JPS639870A - Power supply and inspection device for electric unit of automobile - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a device for supplying electric power to an electric unit installed in a motor vehicle and for checking the state of the electric power supply to this electric unit.

PRIOR ART An example of an electrical unit of this type is an actuating device for an airbag system.Normally the functioning of this electrical unit is monitored and its failure is detected by the presence of current in a connection controlling an indicating unit, e.g. a lamp. Displayed by flowing.

The electrical power supply to the electrical unit takes place via connections which are provided with protective means such as fuses.

It is also known from French Patent Publication No. 2 232 830 to signal a failure of a fuse via a display unit.

An example of such a conventional electric circuit power supply and inspection device for an automobile will be described with reference to FIG.

In FIG. 3, an actuation device 1!10 for an airbag system installed in modern motor vehicles is shown.

Since the interior of this actuating device 10 is not important to the invention, a detailed description thereof will be omitted.

The electrical unit 10 as actuator has three connections 12, 14, 16, connection 14 is designed for power supply, while connection 16 is a ground connection. The connection part 12 is an error display connection part, and a test lamp 30 is connected to this error display connection part 12 via a conductor 28.
is connected. Instead of a visual display unit, such as a test lamp, it is also possible to use an auditory display unit or to equip a speech production unit.

Positive current WX 36 is passed through fuse 34 and conductor 26.

It is connected to the supply connection 14 of the electrical unit 10.

This connection circuit is branched at a point 32 between the supply connection 14 and the fuse 34 to supply positive power to the lamp 34.

For reasons of particularly good interchangeability, each connection 12, 14, 16 has a plug connection 18°20,
It is connected to the cable via 22.

If a failure is confirmed while monitoring the electrical unit 10 for errors, the error indicator connection 12, which normally carries a positive voltage, is electrically connected to ground 24.

The resulting current, i.e. from the electric current 36 through the fuse 34, the point 32, the lamp 30 and the earth connection 12 to the earth 24, causes the test lamp 3 to
0 is lit.

Problems to be Solved by the Invention As is immediately apparent from the first drawing, in the conventional device configured as described above, even if the fuse 34 is broken, the test lamp 30 does not light up, and the user of the automobile continues to I think the airbag system is perfect, but
In reality, however, a simple failure of fuse 34 would deactivate the entire system. That is, in the case of a fuse failure, there is a problem in that a signal indicating the failure of the electrical unit, which is important for safety, is not notified to the driver.

It is an object of the present invention to notify a failure of a fuse for supplying power to an electric unit by means of a test lamp, and to prevent this even if an abnormality such as a voltage drop occurs in the supply of power to both the electric unit and the test lamp. An object of the present invention is to provide a power supply and inspection device for an electric unit of an automobile that can notify the driver of the problem.

Means for Solving the Problems In order to solve these problems, the present invention provides an electrical unit installed in the vehicle with an error indicator connection, a supply connection, and a ground connection electrically connected to the vehicle. a supply connection is provided, the supply connection is connected to the power supply via a first fuse, the first connection is connected to the error indication connection, and the first fuse separately receives the voltage from the power supply. A display unit is provided with a second Φ connection to which the voltage is applied when the first fuse fails or.

The second connection of the display unit is configured such that a closed circuit is formed between the error display connection and the earth connection when the value of the voltage to the supply connection falls below a predetermined value. To provide an electric power supply and inspection device for an electric unit of an automobile, characterized in that means for supplying electric power to electric parts such as an ignition device necessary for driving the automobile is branched from the above.

Effect: With this configuration, the display unit and the fuse of the supply connection are provided in parallel.

If an abnormality occurs in the voltage to the supply connection due to a failure of the above fuse, a closed circuit will be formed between the error display connection and the ground connection, and current will flow not only to the display unit but also to one display unit. Even when there is an abnormality in the power supply, this information is branched and transmitted to electrical parts such as the ignition system that are necessary for driving the car, and these electrical parts do not operate normally due to an abnormality in the power supply. This abnormality is recognized by the driver.

Example Embodiments of the present invention will be described in more detail based on the drawings.

1 and 2, the same components as in FIG. 3 are given the same reference numerals and will not be described again to avoid repetition.

In FIG. 1, fuse 34 is located at the common positive connection or point 32 of test lamp 30 and electrical unit 10.
It is located between the point 32 and the positive or supply connection 14 of the electrical unit 10, rather than on the positive side. Therefore, power is not supplied to the test lamp 30 via the fuse 34.

The test lamp 30 is connected on the positive side to a branch point 31, from which a branch line 40 is taken, and this branch line 40
From this, electrical power is supplied to the points necessary for the operation of the entire functional unit in which the electrical unit 10 is installed.

In this embodiment, power is supplied to the ignition system of the motor vehicle via the branch line 40. Therefore 1
The six-branch line 40, which immediately causes the vehicle to stop if the voltage drops significantly at the branch point 31, is configured to supply power to other electrical components, such as an electronic tachometer, for example, so that the driver will immediately notice the failure. Also good.

A further fuse 38 is provided between the branch point 31 and the point 32, with which the ignition system of the motor vehicle is protected.

The supply connection 14 and the earth connection 16 are connected to a control unit, shown as a relay solenoid 44, and as long as the voltage at the supply connection 14 does not fall below a predetermined lower limit value, it is connected to a control unit, depicted as a relay contact 48. The connecting wire 46 between the error display connection 12 and the ground connection 16 is open. Below this lower limit, the contact 48 is closed and the error indicator connection 12 is connected to the ground connection 16.
A conduction is formed.

The error display connection 12 is connected to ground.

Preferably, the control unit, shown here as a relay, can also be implemented using semiconductor technology.

In the embodiment shown in FIG. 2, a diode 42 is provided between the error display connection 12 and the supply connection 14 of the electrical unit IO, the 7th node side of which connects to the error display connection 12, and the cathode side of which connects the supply connection 12. It is connected to the connection part 14.

For further safety, a shorting plug 50 is provided, and this shorting plug 50 has plug contacts 18°20, 2
2 is open, the conducting wire 28 is directly connected to the ground 24. This allows the plug contact 18.
Even if 20.22 is opened, the test lamp 30 lights up.

The operation of the device shown in FIG. 1 is as follows.

When the voltage of the electrical unit 10 is normal, current flows from the power supply 36 through the point 32, the fuse 34, the conductor 26 and the plug contact 20 to the supply connection 14. When the applied voltage is normal, contacts 48 of relay 44 are opened. If a fault is identified in the electrical unit 10, the fault indicator connection 12 is connected to earth and the test lamp 30 is switched on via the plug contact 18, the conductor 28, the branch point 31 and the fuse 38, insofar as The operation of the device according to FIG. 1 is no different from the operation of the device according to FIG.

Now, if there is no current flowing through fuse 34 due to a fault in fuse 34, solenoid 44 will no longer pull up the armature and contacts 48 will be closed, causing fault indication connection 12.
is electrically connected to the ground connection 16. Therefore, the error indicator connection 12 is connected to ground 24. This causes the current to flow from point 36 to point 32. It flows through fuse 38 and bayonet contact 18 to error indicator connection 12 . As a result, the retest lamp 30 is turned on, and an error in the power supply state to the electric unit 10 is signaled.

In the embodiment according to FIG. 2, if a fault in fuse 34 prevents current from passing through this fuse 34, power supply 36 is connected to point 32. Fuse 38, branch point 31, test lamp 30
, the conductor 28 , the plug contact 18 and the diode 42 to the supply connection 14 . 1 for this circuit in parallel with the circuit by which power is supplied to the electrical unit 10.
Normally, the test lamp 30 has a high resistance, so this lamp 3
The current flowing through fuse 3 can be ignored, but the current flowing through fuse 3
4 is out of order, this circuit becomes the only energized path for the electrical unit 10. When this energizing path is formed, the test lamp 30 lights up, and an error in the power supply state of the electric unit 10 is signaled.

A fuse 38 that causes the test lamp 30 to lose its display function.
If a fault occurs, at the same time power is no longer supplied via the branch line 40 to other parts of the motor vehicle; for example, the supply of power to electrical components such as the petrol pump or the ignition system is interrupted via the branch line 40. If configured to do so, the vehicle will no longer be able to move after the fuse 38 has failed. The test lamp 30 can be provided with a suitable backup lamp, and the test lamp 30
The representation of the zero indicator as lamp 30, which can be switched to this backup lamp in the event of a failure, is by way of example only.

The device proposed according to the invention can also be used for other purposes and is not limited to the application of airbag systems.

Effects of the Invention As described above, according to the present invention, when there is an abnormality in the voltage to the electrical unit, this abnormality is not only notified on the display unit, but also when there is an abnormality in the power supply to the display unit. Even when it was.

This abnormality is reported via electrical components necessary for driving the vehicle.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing an embodiment of the power supply and inspection device for an electric unit of an automobile according to the present invention, and FIG.
The figure is a block diagram showing another embodiment of the same device, and FIG. 3 is a block diagram of a conventional power supply and inspection device for an electric unit of an automobile. 10... Operating circuit (electrical unit), 12... Connection part (error display connection part), 14... Connection part (supply connection part), 16... Connection part (earth connection part), 24.・・・
Earth, 28... Continuity (first connection part), 30...
Test lamp (display unit), 31... Branch point (second connection), 34... Fuse (first fuse), 36... Power supply, 40... Branch line (power supply means).

Claims (1)

[Scope of Claims] 1. A device for supplying power to an electric unit installed in a vehicle and for checking the state of power supply to the electric unit, the electric unit having an error display connection part and a power supply. a connection and an earth connection electrically earthed to the vehicle, the supply connection being connected to the power supply via the first fuse, the first connection connected to the error indication connection; , a display unit having a first fuse and a second connection to which a voltage from the power supply is applied separately, and when the first fuse fails or the value of the voltage to the supply connection is is configured such that a closed circuit is formed between the error display connection part and the ground connection part when the
An electric power supply and inspection device for an electric unit of an automobile, characterized in that a means for supplying electric power to electrical parts such as an ignition device necessary for driving the automobile is branched from a connection portion of the ignition device. 2. Application of voltage from the power source (36) to the connection point (31) between the branched power supply means (40) and the second connection part of the display unit (30) is applied to the second fuse (38). )
2. A device for power supply and inspection of an electrical unit of a motor vehicle according to claim 1, characterized in that the device is configured to perform the power supply and inspection via a motor vehicle. 3. Error display connection part (12) and ground connection part (16)
The formation of a closed circuit between the circuit is configured in such a way that a forward diode (42) is connected from the error indication connection (12) to the supply connection (14) of the electrical unit (10). A power supply and inspection device for an electric unit of a motor vehicle according to claim 1 or 2, characterized in that the device is characterized in that: