JP2002084629A - Circuit substrate and junction box therewith - Google Patents

Abstract

PROBLEM TO BE SOLVED: To increase the quality accuracy of a circuit substrate used for an internal circuit in a junction box. SOLUTION: The circuit substrate 18, in which a bus bar 17 is molded out of an insulation resin J, is used in the internal circuit stored in the junction box. The band-shaped circuit section 17b of the bus bar 17 is formed with a downwardly protruding section 17d to increase the rigidity of the bus bat itself for the prevention of the bus bar 17 from being deformed, at injection and increase a contact area with the resin J, thereby preventing the bus bar 17 from being dislocated.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a circuit board and a junction box provided with the circuit board, and more particularly, to improving the quality accuracy of a circuit board for an internal circuit applied to a junction box or the like to be modularized. .

[0002]

2. Description of the Related Art With the rapid increase of electric components mounted on automobiles, the number of electric junction boxes for automobiles, especially the circuits accommodated in junction boxes, has rapidly increased. The number of points has increased significantly, and the number of assembly steps has also increased.

In a junction box 1 shown in FIG. 7 of the electric connection box for automobiles, bus bars 5A to 5D are stacked and arranged between upper case 2 and lower case 3 with insulating plates 4A to 4E interposed therebetween. Upper case 2
Is provided with a connector housing 2a, a relay housing 2b, and a fuse housing 2c, and a connector 6, a relay 7, and a fuse 8 are mounted in these housings, and these terminals and the terminals protruding from the bus bar are directly or directly connected to each other. They are connected via relay terminals. The lower case 3 is also provided with a connector accommodating portion 3a, and the terminal 5a of the bus bar is protruded and connected to the connector.

[0004]

In the junction box 1, there is a problem that the area of the bus bar and the number of laminations increase as the number of circuits increases, and the junction box becomes large. When a connector housing, a relay housing, and a fuse housing are provided in both the upper case and the lower case, and the connector, relay, fuse and the internal circuit are connected to the upper and lower surfaces of the junction box, the upper case or It is possible to suppress an increase in the area of the junction box as compared with a case where the junction box is provided only on one side of the lower case.

However, if the connector accommodating portion and the relay accommodating portion or the fuse accommodating portion are provided at the upper and lower opposing positions, the terminals refracted by the bus bar overlap and cannot be deployed. Therefore, it is necessary to provide the terminal on the bus bar of another layer. This causes the number of layers to increase. As described above, when the number of stacked bus bars increases, the height of the junction box increases, and the size of the junction box increases.

Further, since the connector, the fuse, and the relay are connected to the bus bar in the junction box, if the specification of the connection between the fuse, the relay and the internal circuit is changed, the entire internal circuit is changed. And cannot easily cope with circuit changes.

In view of the above situation, if the bus bars connected to the connector, the relay, and the fuse are separately arranged in a region, it is possible to cope with an increase in the number of bus bar layers due to the overlap of terminals provided on the bus bar. Also, if the connector connection circuit section, the relay connection circuit section, and the fuse connection circuit section are each modularized, it is often possible to use the same even in different models and grades. Also, in the modules separated as described above, if the bus bars of each module are joined together by welding or the like, the bus bars are conductive and a required internal circuit can be formed.

[0008] The circuit in each of these modules may be a circuit in which an insulating plate and a bus bar are laminated on each other, or a circuit board in which the bus bar is molded with an insulating resin. is there.

As shown in FIG. 8A, generally, a molded circuit board 9 is formed by punching a conductive plate to form a band-shaped circuit portion 10b which is bent at a large number of places with a required width, and has an end portion. As shown in FIG. 8B, the bus bar 10 provided with the bent tab 10c is arranged inside a mold K for molding, and the resin is injected. Thus, a circuit board 9 in which the periphery of the bus bar 10 shown in FIG.

However, since the resin J is injected into the mold by applying a certain pressure to the injection of the resin J, the above-mentioned pressure is also applied to the bus bar 10 arranged in the mold.
Then, as shown in FIGS. 9 (A) and 9 (B), the circuit portion 10b of the bus bar 10 that has been subjected to the pressure is bent, causing a difference in the thickness of the resin J between the upper and lower portions of the bus bar 10, or the bus bar 10 having a regular thickness. There is a problem that the position is shifted. Also,
The circuit board 9 formed in this manner is connected to the bus bar 10.
However, there is also a problem that the resin J is easily deformed, the resin J is easily peeled off from the bus bar 10, or the internal stress remains in the bus bar 10, and the circuit board 9 is easily warped or bent.

Further, at the time of the injection molding, the busbar 10
Where the highest pressure is applied is the resin injection port Ka of the mold K.
Depending on the degree of deformation of the bus bar 10, the resin is difficult to spread in the mold, and a short shot, which is a defective phenomenon due to insufficient filling of the resin, may occur.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems, and a circuit in a junction box is modularized into a connector connection circuit section, a relay connection circuit section, and a fuse connection circuit section. It is an object of the present invention to suppress the increase in the number of stacked busbars accommodated in a semiconductor device, to reduce the thickness of the junction box, and to easily cope with a circuit change.
Another object is to prevent the busbar from being deformed during the injection molding of the circuit board to be molded, thereby preventing various problems.

[0013]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention is directed to a circuit board for molding a bus bar formed in a circuit shape with an insulating resin. Alternatively, there is provided a circuit board having a configuration in which a protrusion protruding downward is provided to improve the rigidity of the bus bar itself and increase the contact area with the resin.

As described above, when the convex portion is provided in the circuit portion of the bus bar, the bending rigidity and the like are improved as compared with the case of the flat plate shape,
Deformation of the bus bar can be prevented against the pressure at the time of resin injection. In addition, the convex portion increases the contact area with the resin, and the bus bar is stably held in the resin, so that displacement of the bus bar can be prevented.

The convex portion is provided at a position facing the resin injection port in the mold for molding a circuit board so that the projecting direction of the convex portion faces the injection port side. By providing the protrusions in this manner, the busbar having the highest rigidity can be disposed at the place where the injection pressure of the resin is most applied in the busbar, and the busbar can be most efficiently opposed to the injection pressure, and the deformation of the busbar can be reduced. It can be reliably prevented. Further, the resin injected from the injection port is diverted by the convex portion and smoothly filled in every corner of the mold, and the thickness of the resin becomes uniform at various places, thereby preventing occurrence of short shot.

A plurality of the convex portions are formed at intervals in the longitudinal direction of the circuit portion by bending the circuit portion. As described above, by providing a plurality of convex portions, the rigidity of the bus bar can be appropriately improved in accordance with the shape even in a complicated circuit shape. Further, the convex portion is formed such that a portion protruding from a part of the circuit portion in the width direction is continuous in the longitudinal direction. As described above, when the protrusions are formed continuously, the rigidity of the bus bar can be increased as a whole. The projections may be formed in various shapes other than the above shapes, such as projections, or may be mixed with various shapes.

According to the present invention, there is provided a junction box provided with the circuit board, wherein the junction box is divided into a connector connection circuit section, a fuse connection circuit section, and a relay connection circuit section housed in an upper case and a lower case. Then, the connector module, the fuse module, and the relay module are separately provided, and the ends of the bus bars of the respective modules are protruded to be welded portions, and the welded portions of the fuse module and the relay module are overlapped with the welded portions of the connector modules. Each module is joined by welding together, and a junction box is provided, wherein the circuit board is used for at least one of the modules.

As described above, the circuit in the junction box is divided into a connector connection circuit section, a relay connection circuit section, and a fuse connection circuit section, and each is separately provided as a connector module, a fuse module, and a relay module. That is, a bus bar for a circuit board for connector connection, a bus bar for a fuse circuit board, and a bus bar for a relay circuit board are provided separately.

Conventionally, one conductive plate is punched out to provide a connector connection circuit, a fuse connection circuit, and a relay connection circuit, and a tab for connector connection is provided on each of the circuit portions.
The provision of a tab for connecting a fuse and a tab for connecting a relay complicate circuit layout, resulting in an increase in the area of the bus bar and an increase in the number of bus bars.

On the other hand, according to the present invention, the bus bar for the connector, the bus bar for the fuse, and the bus bar for the relay are divided, punched out from separate conductive plates, and arranged at different positions. In addition, since the circuit layout of each bus bar is simplified, the bus bar area can be reduced, and the required internal circuit can be formed by welding and joining the bus bars of each module. In addition, by using a circuit board made of a bus bar having the above-described convex portion for at least one of these modules, a circuit for each module can be formed and the quality can be improved.

[0021]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows a disassembled state of a modularized junction box 11 according to the first embodiment of the present invention. Junction box 11
Divides an internal circuit accommodated in the upper case 11a and the lower case 11b into a connector connection circuit section, a fuse connection circuit section, and a relay connection circuit section, and modularizes them into a connector module 12, a fuse module 13, and a relay module 14. .

In each of the above modules, an internal circuit is formed by a circuit board in which a bus bar is molded with an insulating resin.
A weld is projected from each circuit board to join each module. For example, the connector module 12 forms a required circuit by superposing and welding the projecting fuse welding portion 15a with the welding portion 16a of the fuse module 13 and joining the modules. Similarly, a welding portion 15b for the relay projecting from the connector module 12 and a welding portion 17a of the relay module 14
Also overlap welding.

In this way, the circuit portion for the connector and the circuit portion for the fuse and the relay are electrically connected to each other, so that the modules are arranged without interference from each other, and the junction is increased without increasing the number of layers. It forms the necessary internal circuits for the box.

FIGS. 2A and 2B show the relay module 1.
4 shows a circuit board 18, which is formed by molding a resin J on a bus bar 17 composed of a band-shaped circuit portion 17b formed by punching a conductive plate into a circuit shape. As shown in FIG. 3A, the bus bar 17 is
A plurality of convex portions 17d that bend b and project downward are formed at required intervals. Also, the plurality of projections 17d
As shown in FIG. 3 (B), one of them is positioned opposite to the resin injection port Ka provided in the mold K for molding so that the projecting direction is directed toward the injection port Ka. Provided.

The bus bar 17 has a welded portion 17a formed by bending the end of the circuit portion 17b. In addition,
The projections 17d of the bus bar 17 do not necessarily need to be entirely protruded downward. Considering the circuit shape and the flow of resin in the mold, some of the projections 17d are formed as shown in FIG. The portion 17d 'may project upward. Also,
In addition, all the protrusions may be projected upward, and further, when the resin injection port is provided in the upper mold, only the protrusion facing the injection port is provided upward. It may be.

The bus bar 17 is arranged inside the mold K, and the insulating resin J is injected into the mold K in this state. At this time, as shown in FIG. 3 (B), the pressure accompanying the injection is applied to the convex portion 17d facing the injection port Ka of the bus bar 17, but the bus bar 17 is improved in bending rigidity and the like by the convex portion 17d. Is not deformed. The injected resin J is also dispersed by the convex portions 17d and smoothly flows to every corner of the mold. As shown in FIG. 5, the circuit portion 17b of the bus bar 17, which is opposite to the surface from which the resin is injected, is made of gold in order to make the positioning of the bus bar 17 more accurate and to withstand a larger injection pressure. Type K
May be supported by the ejector pin Kb provided at the end.

As shown in FIG. 2B, in the circuit board 18 molded in this manner, the bus bars 17 are not deformed, so that the thickness of the resin J is equal on the upper and lower sides of the bus bar 17. The bus bar 17 is in a regular position without displacement, and the holding force of the bus bar 17 is improved by the convex portion 17d, and the resin does not peel off.

The shape of the projection is not limited to the above embodiment. For example, as shown in FIG. 6 (A), the center of the bus bar 27 which is a part of the circuit portion 27b in the width direction is formed. A projecting portion may be formed by connecting a portion protruding upward in the longitudinal direction, and a projection-like projection is formed on a part of the circuit portion 37b of the bus bar 37 as shown in FIG. The protrusion 37d may be provided so as to protrude. Furthermore, these various shapes of convex portions may be mixed with various shapes of convex portions on each bus bar when a circuit board is formed by arranging a plurality of separated bus bars in the same mold. Also, various shapes of projections may be mixed in a single bus bar.

Further, the circuit board formed as described above is applied not only to the relay module 14 but also to the connector module 12 and the fuse module 13. In addition, the above-mentioned circuit board can of course be applied to an internal circuit of a junction box that is not modularized.

[0030]

As is apparent from the above description, when the circuit board according to the present invention is used, since the bus bar is provided with the convex portion, the rigidity of the bus bar itself is improved.
The resin is molded evenly, the bus bar is securely held, the displacement of the bus bar is eliminated, and the productivity of the circuit board can be ensured. Also, by dividing the internal circuit of the junction box for each electric component and forming a module, it is possible to prevent the junction box from increasing in size, easily respond to circuit changes, and use the above circuit board for each module. Also, the quality of each module can be stabilized.

[Brief description of the drawings]

FIG. 1 is an exploded perspective view of a modularized junction box according to the present invention.

2A is a perspective view of a circuit board according to the present invention, and FIG. 2B is a cross-sectional view of the circuit board.

FIG. 3A is a perspective view of a bus bar of a circuit board,
(B) is a schematic diagram at the time of molding in a mold.

FIG. 4 is a perspective view of a bus bar according to a modification.

FIG. 5 is a schematic diagram at the time of molding in another modified example.

FIGS. 6A and 6B are perspective views of another modified bus bar.

FIG. 7 is an exploded perspective view of a conventional junction box.

8A is a perspective view of a bus bar, FIG. 8B is a schematic view at the time of molding, and FIG. 8C is a perspective view of a molded circuit board.

FIGS. 9A and 9B are schematic diagrams showing problems.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 11 Junction box 12 Connector module 13 Fuse module 14 Relay module 15a, 15b, 16a, 17a Welding part 17 Bus bar 17b Circuit part 17d Convex part 18 Circuit board J resin K Die Ka Injection Kb Ejector pin

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) H05K 7/06 H05K 7/06 A (72) Inventor Yuji Osaka 1-14 Nishisuehirocho, Yokkaichi-shi, Mie Prefecture Sumitomo Wiring Systems, Inc. F-term (reference) 5E338 AA03 AA16 BB75 CC01 CC10 CD05 EE26 EE31 5G361 BA04 BB02

Claims (5)

[Claims] 1. A circuit board for molding a bus bar formed into a circuit shape with an insulating resin, wherein a convex portion protruding upward and / or downward is provided on a band-shaped circuit portion of the bus bar, and A circuit board characterized by improving rigidity and increasing a contact area with a resin. 2. The method according to claim 1, wherein the projecting portion is provided at a position facing a resin injection port in a mold for molding a circuit board so that a projecting direction of the projecting portion is directed to the injection port side. The circuit board according to claim 1, wherein 3. The circuit board according to claim 1, wherein a plurality of the protrusions are formed at intervals in a longitudinal direction of the circuit portion by bending the circuit portion. 4. The circuit according to claim 1, wherein the projecting portion is formed such that a portion projecting from a part of the circuit portion in a width direction is continuous in a longitudinal direction. substrate. 5. The method according to claim 1, wherein
A junction box provided with a circuit board according to the item, wherein the junction box divides a connector connection circuit portion, a fuse connection circuit portion, and a relay connection circuit portion accommodated in an upper case and a lower case into a connector module and a fuse module. The relay module is provided separately as a relay module, and the ends of the bus bars of the respective modules are protruded to form welds, and the welds of the fuse module and the relay module are overlapped and welded to the welds of the connector module. Wherein the circuit board is used for at least one of the modules.