JP2001327041A - Wiring board - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a wiring board wherein poor weld between a bus bar and an electric wire is positively prevented. SOLUTION: Bus bars 25 and 26 are buried in insulating boards 23 and 24 so that part of the bus bars are exposed, and exposed portions 25b and 26b of the bus bars 25 and 26, exposed at the surfaces of the insulating board 23 and 24 and the connecting portion 37b of an electric wire 37 wired on the insulating board 23 and 24, are jointed with each other with a pair of electrodes 38 and 39 sandwiched in-between for welding to form a wiring board 21 and 22. In the wiring boards 21 and 22, connecting holes 33 and 34, larger in diameter than the individual electrodes 38 and 39, are formed around the exposed portions 25b and 26b of the bus bars 25 and 26 of the insulating boards 23 and 24, and the exposed portions 25b and 26b of the bus bars 25 and 26 are completely exposed in the connecting holes 33 and 34.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wiring board on which a plurality of bus bars and a plurality of electric wires are arranged in a matrix.

[0002]

2. Description of the Related Art FIGS. 10 to 12 show a laminated wiring board assembly in which such wiring boards are vertically stacked. As shown in FIG. 11, the laminated wiring board assembly 1 has a pair of insulating substrates 2 and 3 formed by insert molding a plurality of bus bars 4 at predetermined intervals in the width direction on a substantially flat surface at a predetermined distance. These insulating substrates 2 and 3 are arranged in parallel.
A plurality of electric wires 5 are laid so as to be bridged therebetween, and the plurality of electric wires 5 are linearly formed on the respective surfaces 2a, 3a of the pair of insulating substrates 2, 3 in the longitudinal direction substantially orthogonal to the bus bars 4. And a plurality of electric wires 5 between the pair of insulating substrates 2 and 3
11 are bent in the direction of arrow X in FIG. 11 and the back surfaces 2b and 3b of the pair of insulating substrates 2 and 3 are overlapped with each other.

As shown in FIG. 12, when the electric wire 5 is wired, the exposed portion 4a of the bus bar 4 at a predetermined position exposed from the pair of insulating substrates 2 and 3 crosses the exposed portion 4a of the bus bar 4. 5a of the wire 5 at a predetermined position routed in
Are joined between a pair of electrodes 7 and 8 for resistance welding.

As the electric wire 5, a bare electric wire without an insulating coating is used. A similar technique relating to the laminated wiring board assembly 1 is disclosed in Japanese Patent Application No. 10-308424.

[0005]

However, a pair of insulating substrates 2 and 2 that constitute the conventional laminated wiring board assembly 1 described above.
In FIG. 13, the electrodes 8 around the exposed portions 4a of the bus bars 4 on the back surfaces 2b and 3b of the insulating substrates 2 and 3 as shown in FIG.
When the resin burr B is generated in a portion where the exposed portion 4a hits, the electrode 8 and the exposed portion 4a of the bus bar 4 cannot be stably contacted, and the exposed portion 4a of the bus bar 4
There was a possibility that welding with the part 5a might be defective or welding could not be performed.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-described problem, and has as its object to provide a wiring board capable of reliably preventing a welding failure between a bus bar and an electric wire.

[0007]

According to a first aspect of the present invention, a bus bar is embedded in an insulating substrate so that a part of the bus bar is exposed, and an exposed portion of the bus bar exposed from the insulating substrate and a wiring on the insulating substrate. In a wiring board formed by sandwiching and joining the connected portion of the electric wire with a pair of welding electrodes, a connection hole having a diameter larger than the diameter of each electrode is formed around the exposed portion of the bus bar of the insulating substrate. The exposed portion of the bus bar is completely exposed in the connection hole.

In this wiring board, a connection hole having a diameter larger than the diameter of each electrode is formed around the exposed portion of the bus bar of the insulating substrate.
By completely exposing the exposed portion of the bus bar in the connection hole, the exposed portion of the bus bar and the connection portion of the wire are securely contacted between the pair of electrodes, and the exposed portion of the bus bar and the connection portion of the wire are connected to each other. Is reliably welded.

According to a second aspect of the present invention, in the wiring board according to the first aspect, the connection hole is formed in a rectangular shape, and the bus bar and the electric wire are routed so as to be substantially orthogonal to each other. The busbar and the electric wire are respectively arranged such that the exposed portion of the busbar and the connection portion of the electric wire are located substantially at the center of each side of the rectangular connection hole.

In this wiring board, the connection hole is formed in a rectangular shape, and the bus bar and the electric wire are routed so as to be substantially orthogonal to each other. The exposed portion of the bus bar is located substantially at the center of each side of the rectangular connection hole. Since the bus bar and the electric wire are routed so that the connection portion of the bus bar and the electric wire are located, the contact stability of the pair of electrodes with respect to the exposed portion of the bus bar and the connection portion of the electric wire is further improved. Is welded more reliably.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a perspective view showing a state before assembly of a laminated wiring board assembly according to an embodiment of the present invention, FIG. 2 is a plan view showing a state after assembly of the assembly, and FIG. FIG. 4 is a perspective view of the assembled state of the bus bar viewed from the back, FIG. 4 is a partial cross-sectional view showing the joined state of a bus bar and an electric wire of a bus bar wiring board used in the assembly, and FIG. FIG. 6 is a partial plan view showing a joint state between the bus bar and the electric wire, FIG. 7 is a partial bottom view showing a joint state between the bus bar and the electric wire, and FIGS. 8 (a) to 8 (e) FIG. 9 is a partial cross-sectional view showing the assembling process of the assembly in order, and FIG. 9 is an exploded perspective view of an electric junction box accommodating the assembly.

As shown in FIG. 9, the laminated wiring board assembly 20
Are made of a synthetic resin that forms the outer shape of the electric connection box 10 and are housed in box-shaped upper and lower cases 11 and 12. That is,
A busbar wiring board 15, in which terminals 14a, 14b of a plurality of busbars 14 are protruded in the upper and lower cases 11, 12 so as to be vertically symmetrical with respect to the laminated wiring board assembly 20,
16 and wiring sheets 18 and 19 in which a plurality of electric wires 17 are laid.
Are accommodated by arranging them. In addition,
Connector mounting parts 13A, 13B are provided in lower cases 11, 12, respectively.
Etc. are integrally formed.

As shown in FIGS. 1 and 8 (a), the laminated wiring board assembly 20 has a pair of busbar wirings arranged in parallel on substantially one plane with adjacent ends 21c and 22c abutting each other. Boards (wiring boards) 21 and 22 and the surfaces 21a and 22a of the pair of bus bar wiring boards 21 and 22 are laid so as to extend between the pair of bus bar wiring boards 21 and 22.
And a plurality of electric wires 37 routed respectively.
A bare electric wire without an insulating coating is used as the plurality of electric wires 37.

Each of the bus bar wiring boards 21 and 22 is an insulating substrate 2
A plurality of bus bars 25, 26 are formed by linear and parallel insert molding in the width direction of the
Tab terminals (terminals) 25a, 25
a, 26a, 26a are erected at the same height. Further, in the direction substantially orthogonal to the bus bars 25 and 26 on the surfaces of the insulating substrates 23 and 24, wire receiving portions 27 and 28 having a groove-shaped cross section are integrally formed. The electric wire housings 27 and 28 are formed from the surface of the insulating substrates 23 and 24 to the front and back surfaces of the adjacent ends, and are provided on both sides of the electric wire housings 27 and 28 at each end. Have insulating ribs 29 and 30 formed integrally with each other. Further, a pair of protrusions 27a, 27a, 28a, 2 as stoppers are provided on the opposing inner surfaces of the respective wire housings 27, 28.
8a are integrally formed at predetermined intervals so that the electric wires 37 accommodated in the electric wire accommodating portions 27, 28 are accommodated so as to be clamped between the pair of opposing projections 27a, 27a, 28a, 28a. The state is maintained.

Further, the end portions 21c and 22c of the pair of bus bar wiring boards 21 and 22 are integrally formed so as to protrude at the corners on the back surface side of the end portions 21c and 22c, that is, at the adjacent end portions of the insulating substrates 23 and 24. On the lower side of each of the insulating ribs 29 and 30, rounded portions 31 and 32 having a substantially arc-shaped surface are formed, respectively.
The adjacent round portions 31 and 32 are used to bend the connecting portion 37a of the plurality of electric wires 37 bridged between the pair of insulating substrates 23 and 24 to overlap the pair of insulating substrates 23 and 24 vertically. The contact is free.

Further, a part of the predetermined bus bars 25, 26 is exposed from each of the insulating substrates 23, 24. That is, FIG.
As shown in FIG. 7, a part of each bus bar 25, 26 of each insulating substrate 23, 24 becomes exposed portions 25b, 26b and is exposed on the front and back sides, and around each bus bar 2,
A pair of electrodes 3 for resistance welding which are joined by sandwiching the exposed portions 25b and 26b of the wires 5 and 26 and the connecting portion 37b of each electric wire 37.
Connection holes 33 and 34 having diameters larger than the diameters 8 and 39 are formed. The connection holes 33 and 34 are formed in a rectangular shape, and the exposed portions 25 b and 26 b of the bus bars 25 and 26 and the electric wires 37 are provided substantially at the centers of the sides of the rectangular connection holes 33 and 34.
Are arranged such that the connection portions 37b are located. As a result, the exposed portions 25b, 26b of the bus bars 25, 26 and the connecting portion 37b of the electric wire 37 are routed in the respective connecting holes 33, 34 so as to be substantially orthogonal to each other.
The exposed portions 25b and 26b of the bus bars 25 and 26 are completely exposed.

As described above, the connection holes 33 and 34 having a diameter larger than the diameter of the pair of electrodes 38 and 39 are formed around the exposed portions 25b and 26b of the bus bars 25 and 26 of the insulating substrates 23 and 24, respectively. Since the exposed portions 25b and 26b of the bus bars 25 and 26 are completely exposed in the connection holes 33 and 34, the bus bars 25 and 26 are provided between the pair of electrodes 38 and 39.
Can reliably contact the exposed portions 25b, 26b of the bus bars and the connecting portions 37b of the electric wires 37.
The exposed portions 25b, 26b can be securely joined to the connection portions 37b of the electric wires 37. In particular, each connection hole 3
Each of the busbars 25 and 26 and each of the electric wires 37 are routed so as to be substantially orthogonal to each other, and each of the busbars 25 and 26 and each of the electric wires 37 are arranged substantially at the center of each side of each of the connection holes 33 and 34 of this rectangle. Each bus bar 2 is positioned such that the exposed portions 25b and 26b of the bus bars 25 and 26 and the connection portion 37b of each electric wire 37 are located.
5 and 26 and the electric wires 37, respectively, so that the exposed portions 25b and 26b of the bus bars 25 and 26 and the electric wires 37
The contact stability of the pair of electrodes 38, 39 with the connection portion 37b of the bus bar 2 can be further improved.
The exposed portions 25b and 26b of the wires 5 and 26 and the connecting portions 37b of the electric wires 37 can be more reliably joined.

Incidentally, as shown in FIG.
Curved portions 27b and 28b curved in an arc shape are formed at the boundaries between the connection holes 28 and the connection holes 33 and 34, respectively, so that the electric wires 37 can contact the curved portions 27b, 27b, 28b and 28b without gaps. It has become.

Further, as shown in FIGS. 1 and 3, the bus bars 26 and the electric wires 37 routed on the insulating substrate 24 located on the back side at the time of completion of the assembly are routed so as to avoid substantially the center of the insulating substrate 24. Have been. Then, the insulating substrate 24
A substantially rectangular hole 35 is formed at a substantially central portion where the bus bars 26 and the electric wires 37 are not routed.

When assembling the laminated wiring board assembly 20 of the above embodiment, first, as shown in FIGS. 1 and 8 (a), a pair of bus bar wiring boards 21 and 22 are connected to each adjacent end 21c, The pair of busbar wiring boards 21 and 22 are arranged in parallel on substantially one plane in a state where the pair of busbars 22c are abutted with each other.
Each wire accommodating portion 27, 28 formed so as to be laid so that a plurality of wires 37 are bridged therebetween and linearly connected to the surfaces 21 a, 22 a of the pair of bus bar wiring boards 21, 22.
Accommodate the electric wires 37 respectively. At this time, the electric wires 37 accommodated in the electric wire accommodating portions 27 and 28 are held between the pair of opposing projections 27a, 27a, 28a and 27a, respectively. In addition, there is an electric wire 37 that is accommodated only in the electric wire accommodating portion 27 of the one bus bar wiring board 21 and is not routed on the surface 22a of the other bus bar wiring board 22. 28, each surface 21a, 22 of each bus bar wiring board 21, 22
It does not protrude from a.

Next, as shown in FIGS. 4 to 7, the adjacent ends 21c and 22 of the pair of bus bar wiring boards 21 and 22 are connected.
c with the busbar wiring boards 2
A pair of electrodes 3 for resistance welding are formed by connecting the exposed portions 25b, 26b of the bus bars 25, 26, which are partially exposed from the insulating substrates 23, 24 forming the first and second 22, and the connection portions 37b of the electric wires 37.
Join through 8,39. As a result, the electric wires 37 are securely held in the electric wire housings 27 and 28, and as shown in FIG. 1, the pair of bus bar wiring boards 21 and 22 having the ends 21c and 22c abutted are substantially flat. become.

From this state, as shown in FIGS. 8 (b) to 8 (d), the bridging portion 37a of each electric wire 37 located between the pair of bus bar wiring boards 21 and 22 is bent. At this time, the corners on the back surfaces 21b, 22b side of the butted ends 21c, 22c of the pair of bus bar wiring boards 21, 22, that is, the respective arc-shaped rounds under the insulating ribs 29, 30. While the portions 31, 32 contact each other, the crossover portion 37a of each electric wire 37 becomes a hinge and the other busbar wiring board 22
Can be inverted with respect to one bus bar wiring board 21, and as shown in FIGS. 8 (a) to 8 (e),
Back surfaces 21b and 22 of a pair of bus bar wiring boards 21 and 22
b, the transfer portion 37a of each electric wire 37 until they are superimposed.
Is bent while being housed in the wire housings 27, 28 formed from the front side to the back side of the end portions 21c, 22c, so that when the bridge 37a of the wire 37 is bent, the wire 37 The extension of the portion 37a is suppressed, so that no extra tension is generated in each electric wire 37, and the exposed portions 25b, 26 of the bus bars 25, 26 are not generated.
No load is applied to the joint between the wire b and the connecting portion 37b of each electric wire 37. Thereby, the joining state between the exposed portions 25b, 26b of the bus bars 25, 26 and the connecting portions 37b of the electric wires 37 can be stabilized, and the bus bars 25, 26 can be stabilized.
It is possible to reliably prevent the occurrence of connection failure between the cable and the electric wire 37.

Then, as shown in FIGS. 3 and 8 (e),
The crossover portion 37a of each electric wire 37 between the pair of busbar wiring boards 21 and 22 is bent substantially 180 degrees, and the back surfaces 21b and 22b of the pair of busbar wiring boards 21 and 22 are overlapped with each other to form the laminated wiring board assembly 20. Is completed. At this time, the crossover portion 37a of each electric wire 37 bent into a U-shape
Are completely accommodated in the respective wire accommodating portions 27, 28 of the butted ends 21c, 22c. In addition, each electric wire 37
The creeping distance of the crossover portion 37a bent into a U-shape by the insulating ribs 29, 29, 30, and 30 protruding on both sides of the wire housing portions 27 and 28 on the end portions 21c and 22c side, respectively. Sufficiently secured. With these, each electric wire 37
Each of the crossover portions 37a, 3b which are bent into a U-shape
Short circuit and leak between 7a can be reliably prevented.

As described above, the pair of bus bar wiring boards 21 and
In a state where the adjacent end portions 21c, 22c of the 22 are abutted, each of the round portions 31, 32 of the end portions 21c, 22c.
Each connecting portion 37a of the plurality of electric wires 37 while abutting each other
By simply folding the pair of bus bar wiring boards 21 and 22 up and down, a high-quality multilayer wiring board assembly 20 having no short circuit or leak between the electric wires 37 and 37 can be assembled easily and in a large amount in a short time. be able to. In particular,
Adjacent ends 21 of a pair of bus bar wiring boards 21 and 22
c, 22c, each insulating substrate 2
Exposed portion 2 of each bus bar 25, 26 exposed from 3, 24
5b, 26b and the connecting portion 37b of each electric wire 37 are joined by resistance welding, and thereafter, the bridging portion 37a of each electric wire 37 is bent and completely accommodated in each electric wire housing portion 27, 28. A high-quality multilayer wiring board assembly 20 having no poor connection between the wires 25 and 26 and the electric wires 37 can be assembled in a large amount simply and in a short time.

According to the above embodiment, the lightening hole for preventing warpage is formed only in the bus bar wiring board on the back side.
A lightening hole for preventing warpage may also be formed in the busbar wiring board on the front side. In addition, it is a matter of course that the lightening formation may be a hole shape that does not penetrate. Further, the connection hole between the exposed portion of the bus bar into which the electrode for resistance welding is inserted and the connection portion of the electric wire is not limited to a square but may be a circle or an ellipse.

[0027]

As described above, according to the first aspect of the present invention, a connection hole having a diameter larger than the diameter of each electrode is formed around the exposed portion of the bus bar of the insulating substrate. By completely exposing the exposed portion of the busbar to the exposed portion of the busbar, the exposed portion of the busbar and the connection portion of the wire can be reliably brought into contact between the pair of electrodes, and the exposed portion of the busbar and the connection portion of the wire can be securely connected. Can be welded.

According to the second aspect of the present invention, the connection hole is formed in a rectangular shape, and the bus bar and the electric wire are routed so as to be substantially orthogonal to each other. Since the busbar and the electric wire are respectively routed so that the exposed portion of the busbar and the connection portion of the electric wire are located, the contact stability of the pair of electrodes with respect to the exposed portion of the busbar and the connection portion of the electric wire can be further improved. Thus, the exposed portion of the bus bar and the connection portion of the electric wire can be more reliably welded.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a state before assembling a laminated wiring board assembly according to an embodiment of the present invention.

FIG. 2 is a plan view showing a state after assembly of the laminated wiring board assembly.

FIG. 3 is a perspective view of a state after assembling the laminated wiring board assembly as viewed from the back side.

FIG. 4 is a partial cross-sectional view showing a joining state of a bus bar and an electric wire of a bus bar wiring board used in the laminated wiring board assembly.

FIG. 5 is a partial longitudinal sectional view showing a joining state of a bus bar and an electric wire of the bus bar wiring board.

FIG. 6 is a partial plan view showing a joining state of a bus bar and an electric wire of the bus bar wiring board.

FIG. 7 is a partial bottom view showing a joining state of a bus bar and an electric wire of the bus bar wiring board.

FIGS. 8A to 8E are partial cross-sectional views sequentially showing an assembling process of the laminated wiring board assembly.

FIG. 9 is an exploded perspective view of an electric junction box accommodating the laminated wiring board assembly.

FIG. 10 is a perspective view of a conventional laminated wiring board assembly.

FIG. 11 is a perspective view showing a state before assembly of the conventional laminated wiring board assembly.

FIG. 12 is a partial cross-sectional view showing a joining state of a bus bar and an electric wire of a bus bar wiring board used in the conventional laminated wiring board assembly.

FIG. 13 is a partial cross-sectional view showing a problem when a bus bar and an electric wire of a bus bar wiring board used in the conventional laminated wiring board assembly are joined.

[Explanation of symbols]

 21, 22 bus bar wiring board (wiring board) 23, 24 insulating substrate 25, 26 bus bar 25b, 26b exposed portion 33, 34 connection hole 37 electric wire 37b connection portion 38, 39 pair of electrodes

Claims (2)

[Claims] A busbar is buried in an insulating substrate so that a part of the busbar is exposed, and an exposed portion of the busbar exposed from the insulating substrate and a connection portion of an electric wire routed on the insulating substrate are welded. In a wiring board formed by being sandwiched between a pair of electrodes, a connection hole having a diameter larger than the diameter of each of the electrodes is formed around an exposed portion of the bus bar of the insulating substrate, and the bus bar is formed in the connection hole. A wiring board characterized by completely exposing the exposed portion of the wiring board. 2. The wiring board according to claim 1, wherein the connection hole is formed in a rectangular shape, and the bus bar and the electric wire are routed so as to be substantially orthogonal to each other. A wiring board, wherein the bus bar and the electric wire are respectively arranged such that an exposed portion of the bus bar and a connection portion of the electric wire are located substantially at the center of each side of the wiring board.