JPH0458253B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a waterproof structure of a junction box (hereinafter referred to as "JB") used for connecting a wire harness.

Prior Art The conventional waterproof seal structure of JB installed in automobiles, etc. has a structure as shown in Figs. 6 and 7.

That is, reference numeral 1 denotes a waterproof case, which is fitted with a main body case 2 having a connecting portion 2a to a wire harness via a rubber packing 3, and has a structure that easily prevents water from entering. Reference numeral 4 denotes a lid case, which fits into the main case 2 and houses internal electronic components such as a fuse 5a, a relay 5b, and an electronic unit 5c.
Protect and fix etc. Reference numeral 6 denotes a busbar circuit having a desired pattern, and tab-shaped terminals (not shown) for external connection coupled to this busbar circuit make electrical connections with the electronic components 5a to 5c and the wire harness. 7 is an insulating substrate made of synthetic resin, and J.
When assembling B, the busbar circuit 6 is positioned and insulated, and the busbar circuit 6 is
Together, they form a busbar wiring board A. 8 is filled resin 9 filled without any gap between the upper and lower insulating substrates.
It is a rubber packing (rubber plate) for preventing sagging, and also serves as a waterproof seal with the main body case 2.

Problems to be Solved by the Invention In the conventionally known technology described above, the connection between the fitting surfaces of the cases 1, 2, and 4 constituting the outer shell of the JB and the bus bar wiring board accommodated inside the case is limited. It is necessary to interpose rubber packings 3, 8, etc., and there is a risk that the waterproof performance will deteriorate due to an increase in the number of parts and aging of the packings.

On the other hand, with laminated busbar wiring boards, resin must be filled between each insulating board without any gaps, so J.
After completing the assembly of B, epoxy resin, grease, etc. are injected under pressure into the interior through the injection port 10 provided in the lid case 4, suction is applied to remove internal air bubbles, and heat treatment (heating or It requires various processes such as cooling), and must be carried out on a separate line from JB's assembly line.
In addition to high production costs, resin filling increased the weight of the JB.

The purpose of the present invention is to solve the above problems and to
The object of the present invention is to provide a waterproof structure for JB that can be easily and quickly achieved at reduced cost without increasing the overall weight or number of parts.

Means for Solving the Problems In order to achieve the above object, the JB according to the present invention
The waterproof structure consists of stacking a plurality of bus bars and an insulating substrate in multiple layers, each having a desired pattern and having tab-shaped terminals facing upward or downward at the ends or in the middle, and connecting the tab-shaped terminals to each other in a plurality of layers. A laminated busbar wiring board protruding from an insertion hole provided in an insulating substrate to the top layer or the bottom layer is housed between a lid case and a main body case, and the tab-shaped terminal group is provided in the lid case or the main body case. In the junction box, which is formed by protruding into a connecting part for an external connector, etc., and whose lid case is covered with a waterproof cover, one surface of two opposing insulating substrates sandwiching a busbar circuit in the laminated busbar wiring board. is provided with a busbar mounting groove for the busbar circuit, so that the two opposing insulating substrates are brought into close contact with each other during the stacking process, and the other surface is provided with a busbar mounting groove for easy infiltration of an organic solvent. In addition, the insertion hole of the insulating substrate is formed in such a size that it comes into close contact with the outer periphery of the tab-shaped terminal when the tab-shaped terminal is inserted, and the insertion hole of the insulating substrate is formed in such a size that it comes in close contact with the outer periphery of the tab-shaped terminal when the tab-shaped terminal is inserted. Between the holes, between the vertically opposing insulating substrates constituting the laminated busbar wiring board, and between the fitting parts of the main body case and the lid case constituting the outer shell of the junction box. It is characterized by being welded and sealed using an organic solvent, and the welding and sealing process using an organic solvent is extremely simple, such as injecting or spraying the organic solvent onto the fitting part of the case, or immersing it in the solvent for a short time and then pulling it up and drying it. This can be achieved by various methods.

Embodiment In FIG. 1, the busbar circuit 6 is connected to an insulating substrate 7.
The busbar wiring boards A arranged in the main body case 2 and the lid case 4 are stacked as shown in
The tab-shaped terminals 11 connected to the busbar circuits 6 are passed through the insertion holes 7a of each insulating substrate 7 and protruded from the top or bottom layer of the laminated busbar wiring board B. , the tip thereof is guided to a joint part 4a formed integrally with the lid case 4, and after passing through an insertion hole provided similarly to the insulating board, it is relayed here to the electronic components 5a to 5c (see FIG. 6). The connection is made via the female terminal 12.

The above configuration is the same as the conventional one, but in the present invention, the fitting parts of each case 1, 2, 4, the insertion hole 7a of the tab-shaped terminal, and the waterproof seal between each insulating substrate in the laminated busbar wiring board B are made using an organic solvent. This is done by welding using.

That is, shallow grooves 13 are provided in the form of veins on one or both surfaces of each insulating substrate 7, and concave portions are provided at the edges of each insulating substrate 7, so that an organic solvent injection port is provided when the insulating substrates 7 are laminated. 14 (Figure 2)
It is configured to form a The busbar wiring board A has a busbar circuit on the top surface of the insulating substrate 7 ₁ so that the upper and lower insulating substrates 7 ₁ and 7 ₂ are in close contact with each other as shown in FIG. 3 when these are stacked together. Either bus bar mounting grooves 15 having a pattern are provided in advance, or bus bar fitting grooves (not shown) corresponding to the lower surface of the upper insulating substrate ₇₂ to be superimposed are provided in advance. This eliminates the level difference between the insulating substrate and the busbar circuit.

When an organic solvent is injected from an injector 16 like a syringe through an inlet 14 of a laminated busbar wiring board, minute gaps and vein-shaped grooves 13 between each insulating substrate are formed.
Further, the organic solvent infiltrates through the gap between the busbar circuit 6 and its mounting groove 15 due to capillary action and spreads to every corner. That is, by providing the vein-shaped grooves 13 on one or both sides of the insulating substrate 7, even if the busbar circuit 6 or the mounting groove 15 is interposed in the middle, the organic solvent does not stop permeating there and spreads over the entire surface. . Then, the organic solvent dissolves a part or all of the surface of the insulating substrate, and as a result of the evaporation, the insulating substrates adhere to each other, so to speak, and are welded to form a sealed state. Similarly, the busbar circuit 6 is also covered and fixed with melted resin, so that it is sealed. Furthermore, the tab-shaped terminal 11
The insertion hole 7a is also sealed by the same phenomenon.

Since the injected organic solvent is volatile, it evaporates in a short period of time, and the waterproofing process is completed in a short period of time. If necessary, washing with water or alcohol such as methanol or ethanol may be performed as a post-treatment.

Laminated busbar wiring board B waterproofed in this way
are placed in the main body case 2 and the lid case 4 is fitted, and the organic solvent is infiltrated into the mating surfaces 2a and 4b by means of injection, spraying, etc. in the same manner as described above, and welded. It is preferable that the main body case 2 is provided with a plurality of extraction holes 17 so that water or excess organic solvent that has entered the case due to some reason can be extracted.

Preferred combinations of organic solvents corresponding to the materials of the insulating substrate and each case are as follows.

ABS resin: Acetone, benzene, tetrahydrofuran Methyl methacrylate resin: Methyl ethyl ketone Vinylidene chloride resin: Dimethyl formamide, dioxane Diacetyl cellulose: Alcohol, acetone Polystyrene resin: Toluene, benzene, ketone Vinyl chloride resin: Cyclohexane As described above, the outer shell of JB The fitting part of the case that makes up the case can be easily and reliably fitted on JB's assembly line by infiltration of the organic solvent into the gap by capillary action and by melting and evaporating the resin that serves as the insulating substrate. There is no longer any risk that the waterproof function will deteriorate due to an increase in the number of parts or aging due to the use of conventional rubber gaskets.

3 and 4 show another embodiment of the invention. That is, FIG. 3 shows a laminated busbar wiring board in which a weir 18 having a tapered portion 18a is provided in the insertion hole _7a of the uppermost insulating substrate 72.
This can prevent the electrical contact portion of the tab-shaped terminal 11 with the mating terminal from being contaminated by organic solvents or the like. FIG. 4 shows a busbar circuit 6 in which grooves 19 are provided vertically and horizontally. This results in
The organic solvent can easily penetrate into the busbar circuit portion, and together with the vein-shaped grooves 13, the laminated busbar wiring board B can be sealed more quickly and reliably.

FIG. 5 shows another embodiment of the present invention, in which a solvent injection hole 20 is provided in a part of the lid cover 4, through which an organic solvent is injected into the interior.
In this case, waterproof sealing between each insulating substrate in the laminated busbar wiring board and waterproof sealing between the fitting surfaces 2a and 4b of the main body case 2 and lid case 4 should be performed simultaneously using the same phenomenon as described above. Can be done. Note that a part of the busbar circuit 6 is constructed across other circuits as indicated by the reference numeral 6'. It goes without saying that the injection hole 20 and the extraction hole 17 are sealed by inserting rubber plugs or the like after waterproofing.

The above describes an example in which an organic solvent is injected or sprayed when welding the fitting surface of each case or the insertion hole of a tab-shaped terminal.
It is also possible to pull it up and dry it.

Effects of the Invention As is clear from the above explanation, the present invention
The JB's waterproof structure uses an organic solvent to weld the fitting part of the synthetic resin case that makes up the outer shell of the JB, the insertion hole for the tab-shaped terminal in the insulating board, etc. There is no decrease in waterproof function due to In addition, between each insulating substrate in the laminated busbar wiring board housed inside, the organic solvent permeates the entire surface of the insulating substrate through the shallow grooves provided in the form of leaf veins, so the organic solvent can be waterproofed in the same manner as above. Sealing is performed reliably, production costs can be greatly reduced compared to conventional resin filling, and an increase in weight can also be prevented.

[Brief explanation of drawings]

FIG. 1 is an exploded perspective view of a junction box showing one embodiment of the present invention, FIG. 2 is an enlarged perspective view of the laminated busbar wiring board in FIG. 1, and FIGS. FIG. 5 is a partially cutaway perspective view of a junction box showing another embodiment of the present invention. , FIG. 6, and FIG. 7 are explanatory diagrams of conventional examples, respectively. A... Busbar wiring board, B... Laminated busbar wiring board, 1... Waterproof case, 2... Main body case, 4... Lid case, 6... Busbar circuit, 7... Insulating board, 20...
Injection hole, 1a, 2a, 4b, 4c...fitting surface.

Claims (1)

[Scope of Claims] 1. A plurality of busbars having a desired pattern and having upwardly or downwardly facing tab-shaped terminals connected in an upright manner at the ends or intermediate portions and an insulating substrate are stacked in multiple layers, and the tab-shaped A laminated bus bar wiring board with terminals protruding from insertion holes provided in an insulating substrate to the top or bottom layer is housed between a lid case and a main body case, and the tab-shaped terminal group is inserted into the lid case or the main body case. In the junction box, which is made to protrude into a connecting part for an external connector etc. provided on the board, and whose lid case is covered with a waterproof cover, one of the two opposing insulating boards sandwiching the busbar circuit among the laminated busbar wiring boards. The surface is provided with a busbar mounting groove for the busbar circuit, so that the two opposing insulating substrates are brought into close contact with each other during the stacking process, and the other surface is provided with a busbar mounting groove for the busbar circuit to prevent organic solvent from entering easily. A shallow groove is provided in the form of a leaf vein to allow the tab-shaped terminal to pass through, and the insertion hole of the insulating substrate is formed in a size that is substantially close to the outer periphery of the tab-shaped terminal when the tab-shaped terminal is inserted thereinto. and the insertion hole, between the vertically opposing insulating substrates constituting the laminated busbar wiring board, and between the fitting portion of the main body case and the lid case constituting the outer shell of the junction box. The waterproof structure of the junction box is characterized by being welded and sealed with an organic solvent.