JP2000016200A - Power supply control device for vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To save wiring by arranging a control device centralizedly controlling respective electrical equipment or an electrical power source terminal end centralizedly supplying source power nearby a place concentrated with the electrical equipment, and limiting wireharness to the electrical equipment control device to be necessary and of the lowest limit. SOLUTION: Electric power supplied from a battery 1 is, after passing through a fusible link 2, supplied to an electric power source relay 5 for an engine control device supplying power to the engine control device 6 and a power supply breaker 4, through a main power supply cable 3. The electric power supplied to the power supply breaker 4 is respectively distributed to power supply cables 9-14 through interception elements, and they are connected to power supply terminal ends 15-20 connected to the respective power supply cables. The power supply cables are emitted star-likely centering around the power supply breaker 4 to be connected to the respective power supply terminal ends, or connected bus-likely or tree-likely. Power supply wires for power supply through an ignition key switch 31 are saved to the utmost.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The power supply apparatus and method according to the present invention, and the semiconductor circuit device or the integrated wiring device used for the power supply apparatus and the integrated wiring apparatus have been particularly described in connection with an embodiment for an automobile, but the basic technology is not limited to an automobile. It can be widely applied to other vehicles having a large number of electric loads far from the power source, such as trains, airplanes, and ships.

[0002]

2. Description of the Related Art In a conventional vehicle power supply device, a long power supply line is connected between a power supply mounted on a vehicle and each of a number of electric loads via a fusing fuse. When the power supply line is short-circuited, the fuse is blown to disconnect the electric load from the power supply. In conventional vehicle electric load control, a controller for controlling each electric load is integrated, and control signals for a plurality of electric loads are calculated by a small number of controllers having a communication function and a calculation function, and connected by a communication line. There is known a so-called centralized wiring system that transmits a control signal to a terminal device and controls some electric loads connected to the terminal device (for example, US Pat. No. 4,771,
No. 382, 5,113,410, 4,855,896, 5,438,506, etc.).

[0003] However, the power supply line is still wired directly from the power supply to each electric load or the drive circuit of the electric load, so that the number of power supply lines is equal to or larger than the number of electric loads, and the floor, the ceiling and the body of the vehicle are required. The inside was filled with wires.

[0004]

SUMMARY OF THE INVENTION The object of the present invention is basically to provide a new power supply for a vehicle, and more specifically, to reduce the power lines of the power supply for a vehicle. For one purpose, and in another invention,
It is an object of the present invention to reduce the number of blown fuses, to provide a new power supply method in still another invention, and to provide a new semiconductor circuit device for supplying power in yet another invention. Another object of the present invention is to provide a new integrated wiring device integrated with a power supply control system,
Yet another object of the present invention is to provide a new power supply device for a specific electric load of an automobile.

[0005]

In order to achieve the above object, a control device for centrally controlling each electrical component or a power supply terminal for centrally supplying power is arranged near a location where the electrical components are concentrated. In addition, the wire harness to the electrical component control device is limited to the minimum necessary to reduce the number of wires. Further, by using a semiconductor switching element having a protection function in the control device, the function of the fuse is taken in and the maintenance-free operation is performed, thereby reducing the number of existing fuses.

[0006] The function of an ignition key (engine key) switch for mechanically supplying power is distributed using multiplex communication, and the ON / OFF of a power supply device optimally arranged for an electric load is communicated. By using the data, the power supply line related to the ignition key can be saved. In addition, fuses can be reduced by making the driving elements for driving the electrical components intelligent (a function that does not cause a failure even if a short circuit occurs in the electrical components).

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a system configuration diagram showing the entire system. This system is roughly divided into a power supply system for supplying power to the load device, and two power systems for supplying power to the engine control device. After the electric power supplied from the battery 1 passes through the fusible link 2,
The power supply is divided into an engine control device power supply relay 5 for supplying power to an engine control device (ECU) 6 via the main power supply cable 3 and a power supply circuit breaker 4.

The fusible link 2 functions as protection when the main power cable 3 is short-circuited to the power cable up to the power circuit breaker 4 and the power cable to the engine controller. In addition, like the present invention, the power supply
It is safer to place the main power cable 3 as close to the battery as possible, since the probability of an accident that the main power cable 3 is short-circuited to the vehicle body can be reduced. The lower the failure rate per unit length).

The electric power supplied to the power supply breaker 4 is distributed to power supply cables 9 to 14 via the interruption device, and connected to power supply terminals 15 to 20 connected to the respective power supply cables. In the present embodiment, this power cable is discharged in a star shape around the power circuit breaker 4 and connected to each power terminal, but may be connected in a bus shape or a tree shape.

In addition, when the power cable is wired, it is not routed around the outer periphery of the vehicle body, but is routed through the central portion, so that it is less likely to be affected by a secondary disaster such as breakage of the power cable due to a traffic accident or the like. .

Devices 21 to 27 connected to each power supply terminal
Is a load device that operates by receiving power supply from the power supply terminal, which is a door unit that centrally controls a door lock motor or a power window motor, a radio or a navigation unit, or a vehicle. Or some kind of control device. Without relying on the invention, these load devices are usually powered directly by the operating position of the ignition key switch.

An ignition key switch 31 is a switch operated by an engine key 32. In the case of not relying on the present invention, usually the operation position of this switch
It controls the selection of the power supply path and the energization and cutoff. Through this switch, a power supply line for supplying electric power is run through the electric loads in the vehicle through fuses in a vertical and horizontal manner.

It is a first object of the present invention to reduce the power supply lines which are stretched endlessly and horizontally as much as possible. A second purpose is to reduce the number of fuses.

FIG. 2 shows the overall view of the system of FIG. 1 from a different perspective and is basically the same, but here, the signal lines 28 to 30 output from the ignition key switch 31 are shown. Details are shown.

Hereinafter, the details of each part will be described with reference to FIG.

FIG. 3 is a detailed view of the power cables 9 to 14 used in this embodiment. The power cable is of a type having therein a power line 33 for passing power and a communication line 34 for performing multiplex communication between the power terminals 15 to 20. It should be noted that there is no problem even if the power supply line 33 and the communication line 34 are not connected together but are separately wired.

FIG. 4 is an internal configuration diagram of the power supply relay for the engine control device. The power from the battery 1 to the main power supply cable 3 is supplied to the ECU by turning on the relay 5 when the voltage level of the signal line 30 becomes “Lo”.

FIG. 5 shows a key insertion opening of the ignition key switch 31 into which the engine key 32 is inserted.
The engine key 32 is inserted into a rectangular hole at the center of the figure. When the engine key 32 is inserted, the ignition key switch 31
Can be rotated to one of two positions.
F, ACC, RUN, and START.

An "OFF" position is a position where power other than an electric load which is directly supplied with power from the battery 1 is cut off, and an "ACC" position supplies power to an accessory load such as a radio connected to the vehicle. To the position
The “UN” position is a position for supplying power to an electric load necessary for driving the vehicle, and the “START” position is a position for rotating a starter motor M for starting the engine. FIG. 6 is an internal configuration diagram of the ignition key switch 31. Each of the signal lines 28, 29, 30 connected to the ignition switch is connected to contacts 36 to 38 which are in contact with a sliding switch 35 which is internally connected to the vehicle body ground (ground). Sliding switch 35
Are contacts having a certain width, and FIG. 6 shows a state where the key switch is at the “ACC” position. When the key switch is in the "RUN" position, the contacts 36 and 37 are connected to the vehicle body ground, and when the key switch is in the "START" position, the contacts 37 and 38 are connected to the vehicle body ground. It is supposed to. Thus, during operation to the START position, a current flows through the coil of the starter relay via the power supply line 29 to turn on the starter relay contact, and power is supplied from the battery to the starter motor M via the fuse 2.

The signal line 30 is connected to the power supply relay 5 for the engine control device, and can directly control the power supply to the engine control device 6. In this way, even if the power supply control device has any abnormality and does not function at all, the start and stop of the engine of the vehicle can be operated independently. However, there is an advantage that the vehicle can be stopped.

FIG. 7 shows the switch position of the ignition key switch 31, the sliding switch 35 and the contact 3
39 is a truth table showing a relationship between each of signal lines 28 to 30 connected to 6 to 38. For example, when the ignition switch is in the “RUN” position, the signal line 29 is turned off.
F indicates that the signal line 28 is ON and the signal line 30 is ON.

FIG. 8 is an internal configuration diagram of the power supply breaker 4. In the present invention, a PTC element (a resistance element having a positive temperature coefficient) 39 is used here. Here, a PTC element 39 is inserted into each of the power cables 9 to 14,
Short-circuit accident of power cable to power terminal, power terminal 2
It is intended for protection in the event of a major failure. In the present invention,
Although PTC elements were used, semiconductor switching elements,
Ordinary blowing fuses may be used. But,
In consideration of user's convenience, it is desirable to use a PTC element or a bimetal element which is a self-recovery type interruption element, or a FET or an IPD (intelligent power device) which is a controllable semiconductor switching element. The PTC element will be described later.

The voltage level downstream of each PTC element 39 is
The signal line group 7 is connected to the display 8 and is used as a monitor signal of the cutoff state of the PTC element.

The communication line 3 of each of the power cables 9 to 14
4 has a structure in which the power supply line 33 and the communication line 34 are separately connected, as described above, there is no need to perform the collective connection here.

FIG. 9 shows the characteristics of the above-mentioned PTC element. The PTC element has a temperature characteristic as shown in FIG. 9A, and a certain temperature (about 120 ° C. in this embodiment).
When the temperature of the element increases as described above, the resistance value sharply increases. The resistance value of the PTC element in this embodiment increases from several tens of mΩ to several hundred kΩ. The temperature rise is caused by the current flowing through the PTC element. FIG. 9B shows the relationship between the current value and the time (trip time) until the resistance value rapidly increases. Three characteristics are described, which indicate that the ambient temperature is 0 ° C., 20 ° C.,
This is the characteristic at 60 ° C. (0 ° C., 20 ° C., and 60 ° C. are shown in order from the upper side in the curve in the figure). At a current of 40 A or more, the resistance value for one second or less increases. When a very large current flows through the PTC element, the resistance value of the PTC element increases, so that the current value is suppressed and the overcurrent does not continue to flow.

FIG. 10 is an internal configuration diagram of the display 8.
The current from the main power cable 3 includes a light emitting diode (LED) 40 and a resistor 41 for limiting the light emitting current.
And is connected to the power supply breaker 4 via the signal line group 7. In a state where the PTC element of the power supply breaker 4 is flowing a current (a normal state in which no overcurrent flows), the potential downstream of the PTC element is higher than the potential downstream of the resistor 41, Since no current flows through LED40, LED4
0 does not emit light.

Here, for example, it is assumed that the power supply line of the power supply cable 9 is short-circuited to the vehicle body ground. In this case, since the potential downstream of the PTC element 39 of the power supply breaker 4 becomes the same as the vehicle body ground, a large current flows from the battery 1 via the power supply breaker 4. When a large current flows, the resistance value of the PTC element increases, and the current is limited.
Further, since the downstream of the PTC element is at the same potential as the vehicle body ground, current flows through the LED 40 of the display 8 and the resistor 41, so that the LED 40 is turned on. The user can use this L
Lighting of the ED makes it possible to recognize that an abnormality has occurred in the power cable, so that the vehicle can be immediately brought to the repair shop. The warning on the display may be light or sound,
Also, the number of power cables may be sufficient or one. It is only necessary to know that the user has an abnormality.

FIG. 11 is an internal configuration diagram of the power supply terminal 18.

The power supply circuit 42 is a stabilized power supply for supplying power to the internal circuit of the power supply terminal, and receives power from the power supply cable 12. This stabilized voltage is used by the communication IC 43 and the microcomputer 44 using the supply line 45. The data bus 47 is for performing data used for communication with another power supply terminal via the communication IC 43.

The power line 46 is connected to the FETs 48 and 49 and is used as a power source for driving an electric load. FET
Is an abbreviation of a power effect transistor, which is a kind of load driving element. In this embodiment, a transistor having an overtemperature detecting function is employed.

The over-temperature detecting function is a function for automatically performing a shut-off operation when the internal chip temperature of the FET exceeds 150 ° C. (in the case of the present embodiment), thereby protecting the element itself from being destroyed. In the present invention, the switching element having such a self-protection function is positively employed to substitute the fuse function. By doing so, there is an advantage that fuses used in a large amount in the vehicle can be reduced.

The FETs 48 and 49 are controlled by the microcomputer 44
ON / OFF control is performed by the signal lines 50 and 51, and when the FET 48 is turned on, the power of the power line 46 is supplied to the navigation device 24. Similarly, FET
When 49 is turned on, it is supplied to the CD player device 25.

FIG. 12 is an internal block diagram of the power terminal 16. The difference from the power supply terminal in FIG. 11 is that the three signal lines 28 to 30 of the ignition key switch 31 are taken in, and the functions of the other parts are the same, so that they are omitted.

The microcomputer 54 determines the position of the engine key of the ignition switch based on the information of the received ignition key switch 31, and uses the information as a communication IC.
53, and inform the data to all power supply terminals (including the ECU 5 in FIG. 1) connected to the system via the communication line 34. Based on the information of the ignition switch notified in this way, each power supply terminal supplies power to the electric load connected thereto, thereby switching power supply, which has been concentrated on the ignition switch until now, switching on and off power supply. Since the cutoff function can be efficiently distributed, the thick power line that can withstand the large current connected to the ignition switch can be changed to a small current line, and the power used by each power terminal is supplied. By using an element having a self-protection function as the switching element, the number of fuses can be reduced. Furthermore, since the power lines that have been extended in all directions are simplified by the two functions described above, there is an advantage that the total number of power lines in the entire vehicle can be reduced.

It should be noted that the power supply terminal may supply power to any control unit, motor or lamp. There are various switches in the part where the electric load of the power supply terminal is concentrated.For example, when the open switch of the driver's seat power window is turned on, the power window is installed from the power terminal built in the driver's door. That is, the motor may be operated so as to open.

Here, the switching element supplying power to the electric load will be described. FIG. 13 shows a part of the power supply terminal 18 extracted. The FET 48 indicates a portion that supplies power of the power line 46 to the navigation device 24 by a drive signal 50 from the microcomputer 44. As described above, in the present embodiment, the FET having the over-temperature detection function is used for the FET.
The operation in the case where the electric wire connecting between them is short-circuited will be described with reference to FIG.

FIG. 14 is a timing chart showing the driving signal 50, the state of the load, and the output state at that time. Normally, the relationship between the load drive signal and the output signal is correlated, and if the drive signal becomes “HI”, the output signal also becomes “HI”.
, And power is supplied to the navigation device 24.
In this state, if the output signal is short-circuited to the vehicle body ground or the like, the output current increases, and the chip temperature of the FET 48 increases. As described above, since the present invention has an over-temperature detection function, the output signal is automatically cut off when the chip temperature rises and exceeds 150 ° C. (cut-off area). FIG.
The over-temperature detection delay time is a time lag until the automatic shut-off. The actual time is on the order of a few milliseconds, so the fuse will be blown in a much faster time than a conventional fuse. By using this element, the blower fuse currently inserted on the load side and the circuit breaker for preventing burnout of the armature coil of the motor built in the power window motor etc. can be deleted from the motor. Costs can be further reduced as a whole.

Hereinafter, the operation of the present invention will be described with reference to flowcharts.

First, a portion for taking in the signal of the ignition switch 31 will be described with reference to FIG. This process is performed in a fixed-time interrupt process that is repeatedly executed by the microcomputer 51 of the power supply terminal 20 at regular intervals. The reason why the processing is performed in a fixed time is that the filter processing for removing the chattering of the switch is easily performed.
First, it is determined in step 101 whether the accessory (ACC) switch (signal line 28 in FIG. 6) is ON. If it is ON, in step 102, "IGN1 (ACC)" indicating that the accessory switch is ON. The flag is set to "1". If not, step 1
At 03, the flag is cleared to "0".

Subsequently, at step 204, it is determined whether or not the RUN switch (the signal line 30 in FIG. 6) is ON. Similarly, if the switch is ON, the flag "IGN1 (ON)" is set to "1" in step 105, and if not, it is cleared to "0" in step 106. Finally, at step 107, the ignition STAR
It is determined whether the T switch (signal line 29 in FIG. 6) is ON. Similarly, if the switch is ON, the flag "IGN1 (ON)" is set to "1" in step 108, and if not, the step 109 is "0".
And the process ends.

Next, a process in which the microcomputer of each power supply terminal transmits data via the communication IC will be described.

FIG. 16 is a flowchart of a data transmission process 200 performed by the microcomputer. Step 201
First, the previously transmitted data is compared with the data fetched in the above-described fixed-time interrupt processing. If the data match in step 202 (the input of the switch does not change), the process is terminated as it is, and the data transmission is not performed. If there is a change in the input of the switch, in step 203, the data acquired this time is set as transmission data in the communication IC 53, and in step 204, the communication I
Sends a transmission command to C. Subsequently, the data (transmitted data) captured in step 205 is stored as previously transmitted data, and the process ends.

Next, the receiving process will be described. In general, the communication IC has a function of notifying that data has been received when data is received. Therefore, in the present embodiment, an interrupt process is executed by this signal to perform a process of collecting the data received by the communication IC. This processing is the data reception processing 300 shown in FIG.

In step 301, the address of the transmitting station is obtained to determine from where the received data was transmitted. Subsequently, in step 302, the received data is obtained. In step 303, the address of the RAM in which the received data is to be stored is decoded based on the address in step 301, and in step 304, the data is stored in the RAM. To end. In this way, by securing an area for storing data exclusively for each transmission station in the RAM, data required for other processing can be immediately obtained by referring to the RAM.

Next, a process of supplying power from the power supply terminal based on these pieces of information will be described with reference to a power supply process 400 of the power supply terminal 18 in FIG.

First, in step 401, it is checked whether or not the ignition switch is at the "START" position by a flag "IGN (ST)". This flag
This is the result of the data set in FIG. 15 determined by the processing in FIG.

When the engine is in the starter position, that is, when the engine is about to be started, in this case, in step 403, the FET 49 is turned off. This is a process performed to suppress unnecessary power consumption for starting the engine and give priority to power supply to the starter motor.

If it is determined in step 401 that the ignition switch is not in the "START" position, step 402
The flag “IGN (AC) indicates whether the accessory power switch of the ignition switch is ON.
C) ". Flag "IGN (ACC)"
Is "1", in step 404, the FET 49 is turned on.
The drive signal 51 is set to “high” in order to make it high. If the flag “IGN (ACC)” is “0”, the drive signal 51 is set to “low” in step 403. Therefore, FET49
Is a switching element that supplies power to the CD player device 25 to which power is supplied when the ignition switch is at the accessory position.

Next, at step 405, it is determined whether or not the ignition switch is turned on by the flag "IGN".
(ON) ". This flag is determined by the processing of FIG. 17 based on the data set in FIG. 15, similarly to the above-mentioned “IGN (ACC)”. Flag "IG
If "N (ON)" is "1", the drive signal 50 is set to "high" to turn on the FET 48 in step 407. If “0”, the driving signal 50 is
Is set to “low”, and the process is terminated. From this, FE
It can be seen that T48 is a switching element that supplies power to the navigation device 24 to which power is supplied when the ignition switch is at the ON position.

FIG. 19 shows a list of the relationship of power supply by these ignition switches.

As described above, the power supply breaker for interrupting the power supply is arranged in the middle of the power supply line from the battery power supply, and the power supply line is further wired from the power supply breaker. Further, a power supply terminal is installed in the middle of the power supply line, and power is supplied to the electric load from the power supply terminal. Also, by multiplexing the distribution of power and the control of power supply to the electric load, the power lines concentrated around the ignition switch can be made thinner, and the switching elements that supply power use elements with self-protection functions. By doing so, the switching element can be provided with a fuse function, so that the number of fuses can be reduced. Therefore, it is possible to construct a system capable of reducing not only control signal wires but also power supply wires.

[0053]

The present invention mainly relates to a method of driving the electric component load of a vehicle, and has an effect of reducing fuses and wire harnesses of the vehicle.

[Brief description of the drawings]

FIG. 1 is a system configuration diagram showing an embodiment of the present invention.

FIG. 2 is a system configuration diagram showing one embodiment of the present invention.

FIG. 3 is a configuration diagram of a power cable used in an embodiment of the present invention.

FIG. 4 is a configuration diagram of a relay used in one embodiment of the present invention.

FIG. 5 is an explanatory diagram of an ignition switch used in one embodiment of the present invention.

FIG. 6 is an explanatory diagram of an ignition switch used in one embodiment of the present invention.

FIG. 7 is an explanatory diagram of an ignition switch used in one embodiment of the present invention.

FIG. 8 is a configuration diagram of a power breaker used in one embodiment of the present invention.

FIG. 9 is a characteristic diagram of a blocking element used in one embodiment of the present invention.

FIG. 10 is an internal block diagram showing one embodiment of the present invention.

FIG. 11 is an internal block diagram showing one embodiment of the present invention.

FIG. 12 is an internal block diagram showing one embodiment of the present invention.

FIG. 13 is an internal block diagram showing one embodiment of the present invention.

FIG. 14 is an explanatory diagram of a load driving element used in one embodiment of the present invention.

FIG. 15 is a flowchart showing the operation principle of the present invention.

FIG. 16 is a flowchart showing the operation principle of the present invention.

FIG. 17 is a flowchart showing the operation principle of the present invention.

FIG. 18 is a flowchart showing the operation principle of the present invention.

FIG. 19 is a table showing the operation of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Battery, 2 ... Fusible link, 3 ... Main power cable, 4 ... Power breaker, 5 ... Relay, 6 ... Engine control device, 8 ... Display, 9-14 ... Power cable, 1
5 to 20 power supply terminals, 21 to 27 each electric load device, 2
8 to 30: ignition switch signal line, 31: ignition key switch, 32: engine key.

 ──────────────────────────────────────────────────の Continuing from the front page (72) Inventor ▲ Yoshi ▼ Tatsuya 2520 Oji Takaba, Hitachinaka City, Ibaraki Prefecture Inside the Hitachi, Ltd.Automotive Equipment Division (72) Inventor Hiroyuki Saito 2520 Oji Takaba, Hitachinaka City, Ibaraki Prefecture Address: Hitachi, Ltd.Automotive Equipment Division (72) Inventor Shinichi Sakamoto 2520, Oji Koba, Hitachinaka, Ibaraki Prefecture Hitachi, Ltd.Automotive Equipment Division (72) Inventor Kiyoshi Horibe 4-chome, Kanda Surugadai, Chiyoda-ku, Tokyo No. 6 F-term in Hitachi, Ltd. (reference) 5G003 AA07 BA01 DA04 FA01

Claims (5)

[Claims] A power supply control device for a vehicle, wherein a power supply breaker is installed near a battery, and power supply lines are wired in a star shape and / or a tree shape via the power supply breaker. 2. A power supply control device for a vehicle having a power supply cable extending back and forth in the vehicle traveling direction, wherein the power supply cable is routed so as to pass through a center portion of the vehicle. 3. A vehicle power supply control device having a power supply circuit breaker for interrupting an electric circuit in the middle of a power supply line, wherein the power supply circuit breaker includes a PTC element. 4. A power supply control system for a vehicle, comprising: a power supply breaker provided in a power supply path; and, when the power supply breaker cuts off a power supply line, a display device for displaying the cut off power supply system. apparatus. 5. The RUN of an ignition switch of a vehicle.
A relay coil is connected to the terminal, and power is supplied from the battery to the engine control unit through the contact point of the relay.
An N / START signal is separately input to a microcomputer via a signal line, and an ignition switch signal is transmitted from the microcomputer to another control device via a communication line.