JP3203768B2 - Airbag control device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an airbag control device, and more particularly to an airbag control device using an electric input type collision detection sensor, which detects an initial position of the detection sensor and is suitable for verification of a collision or the like. The present invention relates to an airbag control device.

[0002]

2. Description of the Related Art In recent years, many vehicles equipped with an airbag have been known from the viewpoint of passenger protection in the event of a collision.
As an airbag activation method, there is a method using an electric input type collision sensor, and when a sensor having a contact structure is turned on , an electric current flows through a contact to a squib for igniting a gas generator, thereby It is designed to deploy an airbag. As shown in FIG. 9, a schematic configuration of this system includes a detection sensor 50 for detecting a collision.
Are provided at the front of the vehicle 51, or one each at the front and inside of the vehicle, and an arming sensor 52 for detecting a collision and preventing a malfunction on a rough terrain and the like, with a purpose of failure diagnosis and energy reserve. Controller (DE
RM) 53, a warning lamp 54, an airbag 55, and the like.

As the detection sensor 50, for example, one shown in FIG. 10 or FIGS. 11 and 12 is known.
The detection sensor 50A shown in FIG.
A conductive ball 61 is accommodated therein, and in an initial state where the device is in a normal state, it is attracted to a magnet 62 provided on the right side of FIG. When a collision occurs and the acceleration G accompanying it occurs, a force acts on the ball 61, and the force overcomes the attraction force of the magnet 62, and the ball 61 moves to the left side in the figure, and is detected by reaching the contact point 65. The sensor 50A is turned on .

Further, a detection sensor 50 shown in FIG.
B has a weight 71 provided on a disk 71 housed in a cylindrical case 70, and a shaft 73 of the disk 72.
In the initial state, the movable contact 75 is maintained in an initial state in which the movable contact 75 is not in contact with the fixed contact 76 as shown in FIG. 12 by the action of the coil spring 74. I have. When a collision occurs in the direction G in FIG. 11, the disk 71 rotates in the direction of the arrow shown in FIG.
6, and the detection sensor 50B is turned on at this time.

The arming sensor 52 is also shown in FIG.
12 is configured in advance so that it is easier to turn on than the detection sensor 50 in order to prevent malfunction of the airbag. Then, when both the arming sensor 52 and the detection sensor 50 are turned on, the airbag is deployed.

[0006]

However, FIG.
11A, when the magnetic force of the magnet is weakened, and in the detection sensor 50B of FIG. 11, when the spring force of the coil spring 74 is weakened, as shown in FIGS. The ball 61 and the movable contact 75 may be shifted from the initial position indicated by the dotted line, and when the ball 61 and the movable contact 75 are shifted to the position indicated by the solid line, the detection sensor 5
The characteristics of 0A and 50B are changed, and there is an inconvenience of causing a malfunction. This inconvenience is considered to be due to the lack of a function for detecting whether or not the vehicle is at the initial position.

[0007] By the way, since airbag control devices are concerned with safety, in the event of a collision or the like, there are devices which leave the situation at that time as data so that it can be verified later. It is assumed that the system is normal at the time of the accident, whether the warning lamp is normally lit, and whether the system is normal or abnormal, and how much acceleration G has occurred at what time from the collision. There is data for However, in the case of the electric input type collision detection sensor, since the generated acceleration G itself cannot be known as the data for estimation, the time when each sensor is turned on , for example, after the arming sensor 52 is turned on , detection sensor 50 is o
Since it is not possible to leave only, such as time to down, it is possible to guess the situation of the accident was also a disadvantage that it is difficult at a later time.

[0008]

SUMMARY OF THE INVENTION The present invention is to improve the disadvantages of the prior art, in particular, normal as possible to detect the initial position of the collision detection sensor, with abnormality can be judged, when when escaped the initial position and the sensor is turned on It is an object of the present invention to provide an airbag control device capable of easily verifying the intensity of the acceleration G or the state of occurrence of a collision from the timing of the above.

[0009]

SUMMARY OF THE INVENTION The present invention relates to a vehicle mounted on a vehicle.
Electrical input type collision detection sensor and this collision detection sensor
A controller for inputting a signal from the
Activate a given gas generator when the sensor is turned on
An airbag control device having a squib
In order to achieve the above object, in particular, the collision detection sensor,
A movable member that moves upon detecting an impact, and
A restraining means for holding the sensor at an initial position with a constant restraining force
Detecting whether the movable member is at the initial position.
Initial position detecting means for detecting the position of the movable member from the initial position.
It is installed at a fixed distance and detects contact with movable members.
And a fixed contact that outputs an ON signal.
Signal output line from initial position detection means and signal from fixed contact
Connect each of the output lines to the controller and
In the controller, the movable member has separated from the initial position.
Moving member detachment signal sometimes sent from initial position detection means
A function to output a predetermined alarm activation signal in response to a signal is provided,
The movable member detachment signal from the initial position detection means and the fixed
Based on the detection timing of the ON signal from the constant contact, the vehicle
The ability to judge both collision situations
Having a configuration .

[0010]

[Action] whether the electrical input crash detecting sensor by the initial position detecting means is normal Ru is determined by the controller. For example, when the initial position detecting means does not detect the initial position of the movable member when the ignition key is inserted , the controller outputs a predetermined alarm activation signal. Ma
And, in a normal state in which the initial position of the movable member by the initial position detecting means is detected, when the movable member has left the first <br/> phase position by the collision from the initial position detecting means
Of the movable member detachment signal and the ON signal from the fixed contact.
Vehicle collision, such as the strength of the collision , based on the exit timing
The situation can be verified.

[0011]

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

FIG. 1 shows a schematic configuration of a system of an airbag control device according to this embodiment. In this figure, an airbag control device includes two detection sensors 2 and one arming sensor 3 constituting an electric input type collision detection sensor, and an airbag gas (not shown) when these sensors 2 and 3 are turned on. The apparatus includes a squib 5 for energizing the generator, a controller 4 connected to each of the sensors 2 and 3, and an alarm lamp 6 activated by an alarm activation signal output from the controller 4.

The detection sensor 2 has, for example, a sensor structure shown in FIG. 2 or FIG. That is, the detection sensor 2 shown in FIG. 2 includes a conductive ball 11 housed in a cylindrical case 10, a fixed contact 12 that is electrically connected by the movement of the ball 11, and the ball 11. The magnet 13 for attracting and always setting the initial position on the right side in FIG. 2, the ball 11 and the magnet 1
3 and a pair of contacts 15 constituting an initial position detecting means having one end fixed to the case 10. The conductive ball 11 moves upon detecting an impact
And the magnet 13 moves the ball 11
This is a restraining means for maintaining the initial position with a predetermined restraining force.
You . Here, in the present embodiment, the state where the ball 11 contacts the contact 15 is set as the initial position, and whether the ball 11 is at the initial position is determined by applying a voltage to one contact 15 and measuring the voltage of the other contact 15. The determination can be made by detecting whether the contact 15 is on .

The sensor structure shown in FIG. 3 has a cylindrical case 20 and a movable contact 2 housed in the cylindrical case 20.
2, and a holding plate 24 having fixed contacts 23, which are electrically connected via the movable contacts 22 by rotation of the disc 21. A weight 25 is fixed to the cylindrical case 20 side of the disk 21, and a coil spring 27 for returning the disk 21 to an initial position is always wound around the rotating shaft 26. Further, the holding plate 24 is provided with a pair of contacts 28 constituting a pair of initial position detecting means at positions shifted from the fixed contacts 23 by a predetermined angle. Reference numeral 29 in FIG. 4 denotes a stopper with which the weight is engaged. This place
In this case, the disk 21 having the weight 25 and the movable contact 22 is
A movable member that moves upon detection of a strike.
The screw 27 holds the disk 21 at the initial position with a predetermined restraining force.
It is a restraining means for .

The detection sensor 2 is located at a position where the movable contact 22 abuts on a contact 28 for detecting an initial position (see FIG. 4).
Was the initial position of the sensor, the disk 21 rotates by overcoming the spring force of the coil spring 27 when caused a collision towards the G direction in FIG. 3, so as to be turned on when the movable contact 22 is in contact with the fixed contact 23 It is configured.

The arming sensor 3 can also be constituted by the sensor structure shown in FIG. 2 or FIG. However, the arming sensor 3 activates the airbag when both the arming sensor 3 and the detection sensor 2 are turned on in order to prevent malfunction due to vibration or the like caused by traveling on rough terrain. typically relatively low setting as compared to the sensor 2, i.e. o
And it has a down easily set (see FIGS. 5 and 6)

FIGS. 7 and 8 are time charts showing the amount of movement of the ball 11 of the sensor 2 and the disk 21 of the sensor 3 according to the degree of collision. FIG. 7 shows a frontal collision at a relatively high speed. The state at the time is shown. As is apparent from FIG. 7, since the sudden acceleration G is generated, there is a characteristic that the time from the initial position of the ball 11 and the disk 21 to the on-state is shortened. FIG.
Shows a state in which the vehicle collides obliquely, as is apparent from this figure, while after the low acceleration G at the beginning has occurred, a large acceleration G has passed some time occurs, ball 11, a characteristic that the time is relatively long in the oN or <br/> from the initial state disengagement of the disk 21. Therefore,
By considering also these characteristics, the relationship between the time from the initial position disengaged to the sensor on, it is possible to verify the situation at the time of collision.

Next, the operation of the present embodiment will be described.

Detection sensor 2 and arming sensor 3
However, in the case of the sensor structure shown in FIG. 2, the ball 11 is normally set at the initial position where the ball 11 is located on the rightmost side in FIG. Here, whether or not it is at the initial position can be determined by applying a voltage to one contact 15 and measuring the voltage of the other contact 15 as described above. So, for example, the ignition key
When the ball 11 is not at the initial position when the ball is inserted , a predetermined lighting display is performed by the warning lamp 6 according to a warning activation signal from the controller 4. In the case of the sensor structure shown in FIG. 3, a similar alarm is issued when the movable contact 22 is not in contact with the contact 28.

Next, a verification method when a collision accident occurs will be described.

In general, the on / off state of the sensor is not determined only by the magnitude of the acceleration G generated. In the example of FIG. 2, an air damping effect affects the acceleration G other than the acceleration G. In the example of FIG. 21 has an influence. Therefore, even if the time when the sensor is turned on is known, it is unclear how much acceleration G has occurred at that time, and since the process up to that time is involved, it is difficult to estimate the situation of the accident. Until the ball 11 and the disk 21 leave the initial positions, only the acceleration G is concerned, and neither the air damping effect nor the moment of inertia is concerned. Therefore, if the time at which the vehicle left the initial state is known, it can be understood that a certain acceleration G was generated at that time.
How much of the sensors 2 and 3 in time is that it can be seen that it has turned from the ON time after the acceleration G is generated. Therefore, the initial state escape time and the sensors 2 and 3
From both the on- time and the on- time, it is possible to estimate how much acceleration G has occurred and for how long (see FIGS. 5 and 6). At this time, the sensor characteristics shown in FIGS. 7 and 8 are considered.

Therefore, according to the embodiment of the present invention, it is determined whether or not the sensors 2 and 3 are in a normal state by detecting the initial positions of the ball 11 and the disk 21 of each of the sensors 2 and 3. When the sensors 2 and 3 are not at the initial position, a predetermined alarm is issued by a signal from the controller 4 and necessary maintenance and inspection work are performed, so that the airbag can always be maintained in a good state. This has the effect.

Also, the ball 11 of each sensor 2, 3 and the disk
By making it possible to detect the time when the vehicle 21 has left the initial position, the electric input type collision detection sensor can also grasp the situation at the time of the collision accident. Therefore, even when an accident actually occurs but the collision is not enough to deploy the airbag, it is possible to prove that the sensor was operating normally.

The structure for detecting the initial position has been described with reference to the case of a contact structure. However, the present invention is not necessarily limited to this structure, and the sensor may have a predetermined displacement corresponding to the acceleration. The design can be changed variously as long as the structure can cause the contact to be energized.

[0025]

Since the present invention is constructed and operates as described above, the present invention is applied to a collision detection sensor .
The collision detection sensor can determine whether the collision detection sensor is normal or abnormal by detecting the initial position of the movable member.
Effect but can provide an airbag control device which is capable of verifying the strength of the acceleration G, or the like occurrence of collision easily by grasping when the collision detection sensor and when escaped the initial position is turned on There is.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of an entire system of an airbag control device according to the present invention.

FIG. 2 is a sectional view showing an example of a collision detection sensor in the embodiment.

FIG. 3 is an exploded perspective view showing another example of the collision detection sensor in the embodiment.

FIG. 4 is a plan view showing a positional relationship between contacts of the sensor shown in FIG. 3;

FIG. 5 is a time chart showing a relationship between an acceleration G at the time of a collision and a movement amount of each sensor.

FIG. 6 is a time chart showing the relationship between the acceleration G at the time of another collision and the amount of movement of each sensor.

FIG. 7 is a time chart showing characteristics of a collision mode and a movement amount of each sensor.

FIG. 8 is a time chart showing characteristics of a collision mode and a movement amount of each sensor.

FIG. 9 is an explanatory diagram showing a general arrangement example of an airbag control device.

FIG. 10 is a cross-sectional view corresponding to FIG. 2, illustrating an example of a conventional collision detection sensor.

FIG. 11 is an exploded perspective view corresponding to FIG. 3, showing another example of a conventional collision detection sensor.

FIG. 12 is a plan view showing a contact position relationship of the sensor shown in FIG. 11;

FIG. 13 is a diagram for explaining a defect of each sensor having the conventional structure shown in FIG. 10;

FIG. 14 is a diagram for explaining a defect of each sensor having the conventional structure shown in FIG. 11;

[Explanation of symbols]

 2 Detection sensor constituting a collision detection sensor 3 Arming sensor constituting a collision detection sensor 4 Controller 5 Squib 6 Warning light11 Conductivity as a movable member that moves by detecting impact
Ball of 12 fixed contacts 13 Magnet as restraining means 15 Contacts as initial position detecting means 21 Disk as a movable member that moves by detecting impact 23 Fixed contacts 27 Coil spring as restraining means 28 Contact as initial position detecting means

Claims (1)

(57) [Claims] 1. An electric input type collision detection sensor mounted on a vehicle, a controller for inputting a signal from the collision detection sensor, and a predetermined gas generating device when a collision detection sensor is turned on. A squib, and a movable part that moves the collision detection sensor by detecting an impact.
The movable member and the movable member are moved to the initial position in the sensor with a predetermined restraining force.
The movable member is held in the initial position.
Initial position detecting means for detecting whether or not the
Installed at a position separated by a predetermined amount from the initial position of the member,
Fixed contact that detects ON of movable member and outputs ON signal
And a signal output line from the initial position detecting means and the fixed contact
Connect each of the signal output lines from the controller to the controller
In addition , the controller determines whether the movable member is in the initial position.
Sent from the initial position detection means when leaving
Outputs a predetermined alarm activation signal in response to a movable member detachment signal
Function, and the movable member detachment signal from the initial position detecting means and the
Based on the ON signal detection timing from the fixed contact
An airbag control device characterized in that a collision state of the vehicle can be determined .