JPH10215047A - Printed board - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a printed board wherein interconnections between circuit wirings formed on both surfaces of the printed board can be securely maintained regardless of the temperature change, etc. SOLUTION: A printed board is provided with an insulating substrate 4 with a through hole 6, a circuit wiring 1A formed on one surface of the substrate 4, a circuit wiring 1B formed on the other surface of the substrate 4, and a lead 3 for connecting a connecting portion 1a connected to the circuit wiring 1A to a connecting portion 1b connected to the circuit wiring 1B. The connecting portion 1a is provided with a plurality of tongues 2 covering at least a portion of the other open end of the through hole 6. The lead 3 is inserted into the through hole 6, and is held by the ends of a plurality of tongues 2 formed at the connecting portion 1a and the ends of a plurality of tongues 2 formed at the connecting portion 1b.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a printed circuit board, and more particularly to a printed circuit board to which circuit wirings formed on both sides of a substrate are connected via leads.

[0002]

2. Description of the Related Art In a printed circuit board, circuit wiring made of a conductive film is formed on both sides of the board. The circuit wirings formed on both sides of the substrate are connected to each other via a conductive wire (hereinafter referred to as a lead) penetrating the substrate at a portion that needs to be electrically connected to each other (hereinafter referred to as a connection portion). I have.

A lead of a conventional printed circuit board is inserted into a through hole formed in the board, and is soldered to connection portions of circuit wiring on both sides. For this reason, in a conventional printed circuit board, in an atmosphere having a large temperature change, cracks or peeling may occur at the connection portion due to a difference in thermal expansion between the board and the lead.

In order to avoid damage to the connecting portion due to thermal expansion between the substrate and the lead, Japanese Patent Laid-Open No. 63-42198 discloses a method for receiving the displacement of the lead by elastically deforming the connecting portion of the circuit wiring. It has been disclosed.

According to the method disclosed in JP-A-63-42198, as shown in FIGS. 7 and 8, connection of circuit wiring covering both open ends of a through hole 8 having a diameter larger than that of a lead 7 is shown. The leads 7 are soldered to the portions 11a and 11b, and circuit wirings on both surfaces of the substrate 12 are connected. The displacement of the lead 7 due to the difference in thermal expansion between the substrate 12 and the lead 7 is caused by the connection 11 of the circuit wiring.
a and 11b are received by elastic deformation.

[0006]

However, Japanese Patent Application Laid-Open No.
According to the method disclosed in Japanese Patent No. 42198, the connection portion of the circuit wiring can be displaced only in a direction perpendicular to the substrate of the lead, and cannot be displaced in a direction other than the direction perpendicular to the substrate. For this reason, when displacement other than the direction perpendicular to the substrate occurs, the connection portion may be cracked or peeled off, and the connection portion may be damaged.

Further, since the lead and the connection portion of the circuit wiring are connected by solder, a portion of the connection portion to which the solder is attached cannot be deformed. For this reason, in order for the connecting portion to elastically deform to sufficiently receive the displacement of the lead, the connecting portion must be large. Therefore, a large space for mounting the connection unit is required on the substrate.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and has as its object to provide a printed circuit board that can reliably maintain connections between circuit wirings formed on both surfaces of the printed circuit board regardless of temperature changes. I do. Another object of the present invention is to provide a printed circuit board that requires a small space for a connection portion of a circuit wiring.

[0009]

In order to achieve the above object, a printed circuit board according to the present invention comprises an insulating substrate having a through hole and a first circuit wiring provided on one surface of the substrate. A second circuit wiring disposed on the other surface of the substrate, and a second circuit wiring connected to the first circuit wiring and formed to cover at least a part of one opening end of the through hole; A plurality of first tongue-shaped protrusions for holding a wire for connecting the first circuit wiring and the second circuit wiring inserted into the hole; Formed over at least a portion of the other open end of the hole;
A plurality of second holding members for holding the wire inserted into the through hole
And a tongue-shaped projection.

According to this structure, the plurality of tongue-shaped projections hold the wire for connecting the first circuit wiring and the second circuit wiring, and the plurality of tongue-shaped projections receive the displacement of the wire. . Therefore, the connection between the first circuit wiring and the second circuit wiring is
A printed board that can be reliably maintained regardless of a temperature change or the like can be obtained.

Further, since the first circuit wiring and the second circuit wiring are connected to the wire without using solder, the entire plurality of tongue-shaped projections are elastically deformed. For this reason, a printed circuit board requiring a small space at a connection portion between the first circuit wiring and the second circuit wiring can be obtained.

Further, the first member is inserted into the through hole, and
And a wire that is held by the tongue-shaped projections and the second tongue-shaped projections and that connects the first circuit wiring and the second circuit wiring.

Further, the first tongue and the second tongue are provided.
It is preferable that the tongue-like projections are formed of an inverted fan-shaped conductor film, and the tip of the first tongue-like projection and the tip of the second tongue-like projection hold the wire.

The first tongue-shaped projection and the second tongue-shaped projection are curved to the outside or the inside of the through hole, and a side surface portion of the first tongue-shaped projection and the second tongue-shaped projection are formed. The side portion of the projection may hold the wire.

According to this configuration, the wire is in contact with the side portions of the tongue-shaped projections 1 and 2. Therefore, even when the displacement of the wire is large, the tongue 1 and the tongue 2
Can obtain a printed circuit board that can receive the displacement of the wire and reliably maintain the connection between the first circuit wiring and the second circuit wiring regardless of a temperature change or the like.

Further, the first tongue-like projection is formed by folding back, and a first projection covering at least a part of one opening end of the through-hole and the second tongue-like projection are folded back. A second protrusion that covers at least a part of the other open end of the through-hole, and wherein the tip of the first protrusion and the tip of the second protrusion are connected to the wire. You may keep it.

According to this configuration, the first protrusion and the second protrusion are provided.
Function as a guide when the wire is inserted into the through hole, and the wire is smoothly mounted on the substrate. Therefore, the assembling work is facilitated, and the assembling work time can be reduced.

[0018]

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

As shown in FIGS. 1 and 2, the printed circuit board according to the present embodiment includes a substrate 4 made of an insulator such as a glass epoxy resin and circuit wirings 1A and 1B provided on both surfaces of the substrate 4. And a lead 3 for electrically connecting the circuit wirings 1A and 1B.

The substrate 4 has a cylindrical through-hole 6 at a position (connection point) where the circuit wirings 1A and 1B are to be connected. The diameter of the through hole 6 is formed larger than the diameter of the lead 3.

The circuit wirings 1A and 1B are made of a conductor film of a heat-treated thin metal plate (for example, a copper alloy foil having excellent elasticity such as phosphor bronze or beryllium copper).

At a connection point of the circuit wiring 1A, a connection portion 1a which covers a part of one opening end of the through hole 6 is formed.
At a connection point of the circuit wiring 1B, a connection portion 1b that covers a part of the other opening end of the through hole 6 is formed.

Each of the connection portions 1a and 1b of the circuit wiring is formed with several tongue-shaped projections 2 each having an inverted fan shape with the guide hole 5. The diameter of the guide hole 5 is smaller than the diameter of the lead 3.

As shown in FIG. 2, the leads 3 are supported at their distal ends by the elastic force of the tongue-shaped projections 2 by penetrating the guide holes 5 of the connecting portions 1a and 1b. Since the lead 3 is supported by the elastic force of the tongue 2,
It is possible to move against the elastic force of the tongue 2.

Accordingly, when the lead 3 is displaced in the direction 3a perpendicular to the substrate 4 due to, for example, a difference in thermal expansion between the lead 3 and the substrate 4 or an external impact, etc., FIG. As shown in (1), the tongue-shaped projection 2 is deformed by its elasticity to receive the displacement of the lead 3 in the direction 3a. Further, even after the lead 3 slides in the direction 3a, the tongue-shaped projection 2 maintains contact with the lead 3 due to its elastic force. Thereby, the electrical connection between the circuit wirings 1A and 1B is maintained.

Further, when the lead 3 is displaced in the direction 3b parallel to the substrate 4, as shown in FIG. 3B, the tongue-shaped projection 2 is elastically deformed, so that the displacement of the lead 3 is received. I do. At this time, the contact between the lead 3 and the tongue 2 is maintained, so that the electrical connection between the circuit wirings 1A and 1B is maintained.

Next, a method of forming the connection portions 1a and 1b will be described. First, as shown in FIG. 4, conductor films 13a and 13b made of a thin metal plate or the like are adhered to both surfaces of the substrate 4 having the through holes 6 formed at predetermined positions.

Next, the conductor films 13a and 13b are respectively etched to form circuit wirings 1A and 1B including connecting portions 1a and 1b on both surfaces of the substrate 4. At this time, the tongue 2
And the guide hole 5 are also formed at the same time.

As described above, according to this embodiment, since the leads 3 are supported by the elastic force of the tongue-shaped projections 2, the electrical connection between the circuit wirings 1A and 1B is maintained. However, it is possible to slide in a direction perpendicular to the substrate 4 and move in a direction parallel to the substrate 4.

Therefore, the thermal expansion difference between the lead 3 and the substrate 4
Alternatively, it is possible to adapt to displacement of the lead 3 in any direction due to external force or the like. For this reason, the connection between the circuit wirings formed on both sides of the printed board can be surely maintained as compared with a conventional printed board that can only receive the displacement of the lead 3 in the direction perpendicular to the board.

Since the leads 3 are supported by the resiliency of the tongue-shaped projections 2, the circuit wirings 1A and 1B disposed on both sides of the substrate 4 are connected by inserting the leads 3 into the guide holes 5. It only needs to. For this reason, the assembly work becomes easy,
Assembly time can be reduced.

Further, the connection portions 1a and 1b are
Since the entire portion covering both open ends is elastically deformed, it is possible to sufficiently receive the displacement of the lead 3 even at a connection portion having a smaller size than a conventional printed circuit board. Therefore, the space for the connection portion on the printed circuit board can be reduced.

The present invention is not limited to the above embodiment. For example, in the present embodiment, the connection unit 1
The tongue-shaped protrusions 2 formed on a and 1b are formed in a planar shape. However, as shown in FIG. Tongue 2
Can support the lead 3. In this case, the area of the contact portion between the lead 3 and the tongue-shaped projection 2 increases, and even when the displacement of the lead 3 is large, the connection portions 1a and 1b can receive the displacement of the lead 3.

Further, as shown in FIG. 6, the tongue-shaped projection 2 is deformed into a shape folded back to the outside of the through-hole 6, so that the deformed tongue-shaped projection 2 supports the lead 3. Is also possible. In this case, the deformed tongue 2
However, the lead 3 functions as a guide when the lead 3 penetrates the through-hole 6, and the mounting of the lead 3 on the substrate 4 becomes smooth,
Assembly time can be reduced.

When the tongue 2 is deformed as described above,
The tongue-shaped projection 2 can be bent or folded not only toward the outside of the through hole 6 but also toward the inside of the through hole 6. It is also possible to deform one tongue 2 toward the outside of the through hole 6 and deform the other tongue 2 toward the inside of the through hole 6, and vice versa. is there.

[0036]

According to the printed circuit board of the present invention described above, since the plurality of tongue-shaped projections receive the displacement of the wire, the connection between the first circuit wiring and the second circuit wiring is changed by temperature change or the like. Thus, a printed circuit board that can be reliably maintained regardless of the above is obtained. Further, a printed circuit board requiring a small space for connecting portions of circuit wiring can be obtained.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a connection portion of a circuit wiring provided on a surface of a printed circuit board according to an embodiment of the present invention and a cross section thereof.

FIG. 2 is a cross-sectional view of a connection portion of a circuit wiring provided on both surfaces of a printed circuit board according to the embodiment of the present invention.

3A is a diagram for explaining an operation of a printed board when displacement between a lead and a board occurs in a direction perpendicular to the board, and FIG. FIG. 9 is a diagram for explaining an operation of the printed circuit board when a displacement in a direction parallel to the board occurs between the steps.

FIG. 4 is a diagram for explaining a method of forming connection portions of circuit wirings provided on both sides of a printed circuit board according to the embodiment of the present invention.

FIG. 5 is a diagram showing a modification of the embodiment of the present invention.

FIG. 6 is a diagram showing another modified example of the embodiment of the present invention.

FIG. 7 is a perspective view for explaining a conventional printed circuit board.

FIG. 8 is a cross-sectional view for explaining a conventional printed circuit board.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1A circuit wiring 1B circuit wiring 1a connecting part 1b connecting part 2 tongue-shaped protrusion 3 lead 4 substrate 5 guide hole 6 through hole 7 lead 8 through hole 11a connecting part 11b connecting part 12 substrate 13a conductive film 13b conductive film

Claims (5)

[Claims] An insulating substrate having a through hole; a first circuit wiring provided on one surface of the substrate; and a second circuit wiring provided on the other surface of the substrate. The first circuit wiring and the second circuit wiring, which are connected to the first circuit wiring, are formed so as to cover at least a part of one opening end of the through hole, and are inserted into the through hole. A plurality of first tongue-shaped projections for holding a wire for connecting the first through-hole and the second circuit wiring, and formed so as to cover at least a part of the other open end of the through-hole; A plurality of second tongue-shaped projections for holding the wire inserted into the printed circuit board. 2. The plurality of first plurality of first electrodes inserted into the through holes.
2. The wire according to claim 1, further comprising a wire held by the tongue-shaped protrusions and the plurality of second tongue-shaped protrusions, and connecting the first circuit wiring and the second circuit wiring. 3. Printed board. 3. The plurality of first tongue-shaped protrusions and the plurality of second tongue-shaped protrusions are formed of an inverted fan-shaped conductor film, and the tips of the plurality of first tongue-shaped protrusions and the plurality of first tongue-shaped protrusions are formed. 3. The printed circuit board according to claim 1, wherein a tip end of the tongue-shaped protrusion holds the wire. 4. 4. The plurality of first tongue-shaped protrusions and the plurality of second tongue-shaped protrusions are curved to the outside or the inside of the through-hole, and have a side surface portion of the plurality of first tongue-shaped protrusions. 3. The printed circuit board according to claim 1, wherein side surfaces of the plurality of second tongue-shaped projections hold the wire. 4. 5. The plurality of first tongue-shaped protrusions are formed by folding back, the first protrusions covering at least a part of one opening end of the through hole, and the plurality of second tongue-shaped protrusions. A second projection formed by folding the projection to cover at least a part of the other opening end of the through hole; and a tip of the first projection and a tip of the second projection. The printed circuit board according to claim 1, wherein the printed circuit board holds the wire.