JPH11240395A - Electrical circuit protector for vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electrical circuit protector for vehicle capable of, when each of electric cables composing a wire harness is short-circuited, detecting the short circuit with reliability and stopping a load dispatching to each load even if rush current is passed through each load or the temperature of each load and each electric cable is high, so that overheating of a wire harness can be positively prevented to dramatically enhance safety. SOLUTION: Electrical characteristics data and operating status historical data of each load 8 are registered in a memory circuit 2. When actuating current is fed to each load 8, an intelligent judgement on short circuits is performed by means of a CUP circuit 3 and a driver circuit 6 using the electrical characteristics data and the operating status historical data of each load 8 registered in the memory circuit 2, and taking outside-air temperature of the area around a vehicle, the speed of the vehicle, and load operation status into account.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicular electric circuit protection device for protecting an electric circuit mounted on a vehicle, and more particularly to a vehicular electric circuit for quickly protecting an electric circuit by estimating a load state. The present invention relates to a circuit protection device.

[0002]

2. Description of the Related Art In a vehicle electric circuit protection device for protecting an electric circuit mounted on a vehicle, for example, when a core wire of an electric wire constituting a wire harness comes into contact with a body or the like, an overcurrent is generated by using a shunt resistor or the like. Is detected, and based on the detection result, the relay device is operated to stop supplying power to the wire harness, thereby preventing overheating of the wire harness and the like.

[0003]

However, the above-described conventional electric circuit protection device for a vehicle performs basically the same operation as the conventional electric circuit protection device for a vehicle using a fuse. As shown, when the electric current constituting the wire harness is within the current range and the time range in which the smoke is generated, since this is detected and the relay device is operated, the state of each load constituting the electric circuit, The state of each electric wire constituting the wire harness, the speed of the vehicle,
There was a problem that an intelligent protection operation in consideration of the outside air temperature and the like could not be performed.

In view of the above circumstances, the present invention takes into account an operation history indicating the operation status of each load provided on a vehicle, an external factor for each load, electrical characteristic data of each load registered in advance, and the like. Then, it is possible to determine whether or not the wires constituting the wire harness are short-circuited, so that even when an inrush current flows through each load, or when the temperature of each load or each wire is high, the wire harness can be determined. For vehicles that can reliably detect when the electric wires that make up a short circuit are detected, stop supplying power to each load, reliably prevent overheating of the wire harness, and dramatically improve safety. It is intended to provide an electric circuit protection device.

[0005]

In order to achieve the above object, according to the present invention, when an abnormality occurs in an electric circuit provided in a vehicle, the abnormality is detected and the electric circuit is detected. In a vehicular electric circuit protection device for stopping and supplying power to a vehicle, a storage unit in which electric characteristic data of each component constituting an electric circuit is registered, and an operation indicating an operation status of each component. Among history data, external factor data for each of the components, and electrical characteristic data of each of the components registered in the storage unit,
An operating status determining unit that determines whether the operating status of each of the components is normal in consideration of at least two or more data; and that any one of the components is abnormal by the operating status determining unit. And a power supply control unit for stopping the power supply to the component determined to be abnormal when the determination is made.

According to a second aspect of the present invention, in the electric circuit protection device for a vehicle according to the first aspect, the operation state determination unit includes ON / OFF state data of a switch provided on an instrument panel of the vehicle, and is provided outside the vehicle. The outside air temperature information output from the provided temperature sensor, based on the vehicle speed data output from the speedometer provided in the vehicle, to access the storage unit,
The surrounding conditions of the vehicle, the running condition of the vehicle, optimal current threshold data according to the current supply condition for each of the components,
It is characterized in that any one of the optimal threshold data of the shut-off time is calculated, and based on the calculation result, it is determined whether the operation status of each component is normal.

According to a third aspect of the present invention, in the electric circuit protection device for a vehicle according to the first aspect, the storage unit and the operation state determination unit are configured by a circuit using a neural network element. It is characterized in that it is determined whether or not the operation status of each of the constituent elements is normal based on the content thus performed.

According to the first aspect of the present invention, in the first aspect, the operation status determination unit registers the operation history data indicating the operation status of each component configuring the electric circuit, the external factor data for each component, and the storage unit. It is determined whether or not the operation status of each component is normal in consideration of at least two or more data among the electrical characteristic data of each component. When it is determined that any of the above is abnormal,
The power supply control unit stops supplying power to the component determined to be abnormal. Thus, even if an inrush current flows through each component, or even if the temperature of each load or each wire is high, when each wire constituting the wire harness is short-circuited, this is reliably detected and each The power supply to the load is stopped, the overheating of the wire harness is reliably prevented, and safety is dramatically improved.

According to a second aspect of the present invention, the operation status determining unit turns on / off a switch provided on an instrument panel of the vehicle.
Off state data, outside air temperature information output from a temperature sensor provided outside the vehicle, based on vehicle speed data output from a speedometer provided in the vehicle, access the storage unit, the surrounding conditions of the vehicle, The running state of the vehicle, the optimal current threshold data according to the current supply state for each of the components, and the optimal cutoff time threshold data are calculated, and based on the calculation result, the Determine whether the operating status is normal. Thereby, the circuit using the CPU performs an intelligent short circuit determination in consideration of the outside air temperature of the area where the vehicle is present, the speed of the vehicle, the load operation state, and the like, whereby even if an inrush current flows through each component, Even when the temperature of each component and each wire is high, when each wire constituting the wire harness is short-circuited, this is reliably detected, power supply to each component is stopped, and overheating of the wire harness is prevented. Prevention and increase safety dramatically.

According to a third aspect of the present invention, a circuit constituted by a circuit using a neural network element is used as the storage section and the operating state determination section, and the circuit is constructed based on the contents learned by the neural network element. It is determined whether the operation status of each component is normal. As a result, an intelligent short-circuit determination is performed in consideration of the outside air temperature in the area where the vehicle exists, the speed of the vehicle, the load operating condition, and the like. This reduces the program load on the manufacturer side, while the inrush current flows to each load, and even when the temperature of each component or each wire is high, when each wire constituting the wire harness is short-circuited,
This is reliably detected, power supply to each component is stopped, overheating of the wire harness is reliably prevented, and safety is dramatically improved.

[0011]

FIG. 1 is a block diagram showing an embodiment of a vehicle electric circuit protection device according to the present invention.

FIG. 1 shows a vehicle electric circuit protection device 1 shown in FIG.
Are the current characteristic data of each load 8 corresponding to the outside air temperature, the current characteristic data of each load 8 corresponding to the vehicle speed, the on-duration time data of each load 8 up to the previous time, and the off-time data of the previous time for each load 8 Based on the memory circuit 2 for storing the information and the ON / OFF status data of the switches provided in the instrument panel of the vehicle, switch ON / OFF instruction data necessary for turning ON / OFF each load 8 is generated. The on / off status data, outside air temperature data output from a temperature sensor provided on the outer surface of the vehicle,
The memory circuit 2 is accessed based on vehicle speed data and the like output from a speedometer provided in the vehicle, and the optimal interruption time according to the surrounding conditions of the vehicle, the running condition of the vehicle, the current supply status to each load 8, and the like. A process of calculating threshold data, and a process of measuring a time during which each load 8 is in an on state and a time during which each load 8 is in an off state based on a current value of a drive current flowing through each load 8 And a CPU circuit 3 for performing a process of updating the ON duration time data, OFF elapsed time data, and the like stored in the memory circuit 2 based on the processing result.

Further, the vehicle electric circuit protection device 1
Fetches a current detection resistor 5 for detecting a current value of a driving current output from a plus terminal of the battery 4 having a minus terminal grounded, and a current value detected by the current detection resistor 5, and inputs the current value to the CPU circuit 3. Supply and C
When the switch-on / off instruction data output from the PU circuit 3 is an instruction to turn on the load 8, the load-on signal is generated while measuring the time during which the load-on signal is generated. Generating time is C
A driver that stops generating a load-on signal when the current value exceeds a preset current threshold even after the time indicated by the cut-off time threshold data output from the PU circuit 3 The circuit 6 and the driver circuit 6 are turned on when a load-on signal is output from the driver circuit 6. The drive current supplied through the current detection resistor 5 is supplied to each load 8 to operate each load 8. And an FET element 7.

Next, the operation of this embodiment will be described with reference to the block diagram shown in FIG. 1 and the characteristic diagram shown in FIG.

First, in a factory or the like, the relationship between the temperature of each load 8 and the inrush current is graphed based on the characteristic diagram of each load 8 prepared by each manufacturer, and the inrush current characteristics for each temperature are plotted. Is calculated based on the calculation result, and for each load 8, cut-off time threshold data corresponding to the inrush current duration of the inrush current at each temperature is tabulated, and this is stored in the memory circuit 2 as temperature characteristic data. be registered.

At this time, if the load 8 is a lamp, as shown in FIG. 2, when the temperature of the lamp is low, the time during which the rush current exceeds the current threshold becomes longer, and the lamp warms up sufficiently. In this case, since the time during which the inrush current exceeds the current threshold value becomes shorter, the temperature characteristic data set so that the cutoff time threshold value becomes shorter as the temperature becomes higher is stored in the memory circuit 2. be registered.

In addition, if the load 8 is a mounting position, for example, if the load 8 is a headlamp, as the vehicle speed increases, the characteristic curve corresponding to the outside air temperature is cooled and the temperature decreases. The current characteristic data of each load 8 indicating that the temperature decreases as the vehicle speed increases is created and registered in the memory circuit 2.

Each time the vehicle is handed over to the user side and each load 8 is turned on and off, the on / off status of a switch provided on the instrument panel of the vehicle and the output from the driver circuit 6 This is detected by the CPU circuit 3 monitoring the current value of the drive current for each load 8 to be performed, and the ON duration time data up to the previous time for each load 8 and the OFF elapsed time data up to the previous time for each load 8 Are created and registered in the memory circuit 2.

In this state, when a switch provided on the instrument panel is turned on, this is detected by the CPU circuit 3 and switch on / off instruction data necessary for turning on each load 8 is generated. The generated ON / OFF status data, outside air temperature information output from a temperature sensor provided outside the vehicle, vehicle speed data output from a speedometer provided in the vehicle, and a current value flowing through each load 8 Based on the above, the memory circuit 2 is accessed, and based on the surrounding condition of the vehicle, the running condition of the vehicle, the content of the on-duration time of each load 8 up to the previous time, the content of the elapsed time of the previous load off each load 8, etc. Is calculated and supplied to the driver circuit 6.

As a result, the load ON signal is generated by the driver circuit 6, the FET element 7 is turned on, the supply of the drive current to each load 8 is started, and the current value of the drive current is Is measured over the current threshold value output from the CPU circuit 3, and the overcurrent period obtained by this measurement operation continues for the time indicated by the cut-off time threshold data. Even though the inrush current period has ended, it is determined that the wires and the like that make up the wire harness are short-circuited, and that excessive drive current continues to flow, and based on this determination result,
The FET element 7 is turned off, and the power supply to each load 8 is stopped.

As described above, in this embodiment, the intelligent short-circuit judgment is performed in consideration of the outside air temperature in the area where the vehicle is present, the speed of the vehicle, the load operating condition, and the like. Even if current flows, or even when the temperature of each load 8 or each wire is high, when each wire constituting the wire harness is short-circuited, this is reliably detected and power supply to each load 8 is stopped. Thus, overheating of the wire harness can be reliably prevented, and safety can be dramatically improved.

Further, in this embodiment, the vehicle electric circuit protection device according to the present invention is described by taking as an example a case where the inrush current to each load 8 is not limited. However, as shown in FIG. Method (pulse width modulation control method)
For example, when the upper limit of the inrush current to each load 8 is regulated, the drive current value to each load 8 does not exceed the current threshold even if the inrush current flows to each load 8, so that the cutoff is performed. The time threshold may be shortened.

In the above-described embodiment, the factory obtains the current characteristic data of each load 8 corresponding to the outside air temperature and the current characteristic data of each load 8 corresponding to the vehicle speed, and stores the data in the memory circuit 2. Although it is registered, if it is difficult to obtain the current characteristic data of each load according to the outside air temperature, vehicle speed, etc., use a neural network element,
The neural network element may learn the current characteristic data of each load 8 according to the outside air temperature, the vehicle speed, and the like, and control each load 8 using the learning result.

Even in this case, even if an inrush current flows through each load 8 as in the above-described embodiment,
Even when the temperature of each wire is high, when each wire constituting the wire harness is short-circuited, this is reliably detected, power supply to each load 8 is stopped, and overheating of the wire harness is securely prevented. , Can greatly improve safety.

In the above-described embodiment, the cutoff time threshold data of each load 8 is used as the current characteristic data of each load 8 corresponding to the outside air temperature and the current characteristic data of each load 8 corresponding to the vehicle speed. However, current threshold data indicating the upper limit current value of the drive current may be used instead of such cutoff time threshold data.

Even in this case, even when an inrush current flows through each load 8 or when the temperature of each load 8 or each wire is high, when each wire constituting the wire harness is short-circuited, It is possible to surely detect and stop the power supply to each load 8, prevent the wire harness from being overheated reliably, and dramatically improve safety.

[0027]

As described above, according to the present invention, in the vehicle electric circuit protection device according to the first aspect, an operation history indicating the operation status of each load provided in the vehicle, an external factor for each load, By taking into account the electrical characteristic data of each load registered in advance, it is possible to determine whether or not the electric wires constituting the wire harness are short-circuited,
As a result, even if an inrush current flows through each load, or even if the temperature of each load or each wire is high, when each wire constituting the wire harness is short-circuited, this is reliably detected and the Power supply can be stopped, overheating of the wire harness can be reliably prevented, and safety can be dramatically improved.

Further, in the vehicle electric circuit protection device according to the second aspect, the circuit using the CPU makes an intelligent short-circuit determination in consideration of the outside air temperature in the area where the vehicle is present, the speed of the vehicle, the load operating condition, and the like. Therefore, even if the inrush current flows to each load, or even if the temperature of each load or each wire is high, when each wire constituting the wire harness is short-circuited, this can be reliably detected. In addition, power supply to each load is stopped, overheating of the wire harness is reliably prevented, and safety can be dramatically improved.

Further, in the vehicle electric circuit protection device according to the third aspect, the circuit using the neural network element allows the outside air temperature in the area where the vehicle exists, the speed of the vehicle, and the like.
Intelligent short circuit judgment that takes into account the load operation status can be performed, thereby reducing the program load on the manufacturer side, and even when inrush current flows through each load or when the temperature of each load or each wire is high. However, when each of the wires that make up the wire harness is short-circuited, this is reliably detected, power supply to each load is stopped, and overheating of the wire harness is reliably prevented, dramatically improving safety. be able to.

[Brief description of the drawings]

FIG. 1 is a block diagram showing one embodiment of a vehicle electric circuit protection device according to the present invention.

FIG. 2 is a graph showing an example of a temperature / rush current characteristic of a load controlled by the vehicle electric circuit protection device shown in FIG. 1;

FIG. 3 is a graph showing an example of load temperature / inrush current characteristics for explaining another embodiment of the vehicular electric circuit protection device according to the present invention.

FIG. 4 is a graph showing an example of a current cutoff characteristic of a conventionally used vehicle electric circuit protection device.

[Explanation of symbols]

 1: Vehicle electric circuit protection device 2: Memory circuit (storage unit) 3: CPU circuit (operating condition determining unit) 4: Battery 5: Current detection resistor 6: Driver circuit (operating condition determining unit, power supply control unit) 7: FET element (power supply control unit) 8: Load (electric circuit, component)

Claims (3)

[Claims] 1. An electric circuit protection device for a vehicle for detecting when an abnormality has occurred in an electric circuit provided in a vehicle and stopping and protecting power supply to the electric circuit, wherein the electric circuit is configured. A storage unit in which electrical characteristic data of each component is registered; operation history data indicating an operation status of each component; external factor data for each component; and each component registered in the storage unit An operation status determination unit that determines whether the operation status of each component is normal in consideration of at least two or more data among the electrical characteristic data of the element; A power supply control unit for stopping power supply to a component determined to be abnormal when one of the components is determined to be abnormal, and Road protection device. 2. The electric circuit protection device for a vehicle according to claim 1, wherein the operation status determination unit is configured to output ON / OFF status data of a switch provided on an instrument panel of the vehicle, and a temperature provided outside the vehicle. Based on the outside air temperature information output from the sensor and the vehicle speed data output from the speedometer provided in the vehicle,
The storage unit is accessed to calculate any one of an optimum current threshold value data and an optimum cutoff time threshold value data according to a surrounding condition of the vehicle, a running condition of the vehicle, and a current supply condition to each of the components. And determining whether or not the operation status of each of the constituent elements is normal based on the calculation result. 3. The electric circuit protection device for a vehicle according to claim 1, wherein the storage unit and the operation state determination unit are configured by a circuit using a neural network element, and the contents learned by the neural network element. A determination is made as to whether the operating status of each of the constituent elements is normal based on the following.