JP2001309526A - Connecting structure for internal circuit of junction box to relay - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a relay connecting structure capable of reducing the number of layers of bus bars in a junction box. SOLUTION: Bus bars for base circuit provided in the junction box and bus bars for relay connection are separated from each other. One end of each of the bus bars for relay connection is welded to the terminal of a relay, and the other end thereof is welded to each of the bus bars of base circuit.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a connection structure between a relay and an internal circuit of a junction box connected to a wire harness for an automobile.

[0002]

2. Description of the Related Art In recent years, with the rapid increase of electrical components mounted on automobiles, the number of electric junction boxes for automobiles, especially the circuits accommodated in junction boxes, has rapidly increased, and branch circuits are formed at high density. In addition, the number of parts is very large, and the number of assembling steps is very large.

[0003] In a junction box 1 shown in FIG. 10 among the electric junction boxes 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. The upper case 2 is provided with a connector accommodating portion 2a, a relay accommodating portion 2b, and a fuse accommodating portion 2c, and a connector 6, a relay 7, and a fuse 8 are mounted on these accommodating portions, and are protruded from these terminals and the bus bar. The tab is connected directly or via a relay terminal. The lower case 3 is also provided with a connector accommodating portion 3a, and the tab 5a of the bus bar projects to connect 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 the case where it 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 vertically opposed positions, the tabs bent by the bus bar overlap and cannot be developed. Therefore, it is necessary to provide the tab on the bus bar of another layer. This causes the number of layers to increase. As described above, when the number of layers of the bus bar increases, there is a problem that the height of the junction box increases and the size of the junction box increases.

Further, if the specification of the connector connection part in the internal circuit of the junction box changes, for example,
Even if the specification of the relay connection circuit is not changed, the entire internal circuit must be changed, and the entire bus bar needs to be newly formed, which has a problem that the circuit change cannot be easily handled.

Furthermore, when connecting the bus bar and the relay, since both the tab of the bus bar and the terminal of the relay are male terminals, they are connected via female-female relay terminals, so that the number of parts increases and the assembly is increased. There is a problem that takes time.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems, and suppresses an increase in the number of bus bars accommodated in a junction box, thereby making it possible to reduce the thickness of the junction box. Another object of the present invention is to connect the internal circuit of the junction box to a relay without using a relay terminal.

[0009]

In order to solve the above problems, the present invention divides a bus bar of a base circuit portion provided in a junction box and a bus bar for relay connection, and connects one end of the bus bar for relay connection to a relay. A connection structure for connecting an internal circuit of a junction box and a relay, wherein the connection structure is welded to a terminal and the other end is welded to a bus bar of the base circuit portion.

As described above, since the base circuit bus bar and the relay connection circuit are divided in the junction box, the tab provided on the base circuit bus bar and the tab provided on the relay connection bus bar overlap. Therefore, multilayering of the bus bar is suppressed, and the junction box can be reduced in thickness. In addition, since the circuit layout of each bus bar is also simplified, the area of each bus bar can be reduced.As a result, even if the bus bar is divided, the overall bus bar area can be reduced, and the increase in the junction box area can be suppressed. it can.

Further, since the relay connection bus bar is provided separately, the specification of the connector connection circuit is changed and the specification of the relay connection circuit is not changed or vice versa. It is possible to easily cope with the specification change.

Further, since the terminals of the relay are directly welded to the relay connection bus bar, no relay terminal is required.
The number of parts can be reduced, and the space can be reduced accordingly.

Specifically, there is provided a relay module in which the relay connection bus bar is fixed on a substrate, a relay is accommodated in a relay accommodating portion provided on the substrate, and terminals of the relay are connected to the relay connection bus bar. It is welded to one end. The relay module is mounted on a junction box, and the relay accommodating portion is exposed on the outer surface of the junction box.

Alternatively, a relay module is provided in which the relay connection bus bar is fixed on a board, and the relay module is housed in a junction box without providing a relay housing portion on the board and provided in an upper case or a lower case of the junction box. A relay is housed in the housing, and the terminal of the relay is welded to one end of the relay connection bus bar housed in the junction box.

Alternatively, there is provided a relay module in which the relay connection bus bar is fixed on a board, the relay is directly mounted on the board of the relay module, and the terminals of the relay are projected from holes formed in the board. Thus, it is welded to one end of the relay connection bus bar. That is, the relay is placed on the board of the relay module without providing the relay accommodation section on the board of the relay module or the case of the junction box, and the terminals are welded to the bus bar by passing the terminals through the holes of the board. It is fixed.

The bus bar for relay connection is provided with a bus bar to be connected to each terminal of the relay.
Also, the relay connection bus bar is bent at both ends of the horizontal portion to form a welded portion. The welding portion of the relay connection bus bar and the welding portion of the bus bar of the base circuit are joined and connected by ultrasonic welding, resistance welding or laser welding.
It is preferable that the welded portion protrudes outward from the insulating plate and the substrate.

As described above, the bus bar for the base circuit and the bus bar for the relay connection are divided but are connected by welding, so that the electrical connection reliability does not decrease.
If these welds are arranged in parallel, the ultrasonic welding, resistance welding or laser welding can be performed efficiently. Further, the welded portions which are brought into contact with each other and welded may be overlapped and welded in a horizontal direction, or may be bent in a vertical direction and overlapped and welded in a vertical direction.

Although bus bars for base circuits and insulating plates are alternately stacked inside the upper case and the lower case, an electronic control unit may be accommodated. In this case, it is preferable to connect the welded portion between the bus bar for the base circuit and the bus bar for the relay connection by using the dead space below the electronic control unit. Further, if necessary, a circuit composed of an electric wire and a press contact terminal or / and a circuit body such as an FPC or a PBC may be accommodated.

[0019]

Embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a schematic exploded perspective view of components constituting a junction box 10 connected to a wire harness for an automobile, and FIGS. 2 to 5 show a state where each component is assembled.

In FIG. 1, 11 is a lower case, 12 is an upper case, 13 is a base circuit, 14 is a fuse module, and 15 is a relay module. Although not shown in FIG. 1 in the junction box 10,
The electronic control unit 40 is also accommodated as shown in FIGS.

The lower case 11 has a connector housing 1
1a are provided in a protruding manner, and a relay opening 11b is provided on one side in the long side direction. The upper case 12 has a fuse opening 12 on one side in the short side direction.
a is provided. The lower case 11 and the upper case 12 are engaged with each other so that the peripheral walls are fitted and locked. Although not shown in FIG. 1, the vehicle body fixing bracket 12 c protrudes from the peripheral wall of the upper case 12 as shown in FIGS. 2 to 6. Further, the upper case 12 has a notch 1 for fitting a connector in a part of its peripheral wall.
2b is provided.

The base circuit section 13 has a connector bus bar 16 stacked vertically with an insulating plate 17 interposed therebetween.
In the present embodiment, the connector bus bar 16 has four layers. The size of the base circuit portion 13 is set so as not to be disposed at the position of the relay opening 11b inside the case constituted by the lower case 11 and the upper case 12.

Each layer of the connector bus bar 16 of the base circuit portion 13 is formed by punching one conductive plate to form a circuit portion 16a having a required shape. A tab 16b protruding from the circuit portion 16a to the lower case 11 side is provided so as to protrude from the terminal hole 11c of the connector accommodating portion 11a provided in the lower case 11. A connector (not shown) connected to the distal end of the wire harness is fitted into the connector accommodating portion 11a to connect the terminal in the connector to the tab 16b.

The required circuit portion 16a of the connector bus bar 16 is provided with welding portions 16c and 16d projecting from the peripheral edge of the insulating plate 17. The welding portion 16 c is provided so as to protrude from the outer peripheral edge of one side of the insulating plate 17, and the welding portion 20 c of the fuse bus bar 20 of the fuse module 14 is formed.
a to be welded. That is, the welded portion 16c-1 is a welded portion 20a-1, 16c-2 is a welded portion 20a-2, and 16
c-3 and 20a-3 are horizontally overlapped and welded. Also, the welded portion 16 d is
And is welded to the welded portion 31a of the relay connection bus bar 31 of the relay module 15, and these welded portions 16d and 31a are L
It is bent into a shape and overlapped and welded in the vertical direction. The welds 16c-1, 16c-2, 16
c-3 has a large number of welds projecting in parallel.

In the relay module 15, a large number of relay connection bus bars 30 are fixed to a substrate 31, and these relay connection bus bars 30 are individually provided with those connected to the respective terminals of the relay, so that the bus bars are separated. I have. A large number of relay housings 31a
These relay housings 31a house the resin-molded main body 35b of the relay 35, and the relays 3a through the terminal holes formed on the bottom surface of the relay housing 31a.
The fifth terminal 35a is made to protrude. When the relay module 15 is accommodated in the upper case 12 and the lower case 11, the relay case 31 a
It is set so as to be located at one opening 11a and exposed to the outer surface.

As shown in FIG. 6, a large number of bus bars 30 of the relay module 15 have welding portions 30a and 30c projecting by bending both ends of a horizontal portion 30b fixed to the substrate 31. One of the welded portions 30c protrudes from the substrate 31 and protrudes from the terminal hole 31b.
5a is welded. The other welding portion 30a protrudes from the peripheral edge of the substrate 31, and is for welding the bus bar 16 of the base circuit.

The fuse module 14 includes a substrate 21
On the back surface (the top surface in FIG. 1), a large number of bus bars 20 for fuses are arranged and fixed. These busbars 20 are individually provided with those connected to the respective terminals of the fuses, and are, so to speak, composed of different busbars. As shown in FIG. 2, a large number of fuse accommodating portions 21a protrude from the front surface side. This fuse accommodating portion 21a is used for the fuse module 1
When the upper case 4 is accommodated in the upper case 12 and the lower case 11, the upper case 4 is located at the opening 12a of the upper case 12 and is exposed to the outside.

As shown in FIG. 7, a large number of bus bars 20 of the fuse module 14 are formed by projecting a terminal portion 20c at one end of a horizontal portion 20b fixed to the substrate 21 by bending the terminal portion 20c. A press contact groove 20d into which the terminal 25a is fitted is provided. The other end of the bus bar 20 is the above-mentioned welded portion 20a, which is bent in a stepped manner so as to overlap the welded portion 16c of the connector bus bar 16 vertically.

When assembling the junction box 10 from the above-described components, first, the fuse module 14 is disposed above one side of the base circuit portion 13, and the welding portion 20 a of the bus bar 20 is connected to the welding portion 16 c of the bus bar 16. Overlap and weld. Also, the relay module 15 is arranged on one side of the base circuit portion 13, and the welded portion 30 a of the bus bar 30 is joined to the welded portion 16 d of the bus bar 16 of the base circuit portion 13 and welded. This welding is performed by ultrasonic welding, resistance welding, or laser welding.

After the fuse module 14 is mounted on the upper side of the short side of the base circuit section 13 and the relay module 15 is arranged on the side of the long side, and integrated. Are accommodated in the lower case 11. At this time, the board 31 of the relay module 15 is exposed to the opening 11b of the lower case 11, and the relay housing 31a projects outside.

Next, the electronic control unit 40 is mounted above the base circuit section 13 where the fuse module 14 is not mounted. The electronic control unit 40 includes, on one side thereof, a connector portion 44 which is formed by bending a conductive pin 43 connected to a conductor 42 fixed to a substrate 41 and projecting the bent portion. The connector portion 44 is fitted into a connector fitting hole formed by the notch 12b of the peripheral wall of the lower case 11 and the upper case 12, and is exposed to the outside. Further, the conductor 42 of the electronic control unit 40 is connected to a tab 16 f projecting from the bus bar 16 of the base circuit unit 13. A large number of electronic components 45 are mounted on a board 41 of the electronic control unit 40 and connected to the conductor 42. These electronic components 45
Are fixed to the substrate 41 so as to protrude downward.

After assembling the electronic control unit 40 as described above, the upper case 12 is assembled. At this time, the board 20 of the fuse module 14 is exposed through the opening 12a of the upper case 12, and the fuse accommodating portion 21a and the fusible link accommodating portion 21b provided on the substrate 20 project outside. The upper case 12 and the lower case 1
By associating with the lock box 1, the assembly of the junction box 10 is completed.

It is to be noted that the dead space below the electronic control unit 40 may be used to determine the welding connection position between the bus bar and the bus bar for relay connection.

FIG. 8 shows a second embodiment of the relay module 15. The relay module is not provided with a relay housing, but a relay housing 50 is provided in the upper case 12, and the relay 35 is housed in the relay housing 50. And the relay 35
Terminal 35a protrudes from the inner surface of the upper case 12. The board 31 of the relay module 15 has a substantially flat plate shape, and the bus bar 30 for relay connection is fixed to the board 31.
Welds 30a and 30c are bent at both ends. The relay 3 protruding from the upper case 12 at the welding portion 30c
5 terminal 35a is welded.

FIG. 9 shows a third embodiment of the relay module 15, in which the relay module is not provided and the relay module 1 is not provided.
The relay 35 is directly mounted on the substrate 31 of FIG. 4, the terminal 35 a is projected from a hole 35 c provided on the substrate 31, and the welding portion 3 of the relay connection bus bar 30 fixed to the back surface side of the substrate 31.
0c.

[0036]

As is clear from the above description, according to the junction box of the present invention, the bus bar for the base circuit and the bus bar for the relay connection are divided, so that the connection between the connector and the relay is achieved. The tabs do not overlap and do not overlap, and as a result, it is not necessary to increase the number of stacked bus bars to provide the tabs.
As a result, the thickness of the junction box can be reduced. In addition, the relay connection bus bar is welded to the relay terminals, eliminating the need for conventional relay terminals, reducing the number of components, reducing the number of assembly steps, and reducing the required space. it can.

Further, since the relay connection tab is separated from the bus bar of the base circuit section as described above, the circuit layout of the bus bar of the base circuit section becomes simple and the required area can be reduced. it can. As a result, even if the bus bars are divided and the ends of the bus bars are connected by welding, the occupied area does not increase as a whole, and the area of the junction box does not increase.

Further, if the specification of the connector connection circuit or the relay connection circuit is changed, the bus bar of the base circuit portion or the bus bar of the relay module may be changed.
Since it is not necessary to change the entire bus bar, the upper case, and the lower case, it is possible to respond to the specification change quickly and inexpensively.

[Brief description of the drawings]

FIG. 1 is a schematic exploded perspective view of a junction box according to a first embodiment of the present invention.

FIG. 2 is a plan view showing a state where the junction box is assembled.

FIG. 3 is a bottom view of FIG. 2;

FIG. 4 is a sectional view taken along line IV-IV of FIG. 2;

FIG. 5 is a sectional view taken along line VV of FIG. 2;

FIGS. 6A and 6B are schematic diagrams showing a relay connection bus bar.

FIG. 7 is a schematic diagram showing a fuse bus bar.

FIG. 8 is a schematic view showing a second embodiment.

FIG. 9 is a schematic view showing a third embodiment.

FIG. 10 is an exploded perspective view showing a conventional junction box.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Junction box 11 Lower case 11a Connector accommodating part 11b Opening 12 Upper case 12a Opening 13 Base circuit part 14 Fuse module 15 Relay module 16 Connector connection bus bar 16c, 16d Welding part 17 Insulating plate 20 Fuse bus bar 20a Welding part 21 Substrate 21a Fuse Housing 25 Fuse 30 Relay connection bus bar 30a, 30c Weld 31 Board 31a Relay housing 35 Relay 35a Terminal 40 Electronic control unit

Claims (6)

[Claims] 1. A bus bar of a base circuit portion provided in a junction box and a bus bar for relay connection are divided, and one end of the bus bar for relay connection is welded to a terminal of the relay, and the other end is connected to a terminal of the base circuit portion. Connection structure between the internal circuit of the junction box and the relay, which is welded to the bus bar. 2. A relay module in which the relay connection bus bar is fixed on a board, a relay is housed in a relay housing portion provided on the board, and a terminal of the relay is welded to one end of the relay connection bus bar. Claim 1 which is connected
Connection structure between the internal circuit of the junction box and the relay described in. 3. A relay module in which the relay connection bus bar is fixed on a substrate, a relay is accommodated in a relay accommodating portion provided in an upper case or a lower case of the junction box, and terminals of the relay are connected to the junction box. 2. The connection structure between an internal circuit of a junction box and a relay according to claim 1, wherein one end of the relay connection bus bar accommodated in the relay box is welded. 4. A relay module in which the relay connection bus bar is fixed on a board, a relay is mounted on a board surface of the relay module, and terminals of the relay are protruded from holes formed in the board. 2. The connection structure between an internal circuit of a junction box and a relay according to claim 1, wherein the connection is welded to one end of the relay connection bus bar. 5. The internal circuit of a junction box according to claim 1, wherein the bus bar for relay connection is provided with a bus bar individually connected to each terminal of the relay. Connection structure. 6. The relay connection bus bar according to claim 1, wherein both ends of the horizontal portion are bent to form a welded portion.
The connection structure between the internal circuit of the junction box and the relay according to any one of the above.