JP2002034132A - Electrical junction box for high voltage - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent generation of leakage current between a plurality of bus bars, at which different voltages are applied inside an electrical junction box. SOLUTION: This electrical junction box comprises a first case 6, accommodating a low-voltage bus bar to which maximum voltage of 14 V or 28 V is applied, and a second case 7, accommodating a high-voltage bus bar to which a voltage higher than the applied voltage of the low-voltage bus bar but lower than or equal to 200 V is applied. The first case 6 and the second case 7 are accommodated in a lower cover 20, which is formed with a partition wall 20b standing from a bottom wall 20a. The first case 6 is disposed inside one-side accommodating chamber 20d surrounded by the partition wall 20b and a peripheral wall 20c, and the second case 7 is disposed inside the other accommodating chamber 20e. The cases are disposed parallel to each other, and a sealing member 25a is interposed between the top ends of the peripheral wall 20c and the partition wall 20b of the lower cover 20, so as to have an upper cover.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a high-voltage electrical junction box mounted on an automobile.

[0002]

2. Description of the Related Art Conventionally, a passenger car of an internal combustion engine generally has one battery with a rated voltage of 12 V and a maximum voltage of 14 V, and a voltage of a maximum of 14 V is supplied from the battery to a circuit such as a bus bar in an electric connection box. The power is distributed by the internal circuit of the electric connection box, and the electric components mounted on the vehicle are controlled and the signals are transmitted and received through the electric wires connected to the internal circuit. In some cases, a rated voltage of 24 V and a maximum voltage of 28 V are applied to the track.

In recent years, the number of electrical components mounted on automobiles has increased rapidly, and the amount of current supplied to one electrical component tends to increase. For example, the power required to drive a fan has conventionally been 130 watts. However, in recent years it has been 260 watts. Further, an intake / exhaust device for an engine requiring a high voltage such as 36 V, an electric power steering, etc. are rated 1
It cannot be operated with a 2V battery power supply, and is therefore operated mechanically by the driving force of the engine.

[0004] As described above, the diameter of the electric wire is increased as the required current amount of the single electric component is increased, and the number of electric wires is increased due to the rapid increase of the electric component. . As a result, the weight of electric wires routed to the vehicle increases. Also, as in the case of the above-mentioned engine intake / exhaust device, it cannot be operated with a power supply from a battery due to a large required power, and if it is operated mechanically, fine intake / exhaust control cannot be performed, and fuel consumption becomes poor. It is not preferable from the viewpoint of environment. Therefore, it is preferable that the intake / exhaust device or the like which has been conventionally operated by a mechanical cam be electrically driven by a power source from a battery as much as possible.

[0005] In view of the above, in a car, a voltage of up to 14 V from a generally mounted battery is used,
By increasing the voltage so that a voltage higher than the voltage can be applied, the required current amount can be reduced, and accordingly, the wire diameter can be reduced and the wire bundle (wire harness) can be reduced, and the wire weight can be reduced. Can be planned. In addition, the intake and exhaust system and power steering of the above-mentioned engine, which were conventionally operated mechanically or hydraulically, can be electrically controlled, and accordingly, fine control of the intake and exhaust system is possible, and the fuel efficiency is improved and the environment is improved. Can be better.

[0006]

As described above, it is preferable to apply a high voltage of about 42 V to the electric power steering, the engine intake / exhaust device, the fan, etc., which require a large amount of electric power, while the signal system and relay of the electric parts are preferably applied. In general passenger cars, the coil and the like have the same rated power of 12 V (maximum voltage of 14
V).

Accordingly, a circuit in which a low voltage of a maximum voltage of 14 V is applied to a circuit of an electric junction box for distributing power,
When a circuit to which a high voltage of about V is applied is provided, a leakage current due to a potential difference is likely to occur. Further, there is a problem that a leak current easily occurs even between circuits to which a high voltage such as 42 V is applied. Furthermore, if water is flooded between bus bars to which a high voltage of about 42 V is applied, there is a problem that a leak current is particularly likely to occur between these bus bars.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems. When a circuit to which a low voltage is applied and a circuit to which a high voltage is applied are provided, it is possible to prevent the occurrence of a leak current and to provide a high voltage. It is an object of the present invention to ensure that no inundation occurs on the bus bar side to which is applied.

[0009]

In order to solve the above-mentioned problems, the present invention provides a first case containing a low-voltage bus bar to which a maximum voltage of 14 V or 28 V is applied; Greater than the applied voltage of 200
A second case accommodating a high-voltage bus bar to which a voltage equal to or lower than V is applied; a first case and a second case accommodated in a lower cover; A wall is provided, and the first case is arranged in one accommodation room surrounded by the partition wall and the peripheral wall, and the second case is arranged and arranged in parallel in the other accommodation room,
Further, the present invention provides a high-voltage electrical connection box in which an upper cover is covered with a sealant interposed between the upper end of the peripheral wall and the upper end of the partition wall of the lower cover.

[0010] As described above, first, the high-voltage busbar and the low-voltage busbar, in which leakage current is likely to occur when adjacently arranged, are housed in separate cases so as not to be adjacent to each other.
In addition, since these cases are blocked by the partition wall projecting from the bottom wall of the lower cover, it is possible to prevent the occurrence of a leak current between the low-voltage bus bar and the high-voltage bus bar. Note that the partition wall may be provided so as to hang down from the upper cover side. Further, since the sealing material is interposed between the lower cover and the upper cover, it is possible to reliably prevent water from entering into the accommodation portions on both sides accommodating the bus bar.

As the above-mentioned sealing material, rubber packing may be used, or silicon may be applied to the joint surface between the peripheral wall of the upper cover and the peripheral wall of the lower cover, and the joint between the upper surface of the partition wall and the inner surface of the upper cover. You may.

The electric wires connected to the bus bars of the first case and the second case disposed in the accommodation room are drawn out through electric wire insertion openings provided in the bottom wall of the lower cover, and are drawn out to the outside.
In addition, a grommet is attached to the electric wire on the second case side containing the high-voltage bus bar, and the grommet is attached to the electric wire insertion opening. Thus, when the grommet is attached to the electric wire connected to the high-voltage bus bar and attached to the electric wire insertion opening of the lower cover, the housing side of the high-voltage bus bar is completely closed, and the occurrence of water intrusion can be reliably prevented. . As a result, it is possible to prevent a leak current from being generated between the high-voltage bus bars.

The low-voltage busbar and the high-voltage busbar are fixed on the insulating plate by inserting ribs projecting from the insulating plate into holes formed in these busbars and caulking. . The insulating plates to which the bus bars are fixed are stacked and arranged inside the first case and the second case.

Preferably, the high voltage is 42V. The reason why the voltage is set to 42V is that if three batteries having a rated voltage of 12V (maximum voltage of 14V), which are widely used in general passenger cars, are connected in series and used, the voltage can be easily increased to 42V. It goes without saying that one battery with a maximum voltage of 42 V may be provided. The reason why the maximum voltage is set to 42 V is that if the voltage is raised to more than 50 V beyond 42 V, it is dangerous if a person accidentally touches it. Further, as a result of the present inventor fitting the terminal connected to the electric wire terminal to the tab of the bus bar and applying a high voltage to the bus bar and performing a salt water immersion experiment, even if the voltage is increased to 42 V, the electric component to be energized is easily melted. No loss was caused. Specifically, the voltage was applied continuously at 42 V for 8 hours, and then 1
Even after stopping the application for 6 hours and repeating this twice,
No ignition or melting phenomenon occurred, and melting occurred at the third time.
Therefore, it has been confirmed from a normal use condition of an automobile that there is no problem even when a high voltage of 42 V is applied.

[0015]

Embodiments of the present invention will be described below with reference to the drawings. First, as schematically shown in FIG.
An automobile to which the present invention is applied is an engine automobile using an engine E mounted in an engine room (X) for running and power generation. The low-voltage battery 1 and the high-voltage battery are provided in the engine room (X). 2 is installed. The low-voltage battery 1 is a single battery having a rated voltage of 12 V and a maximum voltage of 14 V, which are widely used. The high-voltage battery 2 includes three batteries 2a, 2b, and 2c each having a rated voltage of 12 V similar to the above-described battery.
Are connected in series to have a maximum voltage of 42V. It goes without saying that one battery with a maximum voltage of 42 V may be used.

The low-voltage battery 1 is connected to a low-voltage bus bar 10 in a first case 6 housed in an electric junction box 3 formed of a junction box mounted on the indoor side Y (in some cases in an engine room). And a low voltage (maximum voltage 12 V) is applied. The high-voltage battery 2 is connected to the high-voltage bus bar 11 in the second case 7 housed in the electric junction box 3 to apply a high voltage (maximum voltage 42V).

As shown in FIG. 2, the electric connection box 3 accommodates the first case 6 and the second case 7 in a lower cover 20, and the lower cover 20 has a partition wall 20b standing upright from a bottom wall 20a. And the accommodation chambers 20d and 20e on both sides surrounded by the partition wall 20b and the peripheral wall 20c.
In addition, an electric wire insertion opening 2 is provided at a position facing the bottom wall 20c.
0f and 20g are provided.

One of the accommodation chambers 20d of the lower cover 20
Accommodates a first case 6 in which the low-voltage bus bars 10 and the insulating plates 12 are alternately stacked. The high-voltage bus bar 11 and the insulating plate 13
And a second case 7 in which are alternately stacked.
Thus, the first case 6 and the second case 7 are separated from the partition wall 2.
0b are arranged in parallel on both sides.

The upper ends of the partition wall 20b and the peripheral wall 20c of the lower cover 20 protrude above the first and second cases 6,7. The upper cover 25 is put on the lower cover 20 so as to be locked with the lower cover 20.

A concave portion 20h is provided on the upper end surface of the partition wall 20b of the lower cover 20, and a concave portion 20j is also provided on the upper end surface of the peripheral wall 20c. The rubber packing 33 is loaded into these concave portions 20h and 20j, and the upper portion is locked and connected. The cover 25 is pressed against the bottom surface of the concave portion 25a provided on the inner surface of the cover 25 to achieve waterproofing.

The wire group W1 connected to the low-voltage bus bar 10 housed in the first case 6 is drawn out through a wire insertion opening 20f provided in the lower cover bottom wall 20a. A grommet 35 is attached to the wire group W2 connected to the high-voltage bus bar 11 housed in the second case 7, and the grommet 35 is attached to the wire insertion opening 20g, and the wire group W2 is drawn out.

The electric wire on the power supply side connected to the low-voltage bus bar 10 is connected to the low-voltage battery 1, and the electric wire on the load side is a device such as a sensor or a lamp system which requires a small amount of electric power, as in the prior art. Kind of connected. on the other hand,
The electric wire on the power supply side connected to the high-voltage bus bar 11 is connected to the battery 2 for high voltage, and the electric wire on the load side is connected to an actuator such as a power steering and an engine intake / exhaust device which requires a large amount of electric power. Is operated electrically.

As described above, the low-voltage bus bar 10 and the high-voltage bus bar 11 having different voltages are housed in separate cases, and are blocked by the partition wall 20b protruding from the shared lower cover 20. It is possible to prevent a leak current from being generated between the bus bars 10 and 11 to which different voltages are applied. In addition, the lower case 20 and the upper cover 2 on which the second case 7 containing the high-voltage bus bar 11 is housed.
5, and the electric wire group W2 connected to the second case 7 is also drawn out to the outside via the grommet 35, so that the accommodation room 20e is completely sealed and the occurrence of water intrusion can be reliably prevented. Therefore, no leak current occurs between the high-voltage bus bars due to water inundation.

The above embodiment relates to a general passenger car equipped with a battery rated at 12 V. However, even in a passenger car, a maximum voltage of 28 V is applied to the bus bar, or a truck is applied with a maximum voltage of 28 V to the bus bar. In this case, the bus bar to which a voltage of 28 V is applied is referred to as the low-voltage bus bar, and the bus bar to which a voltage of 42 V is applied is referred to as the high-voltage bus bar. To place.

In the above embodiment, the maximum voltage of 42 V is applied to the high-voltage bus bar 11. However, if the weight of the battery is reduced and the safety is sufficiently ensured, 4
It goes without saying that a high voltage larger than 2 V and up to 200 V may be applied.

[0026]

As is apparent from the above description, according to the present invention, in order to reduce the amount of current, to reduce the thickness of the electric wire and to prevent the wiring harness from being enlarged, the voltage is increased and the low-voltage busbar is reduced. And the high-voltage busbar are housed inside the electrical junction box, the case for housing the busbars to which these different voltages are applied is separated, and
These cases are housed in the common lower cover and upper cover, and are blocked by a partition wall standing upright from the lower cover, so leakage occurs between the low-voltage busbar and the high-voltage busbar and between the high-voltage busbars. Generation of current can be prevented.

Further, since a seal member is interposed between the fitting surfaces of the lower cover and the upper cover, and a group of electric wires drawn from the case accommodating the high-voltage bus bar is drawn out from the lower cover via the grommet, The accommodation room of the high-voltage bus bar is closed, and the occurrence of water intrusion can be prevented, and the occurrence of leak current due to water intrusion between the high-voltage bus bars can be reliably prevented.

[Brief description of the drawings]

FIG. 1 is a schematic diagram of an embodiment of the present invention.

FIG. 2 is a schematic sectional view showing a state where a circuit body is housed in the electric junction box shown in FIG.

FIG. 3 shows a first housing housed inside the electric junction box.
It is sectional drawing which shows the inside of a case and a 2nd case.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Low voltage battery 2 High voltage battery 3 Electric connection box 10 Low voltage bus bar 11 High voltage bus bar 12 Insulating plate 20 Lower cover 20a Bottom wall 20b Partition wall 20f, 20g Electric wire insertion opening 25 Upper cover 30 First case 31 Second case 33 Packing 35 Grommet W1, W2

 ──────────────────────────────────────────────────続 き Continued on front page F term (reference) 4E360 AB12 AB33 AB34 BA08 BC03 BC05 BD03 BD05 EA03 EA18 ED03 ED23 ED27 FA08 GA29 GA33 GB93 GB94 5G361 BA04 BA06 BC01 BC02 5G363 AA01 BA02 CB01 CB08 DC02

Claims (3)

[Claims] A first case accommodating a low-voltage bus bar to which a maximum voltage of 14 V or 28 V is applied;
A second case accommodating a high-voltage bus bar to which a voltage equal to or lower than V is applied; a first case and a second case housed in a lower cover; Set up a wall,
The first case is arranged in one accommodation room surrounded by the partition wall and the peripheral wall, and the second case is arranged and arranged in parallel in the other accommodation room, and at the upper end of the peripheral wall of the lower cover. A high-voltage electrical junction box with an upper cover that covers the upper end of the partition wall with a sealant interposed. 2. An electric wire connected to a bus bar of the first case and the bus bar of the second case disposed in the accommodation chamber, is drawn out to the outside through an electric wire insertion opening provided in a bottom wall of the lower cover, and a high-voltage bus bar. The high-voltage electrical junction box according to claim 1, wherein a grommet is attached to the electric wire on the second case side in which the wire is accommodated, and the grommet is attached to the electric wire insertion opening. 3. The high-voltage electrical junction box according to claim 1, wherein the high voltage is 42V.