JP4725341B2 - Junction box for vehicles - Google Patents

Description

  The present invention relates to a junction box for a vehicle, and more specifically, to reduce the size of the junction box by using the internal circuit material of the junction box as a simple configuration.

  2. Description of the Related Art Conventionally, in a junction box mounted on a vehicle, as an internal circuit material, a conductive metal plate is a bus bar punched into a circuit pattern, and a plurality of layers of bus bars are often stacked with an insulating plate interposed. When an internal circuit is formed by a bus bar, it is often necessary to arrange the layers according to the rapid increase of electrical components in the vehicle and the position of the tabs provided on the bus bar. Therefore, in the recent junction box, the bus bar layer reaches 10 layers. There may be. As a result, there is a problem that the junction box is increased in size and weight.

  In some cases, a printed circuit board is used together with a bus bar as an internal circuit material of the electrical junction box. For example, Japanese Patent Laying-Open No. 2005-26052 (Patent Document 1) discloses a configuration in which a plurality of printed circuit boards are stacked and accommodated, and the conductors of these printed circuit boards are connected by press-fit terminals as shown in FIG. Has been. Specifically, the printed circuit boards 2 and 3 are arranged on the support piece 1 a provided on the inner peripheral wall of the lower case 1, and the press-fit terminals 4 formed with the press-fit portions 4 a at intervals are electrically conductive by plating of the printed circuit boards 2 and 3. The terminal holes 2a and 3a provided with films are press-fitted to connect the conductors of the upper and lower printed circuit boards 2 and 3.

  However, in order to perform the connection using the press-fit terminal 4, since the electrical connection is performed only by press-fitting, the support case 1a for positioning the printed circuit boards 2 and 3 must be provided in the lower case 1, and the structure of the lower case 1 Becomes complicated and expensive. In addition, since the press-fit terminal and the conductor made of the plating layer on the inner peripheral surface of the terminal hole of the printed circuit board are connected, it is not suitable for connecting a large current circuit, and the applicable circuit becomes a small and medium current circuit. Receive. Furthermore, in connection with a press-fit terminal, severe dimensional accuracy is required between the press-fit portion of the press-fit terminal and the terminal hole in order to increase the electrical connection reliability with the inner surface of the terminal hole.

JP-A-2005-26052

  The present invention has been made in view of the above problems, and it is an object of the present invention to reduce the size and cost by efficiently connecting the printed circuit boards while configuring the internal circuit of the junction box with the printed circuit boards. It is said.

In order to solve the above-mentioned problems, the present invention stacks two printed circuit boards and accommodates them inside the case of the junction box, and one of the two printed circuit boards has a large conductor thickness. and then, energization amount is set to the thick film substrate provided with a large-current circuit conductors including the power input circuit as more than 20 amps, the other printed board is the conductor thickness small city, energization amount is output circuits as less than 20 amperes A thin film substrate with conductors for small and medium current circuits,
The thick film substrate has a smaller area than the thin film substrate, and in a region where the thick film substrate and the thin film substrate overlap, both substrates are laminated via a spacer and connected to the conductor for the large current circuit on the surface of the thick film substrate. Mounting an electrical component to be mounted on the surface of the thin film substrate and connecting the electrical component to the conductor for the small and medium current circuit;
A vehicle junction box is provided in which electrical components connected to the conductor for the small and medium current circuit are mounted on both surfaces of the thin film substrate other than the region overlapping with the thick film substrate.

The thick film substrate is formed by laminating and integrating copper foil on the surface of the insulating base material, and may be a single-sided substrate in which copper foil is laminated only on one side of the insulating base material, but copper foil is laminated and integrated on both sides. More circuits can be provided by using a double-sided substrate.
The thin film substrate is formed by laminating and integrating copper foils on the surface of an insulating base material, a single-sided substrate in which copper foil is provided only on one surface side of the insulating base material, and a double-sided substrate in which copper foils are laminated and integrated on both sides Furthermore, any of the multilayer substrates in which an insulating base material and a copper foil are sequentially laminated may be used. However, when a large number of circuits are provided, the multilayer substrate is preferable.

In the present invention, as described above, the internal circuit of the junction box is configured by the printed circuit board. Therefore, the circuit can be arranged densely as compared with the bus bar, and the circuit can be thinned and downsized. The amount of current can be easily set to the required amount of current simply by changing the thickness of the conductor. Further, the circuit configuration can be easily changed, and the number of design changes can be reduced.
Also, the thin film substrate that mainly forms the output circuit by reducing the conductor thickness to make the conductor for small and medium current circuits, and the thick film substrate that mainly forms the power input circuit by increasing the conductor thickness and making it the conductor for large current circuits Rather, it is necessary to mount and connect a large number of external electrical components such as connectors. In the present invention, since the thick film substrate is integrated and made smaller than the thin film substrate, the thin film substrate is provided with a region that does not overlap the thick film substrate. As a result, it is possible to mount electrical components with high density inside the case. As a result, the junction box can be reduced in size.
By placing a thick film substrate on one side above the large area thin film substrate, and projecting terminals connected to the conductor on the other side of the thin film substrate and on the opposite side of the thick film substrate Connectors, fuses, relays, etc. can be mounted. In addition, a thick film substrate is placed above the center of the large area thin film substrate, and terminals are provided on the outer side of the thin film substrate that does not overlap with the thick film substrate and on the surface opposite to the thick film substrate. By doing so, the component parts can be mounted.

The connection between the conductors of the thick film substrate and the thin film substrate is achieved by providing through holes that communicate with each other in the vertical direction, passing through the through pins through the through holes, and soldering the conductive pins to the conductors of the thick film substrate and the thin film substrate, respectively. Yes.
With this configuration, the conductors of the thick film substrate and the conductors of the thin film substrate can be electrically connected via the conductive pins without being electrically connected via the plating layer on the inner peripheral surface of the through hole. Therefore, it is not necessary to plate the inner peripheral surface of the through hole, and the plating process can be reduced. In addition, you may plate the internal peripheral surface of a through-hole as needed.

As described above , the energization amount of the conductor of the thick film substrate is 20 amperes or more, while the energization amount of the conductor of the thin film substrate is less than 20 amperes .
With the energization amount, as described above, the thick film substrate is a power input circuit, the thin film substrate becomes suitable one for output circuit.

When a conductor is provided on both sides of one printed circuit board made of the thick film substrate, two large current circuit layers can be formed on the thick film substrate.
Further, even in a single printed circuit board made of a thin film substrate, a large number of small and medium current circuit layers can be formed by using a multilayer substrate structure in which insulating materials and copper foils are alternately arranged.
Therefore, in the case where circuits are provided at a high density while reducing the size of the junction box, it is preferable to employ two printed boards including a thick film substrate having a double-sided substrate and a thin film substrate having a multilayer substrate structure.

  In this way, the thick film substrate for large current and the thin film substrate for small current are arranged separately, the thick film substrate is used for power input, the thin film substrate is used for circuit output, and the electrical components connected to the large current circuit Is arranged on the thick film substrate side, and the electrical components connected to the small and medium current circuit are arranged on the thin film substrate side, the electrical components can be aggregated according to the application along the flow of electricity, enabling efficient arrangement. . As a result, since the space in the junction box can be used efficiently, the junction box can be further reduced in size.

In addition, the thickness and width of the conductor on the printed circuit board can be adjusted relatively easily, and the amount of current applied can be controlled appropriately. Furthermore, since it is possible to change the conductor thickness on the same substrate, it is possible to finely adjust the energization amount according to the circuit, which is advantageous for the bus bar.
In the present invention, by increasing the thickness of the conductor of the thick film substrate or / and widening, the energization amount is 20 amperes or more, and the energization amount can be increased to about 200 amperes. It is used as a substrate for large current.
On the other hand, it is preferable that the amount of current flowing through the conductor of the thin film substrate is less than 20 amperes.
Also, when conductors are provided on both sides of the thick film substrate and the thin film substrate, the thicknesses of the conductors on both the front and back surfaces are changed to vary the energization amount. For example, the upper surface of the thick film substrate is 100 amperes or more and the lower surface is 50 amperes. The upper surface of the thin film substrate may be 10 amperes or more and less than 20 amperes, and the lower surface may be less than 10 amperes and 1 ampere or more.

The conducting pin for connecting the conductors of the thick film substrate and the thin film substrate is provided with an upper projecting portion and a lower projecting portion for positioning at an intermediate position in the length direction, and the upper surface of the upper projecting portion is provided with the upper projecting portion. It is preferable to place the thick film substrate and to place the thin film substrate in contact with the lower surface of the lower protrusion.
With the above configuration, the conductors of the printed circuit boards can be electrically connected by the conductive pins, and the positioning between the printed circuit boards can be performed by the conductive pins, so that a new component such as an insulating plate for positioning becomes unnecessary, and the number of components can be reduced. Can be reduced.

Further, the conductive pin may be protruded into a connector mounted on the printed board and used in combination with the connector pin.
In this way, if the connection pins for connecting the boards are directly projected into the connector to form the connector pins, there is no need to provide a dedicated connector pin to connect to the conductor, thereby reducing the number of parts and the number of work steps. it can.

  As described above, according to the present invention, since the internal circuit of the junction box is formed not by the bus bar but by at least two printed circuit boards including the thick film substrate and the thin film substrate, the circuit is compared with the bus bar. Can be arranged densely, the circuit can be made thin and the size can be reduced, and the allowable current amount can be set to the required current amount only by changing the thickness of the conductor.

In addition, since the thick current substrate for large current and the thin film substrate for small current are arranged separately, the components can be aggregated according to applications, and the printed circuit board can be miniaturized. In particular, since the conductor of the thin film substrate is an output circuit, it is necessary to project a large number of terminals and mount electrical parts such as connectors, fuses, and relays. In the present invention, the thin film substrate is replaced with a thick film substrate. Since the area of the thin film substrate which does not overlap with the thick film substrate is provided in a state where the thick film substrate and the thin film substrate are laminated, the electric components can be mounted on both surfaces of the thin film substrate in the area.
Furthermore, when the conductive pins used together with the connector pins are used as the connection pins for connecting between the boards, there is no need to provide the connector pins on the board, the number of parts can be reduced, and the connector pins and the connection pins can be attached once. This can be done by work, and man-hours can be reduced.

Embodiments of the present invention will be described with reference to the drawings.
1 to 6 show a junction box (hereinafter referred to as a junction box) 10 for a vehicle according to a first embodiment of the present invention, in which two printed boards comprising a thick film substrate 14 and a thin film substrate 15 serving as internal circuits are shown. They are stacked via spacers 11 made of an insulating material and accommodated in the upper case 12 and the lower case 13.

  The thick film substrate 14 has a smaller area than the thin film substrate 15, and in this embodiment, the area of the thick film substrate 14: the area of the thin film substrate 15 = 3: 5, and the spacer 11 is disposed on one side portion 15 x of the thin film substrate 15. The thick film substrate 14 is disposed through the gap. Therefore, the spacer 11 and the thick film substrate 14 do not exist above the other side portion 15y of the thin film substrate 15 and are a space.

  As shown in FIG. 3, the thick film substrate 14 is formed by laminating and integrating conductors 14 b-1 and 14 b-2 made of copper foil having a large thickness on both sides of a flat substrate 14 a made of insulating resin. The board configuration is used. The energization amount of the conductors 14b-1 and 14b-2 of the thick film substrate 14 is 20 amperes or more, and the relay R and the large current terminal T1 connected to the conductors 14b-1 and 14b-2 are provided on the upper surface of the thick film substrate 14. Implemented. The large current terminal T1 is press-fitted into a terminal hole provided in a conductor portion of the thick film substrate 14.

As shown in FIG. 4, the thin film substrate 15 has a larger area than the thick film substrate 14, and has a flat base material 15 a-1 to 15 a-3 made of an insulating resin and a small current for a small thickness. The conductors 15b-1 to 15b-4 are alternately laminated and integrated into a multilayer substrate structure.
The amount of energization of the conductor 15b of the thin film substrate 15 is less than 20 amperes, and the small and medium current terminals T2 connected to the conductor 15b are mounted on the terminal block. The terminal T2 protrudes only on the lower surface side in the region 15x that overlaps with the thick film substrate 14, and in the region 15y that does not overlap with the thick film conductor 14, the small and medium current terminals T2 are connected to the conductors on both surfaces. .
The small / medium current terminal T2 is press-fitted into a terminal hole provided in the terminal block 21 mounted on the substrate to maintain alignment.

  As shown in FIGS. 3 and 4, the thick film substrate 14 and the thin film substrate 15 are provided with through holes 14d and 15d, respectively, through which conductive pins 16 connecting the thick film substrate 14 and the thin film substrate 15 are inserted. . The inner peripheral surfaces of the through holes 14d and 15d are not plated, and the conductors 14b-1 to 14b-2 and 15b-1 to 15b-4 are not conductive when the conductive pin 16 is not inserted. .

  As shown in FIG. 5, the conductive pins 16 are rod-shaped and have a pair of upper protrusions 16a and lower protrusions for positioning the thick film substrate 14 and the thin film substrate 15 with a required interval at an intermediate position in the length direction. 16b is provided, and the upper side of the upper protruding part 16a is an upper surface part 16c, and the lower side of the lower protruding part 16b is a lower surface part 16d.

As shown in FIG. 6, the tips of the conductive pins 16 are inserted into the through holes 14d from the lower surface side of the thick film substrate 14, and the thick film substrate 14 is placed on the upper surface portion 16c of the upper protruding portion 16a, and the thin film Conductive pins 16 are inserted into the through holes from the upper surface side of the substrate 15, and the thin film substrate 15 is disposed in contact with the lower surface portion 16 d of the lower protrusion 16 b, thereby determining the distance between the thick film substrate 14 and the thin film substrate 15.
The conductive pins 16 and the conductors 14b and 15b of the thick film substrate 14 and the thin film substrate 15 are soldered with solder H so that the conductors 14b and 15b and the conductive pins 16 are electrically connected, and at the same time, the thick film substrate 14 and the thin film substrate 15 are connected. And conducting.

  As shown in FIG. 1, a fuse case 19 is mounted on one side surface of a thick film substrate 14 and a thin film substrate 15 that are stacked one above the other, and a fuse assembly 20 in which a large number of fuses 17 are juxtaposed in a lateral direction is mounted on the fuse case 19. It is detachably fitted.

Specifically, a large number of tuning-fork-shaped input-side terminals 18A are solder-connected to the end-side conductors 14b-n connected to the conductors 14b-1 and 14b-2 on both sides of the thick film substrate 14 in a horizontal direction.
Similarly, the thin-film substrate 15 is also solder-connected with a large number of tuning-fork-shaped output-side terminals 18B facing the end-side conductors 15b-n connected to the four layers of conductors 15b-1 to 15b-4.
The input side terminal 18A and the output side terminal 18B arranged side by side are covered with the fuse case 19 having a U-shaped cross section. The fuse case 19 is provided with terminal holes 19a and 19b in parallel on the upper and lower sides, respectively. The input terminal 18A is positioned inside each upper terminal hole 19a, and the output terminal 18B is positioned inside each lower terminal hole 19b.

The fuse assembly 20 is provided with a large number of fuse accommodating portions 20b in a horizontally long frame 20a, and the fuses 17 are accommodated horizontally in the respective fuse accommodating portions 20b.
When the fuse assembly 20 is assembled to the fuse case 19, the input terminal 17a of each fuse 17 is inserted into the upper terminal hole 19a to be fitted and connected to the input terminal 18A, and the output terminal 17b of the fuse 17 is connected to the fuse terminal 19. It is inserted into the lower terminal hole 19b and fitted and connected to the output side terminal 18B.

When the junction box 10 to the configuration, the circuit can be densely arranged a printed circuit board comprising a thick film substrate 14 and the thin film substrate 15. As the internal circuit as compared to the bus bar, it is possible to thin and miniaturize the circuit At the same time, the allowable current amount can be made the required current amount only by changing the thickness of the conductors 14b and 15b. Further, by providing the the positioning conductive pin 16 and the upper protrusion 16a and the lower projecting portion 16b, since the conductive pins 16 to the positioning of the same time the printed circuit plates Connecting printed circuit board, for positioning New parts such as an insulating plate are not necessary, and the number of parts can be reduced.
Moreover, since the separately disposed on the thin film substrate 15 for a small current in the printed circuit board and thick film substrate 14 for a large current, it can aggregate components by application, to reduce the size of the printed circuit board be able to.
Furthermore, the area of the thin film substrate 15 is made larger than the area of the thick film substrate 14, and the thin film substrate 15 is protruded from the thick film substrate 14, so that terminals are provided on both sides of the protruding portion to provide a connector or the like. Can be connected.

FIGS. 7A, 7B, and 7C show a modification of the stacking relationship between the thick film substrate 14 having a small area and the thin film substrate 15 having a large area.
In FIG. 7A, the area of the thick film substrate 14 is made slightly smaller than that of the first embodiment to be ½ of the area of the thin film substrate 15, and the area of the thick film substrate: the area of the thin film substrate = 1: 2. It is said.
In FIG. 7B, the area of the thick film substrate 14 is further reduced to 2/5 of the area of the thin film substrate 15, and the thin film substrate 15 is provided with a non-stacked region in a U-shape. The area of the thin film substrate = 2: 5.
In FIG. 7C, the area of the thick film substrate 14 is 2/5 of the area of the thin film substrate 15, and the thick film substrate 14 is stacked at the center of the thin film substrate 15. A laminated region is provided, and the area of the thick film substrate: the area of the thin film substrate = 2: 5.

  As described above, by appropriately changing the area ratio and the stacking position of the thin film substrate 15 and the thick film substrate 14, it is possible to increase the degree of freedom in designing the arrangement position of the electrical components mounted on the thin film substrate 15 side.

FIG. 8 shows a second embodiment of the present invention, in which a conductive pin 16 ′ protrudes into a connector 30 mounted on the thick film substrate 14 and is used together with the connector pin.
According to this configuration, since the connection pins and the connector pins for connecting the boards are used in combination as the conductive pins 16, it is not necessary to provide the connector pins on the board, the number of parts can be reduced, and the connector pins and the connection pins. Can be attached in one operation, and the number of man-hours can be reduced.
Since the configuration other than the conductive pins is the same as that of the first embodiment, a description thereof will be omitted.

It is a disassembled perspective view of the junction box concerning a 1st embodiment of the present invention. It is sectional drawing in the state which removed the case of 1st Embodiment. It is sectional drawing of a thick film board | substrate. It is sectional drawing of a thin film substrate. It is a perspective view of a conductive pin. It is sectional drawing to which the principal part of the state which connected the conductive pin and the printed circuit board and soldered was expanded. (A), (B), and (C) are drawings showing modifications in which the area ratio and the lamination state of the thick film substrate and the thin film substrate are changed. It is a figure of 2nd Embodiment. The figure of a prior art example is shown, (A) is a disassembled perspective view of a junction box, (B) is sectional drawing to which the principal part was expanded.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Junction box 11 Spacer 12 Upper case 13 Lower case 14 Thick film board 15 Thin film board 16 Conductive pin 17 Fuse 17 a Input terminal 17 b Output terminal 18A, 18B Tuning fork-shaped terminal 19 Fuse case H Solder

Claims (4)

By laminating two printed circuit boards housed inside the case Ja action box, among these two printed circuit boards, one of the printed circuit board conductor thickness large cities, energization amount is power input as above 20 amps A thick film substrate provided with a conductor for large current circuits including a circuit, and a thin film substrate provided with a conductor for small and medium current circuits for an output circuit, with the other printed circuit board having a small conductor thickness and an energization amount of less than 20 amperes. ,
The thick film substrate has a smaller area than the thin film substrate, and in a region where the thick film substrate and the thin film substrate overlap, both substrates are laminated via a spacer and connected to the conductor for the large current circuit on the surface of the thick film substrate. Mounting an electrical component to be mounted on the surface of the thin film substrate and connecting the electrical component to the conductor for the small and medium current circuit;
An electric junction box for mounting a vehicle on both sides of the thin film substrate other than the region overlapping with the thick film substrate is connected to the small and medium current circuit conductor.   The connection between the conductors of the thick film substrate and the thin film substrate is achieved by providing through holes that communicate with each other in the vertical direction, passing through the through pins through the through holes, and soldering the conductive pins to the conductors of the thick film substrate and the thin film substrate, respectively. The vehicle junction box according to claim 1. An upper projecting portion and a lower projecting portion for positioning are provided at an intermediate position in the longitudinal direction of the conductive pin, and the thick film substrate is placed on the upper surface of the upper projecting portion, and the lower surface of the lower projecting portion The vehicle junction box according to claim 2 , wherein the thin film substrate is disposed in contact with the vehicle. 4. The vehicle junction box according to claim 2 , wherein the conductive pin protrudes into a connector mounted on the printed circuit board and is used together with the connector pin . 5.

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