JP3498668B2 - Wiring board of electrical junction box - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wiring board of an electric junction box provided with a wiring portion composed of a bus bar. 2. Description of the Related Art Conventionally, an electric connection box such as a relay box and a fuse box mounted on a vehicle includes a wiring assembly in which a plurality of wiring boards are stacked. Each wiring board includes an insulating substrate made of a synthetic resin, and a wiring portion including a plurality of bus bars is formed on the insulating substrate. On the insulating substrate,
Protrusions that partition between adjacent bus bars are integrally formed. The ridge is formed at a height equal to or greater than the thickness of the bus bar. The lower surface of another wiring board laminated on the wiring board is in contact with the upper end of the ridge.
Therefore, adjacent bus bars are arranged in each space defined by the ridge between the upper and lower wiring boards. However, since the ridges and the upper wiring board do not always adhere to each other, the bus bars defined by the ridges are not reliably isolated from each other. For this reason, there is a possibility that the bus bars are electrically short-circuited by dew condensation water or water entering from the outside, and a leak current flows. As a technique for preventing such a short circuit between bus bars, a bus bar wiring board disclosed in Japanese Utility Model Laid-Open No. 63-90921 and an electric connection box disclosed in Japanese Patent Application Laid-Open No. 7-336843 have been proposed. In the wiring board disclosed in Japanese Utility Model Laid-Open Publication No. 63-90921, as shown in FIG. 7 , by raising the ridge 41 between the adjacent bus bars 40, water droplets straddle the ridge 41 to form the bus bars 40. To prevent leakage current. [0006] In the electrical connection box of JP-A-7-336843 discloses, as shown in FIG. 8, the adjacent bus 5
The gap between zeros is filled with a flexible insulating sealing material 51, and the lower surface of the upper wiring board 52 is brought into close contact with the insulating sealing material 51. This ensures that the bus bars 50 are isolated from each other by the insulating sealing material 51, and that no leak current flows. [0007] According to each of these techniques, it is possible to prevent leakage current from flowing into each bus bar due to dew condensation water or infiltration water. [0008] In recent years, studies have been made on increasing the voltage of a vehicle-mounted battery, and the voltage supplied to the electric junction box has been reduced from the conventional voltage of 14 V or less to, for example, 42%.
V. When the voltage becomes 42V, the magnitude of the leak current due to the short circuit between the bus bars becomes 4 to 5 times that at 14V. For this reason, not only when the bus bars are communicated with each other by dew or the like, but also when the insulating substrate is wet between the bus bars, a leak current of a magnitude that cannot be ignored flows. However, in the case of the bus bar wiring board disclosed in Japanese Utility Model Laid-Open Publication No. 63-90921, in order to prevent a leak current at a high voltage, the height of the ridge 41 is compared with the thickness of the bus bar 40. Must be significantly higher. as a result,
There is a problem that the thickness of the wiring board is increased and the height of a wiring assembly formed by laminating a plurality of wiring boards is increased. On the other hand, in the case of the electric connection box disclosed in Japanese Patent Application Laid-Open No. 7-336843, in order to prevent a leakage current at the time of a high voltage, an operation of filling the gap between all adjacent bus bars 50 with the insulating sealing material 51 is required. Need to do. as a result,
When the number of the bus bars 50 is large, there is a problem that the filling operation requires a long time and the manufacturing efficiency is reduced. SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and an object of the present invention is to prevent leakage of water into a bus bar due to dew condensation or the like without increasing the thickness of a wiring board or reducing manufacturing efficiency. An object of the present invention is to provide a wiring board of an electric junction box which can prevent a current from flowing more reliably. [0012] [Means for Solving the Problems] To solve the above problems, a first aspect of the present invention, in the wiring board of the electrical junction box busbars are wired on the insulating substrate, the bus bar
In a state where multiple busbars are connected by the connecting part
It is stamped and formed in one piece, and
Except for the connection part to which the external terminal is connected while being connected, the entire part is covered with insulating coating, and the connection part is removed.
The exposed end face exposed to the outside by removing
Formed integrally with each other, and between the opposed exposed end faces.
Insulation that fuses a pair of melting protrusions provided on both sides
A wiring board for an electric wiring box, wherein the wiring board is insulated and coated on an insulating substrate with a conductive resin . According to the present invention, the bus bar wired on the insulating substrate and another conductive member are electrically insulated by the bus bar being insulated and coated. Therefore, the protrusion does not need to be thicker than the busbar for insulation, so that the thickness does not increase. Further, since there is no need to perform an operation of filling the insulating seal material between the bus bars, a long operation time is not required even if the number of bus bars is increased. still,
The other conductive members include other busbars, single core wires, pressure contact terminals, and the like wired on the same insulating substrate, and busbar tabs and pressure contact terminal connection tabs wired on the other insulating substrate. Ma
In addition, it is punched out integrally with the connection part
The insulating substrate
Each bus bar wired above can be removed by removing the connection
The exposed end face exposed to the outside is insulated on the insulating substrate
Thus, the whole is insulated. And the whole is insulation coating
The insulation between the busbar and other conductive members.
You. Therefore, multiple busbars wired on the same insulating substrate
Can be stamped and formed integrally from one sheet of metal
It becomes possible. In addition, cover the exposed end faces of the busbars with insulation.
Insulating resin must be supplied in a fluid state from outside
No need. Moreover, a convex portion for melting is provided between the exposed end faces facing each other.
Compared to the case where one is provided
The insulating coating can be more reliably performed by the grease. An embodiment of the present invention will be described below with reference to FIGS. 1 to 6. As shown in FIG. 2, one wiring board 1 provided in an electric connection box (not shown)
No. 0 has an insulating substrate 11 made of an insulating thermoplastic resin. Examples of the insulating thermoplastic resin forming the insulating substrate 11 include talc-containing polypropylene. On the upper surface 11a as a wiring surface of the insulating substrate 11, a protruding portion 12 is formed at the same height along the entire periphery thereof. In addition, the first and second sections are formed on the entire area surrounded by the protrusions 12 on the upper surface 11a of the insulating substrate 11.
The wiring portion 15 including the bus bars 13 and 14 is formed. The protruding portion 12 includes first and second bus bars 13, 1.
4 is formed higher than the thickness. FIG. 2 is a schematic diagram. In practice, a large number of bus bars are wired on the entire upper surface 11a of the insulating substrate 11. In the present embodiment,
The bus bar 13 and the bus bar 14 both wired on the same insulating substrate 11 are independent conductive members. The wiring board 10 is laminated with a plurality of wiring boards similarly formed to form a wiring assembly. Then, a known lower case (not shown) is mounted below the wiring assembly, and an upper case (not shown) is mounted above the wiring assembly, thereby forming an electric connection box. At this time, the tab of each bus bar wired to each wiring board extends downward from the lower surface of the wiring assembly by penetrating each wiring board below the wiring board. Similarly, the tab of each bus bar wired to each wiring board extends upward from the upper surface of the wiring assembly through each wiring board in a layer above the wiring board. The tab of each bus bar extending from the lower surface of the wiring assembly serves as a male terminal of a connector housing formed in, for example, a lower case. or,
For example, a relay relay terminal serving as a female terminal of a relay housing formed in the upper case is connected to a tab of each bus bar extending from the upper surface of the wiring assembly. On the upper side of the wiring board 10, the lower surface of the upper wiring board is in contact with the upper end of the protruding portion 12 thereof. That is, the upper wiring board is stacked on the wiring board 10 without directly contacting the upper surfaces of the first and second bus bars 13 and 14. As shown in FIGS. 1 (a), 1 (b) and 2, the first and second bus bars 13, 14 are entirely formed except for tabs 13a, 14a as connecting portions to which external terminals are connected. It is insulated and covered by an insulating film 16 and an insulating portion 17 made of an insulating resin. The insulating film 16 is formed of an insulating resin, such as a urethane-based synthetic resin, which becomes liquid at a high temperature and can be attached to the bus bars 13, 14. The space between the first and second bus bars 13 and 14 is
It is electrically insulated by the insulating film 16 and the insulating portion 17. That is, water existing on the upper surface 11a of the insulating substrate 11, that is, dew condensation water, intruding water from the outside, or
The busbars 13 and 14 are not electrically short-circuited by the humidity a. Next, a method of manufacturing the wiring board 10 will be described.
First, as shown in FIG. 3, the first and second bus bars 13 and 14 to be assembled on the same insulating substrate 11 are connected to one metal plate in a state where both bus bars 13 and 14 are connected to each other by a connecting portion 18. And punched together. The first and second bus bars 13 and 14 are formed on the punched member in the same arrangement relationship as the wiring on the insulating substrate 11. Then, the entire first and second bus bars 13 and 14 connected to each other by the connecting portion 18 are insulated and coated with an insulating resin, and an insulating film 16 is formed on the entire bus bars 13 and 14. At this time, both bus bars 13, 1
The tabs 13a and 14a (shown in FIG. 2) are masked so that the insulating film 16 is not formed. Next, as shown in FIG. 4, the connecting portion 18 is removed to separate the first and second bus bars 13 and 14 from each other. Then, the end faces of the first and second bus bars 13 and 14 from which the connecting portion 18 has been removed are exposed to the outside as exposed end faces 13b and 14b which are not covered with the insulating film 16. Next, as shown in FIG.
The second bus bars 13 and 14 are assembled and fixed on the insulating substrate 11 by caulking or the like. Then, the exposed end faces 13 b and 14 b of the first and second bus bars 13 and 14 connected to each other by the connecting portion 18 are arranged at positions facing each other on the insulating substrate 11. Here, the exposed end faces 13 of the first and second bus bars 13 and 14 which are wired to the insulating substrate 11 are opposed to each other.
b, 14b, a pair of melting protrusions 1
9 is integrally formed on the insulating substrate 11 in advance. Next, as shown in FIG.
9 is melted, and an insulating portion 17 for insulatingly coating between the exposed end faces 13b and 14b is formed by the melted projections 19 (made of insulating resin). Each melting protrusion 19
Are simultaneously melted by pressing the heating jig from above. Through the above steps, the entire bus bars 13 and 14 wired on the wiring board 10 are insulated and covered by the insulating film 16 and the insulating portion 17. The wiring board of the electrical junction box of the present embodiment described above has the following effects. (1) In the present embodiment, the bus bars 13 and 14 are electrically insulated by the insulating film 16 formed before the wiring and the insulating portion 17 formed after the wiring. Therefore, it is not necessary to provide a significantly high ridge between the bus bars 13 and 14, so that the thickness of the wiring board 10 does not increase. Further, since the work of filling the gap between the adjacent bus bars 13 and 14 with the insulating sealing material is not performed, the assembling work time does not increase even if the number of bus bars forming the wiring portion 15 increases. For this reason, it is possible to reliably prevent the leakage current from flowing between the first and second bus bars 13 and 14 due to the dew water or the like without increasing the thickness of the wiring board 10 or lowering the manufacturing efficiency. . Even if the voltage supplied to the electric connection box is increased from 12 V to, for example, 42 V, it is possible to prevent a leak current from flowing between the first and second bus bars 13 and 14. (2) In addition, in the present embodiment, the first and second bus bars 13, which are wired on the same insulating substrate 11,
An insulating film 16 was formed on the entire surface of a single metal sheet 14 formed by stamping. And the connecting part 1
Exposed end faces 13b, 14b formed by removing 8
Was insulated by an insulating portion 17 on an insulating substrate 11.
Therefore, the first and second busbars 13 and 14 to be assembled on the same insulating substrate 11 can be integrally formed by punching out a single metal plate material. Therefore, even when there are many types of busbars to be wired, At the time of manufacturing, various types of bus bars can be easily managed and assembled. (3) In addition, in the present embodiment, the first and second surfaces are provided on the upper surface 11a of the insulating substrate 11 along the entire periphery.
The protrusions 12 are higher than the thicknesses of the bus bars 13, 14, and the lower surface of the wiring board, which is an upper layer during lamination, is brought into contact with the upper end of the protrusions 12. Therefore, the insulating film 16 formed on the upper surfaces of the first and second bus bars 13 and 14
Since the lower surface of the upper wiring board does not contact, the insulating film 16 is not damaged by abrasion. Further, since the thickness of the wiring board 10 is equal to the height of the protruding portion 12, even if the thickness of the insulating film 16 varies, the thickness of the wiring board 10 does not vary. As a result, in a wiring assembly formed by stacking a plurality of wiring boards formed in the same manner as the wiring board 10, it is possible to suppress variations in the length in the stacking direction. (4) In the present embodiment, in addition, in the insulating substrate 11 made of a thermoplastic resin, the melting protrusions 19 are previously formed integrally, and the melting protrusions 19 are melted.
Thus, the exposed end faces 13b and 14b are insulated. Therefore, it is not necessary to supply the insulating resin for insulatingly covering each of the exposed end faces 13b and 14b from the outside in a flowing state, so that a facility for supplying the insulating resin is not required. (5) In addition, in the present embodiment, a pair of melting projections 19 for insulatingly covering both exposed end faces 13b and 14b located in the opposite state are provided on both sides between the two. Therefore, as compared with the case where one melting convex portion is provided between the two, the insulating coating can be more reliably performed by the insulating resin melted from two places. Hereinafter, embodiments of the invention other than the above embodiment will be described . In the above embodiment, the present invention is applied to the wiring board 10 on which the wiring portion 15 including the first and second bus bars 13 and 14 is formed. However, the present invention may be applied to a wiring board on which a wiring portion including three or more bus bars is formed. Hereinafter, technical ideas that can be grasped from the above-described embodiments and other examples will be described together with their effects . ( 1 ) In the invention according to claim 1, the wiring surface (upper surface 13 a) of the insulating substrate on which the bus bar is wired has a protruding portion that is higher than the thickness of the bus bar. The wiring board of the electric junction box in which is formed. According to such a configuration, it is possible to prevent the insulating coating of the bus bar from being damaged, and it is possible to reliably prevent the leakage current from flowing through the bus bar. Further, since the thickness of the wiring position is determined by the height of the protruding portion, it is possible to suppress variations in the thickness. According to the first aspect of the present invention, the leak current does not more reliably flow into the bus bar due to dew water or the like without increasing the thickness of the wiring board or lowering the manufacturing efficiency. You can do so. Also, connect the wiring to the same wiring board.
A plurality of bus bars from a single metal plate
Management and assembly of various types of busbars
Can be easily performed. In addition, the busbar is isolated
There is no need to supply insulating resin for coating from outside.
Therefore, there is no need for an insulating resin supply facility. Only
In the case where one melting protrusion is provided between the exposed end faces facing each other,
Insulated with molten resin from both sides
Coating can be performed more reliably. [0050]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 (a) is a schematic plan view showing a part of a wiring board of the present embodiment, and FIG. 1 (b) is a schematic cross-sectional view taken along line AA of FIG. FIG. 2 is a schematic perspective view showing a wiring board. FIG. 3 is a schematic perspective view showing a part of a bus bar. FIG. 4 is a schematic perspective view showing a part of a bus bar. FIG. 5 is a schematic perspective view showing a part of an insulating substrate on which a bus bar is assembled. FIG. 6 is a schematic perspective view showing a part of an insulating substrate. FIG. 7 is a schematic sectional view showing a part of a conventional wiring board. FIG. 8 is a schematic sectional view showing a part of a conventional wiring board. [Description of Reference Numerals] 10: wiring board, 11: insulating substrate, 13: first bus bar as a conductive member, 13a: tab as a connection portion, 13
b ... exposed end face, 14 ... second bus bar as conductive member, 14a ... tab as connection part, 14b ... exposed end face,
18: connecting part, 19: convex part for melting.

──────────────────────────────────────────────────続 き Continued on front page (58) Field surveyed (Int. Cl. ⁷ , DB name) H02G 3/16 B60R 16/02

Claims (1)

(57) Claims 1. In a wiring board of an electric junction box in which bus bars are wired on an insulating substrate, the bus bars are connected by a connecting portion.
In this state, it is punched and formed
Except for the connection part to which the external terminal is connected while being connected by the connection part, the whole is insulated and coated, and the exposed end face exposed to the outside by removing the connection part is
The insulating substrate is formed integrally, and the opposing
The melting protrusions provided as a pair on both sides between the exposed end faces
Insulated coating on insulating substrate with molten insulating resin
Wiring board of the electrical connection box, characterized in that is.