JP2795329B2 - Vehicle occupant protection system - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an occupant protection system for protecting an occupant in the event of a vehicle collision.

[0002]

2. Description of the Related Art As a conventional vehicle occupant protection device, for example, there is one as shown in FIG. In the drawing, reference numeral 1 denotes an acceleration sensor as a vehicle body vibration sensor made of, for example, a piezoelectric ceramic having a preamplifier and a filter;
Reference numeral 2 denotes an integration circuit to which an output signal from the acceleration sensor 1 is supplied. This integration circuit 2 performs an integration operation when the input is equal to or higher than a predetermined threshold. Reference numerals 3a and 3b denote threshold switches to which the integration signal integrated by the integration circuit 2 is supplied. One threshold switch 3a is set so that the integration signal reaches a threshold during a normal collision, and the other threshold switch 3b is larger. It is set so that the integrated signal reaches a threshold value at the time of collision. 4
Is an AND gate in which the output terminal of the threshold switch 3a is connected to one input terminal, and the other input terminal of the AND gate 4 is connected to the output terminal of a time circuit 5 described later. An OR gate 6 has an output terminal of the AND gate 4 connected to one input terminal. The other input terminal of the OR gate 6 is connected to an output terminal of the threshold switch 3b. Reference numeral 7 denotes an AND gate in which the output terminal of the OR gate 6 is connected to one input terminal, and the output terminal of the AND gate 7 is a driving circuit 8
It is connected to the. Reference numeral 9 denotes an occupant protection device main body driven by the drive circuit 8.

[0005] Reference numeral 5 denotes a time circuit having a threshold circuit 10 set to a threshold lower than the threshold of the threshold switch 3a. The output of the integration circuit 2 is added to the threshold circuit 10. The output terminal of the threshold circuit 10 has three timing elements 11a, 11b, 1
1c is connected to the trigger input terminal. 1st timed element 1
The output terminal 1a is connected to the set input terminal of the first bistable trigger circuit 12, and the output signal of the first bistable trigger circuit 12 is inverted and supplied to the other input terminal of the AND gate 7. The output terminal of the second timed element 11b is connected to the set input of the second bistable trigger circuit 13, and the output signal of the second bistable trigger circuit 13 is inverted and supplied to the other input terminal of the AND gate 4. . The output terminal of the third timed element 11c is connected to the reset input terminals of the first and second bistable trigger circuits 12, 13.

Next, the operation will be described. When the low threshold of the threshold circuit 10 is exceeded in the time circuit 5, all the timed elements 11a, 11b, 11c are triggered. The output terminal of the bistable trigger circuit 12 has a short first signal of, for example, about 2 ms.
A time output signal appears. Since the output signal of the bistable trigger circuit 12 is inverted and supplied to the AND gate 7,
During the first time, the drive circuit 8 is blocked, and thus the operation of the occupant protection device body 9 is blocked. After the elapse of this short first time, the output signal of the bistable trigger circuit 12 disappears, so that a high-level signal is applied to the other input terminal of the AND gate 7. That is, if the signal is the threshold switch 3
When the signal is supplied to the OR gate 6 via the line b, the AND gate 7 becomes conductive.

Next, triggered by the timing element 11b, the bistable trigger circuit 13 generates a zero signal. Since the zero signal is inverted and supplied to the other input terminal of the AND gate 4, the AND gate 4 generates a signal sent from the threshold switch 3a. After the lapse of the first time, the timed element 1
If the integrated signal exceeds the threshold value of the threshold value switch 3a during the elapse of the second time of, for example, about 30 ms defined by 1b, the occupant protection device main body 9 operates. Threshold switch 3a
Is relatively low, but is selected to be large enough to reach at the time of collision.

If the threshold value of the threshold switch 3a is not exceeded after the lapse of the second time, the AND gate 4 is blocked. In this case, the operation of the occupant protection device main body 9 can be performed only by the threshold switch 3b having a high threshold. After a lapse of, for example, 200 ms, determined by the third timing element 11c, both bistable trigger circuits 12, 13 are reset, and the main circuit is returned to the starting position.

[0007]

However, in such a conventional vehicle occupant protection device, whether or not to operate the occupant protection device body 9 in consideration of the amount of movement of the vehicle body and the degree of impact. Is determined using a determination circuit based on a complicated logic, so that the determination of a serious accident tends to be inaccurate.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and an object of the present invention is to provide an occupant protection system for a vehicle in which a circuit configuration is simplified to make an accurate determination.

[0009]

Means for Solving the Problems According to the invention of claim 1
The vehicle occupant protection device uses a vibration sensor
Integrates the output signal of
Determines whether the amount of movement of the measured object has reached a predetermined size.
Judge, and output the first signal when it is judged that it has reached
Moving state determining means and an output signal from the vibration sensor
Judge whether it is a serious collision based on
If a judgment is made, reset the integrated value of the moving status judgment means.
Output a second signal when it is determined that a serious collision has occurred.
Collision determining means, and a first signal from the moving state determining means.
When the signal and the second signal from the collision determination means are input
And gate means for outputting a trigger signal.
Vehicle occupant protection device based on a trigger signal from
It activates the body .

[0010] A vehicle occupant protection according to the second aspect of the invention.
The device integrates the output signal from the vibration sensor installed on the vehicle body
Movement of the measured object due to collision based on the integrated value
Judging the situation and preventing the measured object from colliding with the vehicle body
A first timing signal for outputting a first timing signal for stopping
Weighting means based on an output signal from the vibration sensor.
Determines whether there is a major collision or not,
Prevents the measured object from hitting the vehicle body
Outputs the second timing signal and it is not a serious collision
If it is determined, the integrated value of the first timing means is reset.
Second timing means for setting, and the first and second timers
First and second timing signals from both the imaging means
A gate means for outputting a trigger signal when is supplied.
The vehicle occupant protection device body by the trigger signal.
It works .

[0011]

The vehicle occupant protection device according to the first aspect of the present invention uses the output signal from the vibration sensor to determine the movement status.
And the collision determination means in parallel, and the logical product of the results
In the event of a serious collision
If it is determined that there is no
Therefore, it is necessary to reset the integral
The result of the judgment by the movement status judgment means, especially
Judgment of a large collision after a small collision
The occupant protection device itself
Can be made .

According to a second aspect of the present invention, in the vehicle occupant protection device, the output signal from the vibration sensor is supplied to the first timing.
And the second timing means determine in parallel.
Configured to AND the result and the first timing
If it is determined that the collision is not a serious collision,
Is configured to reset the integral value by
The accuracy of the judgment result by the first timing means can be improved,
Actually, the occupant protection device main body can be operated .

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail with reference to the drawings. FIG. 1 is a block diagram showing an embodiment of the present invention.
Reference numerals 1 and 9 denote the same acceleration sensor and occupant protection device body as in FIG. First, the configuration will be described.
A switch 15 for determining whether or not to perform the integration operation of the acceleration signal a (t) is output when the acceleration signal a (t) exceeds the first acceleration, for example, 1 G, from a small value to a large value. The first comparison circuit for setting to the high level, 16 is the second comparison circuit
The second comparator circuit 17 which sets the output to a high level when the acceleration signal a (t) exceeds the acceleration, for example, 0.5 G, from a large value to a small value, and 17 outputs a third acceleration, for example, 10 G, to the acceleration signal a (t) ) Is a third comparison circuit that sets the output to a high level when the value of () exceeds from a small value to a large value.

Reference numeral 18 denotes a set / reset flip-flop (hereinafter referred to as FF) which turns the output Q high when the output of the first comparison circuit 15 becomes high.
, 19 is a speed calculation integration circuit formed of an incomplete integration circuit, 20 is a displacement calculation integration circuit formed of an incomplete integration circuit connected in series to the speed calculation integration circuit 19, 21
Is a first coefficient circuit composed of an attenuator for adding a first coefficient to the detection output of the acceleration sensor 1 via the integration switch 14;
Is a second coefficient circuit composed of an attenuator for adding a second coefficient to the integration output of the speed calculation integration circuit 19; 23 is a displacement calculation integration circuit 20, a first coefficient circuit 21 and a second coefficient circuit 22
This is an addition circuit for adding the output of the control circuit. The switch 14, the speed calculation integration circuit 19, and the displacement calculation integration circuit 2
0, the first coefficient circuit 21, the second coefficient circuit 22, and the addition circuit 23 constitute a movement amount determination circuit of the measured object.

For example, when an acceleration of 10 G or more is applied, a set / reset flip-flop (hereinafter, abbreviated as FF) which outputs an output Q to a high level based on an output from the third comparison circuit 17 and outputs it to the AND gate 30 is provided. , 2
5 activates a timer time after the output of the first comparison circuit 15 becomes high level, and a predetermined time T ₁ (for example, 10 m
s), the first timer 26, which receives the high-level signal from the first timer 25 and the second comparison circuit 16, outputs the high-level output to the OR gate 27.
When the high-level output is supplied from the AND gate 26 or a second timer 28, which will be described later, the OR gate 27 changes the output to a high level, and
Reset. A timer 28 operates after the output of the first comparison circuit 15 becomes high level, and keeps the low level output for a predetermined time T ₂ (for example, 70 ms), and becomes high level when the timer time ends. FF1
This is a second timer for resetting 8, 24. Reference numeral 31 denotes the comparison circuits 15, 16, 17, FFs 18, 24, and timer 2
5, 28, an AND gate 26 and an OR gate 27. 29 is an adder 23
Is a threshold circuit that supplies a high-level output signal to one input of the AND gate 30 when the output signal of the AND gate 30 exceeds a threshold. Reference numeral 37 denotes a moving state determining circuit including the moving amount determining circuit and the threshold circuit 29. FIG.
6 is a timing chart showing a signal at point J.

Next, the operation will be described. Various accelerations act on the acceleration sensor 1 as the vehicle travels. Now, when the vehicle is traveling at a constant speed, the output Q of the FF 18 is at a low level, so that the switch 14 is turned off and the two integrating circuits 19, 20 are provided.
Is in a reset state. Here, a certain impact is applied to the vehicle, and an acceleration signal a (t) of, for example, 1 G or more that acts on the vehicle in the front-back direction is detected by the acceleration sensor 1, and the output of the first comparison circuit 15 (FIG. 2A) is at a high level. , The output Q of the FF 18 (FIG. 2G) becomes high level,
The switch 14 is turned on, and this is connected to two integrating circuits 1
9 and 20 are supplied to the reset terminals R to start respective integration operations and operate the coefficient circuits 21 and 22. Therefore, a signal (FIG. 2J) indicating the moving amount of the measured object such as the occupant's head is obtained from the adding circuit 23.

When the output signal from the first comparison circuit 15 goes high, the output of the first timer 25 goes high for a predetermined time T ₁ as shown in FIG. Thereafter, when the acceleration signal a (t) falls below the acceleration of 0.5 G, for example, and the output of the second comparison circuit 16 becomes a high level as shown in FIG. D, it is determined that the vehicle is traveling on a rough road. Then, the output of the AND gate 26 (FIG. 2H) becomes high level, the FF 18 is reset via the OR gate 27, the switch 14 is turned off, and the integration operation is stopped. Therefore, the occupant protection device main body 9 does not operate.

If there is a collision that gives a serious impact to the human body, the acceleration signal a (t) becomes larger than 1 G, for example, and the output signal from the first comparison circuit 15 becomes high level. At the same time, when the third comparison circuit 17 changes from low level to high level, the output Q of the FF 24 is latched at high level, and one input of the AND gate 30 is set to high level. On the other hand, the output J
Exceeds the threshold value of the threshold circuit 29, the other input of the AND gate 30 is set to a high level, the occupant protection device body 9 such as an airbag or a preloader is activated, and the head of the occupant is hit against a handle attached to the vehicle body. To prevent injury.

Next, another embodiment of the collision judging circuit 31 will be described with reference to FIG. FIG. 3 shows the collision determination circuit 31 of FIG.
2 shows a second timing circuit 38 in which the timer is reduced by one. In the present embodiment, the movement status determination circuit 37 shown in FIG. 1 is configured as a first timing circuit 37. In the figure, the same parts as those in FIG. In the figure, reference numeral 32 denotes a first one-shot multivibrator operated by a timer 25;
Reference numeral 3 denotes a second one-shot multivibrator operated by the timer 25. The pulse width of the second one-shot multivibrator 33 is longer than the pulse width of the first one-shot multivibrator 32, and returns after a lapse of the pulse width. 34 is a first AND gate for ANDing the output from the first comparison circuit 15 and the output from the second one-shot multivibrator 33, and 35 is the third comparison circuit 1
A second AND gate 36 which ANDs 7 with the second one-shot multivibrator 33 is a third AND gate 36 which ANDs the output of the second comparison circuit 16 and the output of the first one-shot multivibrator 32. When the output of the third AND gate 36 goes high, the FFs 18, 24
And each of the timers 25 is reset.

Next, the operation will be described. First and second one-shot multivibrators 3 based on power-on
Outputs 2 and 33 are at a high level. Then, the second comparison circuit 16 outputs an acceleration signal a of 0.5 G or more, for example.
Upon detecting (t), the second comparison circuit 16 supplies a low-level output to the third AND gate 36 to release the reset of the FFs 18, 24 and the timer 25. Thereafter, as shown in FIG. 4A, in the case of a light collision in which the acceleration signal a (t) detected by the acceleration sensor 1 does not reach 10 G, for example, the high level output from the first comparison circuit 15 and the second one The AND with the high level signal from the shot multivibrator 33 is taken by the first AND gate 34 and the FF is taken.
18 is set, and the switch 14 is turned on by the output Q.

However, since the output of the third comparison circuit 17 remains at the low level, the output of the AND gate 30 does not go to the high level, so that the output of the first one-shot multivibrator 32 after the timer 25 operates for a predetermined time. Is temporarily inverted as shown in FIG. 17H, the output of the third AND gate 36 is set to a low level, and the FFs 18, 24 and the timer 2
Reset 5 Since the output of the acceleration sensor 1 does not exceed the reference value of the third comparison circuit 17 during that time, the FF 24
Hold the low level state and supply it to the AND gate 30. Therefore, the occupant protection device main body 9 does not operate regardless of the output value of the human body movement amount determination circuit.

The acceleration signal a (t) detected by the acceleration sensor 1 is, for example, 10 as shown in FIG.
When a frontal collision of G or more occurs, as shown in FIG. 5E, the FF 18 is set by ANDing the high-level output of the first comparison circuit 15 and the high-level signal from the second one-shot multivibrator 33, The switch 14 is turned on. Therefore, the speed calculation integration circuit 19 calculates the acceleration signal a
(T) is integrated, and the integration output is used as a displacement operation integration circuit 20
Integrate by

The integration output of the displacement operation integration circuit 20, the output of the first coefficient circuit 21, and the output of the second coefficient circuit 22 are added by an addition circuit 23, and the added output is added to a threshold circuit 2.
9 to one input of an AND gate 30.
The FF 24 is set by ANDing the high-level signal from the third comparison circuit 17 and the high-level signal from the second one-shot multivibrator 33, and the high-level output signal from the FF 24 is output to the other of the AND gate 30. Feed to the input. For this reason, the AND gate 30 activates the occupant protection device body 9 such as an airbag by the AND output.

Further, when the acceleration signal a (t) detected by the acceleration sensor 1 is, for example, from a light collision of less than 10 G to a frontal collision of 10 G or more as shown in FIG. 6A, in the first light collision, The FF 18 is set by ANDing the high-level output of the first comparison circuit 15 and the high-level signal from the second one-shot multivibrator 33, and the switch Q is turned on by the output Q. Then, the movement amount determination circuit is operated to calculate the acceleration signal a (t). However, since the collision is a light collision, the operation result does not exceed the threshold value of the threshold circuit 29, and the output of the third comparison circuit 17 remains at the low level. Therefore, the occupant protection device main body 9 does not operate.

Thereafter, the acceleration signal a (t) is set to, for example, 10
When G exceeds G, the output of the first comparison circuit 15 goes high, the output of the first AND gate 34 goes high, and the FF 18 outputs a high-level signal.
Is turned on, the output of the third comparison circuit 17 is at a high level, and the output of the second AND gate 35 is also at a high level. As a result, the FF 24 outputs a high-level signal, the output of the FF 24 is supplied to the other input of the AND gate 30, and the output of the AND gate 30 causes the occupant protection device 9
(See FIG. 6).

In the case of, for example, an oblique collision as shown in FIG. 7A, the magnitude of the acceleration signal a (t) from the acceleration sensor 1 is detected in the same manner as in the above-described operation, and the occupant protection device main body 9 is moved. Each timing circuit 3 determines whether to operate or not.
It is controlled by 7, 38.

[0027]

As described above, according to the first aspect of the present invention,
Lever, its configuration, the output signal from the vibration sensor, the movement
Judgment is made in parallel by the situation judgment means and the collision judgment means,
It is configured to take the logical product of the results, and
If it is determined that the collision is not a serious collision, the moving situation judgment means
Reset the integration value at
The accuracy of the determination result by the disconnecting means can be enhanced, and the effect that the occupant protection device main body can be reliably operated can be obtained.

According to the second aspect of the present invention, the vehicle occupant protection device outputs the output signal from the vibration sensor to the first timing.
And the second timing means make a parallel determination.
And the first timing
If it is determined that the collision is not a serious collision,
Since the integral value in the timing means is reset,
As a result of the decision made by the first timing means, a particularly small collision
After a collision, the accuracy of the decision
The occupant protection system can be operated reliably.
The effect is obtained .

[Brief description of the drawings]

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

FIG. 2 is a timing chart showing the operation of the device.

FIG. 3 is a block diagram showing a collision determination circuit of a vehicle occupant protection device according to another embodiment of the present invention.

FIG. 4 is a timing chart showing the operation of the device.

FIG. 5 is a timing chart showing another operation of the device.

FIG. 6 is a timing chart showing another operation of the device.

FIG. 7 is a timing chart showing another operation of the apparatus.

FIG. 8 is a block diagram showing a conventional vehicle occupant protection device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Acceleration sensor (vibration sensor) 9 Occupant protection device main body 30 AND gate (gate circuit) 31 Collision judgment circuit 37 Moving state judgment circuit, 1st timing circuit 38 2nd timing circuit

 ──────────────────────────────────────────────────続 き Continuation of the front page (72) Inventor Satoru Matsumori 2-1910 Nisshin-cho, Omiya-shi, Saitama Kansai Co., Ltd. 253441 (JP, A) WO 90/9298 (WO, A1)

Claims (2)

(57) [Claims] 1. An output signal from a vibration sensor (1) provided on a vehicle body is integrated, and it is determined based on the integrated value whether or not a movement amount of an object to be measured accompanying a collision has reached a predetermined size. Then, when it is determined that the vehicle has arrived, it is determined whether or not a serious collision has occurred based on the output signal from the vibration sensor (1) and the movement status determining means (37) that outputs the l-th signal. If it is determined that there is no collision, the integrated value of the moving state determination means (37) is reset. If it is determined that the collision is serious, collision determination means (31) that outputs a second signal;
And a gate means (30) for outputting a trigger signal when the second signal from the first signal and the collision judging means (31) from the moving state determining means (37) is input, the vibration
The output signal from the motion sensor is transmitted to the above-mentioned moving condition determining means (3).
7) and the collision judging means (31) judge in parallel,
Vehicle occupant protection apparatus, characterized in that allowed to operate the occupant protection apparatus body for a vehicle (9) based on the trigger signal from the gate means (30). 2. The method according to claim 1, further comprising: integrating an output signal from a vibration sensor provided on the vehicle body; determining a moving state of the measured object accompanying the collision based on the integrated value; First timing means (37) for outputting a first timing signal for preventing a collision, and the vibration sensor (1)
It is determined whether or not the collision is a serious collision based on the output signal from the vehicle. If the collision is determined to be serious, a second timing signal for preventing the measured object from being hit against the vehicle body is output. If it is determined that there is no second value, the second value for resetting the integral value of the first timing means (37)
A timing means (31, 38 ); and a gate means for outputting a trigger signal when the first and second timing signals are supplied from both the first and second timing means (37 ), (31, 38 ). 30), and the vibration sensor
The output signal from the first timing means (37)
It is determined in parallel with the second timing means (31, 38).
The vehicle occupant protection device is characterized in that the vehicle occupant protection device body (9) is activated by a trigger signal from the gate means (30) .