JP2016013754A - Electrical equipment connection system for vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the number of kinds of wiring harness by simplifying a wiring harness configuration even in a case where option equipment is connected, and to realize proper protection against an excessive load current of system by a protection device arranged in a relatively small space.SOLUTION: There are provided a standard system power source distribution box 20S which distributes a power source from an on-vehicle main power source 10 and supplies power to each of a plurality of power source lines 31a, 31b of a standard system sub-harness 31 of a wire harness 30, and an expansion system power source distribution box 20E which distributes a power source from the on-vehicle main power source 10 and supplies power to each of a plurality of trunk lines 32a-32f of an expansion system sub-harness 32 of the wire harness 30.

Description

  The present invention connects a plurality of electrical devices each including at least one of a load, a switch, and a sensor to an electric system of a vehicle via a predetermined wire harness, and at least from the vehicle side to each electrical device The present invention relates to a vehicular electrical equipment connection system for supplying power.

  Various electric devices such as various lamps and motors, switch devices for operating these, and sensors are mounted on the vehicle in a dispersed state at various locations. These various electrical devices are connected to a wire harness for supplying power supplied from a battery or the like, a control signal for controlling these electrical devices, and the like. This wire harness generally includes a plurality of electric wires and connectors. The electric wire includes a conductive core wire and an insulating covering portion that covers the core wire. The connector includes a terminal fitting attached to the end of the electric wire and connected to the wire, and a connector housing made of an insulating resin that accommodates the terminal fitting.

  Further, in recent years, as a communication system for controlling a plurality of vehicle electrical components mounted on a vehicle, a plurality of electronic control units that control each vehicle electrical component are connected by a common multiplex communication line, and the multiplex communication line is connected. A vehicle network system is used in which multiplexed signals are transmitted and received and the operation of each vehicle electrical component is controlled based on the signals (see, for example, Patent Document 1).

  By the way, as for the wire harness routed in a vehicle, for example, a plurality of circuit-specific sub-harnesses sub-divided for each system circuit are combined to form a whole wire harness. As system circuits, for example, standard circuits that constitute essential electrical equipment for automobiles such as headlamps and wipers, and electrical equipment that is selected according to the vehicle type, grade, etc. such as security and rear fog lights, etc. There is an optional circuit to do. And when manufacturing such a wire harness for motor vehicles, it determines so that the whole wire harness may become suitable, considering the arrangement | positioning of a connector, a terminal, the kind of electric wire, etc. FIG.

JP 2004-268630 A

  As described above, the wire harness routed in the vehicle is configured by combining various sub-harnesses according to various electrical devices mounted on the vehicle. Therefore, the number of wires constituting the entire wire harness increases and the structure becomes complicated.

  In addition, if the vehicle type, grade, destination, etc. in the vehicle change, there will be differences in the presence / absence of various optional electrical equipment, locations of installation, types of optional electrical equipment, etc. Must be changed appropriately. In other words, the option to actually install the presence / absence of each sub-harness, the position where each sub-harness is arranged, the length of the electric wires that make up each sub-harness, the thickness of the electric wires, the type of connector connected to the end of the electric wires, etc. It is necessary to change according to the electrical equipment.

  Therefore, when manufacturing various vehicles having different vehicle types, grades, destinations, etc., various types (configurations) of wire harnesses corresponding to differences in the vehicle types, grades, destinations, etc. are manufactured in advance. Assign an appropriate part number for each type of harness. And when mounting a wire harness in a vehicle, the wire harness of the corresponding product number is selected according to the vehicle type, grade, destination, etc., and assembled to the vehicle body.

  However, if the optional electrical equipment mounted on the vehicle changes depending on the vehicle type, grade, destination, etc., the configuration of the required wire harness changes, so the number of wire harness types (part number) increases. . If the number of the wire harness to be assembled increases, the assembly work in the wire harness assembly line becomes complicated, and the efficiency of the wire harness assembly work decreases. For this reason, there exists a problem that the mass productivity of a wire harness falls and the cost of each component and wire harness itself rises.

  On the other hand, in order to reduce the number of types of wire harnesses, it may be assumed that sub-harnesses corresponding to optional electrical equipment are incorporated in advance in all wire harnesses having a standard configuration. However, if optional electrical equipment is not installed in an actual vehicle, the optional sub-harness added to the standard wire harness is unused, that is, it is in a “discarded” state, resulting in increased waste. End up. This also increases the cost of the wire harness.

  In addition, since it is necessary to supply power to each electric device under control from a battery or the like as a main power source of the vehicle, a connection box or a power distribution box may be disposed between the main power source and the wire harness. Many. In such a connection box and a power distribution box, the power to be supplied is distributed to a plurality of systems according to the number of electrical equipments connected under the wire harness. For each output system, when the load current becomes excessive, the fuse is cut to cut off the power supply and protect each circuit.

  Therefore, if the optional electrical equipment mounted on the vehicle changes depending on the vehicle type, grade, destination, etc., not only the configuration of the wire harness but also the configuration inside the power distribution box must be changed. In particular, when connection of a large number of optional electrical devices is permitted, a space for arranging a large number of fuses must be secured inside the power distribution box so that the currents of the large number of optional electrical devices can be individually managed. Therefore, when the optional electrical equipment is not connected to an actual vehicle, the space secured in the power distribution box is wasted, and the power distribution box occupies more space than necessary.

  The present invention has been made in view of the circumstances described above, and its purpose is to simplify the configuration of the wire harness and reduce the number of types of wire harness even when connecting optional electrical equipment. It is an object of the present invention to provide a vehicular electrical equipment connection system capable of appropriately protecting against an excessive load current of each system by a protection device arranged in a relatively small space.

In order to achieve the above-described object, the vehicle electrical equipment connection system according to the present invention is characterized by the following (1) to (5).
(1) A vehicular electrical equipment connection system for connecting a plurality of electrical equipment to an electrical system of a vehicle via a wire harness and supplying power to each electrical equipment from at least the vehicle side,
A standard power distribution unit that distributes power from a power source on the vehicle and supplies power to each of a plurality of trunk lines of the standard system of the wire harness;
An extended power distribution unit that distributes power from the power supply and supplies power to each of a plurality of trunk lines of the extended system of the wire harness;
A vehicle electrical equipment connection system comprising:
(2) The extension system power distribution unit is provided with a switching unit for each of a plurality of trunk lines of the extension system of the wire harness,
A plurality of expansion system electrical devices are connected to the switching unit via the trunk line.
The vehicle electrical equipment connection system according to (1) above, wherein
(3) The extension system electrical equipment is wired by the power supply line of the extension system electrical equipment being retrofitted to the main line.
The vehicle electrical equipment connection system according to (2) above, wherein
(4) As a plurality of expansion system electrical devices, the first expansion system electrical device and the second expansion system electrical device,
The first expansion system electrical equipment is directly connected to the trunk line,
The vehicle electrical equipment according to (2) above, wherein the second extension system electrical equipment is wiredly connected by retrofitting a power line of the second extension system electrical equipment to the main line. Equipment connection system.
(5) An electronic fuse that is disposed in the expansion system power distribution unit and that blocks a corresponding current when the magnitude of a current flowing through each of the plurality of trunk lines of the expansion system of the wire harness exceeds a cutoff threshold;
A storage unit for storing data on a cutoff threshold used by the electronic fuse;
The vehicle electrical equipment connection system according to any one of the above (1) to (4), characterized by comprising:

According to the vehicular electrical equipment connection system having the configuration (1), even when a large number of optional electrical equipment are connected, the number of wires constituting the wire harness can be reduced.
According to the vehicle electrical equipment connection system configured as described in (2) above, it is allowed to connect a plurality of extension system electrical equipment to a single trunk line. The number of power supply lines constituting the can be reduced. As a result, when different types of wire harnesses are prepared in advance for various vehicle types, various grades, various destinations, etc., the types and product numbers of wire harnesses to be prepared are reduced, and the manufacturing process is simplified. Or cost reduction.
According to the vehicular electrical equipment connection system having the configuration of (3) or (4) above, it is easy to retrofit various functions, so that the added value of the vehicle is improved.
According to the vehicle electrical equipment connection system configured as described in (5) above, since the cutoff threshold of the electronic fuse is variable, a change in the number of electrical equipment connected to the extended system power distribution unit or a change in specifications However, it is possible to appropriately change the cutoff threshold without replacing parts or the like.

  According to the vehicle electrical equipment connection system of the present invention, since a plurality of electrical equipment can be commonly connected to the common power line, the configuration of the wire harness can be simplified even when a large number of optional electrical equipment is connected. The number of types of wire harnesses can be reduced. In addition, by adopting the common power line and the electronic fuse, it is possible to appropriately protect against overcurrent and to significantly reduce the physical space to be secured for the extended power distribution unit.

  The present invention has been briefly described above. Further, the details of the present invention will be further clarified by reading through a mode for carrying out the invention described below (hereinafter referred to as “embodiment”) with reference to the accompanying drawings. .

FIG. 1 is a block diagram illustrating a configuration example of a vehicle electrical device connection system according to an embodiment. FIG. 2 is a block diagram showing the internal configuration of the extended system power distribution box. FIG. 3 is a schematic diagram illustrating a configuration example of an overcurrent threshold table. FIG. 4 is a flowchart illustrating an operation example of the diagnosis mode.

  Specific embodiments of the vehicle electrical equipment connection system of the present invention will be described below with reference to the drawings.

<Description of configuration>
<Overall configuration>
The structural example of the electrical equipment connection system for vehicles in this embodiment is shown in FIG. In practice, an enormous number of electrical devices are mounted on one vehicle, but in order to facilitate understanding, only the configuration of the main part is shown in FIG. Further, in FIG. 1, illustration of a control system and a communication line for controlling each electrical equipment is also omitted.

  In the configuration shown in FIG. 1, it is assumed that standard electrical equipments 41 and 42 are mounted on a vehicle as standard electrical equipment, and various extended electrical equipments 51 to 56 can be optionally mounted on the vehicle. doing.

  As specific examples of the standard electrical equipments 41 and 42, electrical equipment that is standardly installed in all vehicles, such as a headlight, a wiper, a tail lamp, and a blinker lamp, can be considered. The expansion system electrical devices 51 to 56 are electrical devices that are selectively mounted according to the difference in vehicle type, grade, destination (domestic / overseas, etc.), and representative examples include fog lamps, Power windows, electric seats, security devices, etc. can be considered.

  The various extension system electrical devices 51 to 56 are grouped in advance according to the difference in the mounting location and the division on the system. In the example shown in FIG. 1, an expansion system electrical device 51 belonging to the engine system, an expansion system electrical device 52 disposed in the vicinity of the instrument panel, an expansion system electrical device 53 disposed in the vicinity of the roof of the vehicle body, and the vehicle It is assumed that there is an expansion system electrical device 54 and other expansion system electrical devices 55 and 56 arranged near the door.

  Although not shown, each of the standard electrical devices 41 and 42 and the extended electrical devices 51 to 56 incorporates at least one of a load, a switch, a sensor, and the like. Further, a driver for controlling energization of the load, and a signal processing circuit for processing signals output from the switches and sensors are also provided.

  Specific examples of the load include a lamp, an electric motor, and a relay. This can be driven by energizing the load. A driver that controls a load incorporates a switching element such as a transistor, for example, and can perform on / off of energization of the load and duty control of energization according to a control signal.

  In the configuration shown in FIG. 1, standard electrical equipments 41 and 42 are connected to the ends of power supply lines 31 a and 31 b of a standard sub-harness 31 that is a part of the wire harness 30, respectively. The standard system sub harness 31 is connected under the standard system power distribution box 20S.

  The input side of the standard system power distribution box 20 </ b> S is connected to the vehicle main power supply 10 via the main fuse MF <b> 1 and the power supply line 11. The on-vehicle main power supply 10 includes a battery, a generator (alternator), and the like mounted on the vehicle.

  The standard system power distribution box 20S distributes the power supply power (voltage is, for example, + 12V) supplied from the vehicle main power supply 10 via the power supply line 11 for each output system and supplies the power supply lines 31a and 31b. Although not shown, a plurality of fuses are arranged inside the standard system power distribution box 20S, and when an excessive current flows through the power supply line 31a or 31b due to a short circuit or the like, the current can be cut off on the upstream side. .

  In addition, about the ground wire 13 of each electric circuit, ie, an earth wire, since it is not contained in the wire harness 30 in the example of FIG. 1, each circuit is connected via a metal vehicle body. Of course, the ground wire 13 may be included as a part of the wire harness 30.

  In the configuration shown in FIG. 1, an expansion system power distribution box 20 </ b> E is provided to enable connection between the system on the vehicle and the expansion system electrical devices 51 to 56. Further, an expansion system sub-harness 32 that is a part of the wire harness 30 is connected to the expansion system power distribution box 20E.

  The configuration of the expansion system sub-harness 32 can be changed as necessary. However, in the example shown in FIG. Six systems of the spare 1 system trunk line 32e and the expansion spare system 2 trunk line 32f are included in the expansion system sub harness 32.

  Each of the trunk lines 32a to 32f is composed of one power supply line that supplies power supply power (voltage is +12 V, for example), and has a specification that allows a plurality of electrical devices to be connected to a single power supply line. In the configuration shown in FIG. 1, two expansion system electrical devices 51 (1) and 51 (2) are commonly connected to the power line of the expansion engine system trunk line 32a. In addition, three extended electrical devices 52 (1), 52 (2), and 52 (3) are commonly connected to the power line of the extended instrument panel main line 32b. Similarly, two expansion system electrical devices 53 (1) and 53 (2) are connected to the power line of the extended roof system main line 32c, and two expansion system electrical devices are connected to the power line of the expansion door system main line 32d. 54 (1) and 54 (2) are connected, one expansion system electrical equipment 55 (1) is connected to the power line of the expansion standby 1 system trunk line 32e, and the power supply line of the expansion backup system 2 trunk line 32f is connected One expansion system electrical equipment 56 (1) is connected.

  In addition, about the connection form of trunk line 32a-32f and expansion system electrical equipment 51 (1) -56 (1), the form which connects electric wires (WtoW), the form which connects via a short electric wire (Picktail W) / H), a configuration in which the electrical equipment is directly attached to the main wire harness 70 is conceivable. With such a connection method, options 51 (1) to 56 (1) can be retrofitted to the trunk lines 32a to 32f. In addition, the connection form with the trunk lines 32a to 32f can be different for each extension system electrical device. For example, as shown in FIG. 1, the expansion system electrical equipment 51 (2) is directly connected to the expansion engine system trunk line 32a, and the power supply line of the expansion system electrical equipment 51 (1) is expanded. It is also possible to make a wired connection so as to be attached to the engine main line 32a.

  The input side of the extended system power distribution box 20E is connected to the output of the on-vehicle main power source 10 via the main fuse MF2 and the power line 12. The expansion system power distribution box 20E distributes the power supplied from the on-vehicle main power supply 10 via the power line 12 to a plurality of systems, and distributes the power to the trunk lines 32a to 32f of the expansion system sub harness 32 connected under the system. Supply each. As will be described later, since the extended power distribution box 20E has a function of an electronic fuse, when an abnormally large current flows through each of the trunk lines 32a to 32f, this is detected and the current is interrupted instantaneously. can do.

  Each of the power lines of the trunk lines 32a to 32f is covered with an electrically insulating coating so that they are not in electrical contact with each other or in contact with the surroundings. In addition, any electrical connection method such as “pressure welding”, “adhesion”, “welding”, or the like may be used for electrical connection between the trunk lines 32a to 32f and the expansion system electrical devices 51 to 56.

  As shown in FIG. 1, a plurality of expansion-system electrical devices 51 to 56 can be commonly connected to the trunk lines 32a to 32f. Therefore, compared with the total number of the extension system electrical devices 51 to 56 connected under the extension system subharness 32, the number of electric wires constituting the extension system subharness 32 can be greatly reduced. That is, no matter how many expansion system electrical devices 51 are connected to the expansion engine system trunk line 32a, the expansion engine system trunk line 32a has only one power line, and the expansion system configured by the trunk lines 32a to 32f. The number of wires in the sub harness 32 is six. As a result, the types and product numbers of the wire harness 30 that should be prepared in advance corresponding to the difference in the vehicle type, grade, destination, etc. of the vehicle can be greatly reduced, and the cost can be reduced.

<Configuration of expansion system power distribution box 20E>
The internal configuration of the extended system power distribution box 20E is shown in FIG. The extended system power distribution box 20E shown in FIG. 2 includes a microcomputer (CPU) 21, a voltage adjustment circuit 22, a nonvolatile memory 23, IPD (Intelligent Power Device) 24 (1) to 24 (6), and an input-side power line. 25 and a connector 26 are incorporated.

  The power supply power (for example, + 12V) supplied from the on-vehicle main power supply 10 is supplied to the input-side power supply line 25 in the expansion system power distribution box 20E via the main fuse MF2. The output of the input side power supply line 25 is branched into a plurality of systems, and one system is connected to the power supply line of the extended engine system trunk line 32a via the IPD 24 (1). Another system is connected to the power line of the extended instrument panel trunk line 32b via the IPD 24 (2). Similarly, the outputs of the IPDs 24 (3), 24 (4), 24 (5), and 24 (6) are connected to the power lines of the trunk lines 32c to 32f, respectively.

  Therefore, the power supply supplied to the input-side power supply line 25 is distributed to a plurality of output systems and is output from the IPDs 24 (1) to 24 (6) to the trunk lines 32a to 32f, respectively. A part of the power of the input side power supply line 25 is also supplied to the input of the voltage adjustment circuit 22.

  Each of the six IPDs 24 (1) to 24 (6) functions as a switching unit that switches energization of a load. Each of the six IPDs 24 (1) to 24 (6) incorporates peripheral circuits such as an output current detection function, a gate driver, and various protection circuits in addition to the switching element (power MOSFET).

  The microcomputer 21 operates based on the power supply supplied from the voltage adjustment circuit 22, and implements a control function required for the extended system power distribution box 20E by executing a program incorporated in advance. This control function includes the function of an electronic fuse.

  As shown in FIG. 2, the microcomputer 21 is connected to the IPDs 24 (1) to 24 (6) and the nonvolatile memory 23. The microcomputer 21 controls the switching elements of the IPDs 24 (1) to 24 (6) by turning on / off control signals output to the IPDs 24 (1) to 24 (6) or controlling the duty of the pulses. The current flowing to the electrical equipment side via the harness 32 can be controlled.

  Further, the microcomputer 21 constantly monitors the magnitude of the current flowing to the load side for each output system, and shuts off the current by turning off the corresponding switching element when an overcurrent is detected. That is, it functions as an electronic fuse. The threshold value for identifying whether or not the monitored current is an overcurrent is written in the nonvolatile memory 23 as rewritable data. Therefore, the microcomputer 21 compares the current value detected by each of the IPDs 24 (1) to 24 (6) with the threshold value stored in the nonvolatile memory 23, thereby identifying whether or not there is an overcurrent.

  The nonvolatile memory 23 is configured by, for example, an EEPROM (Electrically Erasable Programmable Read-Only Memory), and can self-hold written data even when no power is supplied. Also, the written data can be electrically erased and rewritten with new data. The nonvolatile memory 23 of the present embodiment holds data including a threshold value for the electronic fuse function as will be described later.

  That is, the threshold value for identifying whether or not the magnitude of the load current flowing from the IPD 24 (1) to the power line of the extended engine main line 32a is an overcurrent, or the power line of the extended instrument main line 32b from the IPD 24 (2). A threshold value for identifying whether or not the magnitude of the flowing load current is an overcurrent is written in the nonvolatile memory 23.

  The threshold data stored in the nonvolatile memory 23 is updated manually or automatically so as to match the current consumption in the actual configuration. For example, with regard to the overcurrent threshold as a condition for shutting off the IPD 24 (1), the current consumed by the expansion system electrical devices 51 (1) and 51 (2) actually connected to the power line of the expansion engine system trunk line 32a It is adjusted to the size of As for the overcurrent threshold as a condition for shutting off the IPD 24 (2), the expansion system electrical devices 52 (1), 52 (2), 52 (3) actually connected to the power line of the expansion instrument system trunk line 32b are used. ) Is adjusted according to the amount of current consumed.

  The voltage adjustment circuit 22 generates power supply power of a stable DC voltage (for example, +5 V) required by a circuit such as the microcomputer 21 from the power supply voltage supplied to the input-side power supply line 25.

  In the actual expansion system power distribution box 20E, the number of IPDs 24 (1) to 24 (6) mounted is changed according to the presence or absence of the expansion system electrical equipment 51 to 56 mounted on the vehicle. For example, in an environment in which the expansion system electrical devices 55 (1) and 56 (1) shown in FIG. 1 are not mounted on a vehicle, the expansion backup system 1 trunk line 32e and the expansion backup system 2 trunk line 32f are unnecessary, and these currents Also, the IPDs 24 (5) and 24 (6) for controlling are unnecessary.

<Configuration of overcurrent threshold table>
A configuration example of the overcurrent threshold table TBL1 is shown in FIG. That is, the non-volatile memory 23 of the present embodiment holds an overcurrent threshold table TBL1 as shown in FIG. 3 as data including a current cutoff threshold used by the electronic fuse. The contents of this overcurrent threshold table TBL1 are updated as necessary.

  The overcurrent threshold table TBL1 shown in FIG. 3 holds the individual current reference value CurX, the added current reference value CurXref, the current cutoff threshold CurX_TH, and error information for each output system (X) corresponding to each of the trunk lines 32a to 32f. can do. In addition, since a plurality of electrical devices can be connected to each output system, the individual current reference values CurX of the plurality of devices can be respectively held.

  For example, the individual current reference value “CurA1” in the overcurrent threshold table TBL1 of FIG. 3 is consumed normally when the first expansion system electrical equipment 51 (1) connected to the expansion engine system trunk line 32a operates alone. Represents the measured value of the power supply current. The individual current reference value “CurA2” represents a measured value of the normal power supply current consumed when the second expansion system electrical equipment 51 (2) connected to the expansion engine system trunk line 32a operates independently.

  Further, the added current reference value “CurAref” in the overcurrent threshold table TBL1 of FIG. 3 is consumed when all the expansion system electrical devices 51 (1) and 51 (2) connected to the expansion engine system trunk line 32a operate simultaneously. Indicates the measured value of the power supply current at normal operation.

Further, the current cutoff threshold CurA_TH in the overcurrent threshold table TBL1 of FIG.
The threshold value is determined based on the added current reference value “CurAref” or the individual current reference values “CurA1” and “CurA2”. The electronic fuse provided in the extended system power distribution box 20E controls the IPD 24 to interrupt the current when the magnitude of the load current flowing through each output system exceeds the current cutoff threshold CurX_TH. The error information on the overcurrent threshold table TBL1 is information used for grasping whether or not a problem has occurred in the system.

<Diagnostic mode operation>
An example of operation in the diagnostic mode is shown in FIG. That is, the microcomputer 21 in the expansion system power distribution box 20E shown in FIG. 2 executes the operation in the diagnosis mode shown in FIG. 4 to match the expansion system electrical devices 51 to 56 actually connected. It is possible to automatically update the contents of the overcurrent threshold table TBL1 shown in FIG. 3 and automatically determine an appropriate current cutoff threshold.

  Note that the conditions for executing the operation in the diagnostic mode shown in FIG. 4 may be, for example, the timing immediately after the ignition switch of the vehicle is turned on or when a certain button is operated. The operation of FIG. 4 will be described below.

  In step S11, the microcomputer 21 measures the individual current reference value “CurX” of the first electrical equipment connected to the subordinate system for each output system of the expansion system power distribution box 20E, and uses the measured value as an overcurrent. Store in the threshold table TBL1.

  For example, when diagnosing the output system of the expansion engine system trunk line 32a, the first expansion system electrical device 51 (1) is operated in a normal state and the other expansion system electrical device 51 (2) is de-energized ( The individual current reference value “CurA1” can be acquired by sampling the value of the load current detected by the IPD 24 (1) in a state where the power is off.

  Note that individual control of the plurality of expansion-system electrical devices 51 (1) and 51 (2) can be realized by communication between a host electronic control unit (ECU) (not shown) and the microcomputer 21. is there.

  In step S12, the microcomputer 21 measures the individual current reference value “CurX” of the next (first and subsequent) electrical equipment connected to the subordinates for each output system of the expansion system power distribution box 20E. The measured value is stored in the overcurrent threshold table TBL1.

  For example, when measuring the individual current reference value “CurA2” of the second expansion system electrical equipment 51 (2) connected to the expansion engine system trunk line 32a, the first expansion system electrical equipment 51 (1) is not used. Switching to the energized state, sampling the load current value detected by the IPD 24 (1) in the state where the second extended system electrical equipment 51 (2) is operated in the normal state, and the individual current reference value “CurA2” To get.

  The microcomputer 21 repeatedly executes the process of step S12 for all the extended electrical devices of each output system. Then, when the processing of all the extended system electrical devices is completed, the process proceeds from S13 to S14.

  In step S14, the microcomputer 21 determines the magnitude of the load current when all the electrical equipment connected under the operation of each output system of the extended system power distribution box 20E is operating in a normal state. Measurement is performed as the additional current reference value CurXref, and this measured value is stored in the overcurrent threshold table TBL1.

  For example, when measuring the additional current reference value CurAref of the expansion engine system trunk line 32a, the IPD 24 is switched in a state where both of the connected expansion system electrical devices 51 (1) and 51 (2) are switched to the normal operation state. The value of the load current detected in (1) is sampled, and this value is set as the added current reference value “CurAref”.

  In step S15, the microcomputer 21 compares the sum of individual current reference values “ΣCurX” with the added current reference value “CurXref” on the overcurrent threshold table TBL1 for each output system. If “ΣCurX” and “CurXref” are substantially equal, the process proceeds from S15 to S16, and if they do not match, the process proceeds to S17.

  For example, for the output system of the extended engine system main line 32a, since the two extended system electrical devices 51 (1) and 51 (2) are connected, the two individual current reference values “CurA1” on the overcurrent threshold table TBL1 are connected. ] And “CurA2” are added to obtain the sum “ΣCurA”.

  For example, if the current values measured in S11 and S12 are relatively stable and the current measurement operation can be executed normally, “ΣCurX” and “CurXref” are almost the same. Proceed to On the other hand, when the fluctuation of the current value measured in S11 and S12 is severe, or when an abnormality occurs during the current measurement operation, the comparison is made between “ΣCurX” and “CurXref”. Since there is a high possibility that a large difference will appear, the process proceeds to S17.

  In step S16, the microcomputer 21 automatically calculates an appropriate current cutoff threshold CurX_TH for each output system based on the added current reference value “CurXref” on the overcurrent threshold table TBL1, and the overcurrent threshold table TBL1. To remember. As a specific example, it can be calculated by the following equation.

CurX_TH = “CurXref” + “K1_X” + “K2_X”
“K1_X”: a constant “K2_X” representing a maximum value of the expected normal current fluctuation amount: a constant corresponding to a margin

  In step S17, the microcomputer 21 executes predetermined error processing. For example, information indicating that an error has occurred is written as error information on the overcurrent threshold table TBL1, and further, the fact that the operation of the system is in an abnormal state is displayed using an abnormality display function on the vehicle. An error is notified.

  When the processes of S14 to S16 are repeated and the update of the data of the overcurrent threshold table TBL1 is completed for all the expansion system electrical devices 51 to 56 connected under the expansion system subharness 32, the process of FIG.

  After the update of the data of the overcurrent threshold table TBL1 is completed by the processing of FIG. 4, the microcomputer 21 constantly monitors the magnitude of the load current flowing through each of the trunk lines 32a to 32f, the detected current value, The current cutoff threshold CurX_TH on the current threshold table TBL1 is compared. When the current value exceeds the current cutoff threshold value CurX_TH, the IPD 24 that controls the current of each relevant main line is switched to non-conduction to cut off the output current. That is, it functions as an electronic fuse.

<Advantages of vehicle electrical equipment connection system>
The above-described vehicle electrical equipment connection system has the following advantages.
(1) Even if the configuration of the expansion system sub-harness 32 connected under the expansion system power distribution box 20E is not changed, one or a plurality of expansion system electrical devices 51 are connected to any one of the trunk lines 32a to 32f of each system. ~ 56 can be connected. Further, for example, an extension system electrical device can be added later according to a user's request.

(2) For the trunk lines 32a to 32f of each system of the expansion system sub-harness 32, it is allowed to connect a plurality of expansion system electrical devices to a single power line. In addition, the number of power supply lines constituting the extended system sub-harness 32 can be reduced. As a result, when different types of wire harnesses are prepared in advance for various vehicle types, various grades, various destinations, etc., the types and product numbers of wire harnesses to be prepared are reduced, and the manufacturing process is simplified. Or cost reduction.

(3) Since the expansion system power distribution box 20E incorporates an electronic fuse, it occupies less space than when a physical fuse is used, and the expansion system power distribution box 20E can be downsized. .

(4) Since the electronic fuse of the expansion system power distribution box 20E uses the current cutoff threshold held in the nonvolatile memory 23, the expansion system electrical equipment 51 to 56 connected under the expansion system power distribution box 20E The current cutoff threshold of the electronic fuse can be changed according to the actual configuration.

(5) When the operation shown in FIG. 4 is executed, the current interruption of the electronic fuse is performed in accordance with the actual current consumption characteristics of the extension system electrical devices 51 to 56 connected under the extension system power distribution box 20E. The threshold value can be automatically updated to an appropriate value.

Here, the characteristics of the embodiment of the vehicle electrical device connection system according to the present invention described above are briefly summarized and listed in the following (1) to (5), respectively.
(1) A vehicle electrical equipment connection system for connecting a plurality of electrical equipment to an electrical system of a vehicle via a wire harness (30) and supplying power to each electrical equipment from at least the vehicle side,
A standard that distributes power from a power supply on the vehicle (main power supply 10 on the vehicle) and supplies power to each of a plurality of trunk lines (power supply lines 31a and 31b) of the standard system (standard subharness 31) of the wire harness. System power distribution unit (standard system power distribution box 20S),
Expansion system power distribution unit (expansion system power distribution box) that distributes power from the power source and supplies power to each of a plurality of trunk lines (trunk lines 32a to 32f) of the expansion system (expansion system subharness 32) of the wire harness 20E),
A vehicle electrical equipment connection system comprising:
(2) The extension system power distribution unit is provided with a switching unit (IPD24) for each of a plurality of trunk lines of the extension system of the wire harness,
A plurality of expansion system electrical devices are connected to the switching unit via the trunk line.
The vehicle electrical equipment connection system according to (1) above, wherein
(3) The extension system electrical equipment is wired by the power supply line of the extension system electrical equipment being retrofitted to the main line.
The vehicle electrical equipment connection system according to (2) above, wherein
(4) As a plurality of expansion system electrical devices, the first expansion system electrical device and the second expansion system electrical device,
The first expansion system electrical equipment is directly connected to the trunk line,
The vehicle electrical equipment according to (2) above, wherein the second extension system electrical equipment is wiredly connected by retrofitting a power line of the second extension system electrical equipment to the main line. Equipment connection system.
(5) An electronic fuse that is disposed in the expansion system power distribution unit and that blocks a corresponding current when the magnitude of a current flowing through each of the plurality of trunk lines of the expansion system of the wire harness exceeds a cutoff threshold;
A storage unit (nonvolatile memory 23) that stores data of a cutoff threshold used by the electronic fuse;
The vehicle electrical equipment connection system according to any one of the above (1) to (4), characterized by comprising:

DESCRIPTION OF SYMBOLS 10 Main power supply on vehicle 11, 12 Power supply line 13 Ground line 20S Standard system power distribution box 20E Expansion system power distribution box 21 Microcomputer 22 Voltage adjustment circuit 23 Non-volatile memory 24 IPD
25 Input-side power line 26 Connector 30 Wire harness 31 Standard system sub harness 32 Expansion system sub harness 32a Expansion engine system trunk line 32b Expansion instrument system system trunk line 32c Expansion roof system system trunk line 32d Expansion door system system trunk line 32e Expansion spare system 1 trunk line 32f Expansion spare 2 System main line 41, 42 Standard system electrical equipment 51-56 Extended system electrical equipment MF1, MF2 Main fuse CurX Individual current reference value CurXref Addition current reference value CurX_TH Current cutoff threshold TBL1 Overcurrent threshold table

Claims (5)

A vehicle electrical equipment connection system for connecting a plurality of electrical equipment to an electrical system of a vehicle via a wire harness and supplying power to each electrical equipment from at least the vehicle side,
A standard power distribution unit that distributes power from a power source on the vehicle and supplies power to each of a plurality of trunk lines of the standard system of the wire harness;
An extended power distribution unit that distributes power from the power supply and supplies power to each of a plurality of trunk lines of the extended system of the wire harness;
A vehicle electrical equipment connection system comprising: In the expansion system power distribution unit, a switching unit is provided for each of a plurality of trunk lines of the expansion system of the wire harness,
A plurality of expansion system electrical devices are connected to the switching unit via the trunk line.
The vehicle electrical equipment connection system according to claim 1. The expansion system electrical equipment is connected by wire by retrofitting a power line of the expansion system electrical equipment to the main line.
The vehicle electrical equipment connection system according to claim 2. As the plurality of expansion system electrical devices, the first expansion system electrical device and the second expansion system electrical device,
The first expansion system electrical equipment is directly connected to the trunk line,
The vehicular electrical equipment according to claim 2, wherein the second extended electrical equipment is wiredly connected by retrofitting a power line of the second extended electrical equipment to the main line. Connection system. An electronic fuse that is disposed in the expansion system power distribution unit and that blocks a corresponding current when the magnitude of a current flowing through each of the plurality of trunk lines of the expansion system of the wire harness exceeds a cutoff threshold;
A storage unit for storing data on a cutoff threshold used by the electronic fuse;
The vehicle electrical equipment connection system according to any one of claims 1 to 4, further comprising:

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