JP2001327045A - Wiring board - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a wiring board the warpage of which can be prevented. SOLUTION: A plurality of bus bars 26 are buried in an insulating board 24 in a prescribed direction, and a plurality of electric wires 37 are installed on the insulating board 24 in the direction which crosses the specified direction to form a wiring board 22. The insulating board 24 is cut out at a place, where neither the bus bars 26 nor the electric wires 37 are installed. More specifically, the bus bars 26 and the electric wire 37 are installed on the insulating board 24 at places other than its substantially central portion, and the substantially central portion of the insulating board 24 is cut out to form a hole 35 in a prescribed shape. Warpage in the insulating board 24 is effectively prevented by the hole 35 in this prescribed shape.

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, the insulating substrates 2 and 3 constituting the conventional laminated wiring board assembly 1 are:
Since the plurality of bus bars 4 are insert-molded at predetermined intervals only in one direction in the width direction, the bus bars 4 easily warp, which hinders the assembling work.

Accordingly, the present invention has been made to solve the above-mentioned problem, and has as its object to provide a wiring board capable of preventing the occurrence of warpage.

[0007]

According to a first aspect of the present invention, a plurality of bus bars are respectively buried in an insulating substrate in a predetermined direction, and a plurality of electric wires are respectively arranged on the insulating substrate in a direction intersecting the predetermined direction. In the wiring board formed by the cable, portions where the bus bars and the electric wires of the insulating substrate are not respectively routed are formed to be lightened.

In this wiring board, the portions of the insulating substrate where the plurality of bus bars and the plurality of electric wires are not respectively routed are lightened and formed. The occurrence of substrate warpage is prevented.

According to a second aspect of the present invention, there is provided the wiring board according to the first aspect, wherein each of the bus bars and each of the electric wires are routed so as to avoid a substantial center of the insulating substrate, and a substantially central portion of the insulating substrate is provided. A hole having a predetermined shape is formed as the lightening.

In this wiring board, a plurality of bus bars and a plurality of electric wires are respectively routed around a substantially center of the insulating substrate, and a hole having a predetermined shape is formed at a substantially central portion of the insulating substrate. The holes having a predetermined shape can reduce the weight of the insulating substrate and the cost of materials, and shorten the molding cycle.

[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 shown in FIG. 4, curved surface portions 27b and 28b curved in an arc shape are formed at the boundaries between the electric wire accommodating portions 27 and 28 and the connection holes 33 and 34, respectively. 27b, 28
The wires 37 abut on the b and 28b without any gap.

Further, as shown in FIGS. 1 and 3, the bus bars 26 and the electric wires 37 routed to the insulating substrate 24 located on the back side when the assembly is completed 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.

As described above, the plurality of bus bars 26 and the plurality of electric wires 37 routed on the insulating substrate 24 are
Are routed so as to avoid substantially the center of the
Since the substantially rectangular holes 35 are formed in the substantially central portions where the busbars 26 and the electric wires 37 of No. 4 are not routed, the warpage of the insulating substrate 24 is effectively reduced by the substantially rectangular holes 35. It is possible to suppress the occurrence of warpage of the insulating substrate 24. Thus, the laminated wiring board assembly 20 can be completed by easily assembling the insulating substrate 24 to the insulating substrate 23 side. In addition, the substantially rectangular hole 35 formed at the substantially central portion of the insulating substrate 24 can reduce the weight and material cost of the insulating substrate 24 and shorten the molding cycle. .

When assembling the laminated wiring board assembly 20 of the above embodiment, first, as shown in FIGS. 1 and 8 (a), a pair of busbar 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 clamped between the pair of opposing projections 27a, 27a, 28a and 28a, 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, 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,
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-described embodiment, a 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.

[0026]

As described above, according to the first aspect of the present invention, portions where the plurality of bus bars and the plurality of electric wires are not routed are formed in the insulating substrate. The warpage of the insulating substrate can be effectively suppressed, and the warpage of the insulating substrate can be prevented.

According to the second aspect of the present invention, a plurality of bus bars and a plurality of electric wires are respectively routed around the substantially central portion of the insulating substrate, and a hole having a predetermined shape is formed at a substantially central portion of the insulating substrate. Thus, the holes having the predetermined shape can reduce the weight of the insulating substrate and the cost of material, and can shorten the molding cycle.

[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.

[Explanation of symbols]

 Reference Signs List 22 busbar wiring board (wiring board) 24 insulating board 26 busbar 35 hole of predetermined shape (lightening) 37 electric wire

Claims (2)

[Claims] 1. A wiring board comprising a plurality of bus bars embedded in an insulating substrate in a predetermined direction and a plurality of electric wires routed on the insulating substrate in a direction intersecting the predetermined direction. A wiring board, wherein portions where the busbars and the electric wires are not routed are cut out. 2. The wiring board according to claim 1, wherein each of the busbars and each of the electric wires are routed around a substantially center of the insulating substrate, and the hollow is formed at a substantially central portion of the insulating substrate. A wiring board, wherein a hole having a predetermined shape is formed.