JP3501081B2 - Junction box - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a shunt box connected to a wire harness for an automobile, and particularly to easily connecting internal circuit bodies to each other without using a relay part.

[0002]

2. Description of the Related Art Recently, with the rapid increase in electrical components mounted on automobiles, the number of circuits contained in automobile electrical junction boxes, especially junction boxes, has increased rapidly to form branch circuits with high density. In addition, the number of parts is extremely large, and the number of assembly steps is also large.

In the junction box 1 shown in FIG. 6 among the electric connection boxes for automobiles, bus bars 5A to 5D are laminated between upper case 2 and lower case 3 with insulating plates 4A to 4E interposed. Further, insulating plates 4F and 4G having electric wire guide grooves are provided at both upper and lower ends, and single-core wires 6A and 6B are wired and accommodated on the insulating plates 4F and 4G to be installed in the upper case 2 and the lower case 3. The connector accommodating portion, the relay accommodating portion, the relay fitting in the fuse accommodating portion, the fuse, and the connector terminal are connected to the tab protruding from the bus bar, and the single core wires 6A, 6
B is pressure-connected to a pressure contact terminal (not shown), and the pressure contact terminal is connected to terminals of a connector, a relay, and a fuse. Although not used in the electric junction box, an F having a structure in which a conductor is sandwiched between resin films is used as an internal circuit.
PC (Flexible Printed Circuit), PCB
(Print boat circuit) may also be used in combination.

When it is necessary to connect a large current circuit composed of the bus bar, a medium current circuit composed of a single core wire, and a small current circuit composed of FPC, etc., a medium current circuit is connected to the large current circuit as shown in FIG. And a small current circuit is connected to the medium current circuit. As shown in FIG. 8, the bus bar 5 of the large current circuit and the single core wire 6 of the medium current circuit are connected to each other by pressing the tabs 5a provided on the bus bar 5 and the pressure contact terminals 7 connected to the single core wire 6 by pressure. The tab 7a of the above is connected via the relay terminal 8. Also, when connecting the single core wire 6 and the FPC and the bus bar 5 and the FPC, the connection is made with the relay terminal interposed.

[0005]

As described above, since the internal circuit bodies in the junction box are connected to each other in the order of large current circuit → medium current circuit → small current circuit, there are many connection points. There are also many connecting parts. Further, as shown in FIG. 8, these connection points are
Since the operation is performed via the relay terminal, the structure inside the junction box becomes very complicated, and the number of parts and the number of assembling steps are increased. Further, since the installation space for the relay terminal is required, there is a problem that the junction box becomes large and its weight increases.

The present invention has been made in view of the above problems, and an object thereof is to connect internal circuit bodies to each other without using a relay terminal.

[0007]

In order to solve the above problems, the present invention provides an internal circuit body housed in an upper case and a lower case of a junction box.
A bus bar forming a large current circuit, a single core wire forming a medium current circuit, and a circuit body including a circuit made of an FPC, PCB or / and a highly conductive resin forming a small current circuit are laminated and arranged, Of the circuit bodies, those that need to be connected to each other are such that the tip ends are extended and are welded and connected at the extending portions, and the extending portions are provided between the peripheral walls facing each other of the upper case and the lower case. We provide a junction box characterized by being sandwiched.

It is preferable to use an FPC as a small current circuit that is welded to the other internal circuit body.

As described above, the bus bar, the single core wire, and the FPC to be connected have their ends extended, and the extended portions are welded to be electrically connected without using a relay terminal. be able to. The extended portion is
Since the insulating plate is provided so as to project from the outer periphery of the insulating plate interposed between these internal circuit bodies, it is possible to perform welding by resistance welding or ultrasonic welding, and workability can be improved.

Specifically, the bus bar and the single core wire, the single core wire and the FPC are respectively welded, or three different internal circuit bodies of the bus bar, the single core wire and the FPC are welded at the same time. When welding at the same time, in the extension of the bus bar,
The core wire exposed from the end of the single core wire and the conductor exposed from the end of the FPC are overlapped and integrally welded.

The extending portion of the bus bar is formed by bending it in advance, and the single core wire and the end of the FPC are bent along the extending portion of the bus bar, and these bending portions are divided into upper case and lower case. It is sandwiched between the peripheral walls facing each other.

If the welded portion is bent as described above,
If the area of the junction box is not increased and the weld is sandwiched between the peripheral walls of the upper case and the lower case, it is not necessary to separately provide a means for holding the weld.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described with reference to the drawings. 1 and 2 show a junction box 10 according to the first embodiment of the present invention. The junction box 10 is connected to a wire harness for an automobile and houses an internal circuit body inside a box formed by an upper case 11 and a lower case 12. The internal circuit body includes a medium current circuit formed by stacking electric wires (single core wire) 13 arranged on an insulating plate (not shown) provided with electric wire guide grooves from the lower case 12 side, and an upper portion thereof. To FPC1
5 is formed by stacking and arranging a small current circuit and a PCB (print board circuit 25 is arranged, and further, a large current circuit is formed by stacking and arranging a bus bar 17 on the upper side of which an insulating plate 16 is interposed. The layer of the electric wire 13 is surrounded by a partition wall 19a, the layer of the FPC 15 is surrounded by a partition wall 19b, and the layer of the bus bar 17 is surrounded by a partition wall 19c.

The large current circuit consisting of the bus bar, the medium current circuit consisting of a single core wire, and the small current circuit consisting of FPC and PCB are connected as shown in FIG. FP
As shown in FIG. 4, a circuit body 52 integrally formed with C and PCB with the circuit portion 50 made of a highly conductive resin embedded in a substrate portion 51 made of an insulating resin may be laminated for a small current circuit. .

On the upper surface of the upper case 11, the connector accommodating portion 30 and the fuse accommodating portion 3 are formed over substantially the entire surface.
1. A relay accommodating portion (not shown) is formed by projecting, and terminals of connectors, fuses, and relays respectively fitted in these accommodating portions are connected to tabs projecting from the bus bar 17. . Further, the lower case 12 is also provided with the connector accommodating portion 30, and the tab of the pressure contact terminal 18 press-contacted to the electric wire 13 is projected into the terminal accommodating chamber of the connector accommodating portion 30 to be connected to the wire harness (not shown). It is connected to the connector. Also, FPC15 and PCB
25 is also a connector housing portion (not shown) provided in the lower case
It is connected to an external circuit via a connector fitted to.

The uppermost bus bar 17A of the bus bars 17 is internally connected to the single core wire 13A and the FPC 15A. Specifically, the bus bar 17A has a partition wall 19c whose tip portion is arranged outside the outer periphery of the insulating plate 16 in advance.
The extending portion 20 is formed so as to protrude from the opening 19d of the above, and the extending portion 20 is bent upward. The single core wire 13A and the FPC 15A are divided into partition walls 19a and 1a, respectively.
9b while protruding from the opening 19d of the single core 1
The core wire 13a exposed from the terminal of 3A and the FPC 15A
After extending the tip of the conductor 15a exposed at the end of the conductor 15a and bending it so as to overlap the extending part 20, the bent parts 21 are simultaneously resistance welded 23 to be connected to each other. . This bus bar 17A, single core wire 13a,
The welding of the conductor 15a of the FPC is performed before the lower case 12 and the upper case 11 are assembled. Alternatively, they are welded after being assembled to the lower case 12. Note that the connection method is not limited to this, and the single core wire and the FPC may be welded and bent along the bus bar, and then the FPC and the bus bar may be welded.

As shown in FIG. 2, the bent portion 21 is sandwiched and housed between the peripheral walls of the upper case 11 and the lower case 12. Specifically, on the inner side of one side wall 11a of the peripheral wall of the upper case 11 facing the bent portion 21,
An inner side wall 11b is provided apart from the side wall 11a.
1a is fitted on the outer peripheral side of the side wall 12a of the lower case 12 extending to the upper surface of the junction box 10, while the inner side wall 11b is located inside the side wall 12a of the lower case 12 and is connected to the side wall 12a. A gap 22 is formed between the upper and lower ends of the bus bar 17, and the bent portion 21 is accommodated from below in the gap 22 so that the inner side wall 11b and the lower case side wall 12 are formed.
It is configured to be sandwiched with a.

By extending the ends of the bus bar, the single core wire and the FPC which are connected to each other in the same direction and overlapping and welding them in this manner, electrical connection can be made without using a relay terminal, and the structure becomes complicated and the junction is formed. The size and weight of the box can be prevented.

Further, by bending the welded portion along the side walls of the upper case and the lower case, it is possible to avoid increasing the size of the junction box. Further, an inner side wall 11b is provided inside the upper case, and the bent portion 2 is formed by the inner side wall 11b and the peripheral wall 12a of the lower case.
Since 1 is sandwiched, it is possible to efficiently hold and store the bent portion made of a conductor, and it is possible to prevent external interference with the bent portion.

FIG. 5 shows a junction box 10 'according to the second embodiment of the present invention. In the present embodiment, the upper case 11 'is fitted inside the lower case 12', and the inner side wall 12b 'is provided inside the side wall 12a' of the lower case 12 'so that the extending portion 20' is bent downward. The bent portion 21 'is housed in the gap 22' between the inner wall 12b 'and the side wall 11a' of the upper case 11 '. Also in this case, since the bent portion 21 ′, which is the welded portion, can be sandwiched between the peripheral walls of the upper case and the lower case, the welded portion can be held without taking space while preventing interference from the outside.

The present invention is not limited to the above embodiment, but can be applied to the case of connecting only the bus bar and the FPC and the case of connecting only the bus bar and the single core wire. Also,
Instead of providing the inner side wall, a gap may be provided between the side walls of the upper case and the lower case, and the bent portion may be housed in the gap so as to be directly sandwiched between the side walls. Further, the PCB constituting the small current circuit and the circuit body shown in FIG. 4 are also provided with the extending portions, and directly connected by welding to the large current circuit body made of the bus bar and / or the medium current circuit body made of the single core wire. Good.

[0022]

As is apparent from the above description, according to the junction box of the present invention, the bus bar of the large current circuit, the single core wire of the medium current circuit, which constitutes the internal circuit body,
Of the FPCs for small current circuits, those that need to be connected to each other are extended and welded at the extended portions, so connections between these circuits can be made simple and a relay that requires an installation space is required. No terminals are required, and it is possible to prevent the assembly and structure from becoming complicated and the junction box from becoming large.

Further, by bending the welded portion along the side walls of the upper case and the lower case, the bent portions are accommodated in the gap between the side walls of the upper case and the lower case without newly providing a holding means. Can be sandwiched between. Further, by providing an inner side wall inside the side wall of the upper case and the lower case that fits to the outer peripheral side, and sandwiching the bent part between the inner side wall and the side wall of the other case, a bent part made of a conductor is formed. It is possible to reliably prevent external interference.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a junction box according to a first embodiment of the present invention as seen from a side surface.

FIG. 2 is an enlarged cross-sectional view of a main part of the junction box shown in FIG.

FIG. 3 is an internal circuit diagram of FIG.

4A and 4B are perspective views of a circuit body used for a small current circuit.

FIG. 5 is an enlarged sectional view of an essential part of the junction box according to the second embodiment of the present invention.

FIG. 6 is an exploded perspective view showing a conventional example.

FIG. 7 is a conventional internal circuit diagram.

FIG. 8 is a view showing a conventional connection form.

[Explanation of symbols]

10, 10 'junction box 11, 11 'upper case 12,22 'lower case 13 single wire 16 Insulation plate 15 FPC 17 bus bar 18 Pressure contact terminal 20, 20 'extension 21, 21 'bend

─────────────────────────────────────────────────── ─── Continuation of the front page (72) Nobufumi Kobayashi 1-14 Nishisuehiro-cho, Yokkaichi-shi, Mie Sumitomo Wiring Systems, Ltd. (56) Reference JP-A-8-265936 (JP, A) JP 2000 -50463 (JP, A) JP-A-11-312568 (JP, A) JP-A-6-36833 (JP, A) JP-A-11-191914 (JP, A) (58) Fields investigated (Int.Cl) . ⁷ , DB name) H02G 3/16 B60R 16/02 H01R 4/02

Claims (5)

(57) [Claims] 1. An internal circuit body housed in an upper case and a lower case of a junction box,
A bus bar that constitutes a large current circuit, a single core wire that constitutes a medium current circuit, and a circuit body including a circuit made of FPC, PCB or / and a highly conductive resin that constitutes a small current circuit are laminated and arranged, of the circuit element, it is that there is a need to connect with each other, by extending the tip, along with being welded connection the extending portion, and the upper case of the extending portion Roake
A junction box characterized by being sandwiched between the peripheral walls facing each other . 2. The bent portion is preliminarily bent to form the bent portion.
Between the facing peripheral walls of the upper case and the lower case.
The junction box according to claim 1, which is sandwiched . 3. A small electric wire welded to the other internal circuit body.
The junction box according to claim 1, wherein an FPC is used as the flow circuit . 4. The single core wire is provided on the extending portion of the bus bar.
Core wire exposed from the terminal, exposed from the FPC terminal
The junction box according to claim 3 , wherein the conductors are overlapped and integrally welded . 5. The extension portion of the bus bar is bent in advance.
The single-core wire and the FPC terminal are
The bending is performed along the bent extending portion of the groove.
To the junction board according to claim 4.
X.