JP3698033B2 - Junction box - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to di-catcher down action box, particularly, in a junction box to modularize relates to implementing the electrical components such as relays to the bus bar by soldering.
[0002]
[Prior art]
Recently, with the rapid increase in electrical components mounted on automobiles, the number of parts accommodated in electrical junction boxes for automobiles, especially the number of circuits accommodated inside junction boxes, has increased to form a branch circuit with high density. It has become very large, and it takes a lot of assembly work.
[0003]
Among the electrical junction boxes for automobiles, in the junction box 1 shown in FIG. 7, the bus bars 5 </ b> A to 5 </ b> D are stacked with the insulating plates 4 </ b> A to 4 </ b> E interposed between the upper case 2 and the lower case 3. The upper case 2 is provided with a connector housing portion 2a, a relay housing portion 2b, and a fuse housing portion 2c, and a connector 6, a relay 7 and a fuse 8 are mounted on these housing portions and projecting from these terminals and the bus bar. It is connected to the terminal directly or via a relay terminal. The lower case 3 is also provided with a connector housing portion 3a, and the bus bar terminal 5a protrudes and is connected to the connector.
[0004]
[Problems to be solved by the invention]
In the junction box 1, the area of the bus bar and the number of stacked layers increase as the number of circuits increases, and there is a problem that the junction box increases in size. In addition, when the connector case, the relay case, and the fuse case are provided in both the upper case and the lower case, and the connector, relay, fuse and internal circuit are connected to the upper and lower surfaces of the junction box, the upper case or Compared with the case where it is provided only on one side of the lower case, an increase in the area of the junction box can be suppressed.
[0005]
However, if the connector accommodating portion and the relay accommodating portion or the fuse accommodating portion are provided at the upper and lower facing positions, the terminals refracted from the bus bar cannot be overlapped and deployed, so it is necessary to provide a terminal on the bus bar of the other layer, and the number of bus bars is Causes to increase. Thus, when the number of stacked bus bars increases, the height of the junction box increases and the junction box increases in size.
[0006]
In addition, since the connector, fuse and relay are connected to the bus bar in the junction box, the entire internal circuit must be changed when the specification changes that change the connection between the fuse, relay and internal circuit. Therefore, it cannot easily cope with circuit changes.
[0007]
In view of the above situation, if the bus bars connected to the connectors, relays, and fuses are arranged separately from each other, it is possible to cope with an increase in the number of bus bar layers due to overlapping of terminals provided on the bus bars. In addition, if the connector connection circuit part, the relay connection circuit part, and the fuse connection circuit part are also modularized, they can often be shared by different vehicle types and grades. Furthermore, in the relay connection circuit section with little circuit change, the direct connection between the bus bar and the relay terminal eliminates the need for a relay terminal and eliminates the need to provide a terminal or tab on the bus bar. Can be shared.
[0008]
Regarding the connection between the bus bar and the relay, a circuit portion dedicated to the relay is generated by modularization. Therefore, by mounting the relay on the bus bar, the merit of modularization can be utilized. As a mounting method, soldering is generally considered.
[0009]
For example, as shown in FIG. 8, the terminal case 7b of the relay case 7a is inserted into the terminal hole 9c of the circuit board 9 in which the bus bar 9a is molded with an insulating resin 9b, and the main body case shown in FIG. A method is conceivable in which the terminal 7b is connected to the bus bar 9a with the solder H in a state where the square leg 7c on the bottom surface of 7a is placed on the circuit board 9 and a gap S is formed between the leg 7c.
[0010]
Here, the gap S is provided as described above in order to release the gas generated from the solder melted during soldering. Otherwise, pores such as pinholes are generated inside the solder, and the mounting strength is insufficient. This is because it becomes a factor such as poor conduction. In addition to the above, the gap S may be formed by providing a spacer portion 7d ′ at the protruding base of the terminal 7b ′ of the relay 7 ′ as shown in FIG.
[0011]
However, in the method shown in FIG. 8, since the leg portion 7c itself is small, the contact area in contact with the upper surface of the circuit board 9 is limited only to the lower surface of the leg portion 7c. Therefore, the main body case 7a including a contact opening / closing mechanism such as a relay has a large mass. Therefore, vibrations associated with traveling of the automobile are also transmitted to the relay 7, and the main body case 7a is large with the soldered portion as the vibration center. There is a problem that such vibration cannot be prevented by contact with only the leg portion 7c.
[0012]
The above-mentioned vibration is generated in the same manner in the method shown in FIG. 10, and the bottom case square of the main body case 7a ′ is not in contact with the circuit board 9, so that the main body case 7a ′ is swung by the vibration. There is a problem that a load is applied to the soldering portion of the bus bar and the terminal. In particular, the modularized circuit board has a small board area, so vibration is easily amplified, which causes various stresses such as bending on the soldered part, which may cause peeling of the solder, and the reliability of conduction deteriorates. There is a problem to do.
[0013]
The present invention has been made in view of the above-described problems. The circuit in the junction box is accommodated in the junction box by modularizing the connector connection circuit portion, the relay connection circuit portion, and the fuse connection circuit portion. It is an object of the present invention to suppress the increase in the number of stacked bus bars, reduce the thickness of the junction box, and easily cope with circuit changes. It is another object of the present invention to solve the above-mentioned problem that occurs when the modular bus bar and an electrical component such as a relay are connected by soldering.
[0014]
[Means for Solving the Problems]
In order to solve the above problems, the present invention provides a relay module in which only a bus bar for a relay connection circuit connected to a relay on a circuit board is arranged inside a case consisting of an upper case and a lower case of a junction box mounted on an automobile. Which contains
The bus bar of the relay module is arranged with resin molding on the circuit board, and has a terminal hole for inserting a terminal of a relay to be mounted on the circuit board, and communicates with the terminal hole and mounted on the relay. The vent hole is formed on the non-opposite side of the terminal holes, and the terminal hole side is the deepest. A junction box is provided in which the depth is gradually reduced toward the extending side, and the terminal of the relay is inserted into the terminal hole to release the gas generated during soldering from the depression .
[0015]
As described above, when the gas vent is formed on the mounting surface of the circuit board, the gas can be released without providing a gap between the electric component and the circuit board as in the conventional case. That is, the electrical parts are not provided with leg portions or spacer portions on the main body case, and when the terminals are inserted into the terminal holes, the lower surface of the main body case comes into contact with the mounting surface of the circuit board. The recess is open outward from the outline of the electrical component. Therefore, even if the terminal hole is closed with an electrical component as described above, the terminal hole communicates with the outside through the gas vent, so that the gas can be surely extracted.
[0016]
In addition, as described above, the mounted relay itself is in contact with the circuit board on the entire lower surface of the main body case, so that the contact area is greatly increased and stability is increased compared to the conventional case, and the main body against vibrations and the like is also increased. The case can no longer be shaken, and accordingly, the soldered portion is not stressed and vibration resistance can be improved. Moreover, since it is not necessary to provide a leg part and a spacer part also for the relay used as attachment object, the cost concerning manufacture etc. can be reduced.
[0017]
Further, the gas vents provided to communicate with the terminal holes are formed on the non-opposing sides of the terminal holes and gradually become shallower from the terminal holes toward the mounting surface.
In this way, when the gas vent is formed, the gas can be released at the shortest distance from the terminal hole of the circuit board. Further, if the depth of the recess is also formed as described above, the gas flows smoothly, The gas emission efficiency can be increased.
[0018]
It is necessary to provide at least one vent hole for each terminal hole. However, in order to improve gas escape, a plurality of vent holes should be provided for one terminal hole. Alternatively, a plurality of degassing recesses provided in a single relay may be communicated with each other to improve degassing performance.
[0019]
The connector together with the upper cut rates also can be applied to the present invention when implemented in soldering connectors connected to word ear harness terminal occurs stress such as bending to the affected easily soldered portion of the vibration Although there is a tendency, by applying the above structure, it is possible to prevent adverse effects due to vibration and maintain connection reliability.
[0021]
In the present invention, the circuit in the junction box is modularized as a connector connection circuit portion, a relay connection circuit portion, and a fuse connection circuit portion, thereby suppressing an increase in the number of stacked bus bars accommodated in the junction box. The box can be made thin, and it can easily cope with circuit changes. Furthermore, such a modularized circuit unit has the above-described electrical component mounting structure, so that the circuit area is small. Therefore, even in a circuit board where vibration is likely to be amplified, vibration resistance is ensured and circuit reliability is ensured. Can also be maintained.
[0022]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 shows an exploded state of a modularized junction box 10 having a mounting structure according to an embodiment of the present invention. The junction box 10 divides the internal circuit accommodated in the upper case 10a and the lower case 10b as a connector connection circuit part, a fuse connection circuit part, and a relay connection circuit part, and the module as a connector module 11, a fuse module 25, and a relay module 12 We are trying to make it.
[0023]
In each of the above modules, the end of the bus bar integrated with the insulating plate or the like is protruded from the end of the insulating plate or the like as a welded portion, and the connector module 11 uses the welded portion 11a for the fuse protruding from the surrounding as the fuse. A required circuit is formed by joining the modules 25 to each other by overlapping and welding with the welded portion 25a of the module 25.
Similarly, the welded portion 11b for the relay projecting in an L shape of the connector module 11 is overlapped and welded with the welded portion 14a of the relay module 12.
[0024]
Therefore, by modularizing in this way, each module itself can be handled as a component, and mounting in which an electrical component is directly attached to a circuit is also possible. For example, in the relay module 12, the relay 20 is mounted and soldered to the bus bar 14 of the circuit board 13 molded with the insulating resin 15.
[0025]
FIGS. 2A and 2B show a circuit board 13 for the relay module 12, which is formed by coating an insulating resin 15 around the conductive bus bar 14 and forming terminal holes 16 for relay connection. Are provided in accordance with the terminal position of the relay 20.
Degassing recesses 17 are provided so as to communicate with the terminal holes 16 from the side portions of the terminal holes 16 that are not opposed to each other.
[0026]
That is, the degassing recess 17 is formed on the surface of the resin 15 serving as a mounting surface of the relay 20 in a direction orthogonal to the outside from the outer side 16a of the terminal hole 16, and when the relay 20 is attached, The length is set such that the opening extends outward from the outer shape line (indicated by a two-dot chain line in the figure, the same applies hereinafter) of the 20 main body cases 21. Further, the communication side with the terminal hole 16 is deepest so that the depth gradually decreases toward the extending side that is the mounting surface, and the width of the recess is substantially equal to the outer side 16 a of the terminal hole 16. Equivalent dimensions are set to ensure a sufficient opening area.
[0027]
The terminal hole 16 is soldered so that the resin hole 16b has a large opening, and the bus bar hole 16c has a small opening in accordance with the terminal 22 of the relay to be attached. The circuit board 13 is for welding connection with the modularized main connector module 11, and an L-shaped welded portion 14a continuous with the bus bar 14 is protruded from one side.
[0028]
On the other hand, the relay 20 to be attached is configured such that the connection terminal 22 protrudes from the lower surface of the box-shaped main body case 21, but there are no leg portions or spacer portions for gap formation as in the prior art. .
[0029]
As shown in FIGS. 3A and 3B, the relay 20 is mounted on the circuit board 13 by inserting the terminal 22 of the relay 20 into the terminal hole 16 of the circuit board 13 and connecting the lower surface 21a of the main body case 21 to the circuit. The substrate 13 is in contact with the upper surface 13a. Next, the terminal 22 and the bus bar 13 are soldered. At this time, the gas G generated from the molten solder H passes through the gas vent recess 17 from the terminal hole 16 and goes outward as shown in FIG. Has been released. At this time, since the bottom surface 17a of the degassing recess 17 gradually rises, the generated gas G is also released smoothly along the bottom surface 17a.
[0030]
Further, in the above connection state, the relay 20 is fixed so that the lower surface 21a of the main body 21 is in contact with the upper surface 13a of the circuit board 13 with a wide contact area, and the main body with mass is shaken even if vibration occurs. It is in a stable state.
[0031]
Note that the gas vent 17 is not limited to the above form, and is located in the middle with respect to the circuit board 13 ′ having terminal holes 16-1 ′ to 4 ′ as shown in FIG. 5, for example. Since the terminal holes 16-2 'have short upper and lower sides 16-2a', 2b 'on the outside, the width of the gas vents that can be formed is also limited. Therefore, in order to ensure a sufficient opening area, gas vents 17-2a ′ and 2b ′ are provided on the upper and lower sides so that the gas can be reliably discharged outward.
[0032]
Further, when the vent hole cannot be communicated from the outer side of the terminal hole due to surrounding conditions or the like, as shown in FIG. 6, it communicates from the inner side 16d ″ of the terminal hole 16 ″ of the circuit board 13 ″. The degassing recess 17 ″ may be formed so as to extend while curving outward. In the above embodiment, the relay module in the modular junction box has been described. However, in addition to the relay module, the mounting structure can be applied to the mounting of the connector portion or the like in a connector module or the like. The invention can also be applied to a board of a type in which electronic parts are soldered in a junction box that is not modularized.
[0033]
【The invention's effect】
As is clear from the above description, in the junction box of the present invention, the relay is stably mounted and fixed on the circuit board with a wide contact area while ensuring the release of the gas generated from the molten solder. Even if severe vibration or the like occurs during the running of the circuit, the reliability of the circuit can be ensured regardless of the stress or the like in the soldered portion. In addition, since it is not necessary to form a degassing leg or the like in the relay to be attached, the shape can be simplified and the cost of a mold or the like required for production can be reduced. Further, by modularizing the internal circuit, it is possible to prevent the junction box from becoming large and flexibly deal with circuit changes.
[Brief description of the drawings]
FIG. 1 is an exploded perspective view of a modular junction box to which a mounting structure of the present invention is applied.
FIG. 2A is a perspective view of a circuit board, and FIG. 2B is a cross-sectional view taken along the line AA in FIG.
FIGS. 3A and 3B are perspective views showing a state in which a relay is mounted on a circuit board. FIGS.
4 is a cross-sectional view taken along the line BB in FIG. 3 (B).
FIG. 5 is a plan view of a modified circuit board.
FIG. 6 is a plan view of another modified circuit board.
FIG. 7 is an exploded perspective view of a conventional junction box.
FIG. 8 is a cross-sectional view showing a mounting structure of a relay on a circuit board.
FIG. 9 is a bottom view of the relay.
FIG. 10 is a cross-sectional view showing a structure for mounting another relay on a circuit board.
[Explanation of symbols]
10 Junction box 12 Relay module 13 Circuit board 14 Bus bar 15 Resin 16 Terminal hole 17 Degassing recess 20 Relay 22 Terminal H Solder G Gas

Claims (2)

Inside the case consisting of an upper case and a lower case of a junction box mounted on an automobile, a relay module in which only bus bars for a relay connection circuit connected to a relay are arranged on a circuit board is housed,
The bus bar of the relay module is arranged with resin molding on the circuit board, and has a terminal hole for inserting a terminal of a relay to be mounted on the circuit board, and communicates with the terminal hole and mounted on the relay. The vent hole is formed on the non-opposite side of the terminal holes, and the terminal hole side is the deepest. A junction box configured such that the depth is gradually reduced toward the extending side, and a terminal of the relay is inserted into the terminal hole to release a gas generated during soldering from the depression . The case contains a connector module in which bus bars for connector connection to be connected to connectors are arranged on other circuit boards. The bus bar of the connector module and the end of the bus bar connected to the relay are accommodated. The junction box according to claim 1, wherein welded portions are provided, and the welded portions are overlapped and welded.

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