JP2005178778A - Power source terminal device for automobile and power supplying system of automobile - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce power cables concentrating in an ignition switch or a fuse box by dispersing distributing, energizing and cutting off functions of the ignition switch by using multiple communication and a semiconductor switching element. <P>SOLUTION: A power supply breaker for cutting off power source is arranged in the middle of a power source line from a battery power source, and from the power source breaker, a power source line is wired further. A power source terminal is set in the middle of the power source line, and electric power for electricity load is supplied therefrom. Distribution of the power source and control of power supply for electricity load is performed by multiplex communication. The the switching element for supplying power is able to have the fuse function by using an element with a self-protection function, thereby the fuse can be reduced, and not only a power line for control signal but also a power line for supplying power can be reduced. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The power supply device and method according to the present invention, the semiconductor circuit device or the collective wiring device used for the power supply device have been described in particular for an automobile. However, the basic technology is not limited to an automobile, and a large number of devices separated from a power source. The present invention can be widely applied to other vehicles having an electric load, such as trains, airplanes, and ships.

  In a conventional vehicle power supply device, a power source mounted on a vehicle and each of a number of electric loads are connected to each other by a long power line via a fusing fuse. When the power line is shorted, this fuse is blown to disconnect the electrical load from the power source.

In conventional control of electric loads on vehicles, controllers for controlling each electric load are integrated, and control signals for multiple electric loads are calculated with a few controllers having communication functions and calculation functions, and connected by communication lines. There is known a so-called aggregate wiring system that transmits a control signal to a connected terminal device and controls several electric loads connected to the terminal device (for example, US Pat.
4,771,382, 5,113,410, 4,855,896, 5,438,506, etc.).

  However, the power supply line is always wired directly from the power supply to each electric load or the drive circuit of the electric load, and the number of electric loads is equal to or more than the number of electric loads. It was filled with electric wires.

  The present invention basically has the main object of providing a new power supply device for a vehicle, and specifically aims at reducing the power supply line of the vehicle power supply device. An object of the present invention is to eliminate a blown fuse, and yet another object of the present invention is to provide a new power supply method, and yet another invention provides a new semiconductor circuit device for supplying power. In another aspect of the present invention, a new integrated wiring device integrated with a power supply control system is provided. In yet another aspect of the invention, a new power supply device for a specific electric load of an automobile is provided. The purpose is to do.

  In order to achieve the above object, a control device that centrally controls each electrical component or a power supply terminal that supplies power centrally is arranged near the location where the electrical components are concentrated, and a wire harness to the electrical component control device Reduce the number of wires to the minimum necessary. In addition, by using a semiconductor switching element with a built-in protection function in the control device, the functions of the relay and fuse are incorporated and maintenance-free, thereby eliminating the existing relay and fuse.

  In addition, relays and fuses can be abolished by making the drive elements that drive electrical components intelligent (functions that do not fail even when electrical components are short-circuited).

  The present invention mainly relates to a method for driving an electrical component load of a vehicle, and has an effect of reducing a fuse and a wire harness of the vehicle.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

  FIG. 1 is a system configuration diagram showing the entire system. This system is roughly divided into two power supply systems: a power supply system that supplies power to the load device and a starter motor system that is used to start the engine of the vehicle. The electric power supplied from the battery 1 is supplied to the starter relay 3 and the power breaker 5 via the main power cable 2. The starter relay 3 is a relay used to turn on and off the current of the starter motor 4 through which a large current flows. When the relay 3 is turned on, a current flows through the starter motor 4 and becomes a force for starting the engine.

  The power supplied to the power circuit breaker 5 is distributed to the power cables 6, 7, and 8 via the circuit breaker, and is connected to the power terminals 14, 15, and 16 connected to the power cables. In this embodiment, the power cable is discharged in a star shape around the power breaker 5 and connected to each power terminal, but it may be connected in a bus shape or a tree shape.

  The devices 18, 19, 20, 21, and 22 connected to each power supply terminal are load devices that operate by receiving power supply from the power supply terminal, and are motors and lamps, It may be some control device arranged. Normally, these load devices are directly driven by the operation position of the ignition key switch and other switches (for example, a headlamp lighting switch).

  The ignition key switch 9 is a switch operated by the engine key 10. In normal cases, selection of the power supply path, energization, and shutoff are controlled by the operation position of this switch. A signal (power line) output from the switch is stretched indefinitely through a fuse as a power source for driving each electric load in the vehicle.

  The first object of the present invention is to reduce the number of power lines stretched indefinitely and horizontally as much as possible.

  FIG. 2 is an internal configuration diagram of the power breaker 5. In this embodiment, a normal mechanical fuse that is melted by heat is used. Here, the fuses 6a, 7a, and 8a are inserted into the power cables 6, 7, and 8, respectively, for the purpose of protection against a short circuit accident of the power cable to the power terminal and a double failure of the power terminal.

  FIG. 3 shows a key insertion slot of the ignition switch 9 into which the engine key 10 is inserted. The engine key 10 is inserted into a rectangular hole in the center of the figure. This ignition switch can be rotated to four positions within the operating range when the engine key is inserted, and there are positions of “OFF”, “ACC”, “RUN”, and “START” from the left end, respectively.

  In the “OFF” position, a power supply other than the electric load that receives power supply directly from the battery 1 is cut off. In the “ACC” position, power is supplied to an accessory load such as a radio connected to the vehicle. The “RUN” position is a position for supplying power to an electric load necessary for driving the vehicle, and the “START” position is for turning on the starter relay 3 for rotating the starter motor 4 to start the engine. Position. In the present embodiment, the starter motor 4 can be rotated even if some abnormality occurs in the power supply control device according to the present invention and it does not function at all. For example, even if a sudden abnormality occurs in the railroad crossing, for example. The vehicle can be moved.

  FIG. 4 is an internal configuration diagram of the ignition switch 9. The signal lines 11, 12, and 13 connected to the ignition switch are respectively connected to switches A, B, and C that are internally connected to the vehicle body ground. ing. The signal line 11 is connected to the starter relay 3, and power is supplied to the starter motor 4 when the switch A is turned on. The signal lines 11, 12, and 13 are connected to the power terminals 15 and 16 and used as signal lines for knowing the position information of the ignition switch.

FIG. 5 is a truth table showing the relationship between the switch position of the ignition switch 9 and the built-in switches A, B, C. For example, when the ignition switch is in the “RUN” position, it indicates that the switch A is OFF, the switch B is ON, and the switch C is ON.

  FIG. 6 is an internal configuration diagram of the power supply terminal 14.

  The power supply circuit 30 is a stabilized power supply that supplies power to the internal circuit of the power supply terminal, and receives power supply from the power cable 6. This stabilization voltage is used for the communication IC 33 and the microcomputer 32 using the supply line 34. The data bus 35 is for performing data used for communication with other power supply terminals via the communication IC 33.

  The power line 31 is connected to the FETs 36 and 39 and is used as a power source for driving an electric load. FET is an abbreviation for field effect transistor and is a kind of load driving element. In the present invention, an FET having a temperature detecting function is employed.

  The temperature detection function is a function that automatically shuts off when the internal chip temperature of the FET exceeds 150 ° C. (in the case of the present embodiment) and protects the destruction of the element itself. In the present invention, such a switching element having a self-protection function is positively adopted 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 36 and 39 are ON / OFF controlled by the microcomputer 37 through the signal lines 37 and 40. When the FET 36 is turned on, the power of the power line 31 is supplied to the load device 18 through the load power supply line 38. Similarly, when the FET 39 is turned on, the power of the power line 31 is supplied to the load device 19 through the load power supply line 41.

  FIG. 7 is an internal block configuration diagram of the power supply terminal 16. The difference from the power supply terminal of FIG. 6 is that the three signals 11, 12, and 13 of the ignition switch 9 are taken in, and the functions of the other parts are the same, so they are omitted.

  The microcomputer 51 determines the position of the engine key of the ignition switch based on the taken information of the ignition switch 9 and notifies the data to all the power terminals connected to the system via the communication IC 52. Based on the information of the ignition switch thus informed, each power supply terminal supplies power to the electrical load connected to itself, thereby switching the power supply that has been concentrated on the ignition switch until now, Since the interruption function can be distributed efficiently, a thick power line that can withstand a large current connected to the ignition switch can be changed to a small current line. In addition, the number of fuses can be reduced by using an element having a self-protection function as a switching element for supplying power to be used in each power terminal. Furthermore, since the power lines that have been stretched in all directions can be simplified by the two functions described above, there is an advantage that the total number of power lines can be reduced as a whole vehicle.

  The power supply terminal may supply power to some control unit, a motor, or a lamp. There are various switches in the part where the electrical load is concentrated on the power terminal. For example, the power window opening switch on the driver's seat power window is turned on and the power window is turned on from the power terminal built in the driver's seat door. The motor may be operated so as to be opened.

Here, the switching element that supplies power to the electric load will be described.
FIG. 8 shows a part of the power supply terminal 14 extracted. The FET 36 indicates a portion for supplying the power of the power line 31 to the load device 18 by the drive signal 37 from the microcomputer 32. The drive relationship and the operation when the load device 18 is short-circuited at the output signal line 38 will be described with reference to FIG.

  FIG. 9 is a timing chart showing the drive signal 37, the load state, and the output state at that time. Normally, the relationship between the load drive signal and the output signal is correlated, and when the drive signal becomes “HI”, the output signal also becomes “HI”, and power is supplied to the load device 18. 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 rises. As described above, in this embodiment, an FET having a temperature detection function is used, so that the output signal is automatically cut off when the chip temperature rises and exceeds 150 ° C. In FIG. 9, the temperature detection delay time is a time lag until automatic shut-off. Since the actual time is about a few milliseconds, it shuts off at a sufficiently early time compared to conventional fuses. Therefore, since the bimetal temperature circuit breaker for preventing burnout of the armature coil currently built in the power window motor or the like can be deleted from the motor, the cost of the entire vehicle can be further reduced.

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

First, referring to FIG. 10, the part that takes in the signal of the ignition switch 9 will be described. This process is performed in a fixed-time interrupt process in which the microcomputer 51 of the power supply terminal 16 is repeatedly executed at regular intervals. The reason why processing is performed at a fixed time is that it is easy to perform filter processing that removes chattering of the switch. First, it is determined in step 101 whether or not the accessory switch (switch C in FIG. 4) is ON. If it is ON, an “IGN (ACC)” flag indicating that the accessory switch is ON is set to “1” in step 102. Set to "". If not, the flag is cleared to “0” in step 103.

  Subsequently, at step 204, it is determined whether or not the ignition RUN switch (switch B in FIG. 4) is ON. Similarly, if the switch is ON, the flag “IGN (ON)” is set to “1” in step 105, and if not, it is cleared to “0” in step 106. Finally, in step 107, it is determined whether or not the ignition START switch (switch A in FIG. 4) is ON. Similarly, if the switch is ON, the flag “IGN (ON)” is set to “1” in step 108, and if not, step 109 is cleared to “0” and the process is terminated.

  By the way, it is important for the vehicle to operate the ignition switch with the engine key. If the wrong capture is performed, the present invention leads to a wrong control of the power supply. Therefore, the signal capture of this ignition switch is duplicated. In FIG. 1, the ignition switch signal is taken into the power terminals 15 and 16, and another reason, for example, the power cable 8 causes a short circuit accident and the fuse 8 a of the power circuit breaker 5 is blown. Even so, the state of the ignition switch is not lost.

  Therefore, the same processing flow as that in FIG. 10 is also executed in the microcomputer in the power supply terminal 15. That is the process of taking the ignition switch signal implemented by the microcomputer of the power supply terminal 15 of FIG. Basically, the processing is exactly the same as in FIG.

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

  FIG. 12 is a flowchart of data transmission processing 300 performed by the microcomputer. In step 301, a comparison is first made between the previously transmitted data and the data fetched by the above-described fixed time interrupt processing. If the data match at step 302 (the switch input has not changed), the process is terminated and data transmission is not performed. If there is a change in the input of the switch, in step 303, the data fetched this time is set as transmission data in the communication IC 81, and in step 304, a transmission command is issued to the communication IC. Subsequently, the data (transmitted data) captured in step 305 is stored as previously transmitted data, and the process ends.

  Next, the receiving process will be described. Since the communication IC basically has a function of notifying that the data has been received when the data is received, in this embodiment, an interrupt process is executed with this signal to perform a process of sucking up the data received by the communication IC. Yes. This process is a data reception process 400 shown in FIG.

  In step 401, the address of the transmitting station is obtained in order to determine where the received data is transmitted from. Subsequently, the received data is obtained in step 402, the address of the RAM where the received data is to be stored is decoded based on the address of step 401 in step 403, and the data is stored in the RAM in step 404 for processing. Exit. In this way, by securing an area for storing data exclusively for each transmitting station in the RAM, data necessary for other processing can be obtained immediately by referring to the RAM.

  FIG. 14 is an abnormality determination flow of the above-described two ignition switch capturing processes (FIGS. 10 and 11). In step 501, the information captured in the switch signal capturing process 1 in FIG. 10 is compared with the information captured in the switch signal capturing process 2 in FIG. The stop is implemented and ends. The alarm here is omitted as long as it can inform the driver that there is an abnormality in the vehicle.

  If they do not match in step 501, in step 502, a comparison is made between the power supply status output so far and the output status of both ignition switches. In step 503, the input state of the mismatched switch signal capturing process is ignored, and in step 504, an abnormality alarm is output.

  As described above, since it is possible to instruct the power supply without any mistake by judging the abnormality from the power supply status that has been output so far, it is possible to prevent malfunction caused by taking in the ignition switch.

  Next, a process in which the power terminal supplies power based on these pieces of information will be described in a power supply process 600 of the power terminal 14 in FIG.

  First, in step 601, it is checked with a flag “IGN (ST)” whether the ignition switch is in the “START” position. This flag is the data set in FIG. 10 or FIG.

  When the engine is in the starter position, that is, when the engine is about to be started, in this case, the FET 36 is turned OFF at step 603. This is a process performed to suppress unnecessary power consumption for starting the engine.

  If the ignition switch is not in the “START” position in step 601, it is checked in step 602 with the flag “IGN (ACC)” whether the accessory power switch of the ignition switch is ON. If the flag “IGN (ACC)” is “1”, in step 604, the drive signal 37 is set to “high” to turn on the FET 36. If the flag “IGN (ACC)” is “0”, the drive signal 37 is set to “low” in step 603. Therefore, it can be seen that the FET 36 is a switching element that supplies power to the load device 18 to which power is supplied when the ignition switch is in the accessory position.

  Next, in step 605, it is determined by the flag “IGN (ON)” whether or not the ignition switch is ON. This flag is also the data set in FIG. 10 or 11 as in the above-mentioned “IGN (ACC)”. If the flag “IGN (ON)” is “1”, the drive signal 40 is set to “high” to turn on the FET 39 in step 607. If it is “0”, the drive signal 40 is set to “low” in step 606 and the process is terminated. From this, it can be seen that the FET 39 is a switching element that supplies power to the load device 19 to which power is supplied when the ignition switch is in the ON position.

  As described above, a power breaker that shuts off the power supply is arranged in the middle of the power supply line from the battery power supply, and a power supply line is further wired from the power breaker. Furthermore, a power terminal is installed in the middle of the power line, and power is supplied from there to the electric load. In addition, by distributing power and controlling power supply to the electrical load through multiplex communication, the power lines concentrated around the ignition switch can be thinned, and self-protecting elements are used as switching elements that supply power By doing so, the switching function can be provided to the switching element, so that the number of fuses can be reduced, so that it is possible to construct a system that can reduce not only the control signal wires but also the power supply wires.

  Note that the function of the ignition key (engine key) switch that mechanically supplies power is distributed using multiplex communication, and ON / OFF of the power supply device that is optimally arranged for the electrical load is communicated. By implementing using the power supply line, it is possible to save the power line related to the ignition key.

1 is a system configuration diagram showing an embodiment of the present invention. It is a block diagram of the power circuit breaker used for one Example of this invention. It is explanatory drawing of the ignition switch used for one Example of this invention. It is explanatory drawing of the ignition switch used for one Example of this invention. It is explanatory drawing of the ignition switch used for one Example of this invention. It is an internal block diagram which shows one Example of this invention. It is an internal block diagram which shows one Example of this invention. It is an internal block diagram which shows one Example of this invention. It is a timing chart which shows one Example of this invention. It is a flowchart which shows the operation principle of this invention. It is a flowchart which shows the operation principle of this invention. It is a flowchart which shows the operation principle of this invention. It is a flowchart which shows the operation principle of this invention. It is a flowchart which shows the operation principle of this invention. It is a flowchart which shows the operation principle of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Battery, 2 ... Main power cable, 3 ... Starter relay, 4 ... Starter motor, 5 ... Power circuit breaker, 6, 7, 8 ... Power cable, 9 ... Ignition switch, 10 ... Engine key, 14, 15, 16 ... power terminal, 17 ... communication line, 18, 19, 20, 21, 22 ... load device.

Claims (2)

  In an electric load driving device having a structure in which a control device that centrally controls each electric component is arranged near a location where electric components mounted on an automobile are concentrated, a tree of power cables supplied to a plurality of electric load driving devices Or in a star shape and at least one of the power cables wired in a tree shape or star shape causes a short circuit accident on a part of the power cable wired in the tree shape or star shape. However, the vehicle power supply control device is provided with a power supply circuit breaker so as not to affect other power supply cables. In an electrical load drive device having a structure in which a control device for centrally controlling each electrical component is arranged near a location where electrical components mounted on an automobile are concentrated, an excessive load is applied to a switching element for supplying power to the electrical component. A vehicle power supply control device using a semiconductor element with a temperature cutoff function that can automatically cut off power supply by detecting temperature.

Images