JP2007227169A - Bus bar and electrical junction box - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a bus bar and an electrical junction box wherein size reduction of a wiring circuit board and wiring property improvement of conductive pattern can be attained. <P>SOLUTION: In front of the bus bars 3 supported on the wiring circuit board 2 parallel to the wiring circuit board 2, reverse L-shaped branch pieces 8 are projected and installed in a pair respectively coping with the mounting parts such as a relay mounted on the wiring circuit board 2. In this branch piece 8, a press-fit terminal 9 is formed at the lower end, and by press-fitting the crimping parts 10 of the tip part of the press-fit terminal 9, respectively, into through-holes 14, 14 formed on the conductive pattern of the mounting parts, power transmission from the bus bar 3 to the circuit on the wiring circuit board 2 is enabled. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a bus bar used as a power transmission path in an electric junction box mounted on an automobile, and an electric junction box in which the bus bar is used.

The electric junction box for automobiles connects / disconnects between the power source of the on-board battery and the electronic control unit for the engine or the electronic control unit for the air bag, which is an electric load, to supply power to each electronic control unit. In a well-known device to be controlled, a wiring board on which electronic parts such as a microcomputer and a relay are mounted and a predetermined circuit is formed is connected to a power supply in addition to a board connector to which a wire harness connector for connecting an electronic control unit is connected. There is provided a bus bar which is connected to the connection terminal and supplied with power.
As the shape of this bus bar, the one shown in Patent Document 1 is known. As shown in FIG. 2, the bus bar 21 disclosed in Patent Document 1 includes a board connection terminal 22 that is screwed and soldered directly to the bus bar connection terminal part of the wiring board 20 at one end in the longitudinal direction. The other end has an inverted L shape that is supported in parallel with the wiring board 20. 23, 23,... Fuse connection fuse terminals integrally formed at the longitudinal edges, and 24 is protruded from the board connection terminal 22 so as to be connected to a connection terminal from a power source. Power supply terminal.

JP 2006-42586 A

  When such a bus bar 21 is used, as shown in FIG. 3B, the wiring board 20 has a mounting part 28 such as a relay mounted on the wiring board 20 from the bus bar connection terminal portion 25 provided at the corner. , 28..., First, the conductive pattern 26 is formed over substantially the entire length of one side of the wiring board 20, and then the distribution portions 27, 27. . Therefore, the occupied portion on the wiring board 20 is large, and the layout of other conductive patterns is lowered due to the restrictions on the layout on the wiring board 20. If it is intended to improve the routing property, the wiring board 20 is increased in size.

  Therefore, an object of the present invention is to provide a bus bar and an electrical junction box that can achieve both miniaturization of a wiring board and improvement in the wiring property of a conductive pattern.

In order to achieve the above object, the invention described in claim 1 is a bus bar supported on a wiring board in parallel with the wiring board and having a power supply terminal at an end, and a plurality of press bars having a press-fit terminal at the lower end. The branch piece is integrally formed, and a press-fit terminal is press-fitted into a through hole provided in the circuit on the wiring board, thereby enabling direct electrical connection to the circuit on the wiring board via the branch piece. It is characterized by.
In addition to the object of the first aspect, the invention according to the second aspect is arranged in such a manner that the branch pieces are arranged on one end edge in order to enable more rational use of the bus bar in the wiring board on which the fuse is mounted. And a fuse terminal to which a fuse can be connected is formed at the other edge.

  In order to achieve the above object, an invention according to claim 3 is an electric junction box for automobiles, and has a through hole at a predetermined position of a circuit on a wiring board. The bus bar is assembled in parallel with the wiring board, and the press-fit terminal of the branch piece is press-fitted into the corresponding through hole, so that the bus bar is directly electrically connected to the circuit through the branch piece.

According to the first and third aspects of the present invention, since the bus bar can be directly electrically connected to the circuit on the wiring board, it is not necessary to form a conductive pattern for power transmission to each circuit on the wiring board. Therefore, it is possible to achieve a reduction in the size of the wiring board and, in turn, a compact electrical connection box. On the other hand, if the wiring boards have the same size, the layout can be afforded, so that the pattern routing is improved.
In addition, by adopting the branch piece and the press-fit terminal, it is not necessary to connect to the wiring board with screws or solder, so that the flow process can be omitted, and the manufacturing process can be simplified and cost reduction can be expected. In particular, the omission of the flow process eliminates the need to use a heat resistant resin for the housing of the board connector, and an inexpensive polyamide-based resin or the like can be employed, leading to further cost reduction.
According to the second aspect of the present invention, in addition to the effect of the first aspect, by providing the fuse terminal at the edge of the bus bar, a part of the fuse circuit formed on the wiring board is provided on the bus bar side. Can be formed. Therefore, even if a fuse is mounted, a rational layout is possible without increasing the size of the wiring board.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a perspective view showing an example of an electric junction box for automobiles in which the bus bar of the present invention is used. The electrical connection box 1 controls the power supply to each electronic control unit by connecting / disconnecting between the power source of the on-vehicle battery and the engine electronic control unit, the airbag electronic control unit, and the like serving as an electric load. In a well-known device, a wire connecting an electronic control unit with a bus bar 3 to which power is supplied from the outside to a planar rectangular wiring board 2 on which electronic components such as a microcomputer and a semiconductor relay are mounted to form a predetermined circuit. Board connectors 4, 4 and the like to which the harness connectors are connected are assembled. These components are entirely covered by an upper and lower cover (not shown) except for a wire harness, a fuse connecting portion, and the like.

  The bus bar 3 is a conductive metal plate supported in parallel with the wiring board 2 above the insulating housing 5 fixed on the wiring board 2, and has a connection terminal from a power source on one end side in the longitudinal direction. A power supply terminal 6 to which is connected is projected. A plurality of fuse terminals 7, 7,... Paired with fuse terminals (not shown) are provided at the rear edge of the bus bar 3 (explained assuming that the edge side of the wiring board 2 is the rear and the center side is the front). On the other hand, a pair of inverted L-shaped branch pieces 8, 8.. Project from the front edge in accordance with mounting components such as relays mounted on the wiring board 2. Has been. This branch piece 8 has a press-fit terminal 9 formed at the lower end, and press-contact of the tip of the press-fit terminal 9 to the through holes 14 and 14 formed on the conductive pattern 13 to the mounting component 12 shown in FIG. Each part 10 is press-fitted to enable power transmission from the bus bar 3 to the circuit on the wiring board 2.

  As the shape of the press contact portion 10 of the press-fit terminal 9, a pair of elastic portions are formed bulging across a central space, and the elastic portion is elastically deformed in a press-fitted state into the through hole, and the inner peripheral surface of the through hole is electrically connected. A pair of abutment parts bulge across the so-called needle-eye shape and the central inclined connecting part, and the abutment part elastically deforms in the press-fitted state into the through hole, and the through hole inner peripheral surface A well-known device such as a so-called N-type shape that is electrically connected to the device is employed. Reference numeral 11 denotes a receiving portion that is provided above the press contact portion 10 and serves as a jig pad during press fitting.

  In the electrical junction box 1 configured as described above, electricity supplied from the power supply terminal 6 of the bus bar 3 flows to a circuit on the wiring board 2 through a fuse (not shown) attached to the fuse terminals 7, 7. On the other hand, it is directly supplied to the conductive patterns 13, 13... On the wiring board 2 through each branch piece 8 and flows to the mounting component 12 or the like. Therefore, in the wiring board 2, a conductive pattern for power transmission from the bus bar connection terminal portion provided in the past to each circuit is unnecessary, and for example, another conductive pattern 15 is formed so as to bypass the mounting component 12. Even under 3, other circuits can be routed.

Thus, according to the bus bar 3 and the electrical junction box 1 of the above-described form, a plurality of branch pieces 8 each having a press-fit terminal 9 at the lower end are integrally formed, and a through hole provided in a circuit on the wiring board 2 The press-fit terminals 9 are press-fitted into the circuit board 14 so as to be directly electrically connected to the circuit on the wiring board 2 via the branch piece 8, thereby forming a conductive pattern for power transmission to each circuit on the wiring board 2. There is no need to do it. Therefore, it is possible to achieve downsizing of the wiring board 2 and consequently compactness of the electrical junction box 1. On the other hand, if the wiring boards have the same size, the layout can be afforded, so that the pattern routing is improved. These effects are apparent when compared with the conductive pattern of FIG.
Further, since the branch piece 8 and the press-fit terminal 9 are used, it is not necessary to connect to the wiring board 2 with screws or solder, so that the flow process can be omitted, and the manufacturing process can be simplified and cost reduction can be expected. In particular, the omission of the flow process eliminates the need to use a heat-resistant SPS resin for the housing of the board connector, and an inexpensive polyamide-based resin or the like can be employed, leading to further cost reduction.

  Here, the branch piece 8 in the bus bar 3 is juxtaposed on one end edge, and the fuse terminal 7 to which a fuse can be connected is formed on the other end edge, so that it is formed on the wiring board 2. A part of the fuse circuit can be formed on the bus bar 3 side. Therefore, a rational layout is possible without increasing the size of the wiring board 2 even if a fuse is mounted.

Note that the branch piece is not limited to the above form, and the length, thickness, number, and the like can be changed as appropriate according to the circuit on the wiring board, and are not inverted L-shaped, and go down directly from the edge of the bus bar. It is also conceivable to make such a change as to form such that it is formed in such a manner as to be raised from the bus bar.
The fuse terminal is not necessarily provided on the bus bar. If there is a margin in the wiring board, the fuse terminal of the bus bar may be omitted and a fuse circuit may be formed on the wiring board side. In this case, the branch piece is not limited to be arranged in parallel at one end edge, but can be appropriately arranged at both end edges.

It is a perspective view which shows an example of a bus bar and an electrical junction box. It is explanatory drawing of the wiring board with which the conventional bus bar is assembled | attached. It is explanatory drawing of the conductive pattern of a wiring board, (A) shows the case where the bus bar of the said form is used, (B) shows the case where the conventional bus bar shown in FIG. 2 is used, respectively.

Explanation of symbols

1 .... Electrical connection box 2 .... Wiring board 3 .... Bus bar 6 .... Power supply terminal 7 .... Fuse terminal 8 ... Branch piece 9 ... Press fit terminal 10 ... Press contact 13 , 15 .. Conductive pattern.

Claims (3)

A bus bar supported on the wiring board in parallel with the wiring board and having a power terminal at the end,
A plurality of branch pieces each having a press-fit terminal at a lower end are integrally formed, and the press-fit terminal is press-fitted into a through hole provided in a circuit on the wiring board, whereby the wiring board is inserted through the branch piece. A bus bar characterized in that it can be directly electrically connected to the above circuit.   The bus bar according to claim 1, wherein the branch pieces are arranged in parallel on one end edge, and a fuse terminal to which a fuse can be connected is formed on the other end edge. A through hole is provided at a predetermined position of a circuit on the wiring board, the bus bar according to claim 1 or 2 is assembled in parallel with the wiring board, and a press-fit terminal of the branch piece is press-fitted into the corresponding through hole. An electric junction box for automobiles in which the bus bar is directly electrically connected to the circuit via the branch piece.

Images