JP2545012B2 - Vehicle occupant protection device - Google Patents

Description

Detailed Description of the Invention

[0001]

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

[0002]

2. Description of the Related Art FIG. 9 is a block diagram of a conventional device disclosed in, for example, Japanese Unexamined Patent Publication No. 49-55031. In FIG. 9, reference numeral 801 is an acceleration sensor for detecting the degree of shock received by a car in the event of an accident. , 802 are acceleration sensor 801
An amplifier that amplifies the output signal of the amplifier 803, a threshold switch that outputs a signal when the output signal of the amplifier 802 exceeds a threshold value, 804 is an integrating circuit that integrates the output signal of the threshold switch 803, and 805 is an output signal of the integrating circuit 804. A threshold switch that outputs a signal when the threshold is exceeded, 806 is a threshold switch that outputs a signal when the output signal of the amplifier 802 exceeds the threshold, 807 is an AND circuit that logics the output signals of the threshold switches 805 and 806, and 808 is an AND circuit. 807
This is the final stage in which the ignition element 809 is started based on the output signal of the above and the air cushion 810 is inflated.

Next, the operation will be described. When the vehicle receives an impact due to an accident, the acceleration sensor 801 detects the acceleration due to this impact. This acceleration sensor 80
The detection signal of 1 is amplified by the amplifier 802 and then input to the threshold switches 803 and 806. When the input signal is larger than the threshold value, the signal output from the threshold switch 803 is integrated by the integrator 804, and when the output of the integrator 804 becomes larger than the threshold value, the threshold switch 805 produces an output. When the threshold switches 805 and 8.6 simultaneously output, the AND circuit 807 outputs.
This output signal triggers the ignition element 809 to inflate the air cushion 810.

[0004]

However, in the conventional device as described above, whether or not to inflate the air cushion as the body of the occupant protection device is determined by the magnitude of momentary damage at the time of a vehicle collision. Since it is configured to perform, the instantaneous damage is small, but the damage is sustained for a predetermined time or more, and the occupant protection device main body is surely secured in the event of a collision that will kill the occupant (hereinafter referred to as medium speed collision). There was a problem that it could not be operated.

The present invention has been made to solve the above problems, and an object of the present invention is to provide a vehicle occupant protection device capable of reliably protecting an occupant even in a medium-speed collision.

[0006]

According to a first aspect of the present invention, there is provided an occupant protection system for a vehicle, wherein an acceleration sensor for detecting a vehicle collision and an acceleration signal from the acceleration sensor are double integrated.
Means for predicting a displacement amount of an occupant due to a collision,
When the predicted signal from the means exceeds a predetermined value, the first signal is
First threshold value means for outputting and acceleration from the acceleration sensor
Input the signal, and the magnitude of the acceleration signal is the specified magnitude.
Duration does not reach predetermined criteria
When the second means for resetting the first means and the acceleration
From the acceleration signal from the sensor
The filter and the output signal from the filter.
A rectifying circuit that flows, an integrating means for the output from the rectifying circuit,
The second signal is output when the integrated output from the integrating means exceeds a predetermined value.
Second threshold value means for outputting a signal and a first threshold value from the threshold value means
The logical product with the second signal from the signal threshold means is taken and the detonator is
AND gate means for outputting a signal for driving
Be prepared .

[0007] invention passenger vehicle protection according to the 請 Motomeko 2 described, an acceleration sensor for detecting a collision of the vehicle, the acceleration sensor
Double integration of the acceleration signal from the engine
The first means for predicting the quantity and the prediction signal from the first means
First threshold value means for outputting a first signal when a predetermined value is exceeded
And input the acceleration signal from the acceleration sensor,
When the magnitude of the acceleration signal exceeds the prescribed magnitude
When the duration does not reach the predetermined standard, the first means is used.
Second means for resetting and acceleration from the acceleration sensor
Frequency signal from the frequency signal
Filter means and the square of the output signal from the filter means.
A squaring circuit, an integrating means for integrating the output from the squaring circuit,
The second signal is output when the integrated output from the integrating means exceeds a predetermined value.
From the first threshold value means for outputting a signal
AND of the first signal and the second signal from the second threshold means
And outputs a signal to drive the detonator.
It is provided with a means .

[0008]

The integrating means in the invention of claim 1 integrates the rectified output in a certain frequency band of the detection output from the acceleration sensor , that is, all positive and negative vibration components due to collision.
In the integrating means according to the second aspect of the invention , the signal component is manifested by the square of the detection output from the acceleration sensor.
To judge a collision by integrating the digitized signal
In each case, the momentary damage such as a medium collision is small, but it is possible to accurately determine a collision accident in which the damage lasts for a predetermined time or more, and to operate the passenger protection device at a good timing . occupant can be protected.

[0009]

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 a vehicle occupant protection system according to the present invention. First, the structure will be described.
Is a low-pass filter (hereinafter abbreviated as LPF) that inputs an acceleration signal from the acceleration sensor 1, 3 is a switch that opens and closes the output path of the LPF 2, and 4 is a speed that is a first incomplete integration circuit that integrates the output of the LPF 2. Computation integrator circuit, 5
Is a displacement calculation integration circuit which is a second incomplete integration circuit connected in series to the speed calculation integration circuit 4, and 6 is a first attenuator for adding a first coefficient to the detection output of the acceleration sensor 1 via the switch 3. Is a second coefficient circuit including a second attenuator for adding a second coefficient to the integrated output of the speed calculation integration circuit 4, and 8 is a displacement calculation integration circuit 5 and a first coefficient circuit 6 And an adder circuit for adding the outputs of the second coefficient circuit 7, and 9 is a threshold circuit for outputting a high level signal when the output of the adder circuit 8 exceeds a threshold value. The displacement calculation integration circuit 5, the first coefficient circuit 6, the second coefficient circuit 7, the addition circuit 8 and the threshold circuit 9 constitute a calculation means 101 for calculating the displacement estimation amount of the occupant body at the time of a collision.

Numeral 10 is a first acceleration which raises the output to a high level when the first acceleration, for example 1 G, is exceeded from a small value to a large value.
A comparison circuit 11 is a second comparison circuit that raises the output to a high level when the second acceleration, for example, 0.5 G is exceeded from a large value to a small value, and 12 is a third acceleration, for example, 4 G, a small value to a large value. The third comparison circuit 13 that raises the output to a high level when the output exceeds the
A fourth comparison circuit 14 that raises the output to a high level when G is exceeded from a small value to a large value, is a first comparison circuit 10
When the output of the third comparator circuit 12 is at the high level, the timer time is activated, and the first timer that outputs the high level signal while the first timer time T1 elapses When the second timer time T2 elapses, the second timer 16 outputs a high level signal while the second timer time T2 elapses.
A NOR gate for inputting the output signal of the timer 15, 17 is an OR gate for inputting the output signals of the second comparison circuit 11 and NOR gate 16, and 18 is set by the output of the first comparison circuit 10 and the output of the second comparison circuit 11 , Or
A set / reset flip-flop (hereinafter abbreviated as RSFF) that is reset by any of the outputs of the NOR gate 16 closes the switch 3 by the output of the RSFF 18, and the integrating circuit for speed calculation 4, the integrating circuit for displacement calculation 5, and Reset other integration circuits. Reference numeral 19 is an RSFF which is set by the output from the fourth comparison circuit 13, makes the output high level, and is reset by the output of the NOR gate 16.

Here, the first to fourth comparison circuits 10 to 1
3, first timer 14, second timer 15, NOR gate 1
By 6, OR gate 17, RSFF 18 and 19,
A control circuit 102 that controls the operation of the arithmetic means 101 and detects a collision is configured.

Reference numeral 20 denotes a low-pass filter (hereinafter abbreviated as LPF) which has a cut-off frequency different from that of the low-pass filter 2 and which inputs an acceleration signal from the acceleration sensor 1, and 21 subtracts outputs of the LPF 2 and the LPF 20. ,
Subtraction circuit that outputs only a signal in a certain frequency band, 2
2 is a full-wave rectifier circuit that rectifies the output of the subtraction circuit 21, 23 is an integration circuit that integrates the output of the full-wave rectification circuit 22 and is reset by the output of the FF 18, and 24 is high when the output of the integration circuit 23 is equal to or greater than a threshold value. A threshold circuit for outputting a level signal, and 25 is a set / reset flip-flop (hereinafter abbreviated as FF) which is set by the high level signal of the threshold circuit 24 and reset by the high level signal of the NOR gate 16.

Here, the LPF 20, the subtraction circuit 21,
The full-wave rectification circuit 22, the integration circuit 23, and the threshold circuit 24 form a collision detection circuit 103.

Reference numeral 26 is an OR gate which receives the outputs of the FF 19 and FF 25, and 27 is the activation of the detonator 28 when a high level signal is supplied from the threshold circuit 9 of the arithmetic means 101 and the OR gate 26 of the collision detection circuit 103. It is an AND gate that outputs a signal.

Next, the operation will be described. Various accelerations act on the acceleration sensor 1 as the vehicle travels. Since the output C of the FF 18 is at a low level when the vehicle is traveling at a constant speed, the integration switch 3
Is in the off state, and both the first and second incomplete integration circuits 4 and 5 are in the reset state.

In this state, as shown in FIG.
When there is a light collision of G waveform (a) that converges toward 0G after attaching two peaks (for example, <4G), the integration switch 3 is turned on when the G waveform (a) exceeds 1G. When turned on, the timer function of the first timer 14 is operated for a predetermined time. However, within this predetermined time, for example, 1
Since the G waveform that exceeds 0 G is not generated, the FF 18 is reset after the elapse of a predetermined time, and the integration switch 3, the first and second incomplete integration circuits 4 and 5 are reset.

Further, when a collision of G waveform (b) occurs, which has one peak (<4 G) and then changes greatly toward 0 G and again toward 10 G, this G waveform b is 1 G.
The first timer 14 starts to operate when the time exceeds. Then, since the second timer 15 starts to operate before the time-up of the first timer 14, the timer time of the first timer 14 is further extended by the same time. However, since a G waveform that exceeds 10 G does not occur even within this extended time, the integration switch 3 is turned off by resetting the FF 18, and the detonator 28 is not activated in the case of the light collision.

Next, one peak (<4 G) is set, the first timer 14 is activated, and the first timer 14 is activated within 10 hours.
When a G waveform C exceeding G is generated, the output of the FF 19 becomes high level by the fourth comparison circuit 13, and the gate of the AND gate 27 is opened via the OR gate 26.
When the output of the threshold circuit 9 becomes high level, the detonator 28 is activated.

Also, after one peak (<4G) is added, it goes to 0G, then increases again to 10G, and becomes 10G.
A case will be described in which a serious collision accident such as that shown in the G waveform D that exceeds the above occurs. Within the operation time T1 of the first timer 14, or the second time following the operation of the first timer 14.
When the G waveform exceeds 10 G within the operation time T2 of the timer 15, the RSFF 19 is set at this point. As a result, the output of the RSFF 19 becomes high level (see H in FIG. 2). As a result, the output of the OR gate 26 also becomes high level (see M in FIG. 2).

The AND gate 27 is opened when the OR gate 26 outputs a high level signal, that is, when the G waveform D exceeds 10G. In the AND gate 27, when the AND logic is established between the output of the threshold circuit 9 of the calculation means 101 (see O in FIG. 2) and the output of the OR gate 26, at the time when the high level signal of the threshold circuit 9 is output. The detonator 28 is activated.

Next, the case of a serious collision accident in which the momentary damage is small but the occupant is killed after the damage lasts for a predetermined time or more will be described. In this case, the proportion of high frequency components included in the acceleration signal output from the acceleration sensor 1 is necessarily large.

In the above serious collision accident, the G waveform may not exceed 10G. Therefore, by outputting only a signal in a certain frequency band included in the acceleration signal output from the acceleration sensor 1, it is determined that the serious collision accident has occurred, the AND gate 27 is opened, and the output signal of the threshold circuit 9 is output. The detonator 28 is operated based on (corresponding to the estimated displacement of the occupant's body).

Therefore, in this embodiment, the acceleration sensor 1
The LPF2, the LPF 20, and the subtraction circuit 21 extract only a signal in a certain frequency band included in the acceleration signal output from the full-wave rectification circuit 22. The full-wave rectifier circuit 22 full-wave rectifies the output of the subtraction circuit 21 shown in FIG. 3A and outputs it as a signal shown in FIG. The output signal of the full-wave rectification circuit 22 is output to the integration circuit 23 and accumulated.

The integrating circuit 23 outputs the output signal indicated by I in FIG. 3 to the threshold circuit 24. When the output signal of the integrating circuit 23 reaches the threshold value Vt set in the threshold circuit 24, the threshold circuit 24 outputs the high-level signal indicated by r in FIG. 3 even if the G waveform does not exceed 10G. And R
The SFF 25 is set, and the serious collision accident described above is determined.

Therefore, the OR gate 26 outputs a high level signal even in a situation where the RSFF 19 is not set. As a result, the AND gate 27 is in a state in which the gate is opened even without receiving a large impact of 10 G or more. Therefore, the high-level output signal output from the threshold circuit 9 causes the above-described serious collision accident. Therefore, the detonator 28 can be appropriately operated to protect the occupant.

In this embodiment, the subtraction circuit 2
Although the output of each of LPF2 and 20 is subtracted at 1,
As shown in FIG. 4, a new LPF 50 for inputting the output of the G sensor 1 in place of the output of the LPF 2 is provided, and both L
Set different frequency bands of PF20 and 50,
It goes without saying that the respective outputs may be input to the subtraction circuit 21. LPF
It is needless to say that 20 may be deleted and the respective outputs of the LPFs 2 and 50 may be input to the subtraction circuit 21. In that case, it is necessary to set the frequency band of the LPF 20 to have the LPF 2. is there.

FIG. 5 is a block diagram showing a second embodiment of the present invention. In this embodiment, a band pass filter (hereinafter, referred to as a "pass filter" for extracting only a signal in a constant frequency band, which is present in place of the LPF 20 and the subtraction circuit 21 in the first embodiment shown in FIG.
29), which is abbreviated as BPF) and has the same other configurations and operational effects as those of the first embodiment described above, and therefore redundant description will be omitted. The full-wave rectification circuit 22 in FIG. 5 may be replaced by a squaring circuit.

FIG. 6 is a block diagram showing a third embodiment of the present invention. This embodiment uses a high-pass filter (hereinafter abbreviated as HPF) 30 for extracting high frequency components included in an acceleration signal, instead of the LPF 20 and the subtraction circuit 21 in the first embodiment shown in FIG. The other configurations and operational effects are the same as those of the first embodiment, and thus redundant description will be omitted.

FIG. 7 is a block diagram showing an embodiment according to the invention described in claim 2. In FIG. 7, 31 is LPF2
Is a high-pass filter (hereinafter abbreviated as HPF) having a cutoff frequency higher than the cutoff frequency. This HPF
An acceleration signal output from the acceleration sensor 1 is input to 31 and a high frequency component included in this acceleration signal is extracted and output. Reference numeral 32 denotes a square circuit, which has a square characteristic in the transfer characteristic between the input voltage and the output voltage, and outputs the input signal in a full-wave rectified state. The squaring circuit 3
Needless to say, when an odd power circuit is used instead of 2, the output is rectified and output. 33 integrates the output of the squaring circuit 32,
An integrator circuit that is reset by the output signal of 18.
Reference numeral 34 denotes a threshold circuit which outputs a high level signal when the output of the integrating circuit 33 becomes equal to or higher than the threshold. 35 is a threshold circuit 3
4 is set by a high level signal, and the NOR gate 1
The RSFF is reset by a high level signal of 6. Here, the HPF 31, the squaring circuit 32, the integrating circuit 33, and the threshold circuit 34 constitute a collision detecting circuit 103. 36 is an OR gate to which the output signals of the RSFF 19 and the RSFF 35 are input. Although the G sensor 1 output is supplied to the HPF 31 in the embodiment shown in FIG. 7, the LPF 2 output may be supplied to the HPF 31. Further, the squaring circuit 32 may be replaced by a full-wave rectification circuit.

The operation of this embodiment will be described below with reference to the timing chart shown in FIG. Now, although the momentary damage is small, when a serious collision accident that causes death of the occupant occurs after the damage lasts for a predetermined time or longer, the proportion of high frequency components included in the acceleration signal output from the acceleration sensor 1 is , Will inevitably grow.

In the above-mentioned serious collision accident, the G waveform may not exceed 10G. Therefore, the acceleration sensor 1
The AND gate 27 is opened by identifying the magnitude of the high frequency component contained in the acceleration signal output by the vehicle occupant, and the occupant protection device main body is based on the output signal of the threshold circuit 9 (corresponding to the estimated displacement of the occupant's body). Operate.

Therefore, in this embodiment, the acceleration sensor 1
The high frequency component contained in the acceleration signal output by the HPF3
It is extracted by 1 and supplied to the squaring circuit 32. The squaring circuit 32 processes the output of the HPF 31 shown in FIG. 8A based on the square characteristic, and outputs it as a signal shown in FIG. The output signal of the squaring circuit 32 is output to the integrating circuit 33 and accumulated.

In this way, when the output signal of the squaring circuit 32 is integrated, the output signal of the integrating circuit 33 changes gently as shown by I in FIG. As a result, the acceleration sensor 1
When the acceleration signal, which is the output of, is simply full-wave rectified and then integrated by the integrator circuit, the output signal of the integrator circuit is, as shown by the dotted line in FIG. There is a risk that the threshold voltage V _t will be reached and the high level output signal shown in FIG. However, in this embodiment, since the output signal of the integrating circuit 33 is gentle, it is possible to output a high level output signal at an appropriate time T and activate the detonator 28 at an appropriate timing to inflate the airbag.

[0034]

According to the invention described in claim 1, the collision of the vehicle
Threshold when the rectified output of the constant frequency band of the detection output from the acceleration sensor for detecting the collision is integrated by the integrating means, the integral output of the integrating means <br/> becomes more preset value
I tried to drive the detonator of the passenger protection device from the value means
However, the instantaneous damage such as a medium collision is small, but it can provide an effective means to protect the occupant from a serious collision accident in which the damage lasts for a predetermined time or more and causes the occupant to die.
It

[0035] According to the invention of 請 Motomeko 2, wherein the collision of the vehicle
Constant frequency with detection output from the acceleration sensor that detects
The threshold value is obtained when the square output of several bands is integrated by the integrator , and the integrated output of this integrator exceeds a preset value.
From the means to drive the detonator of the occupant protection device
Therefore, the S / N ratio of the acceleration signal due to the collision can be improved
Momentary damage such as a medium collision continues for more than a predetermined time
The collision judgment of a serious collision that could result in death of the occupants.
The degree can be improved .

[Brief description of drawings]

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

FIG. 2 is a signal waveform diagram of each part in the first embodiment.

FIG. 3 is a signal waveform diagram of the collision detection circuit in the first embodiment.

FIG. 4 is a block diagram of another embodiment of the first embodiment.

FIG. 5 is a block diagram of a second embodiment according to the present invention.

FIG. 6 is a block diagram of a third embodiment according to the present invention.

FIG. 7 is a block diagram of an embodiment showing a vehicle occupant protection device according to a second aspect of the invention.

8 is a signal waveform diagram of the collision detection circuit in the embodiment of FIG.

FIG. 9 is a block diagram of a conventional vehicle occupant protection device.

[Explanation of symbols]

 1 Acceleration Sensor 22 Full Wave Rectifier Circuit 23 Integrating Circuit 24 Threshold Circuit 28 Detonator 32 Square Circuit (Power Circuit)

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Satoru Matsumori 2-1910 Nisshin-cho, Omiya-shi, Saitama, Kansei Co., Ltd. (72) Inventor Katsuji Oneda 2-1910 Nisshin-cho, Omiya-shi, Saitama Kansei Co., Ltd. (56) References JP-A-47-36438 (JP, A) JP-A-3-253441 (JP, A) International publication 88/146 (WO, A) International publication 90/9298 (WO, A)

Claims (2)

(57) [Claims] 1. An acceleration sensor for detecting a collision of a vehicle ,
The acceleration signal from the acceleration sensor is double integrated to
The first means for predicting the displacement amount of the passenger and the first means
A first signal that outputs a first signal when the predicted signal exceeds a predetermined value
1 threshold value means and input acceleration signal from the acceleration sensor
However, the magnitude of the acceleration signal exceeds the specified magnitude.
When the duration of the
Second means for resetting one means and the acceleration sensor
Extract the signal component in the specified frequency band from these acceleration signals
Rectifying the output signal from the filter means and the filter means
Rectifier circuit and an integrator that integrates the output from the rectifier circuit
And when the integrated output from the integrating means exceeds a predetermined value
Second threshold value means for outputting a second signal, and the first threshold value means
And a second signal from the second threshold means
And the signal for driving the detonator is output.
An occupant protection device for a vehicle, comprising: an AND gate means . 2. An acceleration sensor for detecting a collision of a vehicle ,
The acceleration signal from the acceleration sensor is double integrated to
The first means for predicting the displacement amount of the passenger and the first means
A first signal that outputs a first signal when the predicted signal exceeds a predetermined value
1 threshold value means and input acceleration signal from the acceleration sensor
However, the magnitude of the acceleration signal exceeds the specified magnitude.
When the duration of the
Second means for resetting one means and the acceleration sensor
Extract the signal component in the specified frequency band from these acceleration signals
And the output signal from the filter means
Square circuit and an integrator that integrates the output from the square circuit
And when the integrated output from the integrating means exceeds a predetermined value
Second threshold value means for outputting a second signal, and the first threshold value means
Of the first signal from and the second signal from the second threshold means
An AND that takes the logical product and outputs the signal to drive the detonator
An occupant protection device for a vehicle, comprising: