JPH1084626A - Power distribution system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To realize reduction in size and weight of an electronic devices and prevent enlargement of the wire harness. SOLUTION: A voltage conversion means 31 is provided in an electrical junction box 28 in the highest up stream side in which a power supply section 27 is connected, the electrical power not converted in the voltage is distributed, from the power supply section 27, to electrical device loads in the electrical junctions boxes 29, 32, 33, 38 and 39 via the electrical junction box 28, and moreover the stable power having the voltage not converted is distributed, from the power supply section 27, to a particular electrical device load which is operated with a noiseless power of a stable voltage (for example, 5V voltage). Therefore, it is no longer required to provide the power supply section to an electronic device and thereby an electronic device can be reduced in size and weight to easily acquire the installation space. Moreover, the degree of freedom of the installation area of particular electronic device load can be expanded on the vehicle and thereby the short length cable can be used for communication and distribution of electrical power.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a power distribution system adapted to, for example, a vehicle and for distributing and supplying power to various electric component loads.

[0002]

2. Description of the Related Art Conventionally, for example, an electric power distribution system for a vehicle is a system for operating various switches to supply electric power to various electric component loads and to drive the electric component loads.
The arrangement of these switches and various electrical component loads on the vehicle is generally determined as shown in FIG. 3, and power supply to the various electrical component loads on the vehicle is performed by connecting a wire harness from a battery or an alternator described later. And distributes the power to the required locations.

FIG. 3 is an image diagram of a vehicle body showing a power supply configuration of a conventional vehicle-mounted power distribution system.

[0004] In FIG. 3, a vehicle body 1 includes, for example, an engine room 2 at a front portion where an engine and the like are mounted, a passenger room 3 including a driver's seat and a passenger seat disposed behind the engine room 2, and a passenger room 3 and a trunk room 4 arranged at the rear of the vehicle.

In the engine room 2, a power supply 7 such as a battery 5 and an alternator 6 for supplying power of a predetermined voltage, and the power supply 7 is connected to the power supply 7 via a wire harness. An electric connection box 8 which is a joint box (J / B) for distributing the power, and various loads such as lamps such as a head lamp and a tail / clearance lamp are provided.

The passenger compartment 3 is a joint box (J / B) that is connected to the electric connection box 8 via a wire harness, and further distributes the electric power supplied from the electric connection box 8 to various loads. An electric connection box 9, an electric connection box 10 connected to the electric connection box 9 via a wire harness, illumination of meters as various loads, illumination of audio, various switches that can be operated, and the like are provided. ing. Further, from the electric connection box 10, the engine room 2 and the passenger compartment 3
A wire harness extends inside the wire harness, and branches off from the wire harness to be connected to various loads. In addition, these electric connection boxes 9 and 10
Various systems 11 having a central processing unit (CPU) as an electrical component load are branched from the wire harness between them and are branched.

Further, the passenger compartment 3 and the trunk room 4
, A wire harness connected to an electric connection box 9 in the passenger compartment 3 extends, and lamps such as a backlight as various loads and various systems connected in a branched manner from the wire harness. 11 and the like are provided.

The battery 5 is chargeable and dischargeable, and is a power supply source for an engine start motor when the engine is stopped such as when the engine is started. In addition, the battery 5 always supplies a voltage of 12 V (voltage 12 V is a normal small vehicle and a voltage of 24 V for a normal large vehicle) with respect to various electric component loads scattered around the vehicle even when the vehicle is stopped or not used. ). For example, a load of various electrical components such as a control unit (ECU), a radio, and a clock needs to always operate its memory function normally, so that even when the vehicle is stopped or not used, Power is always supplied via a protection circuit such as a fuse or a fusible link (F / L).

[0009] The alternator 6 is a power supply source for generating power by rotation of the engine during operation of the engine.
When the vehicle is in use, the alternator 6 supplies electric power of voltage 12V (voltage 12V is a normal small vehicle and voltage 24V for a normal large vehicle) to various electric component loads scattered around the vehicle. Supplying. further,
In order to respond to the power supply by the power generation of the alternator 6, each electric component such as an air conditioner or a headlight having a large power consumption as various loads is provided.
The number of revolutions of the engine is changed according to the frequency of use and the amount of power consumption. As described above, the alternator 6 is controlled in power generation by the engine speed. Further, the power supplied from the alternator 6 has noise on the power due to the coil in the alternator 6 and is a considerably unstable power source.

Further, C as a load of various electric components of the vehicle is
Among various systems 11 such as a control unit (ECU) having a PU, an engine control computer, an ABS control computer, and an electronic device such as an audio device each having a precision device have a low voltage (normally 5 V).
It is necessary to operate the power supply 12 for converting the power supplied from the battery 5 and the alternator 6 of the power supply 7 of the vehicle into the required stabilized voltage level. We have individually.

Furthermore, these electric connection boxes 8, 9, 10
Are provided with a current limiting circuit as a protection circuit such as a fuse or a fusible link (F / L), and a switching circuit such as a relay circuit. Electrical components with a large drive current, such as air conditioners, are not directly operated by operation switches, but are made to conduct through relay contacts or power semiconductor switches having a large current capacity.

[0012]

For example, in vehicles such as passenger cars, various engine control computers, ABS control computers, audio devices, and the like are provided depending on market needs such as improvement of driving comfort, system multi-equipment and upgrading. A control unit (E
CU) and the like, and the number of electronic devices mounted on the vehicle is increasing. However, contrary to the market needs such as improved driving comfort, multi-system and higher-grade systems, in-vehicle electrical components have been reduced in size and weight in order to consider the global environment and to reduce fuel consumption. We are also considering the conversion.

With the increase in electronic devices as on-vehicle electrical components due to market needs such as improvement in driving comfort, the number of power supply units built in those electronic devices has also increased, and their size and weight have been reduced. Hindered.

Further, with the increase of such electronic devices, it has become difficult to secure a space for installing electronic devices in a vehicle, and an operation switch and an electronic component load controlled by the operation switch as an electronic component load. The equipment can be installed only in a place away from each other, and the wires required for communication and power supply between them become longer, causing the wire harness to enlarge (outer diameter, weight increase, etc.) and increase costs. I have. The problem with the enlargement of the wire harness is that it is difficult to secure the installation space inside the vehicle and to assemble it into the vehicle.Moreover, the wire harness exterior and the wire coating are damaged due to pinching, bending and abrasion. There is a possibility that a short circuit may occur.

An object of the present invention is to solve the above-mentioned conventional problems, and an object of the present invention is to provide a power distribution system capable of reducing the size and weight of an electronic device and preventing an enlargement of a wire harness.

[0016]

The power distribution system according to the present invention is provided with a plurality of power distribution units for distributing power to a plurality of various loads via respective distribution power lines branched from the power lines. In a power distribution system in which a power supply unit is connected to at least one of the power distribution units via a power line, and the plurality of power distribution units are each supplied with power via a power line, the power supply unit is connected via a power line. The connected power distribution unit is provided with a voltage conversion unit that converts a voltage from the power supply unit to a predetermined voltage and removes noise, and a power line from the voltage conversion unit and a power line from the power supply unit. The plurality of power distribution units are respectively supplied with power, and are respectively supplied to a plurality of various loads via distribution power lines branched from the respective power lines. And it is characterized in that it is force distributor.

According to this configuration, a specific electric component load that cannot be used with a power supply voltage from a power supply unit and requires clean stable power without noise, such as an electronic device such as an engine control computer, an ABS control computer, and an audio device. Conventionally, each had a dedicated voltage conversion unit, but the voltage conversion unit provided in the most upstream power distribution unit converts the stabilized power, which has been converted to a predetermined voltage and noise-cut to the predetermined voltage, to the downstream side. Since the power is supplied to the specific electrical component load via the power distribution unit, the voltage conversion units that the specific electrical component load has conventionally had can be integrated and arranged. In addition, the need for a voltage conversion unit is eliminated, so that the fuel consumption of the vehicle can be reduced by reducing the size and weight, and the space is advantageous. For this reason, it is possible to secure a space for the installation place, and the operation switch and the electronic device as the electric component load controlled by the operation switch can be installed only in places apart from each other, and communication and power supply between them can be performed. The conventional problem that a required electric wire becomes long is solved, that is, an electric wire at a crossing portion of the wire harness is omitted, and it is possible to suppress the enlargement of the wire harness. By suppressing the enlargement of the wire harness, it is possible to secure more installation space in the vehicle and to assemble it to the vehicle, and to short-circuit the wire harness exterior or the wire coating due to pinching, bending and abrasion. Are also suppressed.

Preferably, the power supply path between the voltage conversion means and the specific various loads in the power distribution system of the present invention is subjected to noise proof processing.

With this configuration, if the power supply path on the downstream side of the voltage conversion means is subjected to noise-resistant processing such as a shield, the supply power is not affected by noise due to the adverse effects from the surroundings. The power can be supplied to a specific electrical component load by maintaining the power at a predetermined stable voltage, which is converted to a predetermined voltage by the means and noise is removed.

Further, preferably, the power line from the voltage conversion means and the power line from the power supply unit in the power distribution system of the present invention are integrally formed by a reinforced electric wire.

According to this configuration, since the power lines from the power supply unit and the voltage conversion means are integrated with the reinforced electric wires, short-circuiting due to pinch, bending, abrasion, etc. of the wire harness or breakage of the electric wire coating can be prevented. It will be further suppressed.

Further, preferably, in a power distribution system constituted by a vehicle-mounted wire harness, the power distribution unit is constituted by an electric connection box, and the electric connection box is disposed at a position near a load on the vehicle. Therefore, each electric connection box is connected to various loads.

According to this configuration, the electric junction box is disposed in the vicinity of the load where the loads on the vehicle are concentrated. Therefore, the main junction can be provided without arranging many power supply lines and ground lines for each load. Electric power can be distributed to and supplied to various electric component loads via the electric connection box via the electric power line, and the wiring harness can be reduced in size, and the enlargement of the wiring harness can be prevented. In addition, if the present invention is applied to the form of the on-vehicle system, not only the load of the electric component operable with the power from the power supply unit but also a voltage different from the voltage from the power supply unit (for example, low voltage) Similarly, for a specific electrical component load that needs to operate with clean and stable power without noise, a power line composed of many power supply lines and a ground line for each specific electrical component load as described above. Power can be supplied from the main power line via the electric connection box without routing, and the wiring harness can be reduced in size, thereby preventing the wiring harness from being enlarged. Also,
If the present invention is applied to the form of the in-vehicle system, a voltage conversion unit is not required for each specific electrical component load that requires noiseless and stable power, and the size and weight can be reduced. Therefore, it is possible to easily cope with an increase in the load of a specific electrical component due to market needs such as the realization of the vehicle, such as securing a space for an installation place on a vehicle.

[0024]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an embodiment of a power distribution system according to the present invention will be described with reference to the drawings.

FIG. 1 is a vehicle image diagram showing a schematic power supply configuration of a vehicle-mounted power distribution system according to an embodiment of the present invention.

In FIG. 1 and FIG. 2, a vehicle body 21 has an engine room 2 in a front portion where an engine and the like are mounted.
2, a passenger compartment 23 including a driver's seat and a passenger seat disposed behind the engine room 22, and a trunk room 24 disposed behind the passenger compartment 23.

In the engine room 22, a power supply 27 such as a battery 25 and an alternator 26 for supplying electric power of a predetermined voltage (voltage of a normal small vehicle is 12V, voltage of a normal large vehicle is 24V, and 12V in this embodiment). Electric connection box 2 which is a joint box (J / B)
8, 29, etc. are provided. The battery 25 and alternator 26 of the power supply unit 27 and the electric connection box 28
Are connected by a main line (power line) 30 composed of a wire harness.
A main line (power line) 30 composed of a wire harness is also connected between 8, 29. Further, these electric connection boxes 28 and 29 are respectively disposed at positions in front of both ends in the vehicle width direction in the vicinity of various load electric components such as left and right lamps, and the electric power supplied from the power supply unit 27 is provided. Are distributed to various electric component loads such as a headlamp and a tail / clearance lamp via a branch line (distributed power line) 30a composed of a power supply line and a ground line.

A voltage from the battery 25 and the alternator 26 of the power supply unit 27 is converted into a predetermined constant voltage (5 V in this embodiment) in the electric connection box 28 closest to the power supply unit 27 on the most upstream side. Voltage converter 31 composed of a voltage converter and a noise filter for removing noise
Are arranged. This voltage conversion means 31
The power supply from 7 requires clean stabilized power that is unusable, has no voltage fluctuations, and has no noise. In particular, electronic equipment loads having a CPU, such as engine control computers and ABS control computers having precision equipment, and electronics such as audio systems. A noiseless stabilized voltage can be supplied to a control unit (ECU) 31 which is a specific various load system such as a device.

Further, in the passenger compartment 23, electric connection boxes 32 and 33, which are joint boxes (J / B), are provided in front of both ends in the vehicle body width direction at positions near various electric components. The electric connection box 32 is connected to the electric connection boxes 28 and 33 via the trunk line 30, and the electric connection box 33 is connected to the electric connection box 29 via the main line 30. The trunk 30 between the electric connection boxes 28 and 32 and between the electric connection boxes 32 and 33 is, as shown in FIG.
A reinforcement (armor) layer 35 is provided inside the covering layer 34, a short-circuit detection layer 37 is provided inside the reinforcement (armor) layer 35 via a sheath 36, and further, inside the short-circuit detection layer 37. Various electric wires are provided. These various electric wires are connected to the output terminal of the voltage conversion means 31, supplied with a noiseless stabilized voltage, and subjected to noise-resistant processing by a shield member 38. And a 12V power supply line 40 connected to the output terminal of the alternator 26, for example, a multiplex signal line 4 composed of a twisted line for a signal from an operation switch or the like.
1 and the drain line 42 and the like. Also, the power supply unit 2
7 and the electric connection box 28, and the electric connection boxes 28 and 29
Between the trunk line 30 between the shield member 38 and the ECU 5
The configuration is the same as that of the trunk line 30 between the electric connection boxes 28 and 32 and between the electric connection boxes 32 and 33, except that the V power supply line 39 is not included. 5 for these ECUs
Each of the V power supply line 39 and the 12 V power supply line 40 is composed of a single power supply line and a ground line, respectively. The multiplex signal line 41 is also composed of a total of two signal lines, one signal line and a ground line. Further, the short-circuit detection layer 37 is always applied with a constant voltage with a limited current, and detects a short-circuit by detecting a change in the constant voltage. Further, a power supply path between the voltage conversion means 31 and specific various loads, that is, this E
The power supply path by the CU 5V power supply line 39 includes, in addition to the shield member 38 and the ECU 5V power supply line 39, electric wires and connectors (shielded electric wires,
Shielded connectors) are used, and high-quality power is supplied. As a result, the supply power is not affected by noise due to the adverse influence from the surroundings, and the voltage is converted to a predetermined voltage by the voltage conversion means 31, and the stable stable power from which the noise is removed is maintained.

Each of the electric connection boxes 32 and 33 is connected to the electric connection box 2 via the 12 V power supply line 40 of the main line 30.
The power that can be supplied from the power supply units 8 and 29 is further distributed to various electrical component loads via a branch line 30a composed of a power supply line and a ground line, and various operation switches and various electrical components are connected via the multiplex signal line 41 of the trunk line 30. Connected to load. Further, the electric connection box 32 distributes noiseless stabilized power supplied from the voltage conversion means 31 of the electric connection box 28 via the 5V power supply line 39 for ECU of the main line 30 to the control unit (ECU) 43. Supply. Further, the electric connection box 33 distributes noiseless stabilized power supplied from the electric connection box 32 via the 5V power supply line 39 for ECU of the trunk line 30 to distribute each control unit (E
CU) 43.

Further, in the trunk room 24, electric connection boxes 44 and 45, which are joint boxes (J / B), are disposed in front of both ends in the vehicle width direction at positions near loads of various electric components. The electric connection box 44 is connected to the electric connection boxes 32 and 45 via the trunk line 30 respectively.
The electric connection box 45 is also connected to the electric connection box 33 via the trunk line 30. These electric junction boxes 44 and 45 respectively supply 12 volts of electric power that can be supplied from the electric junction boxes 32 and 33.
The power is distributed from the V power supply line 40 to loads of various electric components such as a backlight via a branch line 30a composed of a power supply line and a ground line. The electric connection box 44 is connected to the trunk line 30.
Electrical connection boxes 32, 4 via the 5V power supply line 39 for the ECU.
5 and supplies the stabilized power to each control unit (ECU) 43 and the like. Further, the electric connection box 45 distributes stabilized electric power that can be supplied from the electric connection boxes 33 and 44 via the 5V power supply line 39 for the ECU of the trunk line 30 and supplies it to each control unit (ECU) 43 and the like. The configuration of the trunk 30 between the electrical junction boxes 32 and 44, between the electrical junction boxes 33 and 45, and between the electrical junction boxes 44 and 45 is different from the configuration of the trunk 30 between the electrical junction boxes 28 and 32. Similarly, it has a 12V power supply line 40, a shield member 38 and a 5V power supply line 39 for ECU. In other words, the part where the shield member 38 and the 5V power supply line 39 for the ECU are installed is a control unit (EC
U) It is sufficient only in the main line 30 to the electrical junction box to which a specific electrical component load such as 43 is connected, and is connected to various electrical component loads operating at a normal power of 12 V from the power supply unit 27. It is not necessary to have the shield member 38 and the 5V power supply line 39 for ECU in the trunk line 30 leading to the connection box.

Further, the electric connection boxes 28, 29, 32, as power distribution units for distributing power to a plurality of various electric component loads,
Reference numerals 33, 44, and 45 are respectively disposed at the optimal parts of the vehicle where the load is concentrated. The most upstream electric connection box 28 is directly supplied with power from the power supply unit 27, and the other downstream electric connection boxes. 32, 33, 44, and 45 are respectively connected to the battery 25 of the power supply unit 27 and the 12 V power of the alternator 26 from the most upstream electric connection box 28 via at least two main lines 30, and the noiseless 5V stabilized power can be supplied via independent power supply paths. Further, transmission of control signals from various electric component loads and operation switches and transmission of control signals to other electric connection boxes are performed by the electric connection box 28,
29, 32, 33, 44, and 45 are performed via the multiplex communication line 41, respectively.

Thus, the joint box (J /
B) electrical junction boxes 28, 29, 32, 33, 44,
45 are installed in the vicinity of the electrical component loads, respectively, and the power supply to the individual electrical component loads is all distributed from the nearby electrical junction box and supplied.

The operation of the above configuration will be described below. First, when a vehicle driven by an engine is used, an electric connection box 28, which is a joint box (J / B), is supplied with electric power from an alternator 26 of a power supply unit 27, and is supplied from the electric connection box 28 via a main line 30. For example, as an example of a power supply system, a joint box (J /
B), an electric power is supplied to the electric connection box 32 and the electric connection box 33, and the electric power supplied to the electric connection box 33 is supplied to the electric connection boxes 29 and 45, and the electric power is supplied from the electric connection box 45. Electric power is supplied to the electric connection box 44. These electric connection boxes 28, 29, 32, 33, 44, 45
Respectively, for the electrical component load usable with the power supply voltage from the power supply unit 27, the 12V power supply line 4
0 is distributed and supplied to various electrical component loads via the power supply line at 0 and the power supply line of the branch line 30a, and the power distributed and supplied for each electrical component load drives the various electrical component loads. After that, they are integrated by the earth line of the trunk line 30 and flow out through the distribution earth line of the branch line 30a.

At this time, each control unit (ECU) as a load of a specific electric component such as an electronic device which cannot be used with the power supply voltage from the power supply section 27, requires no voltage fluctuation, and requires clean stable power without noise. ) 43 etc., in the most upstream electrical junction box 28, the voltage conversion means 31 converts the power supply voltage from the power supply unit 27 to a stabilized predetermined power supply voltage and supplies high-quality power with reduced noise. 5V power supply line 39 for ECU, which is shielded by a shield member 38 and subjected to noise resistance processing, and further controlled via noise-resistant wires and connectors (shielded wires, shield connectors, etc.). Power is distributed to each unit (ECU) 43.

Here, if high-quality noise-free power is supplied to all electrical component loads on the vehicle, one set of power lines in the trunk line 30 may be used. In order to obtain the power that is equivalent to the amount of power consumed by a constant voltage and noise-less power (or power that addresses the problem of the vehicle power supply, for example, reverse connection of battery terminals, etc.), a fairly large constant-voltage converter is required. Will be needed. For this reason, a high-quality noise-free ECU is provided so that noise-free power is supplied at a constant voltage for the required power consumption.
There are two sets of power lines for transmitting 5 V power and 12 V power from the power supply unit 27.

Accordingly, the voltage conversion means 31 is provided in the most upstream electric connection box 28 to which the power supply unit 27 is connected.
Through this electric connection box 28, each electric connection box 29, 32,
Each of the electric connection boxes 33 and 45 and the electric connection box 44 are distributed to and supplied to an electric component load operable with 12 V power which is not converted from the power supply unit 27 and the voltage is converted from the power supply unit 27 to a stable state. The regulated power is distributed and supplied to a specific electrical component load such as an electronic device that can operate with clean power without noise at a stabilized voltage (5 V in this embodiment) different from the voltage from the alternator 26. That is, the power supply unit 27 supplies high-quality power with a predetermined voltage and no noise.
Voltage and noiseless near the location, and its dedicated lines are installed in the trunk line 30 and in the electrical junction box, and high-quality power is distributed from each electrical junction box to a specific electrical component load such as electronic equipment. Supply. As described above, in order to integrate high-quality power from one voltage conversion means 31 in the electric connection box 28 on the most upstream side through the wire harness and supply it to the downstream side, the power supply for each electronic device is different from the conventional one. There is no need to provide a unit. For this reason, these electronic devices can be reduced in size and weight, which leads to lower fuel consumption of the vehicle. In addition, by making such an electronic device smaller, it is easy to secure a space for an installation place in the vehicle. Furthermore, by not providing a power supply unit for each electronic device, the cost of various electronic devices can be reduced, and the fuel consumption due to the increase of various electronic devices can be maintained even in the future with further increase of various electronic devices. Deterioration and cost increase can be easily suppressed.

Further, since various electronic devices can be reduced in size and weight, the degree of freedom in installation locations on the vehicle is expanded, and the control unit (ECU) 43 or the like can be operated at an optimal location with clean power without noise. A specific electrical component load such as an electronic device that can be installed can be installed, and the operation switch and the electronic device as the electrical component load controlled by the operation switch can be installed only in a place apart from each other, and communication between them can be performed. The conventional problem that the electric wire required for power supply becomes long is also solved, and the enlargement of the wire harness can be suppressed. By suppressing the enlargement of this wire harness,
Further installation space in the vehicle can be ensured and assembly into the vehicle can be facilitated, and short-circuiting due to breakage of the wire harness exterior or electric wire coating due to pinching, bending and abrasion can be prevented.

Further, the power supply unit 27 and the voltage conversion means 3
Since the trunk line 30 from 1 is integrally formed with a reinforced electric wire such as an armored electric wire, a short circuit due to pinch, bending, abrasion, etc. of the wire harness exterior or breakage of the electric wire coating can be further prevented.

In the embodiment of the present invention, the voltage conversion means 31 is provided in the power distribution section 28 on the most upstream side to perform voltage conversion and noise cut. However, in order to remove noise generated from the computer itself, the computer is used. The noise removing means may be provided in the computer itself. In this case, since the voltage converting means 31 of the present invention is provided, the noise removing means provided in the computer itself can be configured smaller than usual. Further, for example, when one kind of voltage such as 5 V is used in a computer, only the voltage converting means 31 of the present invention is sufficient, but there is a load using a special voltage level which cannot be converted by the voltage converting means 31 of the present invention. In such a case,
It is necessary to provide the load itself with a voltage converter. Also in this case, since the voltage conversion unit 31 of the present invention is provided, the voltage conversion unit provided in the computer itself does not require noise cut or the like, and can be configured smaller than usual.

In the embodiment of the present invention, 12 V is set to 5
Although the voltage converting means 31 for converting the voltage to V and cutting the noise is provided, the voltage converting means is not limited to this, and may be a voltage converting means for converting a predetermined voltage to a constant voltage lower than that and cutting the noise. Needless to say.

[0042]

As described above, according to the present invention, since the voltage conversion means is provided in the most upstream electric connection box to which the power supply unit is connected, the power supply unit which a specific electric component load individually has is provided. It is possible to unify and arrange, and it is possible to reduce the size and weight of a specific electric component load, and it is possible to easily reduce the fuel consumption of the vehicle and secure the space for the installation location. In addition, by securing the space for this installation location, the degree of freedom in installing the specific electrical component load on the vehicle is expanded, the wires required for communication and power supply are not lengthened, and the enlargement of the wire harness is suppressed. Can be.

Further, if a noise-resistant process such as a shield is applied to a power supply path downstream of the voltage conversion means, stable power can be supplied to a specific electrical component load without being affected by surroundings. it can.

Further, since the power lines from the power supply unit and the voltage conversion means are integrally formed by the reinforced electric wires, short-circuits due to pinch, bending and abrasion, etc. of the wire harness exterior and breakage of the electric wire coating are further prevented. be able to.

Further, since the electric connection box is disposed in the vicinity of the load where the loads on the vehicle are concentrated, the main power line can be connected without arranging many power supply lines and earth lines for each load. Electric power can be distributed and supplied to various electric component loads via the electric connection box, and the wire harness can be saved, and the wire harness can be prevented from being enlarged. In addition, if the present invention is applied to the form of the on-vehicle system, a large number of electric loads for each specific electric component load can be applied to the specific electric component load requiring noiseless stabilized power in the same manner as described above. Power can be supplied via the electrical junction box with the main power line without laying the power line consisting of the power supply line and the ground line, wire saving of the wire harness can be realized, and enlargement of the wire harness can be prevented.
In addition, a voltage conversion unit is not required for each specific electric component load, thereby achieving a reduction in size and weight, and can easily cope with an increase in a specific electric component load, such as securing a space for an installation place on a vehicle. be able to.

[Brief description of the drawings]

FIG. 1 is a vehicle image diagram showing a power supply configuration of a vehicle-mounted power distribution system according to an embodiment of the present invention.

FIG. 2 shows a trunk line 3 between the electric connection boxes 28 and 32 in FIG.
It is an enlarged view which shows the cross-sectional structure of No. 0.

FIG. 3 is a vehicle body image diagram showing a power supply configuration of a conventional vehicle-mounted power distribution system.

[Explanation of symbols]

 Reference Signs List 25 battery 26 alternator 27 power supply unit 28, 29, 32, 33, 44, 45 electric connection box 30 main line (power line) 30a branch line (distributed power line) 31 voltage conversion means 35 reinforcing (armor) layer 38 shield member 39 5V power supply for ECU Line 40 12V power line 41 Multiple signal line 43 Control unit (ECU)

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Hideaki Toyama 1-7-10 Kikuzumi, Minami-ku, Nagoya-shi, Aichi Inside Harness Research Institute, Inc. (72) Inventor Motonori Kido 1 Kikuzumi, Minami-ku, Nagoya-shi, Aichi No.7-10, Harness Research Institute, Inc.

Claims (4)

[Claims] 1. A power distribution unit for distributing power to a plurality of loads via a distribution power line branched from a power line. A power supply unit is provided in at least one of the plurality of power distribution units. In a power distribution system connected via a power line and the plurality of power distribution units are each supplied with power via a power line, the power distribution unit includes a power supply unit connected to the power distribution unit via the power line. Voltage converting means for converting the voltage from the power supply into a predetermined voltage and taking noise is provided, and the plurality of power distributing sections respectively provide power via a power line from the voltage converting section and a power line from the power supply section. The power distribution system is characterized in that the power is distributed to each of a plurality of loads via the distributed power lines which are supplied and branched from the respective power lines. Tem. 2. A power distribution system according to claim 1, wherein a power supply path between said voltage conversion means and specific various loads is subjected to noise proof processing. 3. A power line from the voltage conversion means, and
The power distribution system according to claim 1, wherein the power line from the power supply unit is configured integrally with a reinforced electric wire. 4. An electric power distribution system comprising an in-vehicle wire harness, wherein the electric power distribution unit is constituted by an electric connection box, and the electric connection box is disposed at a position near a load on a vehicle. 2. The power distribution system according to claim 1, wherein the power distribution system is connected so as to distribute the load to various loads for each connection box.