesive.

(Thermosetting adhesive)
As the thermosetting adhesive, for example, one containing an epoxy resin and a curing agent is used. By using an epoxy resin as the material of the adhesive 30, it is possible to improve the formability, heat resistance and adhesive strength of the adhesive 30.

Examples of the epoxy resin contained in the adhesive 30 include bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol S type epoxy resin, bisphenol AD type epoxy resin, and bisphenol A type and bisphenol F type copolymerized type. Examples thereof include epoxy resin, naphthalene type epoxy resin, novolak type epoxy resin, biphenyl type epoxy resin, dicyclopentadiene type epoxy resin and the like. The adhesive 30 may contain at least one of the above-mentioned epoxy resins.

The molecular weight of the epoxy resin can be appropriately selected in consideration of the performance required for the adhesive 30. For example, when a relatively high molecular weight epoxy resin is used, the formability tends to be high and the melt viscosity of the resin at the connection temperature tends to be high. On the other hand, when an epoxy resin having a relatively low molecular weight is used, the effect of increasing the crosslink density and improving the heat resistance tends to be obtained. Further, when an epoxy resin having a relatively low molecular weight is used, the effect of rapidly reacting with the above-mentioned curing agent at the time of heating to improve the adhesive performance can be obtained. Therefore, it is preferable to use a high molecular weight epoxy resin having a molecular weight of 15,000 or more and a low molecular weight epoxy resin having a molecular weight of 2000 or less in combination in terms of performance balance. The blending amount of these high molecular weight epoxy resin and low molecular weight epoxy resin can be appropriately selected. The above-mentioned "average molecular weight" refers to a polystyrene-equivalent molecular weight obtained by gel permission chromatography (GPC) developed in tetrahydrofuran (THF).

The adhesive 30 can obtain high adhesive strength by containing a curing agent for accelerating the curing of the epoxy resin. As the curing agent, for example, a latent curing agent is used. The latent curing agent is excellent in storage stability at low temperature and hardly causes a curing reaction at room temperature, but is a curing agent that rapidly performs a curing reaction by heat, light, or the like. Examples of such latent curing agents include imidazole-based, hydrazide-based, boron trifluoride-amine complexes, amineimides, polyamines, tertiary amines, alkylurea-based amines, dicyandiamides, acid anhydrides and the like. Phenolic compounds and variants thereof are exemplified, and one or a mixture of two or more of them can be used.

Further, among these latent curing agents, an imidazole-based latent curing agent is preferably used from the viewpoint of storage stability at low temperature and quick curing. As the imidazole-based latent curing agent, known ones can be used. More specifically, as the imidazole-based latent curing agent, an adduct of an imidazole compound with an epoxy resin is exemplified. Examples of the imidazole compound include imidazole, 2-methylimidazole, 2-ethylimidazole, 2-propylimidazole, 2-dodecylimidazole, 2-phenylimidazole, 2-phenyl-4-methylimidazole, 4-methylimidazole and the like.

These latent curing agents are preferably microencapsulated by being coated with a polymer substance containing polyurethane, polyester or the like as a main component, a metal such as nickel or copper, or an inorganic substance such as calcium silicate. By microencapsulating the latent curing agent in this way, it is possible to achieve both long-term storage stability and fast curing properties, which are contradictory characteristics. Therefore, as the latent curing agent, a microcapsule type imidazole-based latent curing agent is particularly preferable.

(Thermoplastic adhesive)
The thermoplastic adhesive contains a thermoplastic resin as a main component. Examples of the thermoplastic resin include polyvinyl acetal such as polyvinyl butyral, phenoxy resin, acrylic resin, methacrylic resin, polyamide, polyacetal, polyphenylene sulfide, polyimide, polytetrafluoroethylene, polyether ether ketone, polyether sulfone, urethane, polyester, and the like. Examples thereof include polyethylene, polypropylene, and polystyrene. Among these, phenoxy resin, polyamide, polyimide and the like are preferably used as the thermoplastic resin.

<Base film>
In the present embodiment, the base film 40 made of synthetic resin is arranged on the surface of the adhesive 30 (the surface opposite to the plurality of central conductors 4). By further including the base film 40 in the electrical connection structure, the adhesive 30 is reinforced, so that the plurality of exposed center conductors 4 are more reliably fixed. Therefore, it becomes easier to manufacture the electrical connection structure. The base film 40 is adhered to the surface of the adhesive 30, and is adhered to a plurality of central conductors 4 via the adhesive 30. The base film 40 is formed to have the same size as the adhesive 30 in a plan view, for example.

Examples of the base film 40 include a film containing a super engineering plastic as a main component, which is inexpensive and easily available. Examples of such super-engineering plastics include polyimides, polyamideimides, polyetherimides, polyetheretherketones, polyphenylene sulfides, polyallylates, liquid crystal polymers, polysulphons, polyethersulfons, fluororesins other than polytetrafluoroethylene, and the like. Can be mentioned.

Further, the base film 40 withstands the heat applied at the time of melting of the plurality of first preliminary solder portions 51 and the plurality of second preliminary solder portions 52, which will be described later, and the plurality of first preliminary solder portions 51 and the plurality of second preliminary solder portions 51. It is preferable to have heat resistance so that the plurality of center conductors 4 can be positioned with respect to the plurality of wirings 12 until the preliminary solder portion 52 is cured and the plurality of center conductors 4 are fixed to the plurality of wirings 12. Further, the base film 40 preferably has high adhesiveness to the adhesive 30.

The base film 40 preferably has transparency. Since the base film 40 has transparency, it becomes possible to visually recognize the inside (wiring 12 side) of the base film 40. That is, it becomes possible to visually recognize the fixed state (relative position between the plurality of center conductors 4 and the plurality of wirings 12) of the plurality of center conductors 4 exposed by the adhesive 30 via the base film 40. Therefore, it becomes easier to manufacture the electrical connection structure.

Polyimide is an example of a super engineering plastic that meets these requirements. Therefore, it is preferable that the base film 40 contains polyimide as a main component. The "main component" refers to a component having the largest content ratio in terms of mass, for example, a component having a content of 50% by mass or more.

As the lower limit of the average thickness of the base film 40, 5 μm is preferable, and 10 μm is more preferable. The upper limit of the average thickness of the base film 40 is preferably 100 μm, more preferably 50 μm. If the average thickness of the base film 40 is less than the above lower limit, its strength may be insufficient. On the other hand, if the average thickness of the base film 40 exceeds the above upper limit, the electrical connection structure may become unnecessarily thick.

<Solder connection>
Each of the plurality of solder connecting portions 50 is formed by solder connecting the plurality of center conductors 4 and the plurality of wirings 12. In the present embodiment, a plurality of central conductors 4 covered with a plurality of first preliminary solder portions 51 and a plurality of wirings 12 covered with a plurality of second preliminary solder portions 51 are superposed, and these superposed portions are superposed. Is heated, the plurality of first preliminary solder portions 51 and the plurality of second preliminary solder portions 52 are melted, and the plurality of solder connection portions 50 are formed by the superposed portions thereof.

The solder constituting the first preliminary solder portion 51 and the second preliminary solder portion 52 is not particularly limited, and for example, lead-free solders such as SnAgCu alloy, SnZnBi alloy, SnCu alloy, and SnAgInBi alloy can be used.

[Electrical connection method]
Next, FIGS. 8 to 17 describe an electrical connection structure between the insulated wire 1 and the printed wiring board 10 in the present embodiment shown in FIGS. 1 to 7, that is, a method for manufacturing a connecting body of the insulated wire 1 and the printed wiring board 10. Will be explained with reference to.

The electrical connection method includes an outer cover removing step of removing the axial tip portions of the outer cover 7 of the plurality of insulated wires 1, and the axial tip portions of the plurality of external conductors 6 exposed after the outer cover removal work. After the external conductor removing step, the fixing step of fixing the exposed external conductors 6 after the external conductor removing step, and the axial tip portions of the exposed insulating layer 5 after the fixing step. The insulating layer removing step for removing, the first preliminary soldering step for pre-soldering each of the exposed central conductors 4 after the insulating layer removing step, and the second pre-soldering step for pre-soldering each of the plurality of wirings 12. A positioning step of arranging and positioning the exposed plurality of central conductors 4 in a stripe shape so as to overlap the plurality of wirings 12, and bonding to the upper surface and side surfaces of the exposed plurality of center conductors 4 after the positioning step. A first bonding step of adhering the agent 30 in a strip shape along a direction perpendicular to the axial direction of the plurality of central conductors 4, and a laminating step of laminating a base film on the upper surface of the adhesive 30 after the first bonding step. After the laminating step, a contact step of bringing the exposed plurality of central conductors 4 into contact with the plurality of wirings 12 in a one-to-one correspondence manner, and after the contacting step, between the plurality of center conductors 4 and the plurality of wirings 12. It includes a second bonding step of bonding with solder.

<Coat removal process>
In this step, the axial tip portion thereof is removed from the outer cover 7 of the plurality of insulated wires 1 as shown in FIG. As a result, as shown in FIG. 9, a plurality of outer conductors 6 are exposed. As a method for removing the plurality of coats 7, for example, a method of cutting the plurality of coats 7 by laser irradiation and peeling off the plurality of coats 7 on the tip side from the plurality of outer conductors 6 to remove the plurality of coats 7 can be used. can. FIG. 9 shows a state in which the axial tip portions of the plurality of outer covers 7 are pulled out halfway. The axial tip portions of the plurality of outer covers 7 are completely removed together with the axial tip portions of the plurality of outer conductors 6 in the external conductor removing step described later. The plurality of jackets 7 may be completely removed before the outer conductor removing step.

<External conductor removal process>
In this step, after the outer cover removing step, as shown in FIG. 10, the axial tip portions of the exposed plurality of outer conductors 6 are removed. In this step, the axial tip portion of the exposed outer conductor 6 is removed together with the axial tip portion of the outer cover 7 described above. As a result, the axial tip portions of the plurality of insulating layers 5 are exposed. As a method for removing these outer conductors 6, for example, a method of cutting a plurality of outer conductors 6 by laser irradiation and peeling off the axial tip portions of the plurality of outer conductors 6 from each insulating layer 5 to remove them can be used. can. FIG. 10 illustrates an embodiment in which the axial tips of the plurality of outer conductors 7 and the axial tips of the plurality of outer conductors 6 are collectively pulled and removed together with the axial tips of the outer cover 7.

<Fixing process>
In this step, after the outer conductor removing step, as shown in FIG. 11, the axial tip portions of the exposed plurality of outer conductors 6 are fixed by the fixing portions 20. The fixing portion 20 is as described above.

<Insulation layer removal process>
In this step, after the outer conductor removing step, as shown in FIG. 12, the axial tips of the plurality of exposed insulating layers 5 are removed. As a result, the axial tip portions of the plurality of central conductors 4 are exposed. As a method for removing the plurality of insulating layers 5, for example, a method of cutting the plurality of insulating layers 5 by laser irradiation and peeling the plurality of insulating layers 5 from the plurality of central conductors 4 to remove them can be used. FIG. 12 illustrates an embodiment in which the axial tip portions of the plurality of insulating layers 5 are pulled and removed. By further pulling the axial tips of the plurality of insulating layers 5 from the state shown in FIG. 12, these axial tips are completely removed.

<First preliminary soldering process>
In this step, after the insulating layer removing step, as shown in FIG. 13, preliminary soldering is performed on each of the exposed central conductors 4. Specifically, in this step, each of the exposed central conductors 4 is wetted with solder in a molten state by heating, so that each central conductor 4 holds the first preliminary solder portion 51.

<Second preliminary soldering process>
In this step, although not shown, preliminary soldering is performed on each of the plurality of wirings 12 of the printed wiring board 10. Specifically, in this step, the plurality of wirings 12 of the printed wiring board 10 are each wetted with solder in a molten state by heating, so that the plurality of wirings 12 hold the second preliminary soldering portion 52 (FIGS. 2 and 2). 17). The timing of performing this step may be prior to the positioning step, and is not particularly limited.

<Positioning process>
In this step, the plurality of exposed center conductors 4 are arranged and positioned in a stripe shape so as to overlap the plurality of wirings 12. Specifically, in this step, for example, a positioning jig 61 and a pedestal 60 as shown in FIG. 14 are used, and a plurality of central conductors 4 are arranged in a stripe shape having the same pitch as the plurality of wirings 12 of the printed wiring board 10. Position.

The positioning jig 61 has a plurality of V-shaped positioning grooves 62 into which each center conductor 4 is fitted. The pedestal 60 supports the plurality of insulating layers 5 when the plurality of center conductors 4 are fitted into the plurality of positioning grooves 62.

<First bonding process>
In this step, after the positioning step, as shown in FIG. 15, the adhesive 30 is applied to the upper surface and the side surface of the plurality of exposed center conductors 4 (covered by the first preliminary solder portion 51) in the axial direction. Adhere in a strip shape along the direction perpendicular to (the left-right direction in FIG. 15). Specifically, in this step, the adhesive is spread over the upper surface of the plurality of central conductors 4 positioned in the positioning step (via the first preliminary soldering portions 51) and is located on the side surface. 30 is glued. As a result, the adhesive 30 is adhered to the upper surface and the side surface of the plurality of central conductors 4. The adhesive 30 makes it possible to hold the plurality of central conductors 4 together so as to maintain the striped arrangement. That is, by lifting the plurality of insulated wires 1 (see FIG. 1) from the state shown in FIG. 15, as shown in FIG. 16, the plurality of central conductors 4 can be lifted at the same time.

When the adhesive 30 is composed of a thermosetting adhesive, it is preferable to keep the adhesive 30 in the B stage state in this first bonding step. By keeping the adhesive 30 in the B stage state in this way, the adhesive 30 is easy to handle and can exhibit good adhesiveness.

<Laminating process>
In this step, after the first bonding step, the base film 40 is laminated on the upper surface of the adhesive 30 as shown in FIGS. 15 and 16 described above. Specifically, in this step, the base film 40 is adhered to the upper surface of the adhesive 30 before it is cured. As a result, the base film 40 is laminated on the adhesive 30. The base film 40 is adhered to the adhesive 30 by the adhesive force of the adhesive 30. By laminating the base film 40 on the adhesive 30 in this way, the strength of the adhesive 30 is reinforced.

<Contact process>
In this step, after the laminating step, as shown in FIG. 17, the exposed plurality of central conductors 4 are arranged in a one-to-one correspondence relationship (via each first preliminary soldering portion 51 and each second preliminary soldering portion 52). Contact a plurality of wires 12. Specifically, in this step, a plurality of central conductors 4 are placed on the surface of the plurality of wirings 12 of the printed wiring board 10 in a state where the striped arrangement is maintained by the adhesive 30 and the base film 40. The solder portion 51 and the second preliminary solder portion 52 are brought into contact with each other via the solder portion 51 and the second preliminary solder portion 52, respectively. At the same time, the fixing portion 20 is brought into contact with the ground wire 14 of the printed wiring board 10. At this time, the relative positions of the adhesive 30 and the base film 40 are visually confirmed so that the tips of the plurality of central conductors 4 projecting from the adhesive 30 and the base film 40 to the tip side overlap with the plurality of wirings 12. Fine-tune. When the adhesive 30 and the base film 40 have transparency, it is possible to confirm the alignment of the plurality of center conductors 4 and the plurality of wirings 12 through them.

After arranging the plurality of center conductors 4 so as to overlap the plurality of wirings 12, both ends of the adhesive 30 extending from both outer sides of the plurality of center conductors 4 are printed wiring boards 10 together with both ends of the base film 40. Adheres to the surface of the substrate 11 in. Thereby, the plurality of central conductors 4 can be fixed in a state where they are in contact with the surfaces of the plurality of wirings 12.

<Second bonding process>
In this step, after the contacting step, the plurality of center conductors 4 and the plurality of wirings 12 are bonded with solder. Specifically, in this step, the plurality of center conductors 4 and the plurality of wirings 12 held in contact with each other via the first preliminary solder portion 51 and the second preliminary solder portion 52 are heated to heat the first preliminary solder portion. By melting the solder portion 51 and the second preliminary solder portion 52, the plurality of central conductors 4 and the plurality of wirings 12 are mechanically and electrically connected. As a result, as shown in FIGS. 1 and 2, a plurality of solder connection portions 50 of the plurality of center wirings 4 and the plurality of wirings 12 are formed. In this way, by melting the first preliminary soldering portion 51 for the plurality of central conductors 4 and the second preliminary soldering portion 52 for the plurality of wirings 12, the plurality of central conductors 4 do not supply new solder. And a plurality of wires 12 can be connected.

The heating for melting the first preliminary solder portion 51 and the second preliminary solder portion 52 heats a plurality of insulated wires 1 and a printed wiring board 10 whose connection state is maintained by, for example, an adhesive 30 and a base film 40. It can be placed in a furnace. Further, in order to melt the first preliminary solder portion 51 and the second preliminary solder portion 52, the heating body may be pressed against at least one of the front surface of the base film 40 and the back surface of the printed wiring board 10.

[Second Embodiment]
[Electrical connection structure and connection body]
In the electrical connection structure and connection body of the first embodiment described above, the adhesive does not overlap (extend to the connection portion) with the connection portion of the plurality of exposed center conductors and the plurality of adhered portions (wiring in this case). In contrast to the (not) aspect, in the electrical connection structure and connection body of the present embodiment, the adhesive overlaps (so that it overlaps with the connection portion) the connection portion of the plurality of exposed center conductors 4 and the plurality of wirings 12. It is arranged so that it extends to). Further, the base film arranged on the surface of the adhesive is also arranged so as to overlap the connection portion. Further, by arranging the adhesive in this way, the tip side in the axial direction of the solder connecting portion 50 with respect to the central conductor 4 is raised above the upper surface of the central conductor 4.

As described above, the electrical connection structure of the present embodiment has exactly the same configuration as the electrical connection structure of the first embodiment except that the adhesive and the base film are arranged so as to overlap the connection portion. Have. Therefore, the present embodiment will be described only with a configuration different from that of the first embodiment (that is, the adhesive and the base film are arranged so as to overlap the connection portion). Further, the same members as those in the first embodiment are designated by the same reference numerals, and the description thereof will be omitted.

<Adhesive>
As described above, and as shown in FIGS. 18, 19 and 20, in the electrical connection structure and connection body of the present embodiment, the adhesive 30 is a plurality of exposed center conductors 4 and a plurality of wirings 12. It overlaps with the connection part. Specifically, in addition to the adhesive 30 straddling the exposed central conductor 4 and the insulating layer 5 in the same manner as in the first embodiment described above, the adhesive 30 further spans the exposed central conductor 4 and the plurality of insulating layers 5. It overlaps with the connection portion of the wiring 12. That is, the axial rear end side (insulation layer 5 side) of the adhesive 30 straddles the plurality of central conductors 4 and the insulating layer 5, and the axial tip side (wiring 12 side) is the plurality of central conductors 4 and the plurality. It overlaps with the connection portion of the wiring 12.

By arranging the adhesive 30 in this way, the portions of the plurality of central conductors 4 connected to the plurality of wirings 12 are fixed by the adhesive 30, so that the plurality of center conductors 4 and the plurality of wirings 12 are overlapped. When aligning, the alignment accuracy can be further improved. In addition, since the plurality of center conductors 4 and the plurality of wirings 12 can be soldered near the portions of the plurality of center conductors 4 fixed by the adhesive 30, misalignment during soldering is reduced. be able to.

As described above in the first embodiment, in the present embodiment, as shown in FIG. 18, the axial tip side of the adhesive 30 overlaps with the solder connection portion 50 (the connection portion between the central conductor 4 and the wiring 12). (To cover the solder connection portion 50). That is, the adhesive 30 is arranged so as to extend toward the tip end side in the axial direction until it overlaps with the solder connection portion 50. In this case, the axial tip side of the adhesive 30 may overlap a part of the solder connection portion 50 or may overlap the entire solder connection portion 50. By arranging the axial tip side of the adhesive 30 in this way, the plurality of center conductors 4 and the plurality of wirings 12 are soldered in the immediate vicinity and directly below the portions of the plurality of center conductors 4 fixed by the adhesive 30. can do. This makes it possible to further improve the individual (one-to-one correspondence) positioning accuracy of the plurality of center conductors 4 and the plurality of wirings 12.

The lower limit of the average length in the axial direction (vertical direction in FIG. 18) of the portion of the adhesive 30 that overlaps with the connection portion (that is, the portion that overlaps with the wiring 12) is preferably 10 μm. The upper limit of the average length in the axial direction of the portion of the adhesive 30 that overlaps with the connection portion is preferably 1500 μm. When the average length in the axial direction of the portion of the adhesive 30 that overlaps with the connection portion is equal to or greater than the lower limit, the alignment accuracy of the plurality of center conductors 4 and the plurality of wirings 12 is further improved. On the other hand, when the average length in the axial direction is equal to or less than the upper limit, it is possible to prevent the electrical connection structure from becoming unnecessarily large.

For example, in the cross section shown in FIG. 19, the average thickness above the upper surface (the surface in contact with the upper end edge) of the plurality of center conductors 4 in the adhesive 30, including the portion overlapping the connection portion, is the above-mentioned first embodiment. It can be set in the same way as the form. That is, as the lower limit of the average thickness from the upper surface to the upper side of the plurality of center conductors 4 in the adhesive 30, 1/10 of the average diameter of the plurality of center conductors 4 is preferable, and 1/5 is more preferable. The upper limit of the average thickness of the plurality of center conductors 4 from the upper surface to the upper side in the adhesive 30 is preferably 2/3, more preferably 1/2 of the average diameter of the plurality of center conductors 4. If the average thickness is less than the lower limit, it may be difficult for the adhesive 30 to sufficiently protect the connection portions of the plurality of center conductors 4 and the wiring 12. If the average thickness exceeds the upper limit, the electrical connection structure may become unnecessarily thick. As in the first embodiment described above, when the adhesive 30 is bonded to the central conductor 4 via the first preliminary solder portion 51 as in the present embodiment, the average thickness of the upper side is the first. It is the average thickness from the upper surface to the upper side of the preliminary solder portion 51. As in the first embodiment described above, the present embodiment shows the mode in which the adhesive 30 is also arranged on the upper surface, but in addition to this, as described above, the adhesive 30 is arranged on the side surface, while the adhesive 30 is arranged on the side surface. It is also possible to adopt an embodiment that is not arranged on the upper surface. In this case, the average thickness of the plurality of central conductors 4 in the adhesive 30 from the upper surface to the upper side is 0.

For example, in the cross section shown in FIG. 19, the size of the region where the adhesive 30 adheres to the side surface of the plurality of center conductors 4, including the portion overlapping the connection portion, that is, the plurality of center conductors in the adhesive 30. The degree of extension from the upper surface of 4 to the lower side can be set in the same manner as in the first embodiment described above. That is, the extent to which the adhesive 30 extends downward from the upper surface of the plurality of central conductors 4 is not particularly limited, and the plurality of central conductors 4 can be appropriately set so as to be fixed to each other. Here, as in the first embodiment described above, the fact that the adhesive 30 is adhered to the side surfaces of the plurality of center conductors means that the adhesive 30 is attached to the upper surface of each center conductor along the peripheral surface of each center conductor 4. It corresponds to extending downward from, that is, the lower end edge of the adhesive 30 is located below the upper surface of each central conductor 4. Similar to the first embodiment described above, the position of the lower end edge of the adhesive 30 existing on the side surface of the central conductor 4 in the vertical direction (direction perpendicular to the substrate 11) of FIG. 19 is downward from the upper surface of the central conductor 4. It is preferable that the position is separated by 1/4 or more of the average diameter of the center conductor 4. As in the first embodiment described above, when the adhesive 30 is bonded to the center conductor 4 via the first preliminary solder portion 51 as in the present embodiment, the reference for the position of the lower end edge is the above-mentioned first embodiment. 1 This is the upper surface of the preliminary solder portion 51. Further, in the present embodiment, the adhesive 30 may cover not only the central conductor 4 but also the peripheral surface of the wiring 12. In this case, the adhesive 30 may cover the side surface of the wiring 12, or may cover a part of the side surface of the wiring 12 and the upper surface of the wiring 12.

<Base film>
In the present embodiment, the base film 40 is formed to have the same size as the adhesive 30 in a plan view, as in the first embodiment described above. Therefore, in the present embodiment, similarly to the adhesive 30, the plurality of centers in which the axial rear end side of the base film 40 is exposed straddles the plurality of central conductors 4 and the plurality of insulating layers 5, and the axial front end side is exposed. It overlaps with the connection portion of the conductor 4 and the plurality of wirings 12.

[Electrical connection method]
Next, an electrical connection structure between the insulated wire 1 and the printed wiring board 10 in the present embodiment, that is, a method of manufacturing a connecting body of the insulated wire 1 and the printed wiring board 10 will be described.

The electrical connection method is the same as that of the first embodiment described above, that is, the outer cover removing step, the outer conductor removing step, the fixing step, the insulating layer removing step, the first preliminary soldering step, and the second preliminary soldering. It includes a step, a positioning step, a first bonding step, a laminating step, a contacting step, and a second bonding step. In the electrical connection method of the present embodiment, in the first bonding step, the axial coating region in the connecting portion 30 is changed, the axial dimension of the base film 40 in a plan view is changed, and the laminating step is performed. It is different because it has exactly the same configuration as the electrical connection method of the first embodiment described above, except that the base film 40 is laminated on the adhesive 30 applied to the region changed as described above. Only the configuration will be described.

<First bonding process>
In this step, as shown in FIGS. 18 to 20 described above, the adhesive 30 is applied to the same region as that of the second embodiment described above in the axial direction. Specifically, in addition to the axial rear end side of the adhesive 30 straddling the plurality of central conductors 4 and the plurality of insulating layers 5, the axial tip side of the adhesive 30 is further the plurality of central conductors 4 and the plurality. The adhesive 30 is applied so as to overlap with the connection portion of the wiring 12. In this case, as described above, it is preferable to apply the adhesive 30 so that the axial tip side of the adhesive 30 overlaps with each solder connection portion 50 (of the plurality of center conductors 4 and the plurality of wirings 12). Other configurations in the first bonding step are exactly the same as in the first embodiment.

<Laminating process>
In this step, as shown in FIGS. 18 to 20, the base film 40 is laminated on the adhesive 30 applied in the first bonding step. That is, in addition to the axial rear end side of the base film 40 straddling the plurality of central conductors 4 and the plurality of insulating layers 5 via the adhesive 30, the axial front end side of the base film 40 is further plurality. The base film 40 is laminated on the adhesive 30 so as to overlap the connection portions of the center conductor 4 and the plurality of wirings 12 via the adhesive 30. Other configurations in the laminating process are exactly the same as in the first embodiment.

[advantage]
In the electrical connection structure, the exposed center conductors 4 of the plurality of insulated wires 1 can be held by the adhesive 10 at intervals corresponding to the plurality of wirings 12 of the printed wiring board 10, so that the plurality of exposed centers can be held. The conductor 4 can be reliably arranged on the plurality of wirings 12 at the same time. Furthermore, since a flexible insulating sheet having an arrangement groove as described in Patent Document 1 is not used, it is easy to manufacture and it is possible to suppress an increase in the thickness of the connecting body. In addition, the presence of the adhesive 30 on the side surfaces of the plurality of exposed center conductors 4 makes the center conductors 4 more reliably fixed. Therefore, in the electrical connection structure, the central conductors 4 of the plurality of insulated wires 1 are easily and surely connected to the plurality of wirings 12 in a one-to-one correspondence without increasing the thickness of the connecting body.

Further, since the connecting body of the insulated wire 1 and the printed wiring board 10 has the electrical connection structure, the central conductors 4 of the plurality of insulated wires 1 can be formed without increasing the thickness of the connecting body as described above. It is easily and surely connected to a plurality of wires 12 in a one-to-one correspondence relationship.

[Other embodiments]
It should be considered that the embodiments disclosed this time are exemplary in all respects and not restrictive. The scope of the present invention is not limited to the configuration of the above embodiment, but is indicated by the scope of claims, and is intended to include all modifications within the meaning and scope equivalent to the scope of claims. To.

For example, the electrical connection structure does not use the first preliminary soldering portion 51 and the second preliminary soldering portion 52, and in the first bonding step, soldering the plurality of center conductors 4 and the plurality of wirings 12 while heating them. May be supplied. Further, pre-soldering may be performed only on one of the plurality of center conductors 4 and the plurality of wirings 12.

For example, the positioning step may be performed by a method other than using a jig as shown in the above embodiment. For example, in a state where the adhesive 30 is adhered on the base film 40 and the adhesive 30 is placed on a horizontal table with the adhesive 30 facing upward, the central conductors 4 of the plurality of insulated wires 1 are placed on the adhesive 30. It may be arranged while positioning one by one. That is, the positioning step and the first bonding step (further, the laminating step) may be performed at the same time.

For example, in the above embodiment, the adhesive 30 and the base film 40 are arranged so as to straddle the exposed plurality of central electric wires 4 and the plurality of insulating layers 5. For example, as shown in FIG. 21, the adhesive 30 is arranged. And the base film 40 may be arranged so as not to cover the plurality of insulating layers 5 but to cover only the plurality of exposed center conductors 4. In this case, as shown in FIG. 21, the adhesive 30 and the base film 5 are spaced from the plurality of insulating layers 5 so that their trailing end edges do not come into contact with the tip edges of the plurality of insulating layers 5. You can place it in a space.

For example, in the electrical connection structure, both ends of the adhesive 30 and the base film 40 in the direction perpendicular to the axial direction do not necessarily have to be adhered to the printed wiring board 10. That is, it is not necessary to extend both ends of the adhesive 30 and the base film 40 in the direction perpendicular to the axial direction to the outside of the central conductor 4 located on both outer sides. Further, only one of the two ends may be adhered to the pret wiring board 10.

For example, in the above embodiment, the base film 40 is laminated on the adhesive 30, but the base film 40 may be peeled off. Further, for example, in the electrical connection structure, an embodiment in which only the adhesive 30 is used and the base film 40 is not used may be adopted.

For example, in the above embodiment, the adhesive 30 is adhered to the upper surface and the side surface of the plurality of central conductors 4, but the adhesive 30 may be adhered only to the side surface of the plurality of central conductors 4.

For example, in the above embodiment, the central conductor 4 and the wiring 12 are in contact with each other via solder (first preliminary solder portion 51 and second preliminary solder portion 52), but the central conductor 4 and the broken line 12 are in direct contact with each other. May be done.

For example, the component provided with the connected portion in the electrical connection structure may be an electronic component other than the printed wiring board, for example, an electronic component such as a connector.

For example, in the above embodiment, the embodiment in which the insulated wire has the central conductor, the insulating layer, the outer conductor and the outer cover has been described, but the insulated wire has the central conductor and the insulating layer and has the outer conductor and the outer cover. It is also possible to adopt a mode that does not.

For example, as shown in the above embodiment, after connecting the plurality of central conductors 4 and the plurality of connected portions, these connecting portions may be further covered with an insulating resin such as UV resin. By further covering the connecting portion with the insulating resin in this way, the connecting portion can be more reliably protected.

The present invention can be applied to the connection of an insulated electric wire, and can be suitably used for a connecting body of an insulated electric wire and a printed wiring board.

1 Insulated wire 4 Center conductor 5 Insulated layer 6 External conductor 7 Outer cover 10 Printed wiring board 11 Board 12 Wiring (connected part)
14 Ground wire 20 Fixed part 30 Adhesive 40 Base film 50 Solder connection part 51 First spare solder part 52 Second spare solder part 60 Pedestal 61 Positioning jig 62 Positioning groove

Claims (9)

An electrical connection structure in which a plurality of center conductors in a plurality of insulated wires having an insulating layer covering the center conductor and the peripheral surface of the center conductor and a plurality of connected portions are connected.
The plurality of central conductors are exposed in the axial tip region of the plurality of insulated wires, and are superimposed on the plurality of connected portions in a one-to-one correspondence relationship.
The solder connection portion that adheres between the plurality of exposed center conductors and the plurality of connected portions, and the solder connection portion.
The exposed center conductors are provided with an adhesive that adheres to each other for positioning.
An electrical connection structure in which the adhesive is adhered to the sides of the plurality of exposed central conductors and is arranged along a direction perpendicular to the axial direction. The electrical connection structure according to claim 1, wherein the adhesive is further adhered to the upper surface of the plurality of exposed central conductors. The electrical connection structure according to claim 1 or 2, wherein the adhesive has transparency. The electrical connection structure according to claim 1, claim 2 or claim 3, wherein the adhesive is arranged on the insulating layer side with respect to the axial tip edge of the exposed plurality of central conductors. The electrical connection structure according to any one of claims 1 to 4, wherein the adhesive is arranged across the exposed central conductor and the plurality of insulating layers. The electrical connection structure according to any one of claims 1 to 5, wherein the adhesive is arranged so as to overlap the connection portions of the exposed central conductor and the plurality of connected portions. The invention according to any one of claims 1 to 6, further comprising a synthetic resin base film that is adhered to the exposed central conductors via the adhesive and is arranged perpendicular to the axial direction. The electrical connection structure described. The electrical connection structure according to claim 7, wherein the base film has transparency. The electrical connection structure according to any one of claims 1 to 8 is provided.
A connection body of an insulated wire and a printed wiring board in which the plurality of connected portions are the plurality of wirings in a printed wiring board having a board and a plurality of wirings laminated on the surface of the board.

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