JPH04208662A - Device for driver's/passenger's security in vehicle - Google Patents

Abstract

PURPOSE:To reduce the work for adjusting a judgment circuit by judging level of acceleration signal, and by stopping operation of a driver's security device body through judging that the signal is due to a rough road or light collision if the detected level does not continue over preset duration. CONSTITUTION:While a vehicle is running, if any impacts act on the vehicle, and acceleration signals in the front-and-back-ward direction, for example, of 1G or more is detected by an acceleration sensor 1, and output from a first comparing circuit 15 reaches high level, then output Q from a FF18 reaches the high level, and a switch 14 is turned on, and integral control action of two incomplete integral circuits 19 and 20 is started. At that time, if output from a first timer 25 is in the high level continuously for a preset time T1 and, after that, the acceleration becomes, for example, 0.5G or less, and output from a second comparing circuit 16 reaches the high level, it is judged that the vehicle is running on a rough road. And, output from an AND gate reaches the high level and makes the FF18 reset through an OR gate 27 for switching off the switch 14, and stops the operation of the driver's security device body 9.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a vehicle occupant protection device for protecting an occupant during a vehicle collision.

[Prior Art] As a conventional vehicle occupant protection device, there is one shown in FIG. 9, for example. In the figure, 1 is an acceleration sensor such as a piezoelectric ceramic having a preamplifier and a filter, and 2 is an integrating circuit to which an output signal from the acceleration sensor 1 is supplied. Performs integral action. 3a and 3b are dark value switches to which the integral signal integrated by the integrating circuit 2 is supplied; one dark value switch 3a is set to reach the dark value in a normal collision, and the other dark value switch 3b is set to reach the dark value in the event of a normal collision. It is set to reach the darkness value in the event of a major collision. Reference numeral 4 designates an AND gate having one input end connected to the output end of the dark value switch 3a, and the other input end of this AND gate 4 being connected to the output end of a time circuit 5 to be described later. 6 is and gate 4
is an OR gate whose output terminal is connected to one input terminal, and the output terminal of the dark value switch 3b is connected to the other input terminal of this OR gate 6. 7 is 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 connected to the drive circuit 8. Reference numeral 9 denotes a safety device which is the main body of the occupant protection device driven by the drive circuit 8.

Thus, the time circuit 5 has a threshold circuit 10 set to a dark value lower than the dark value of the dark value switch 3a. This dark value circuit 10 is triggered by the output of the integrating circuit 2. The output end of the dark value circuit 10 has three time elements 11a, llb,
It is connected to the trigger input terminal of ie. The output terminal of the first timer 11a is connected to the set input terminal of the first bistable trigger circuit I2, 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. Ru. The output terminal of the second timer 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 of the third timer 11c is connected to the reset inputs of the second and third bistable trigger circuits 12.13.

Next, the operation will be explained.

When the low threshold of the dark value circuit 10 is exceeded in the time circuit 5, all time elements 11a, llb, llc are triggered. Therefore, a short-time output signal of, for example, about 2 ms appears at the output end of the bistable trigger circuits 12 and 13. The output signal of this bistable trigger circuit 12 is inverted and fed to the AND gate 7, so that for a short period of time the drive circuit 8 is blocked and thus the activation of the safety device 9 is blocked. After this short first time has elapsed, the bistable trigger circuit 12.13
Since the output signal disappears, a high level signal is applied to the other input terminals of AND gates 4 and 7.

That is, when a signal is supplied to the OR gate 6 via the dark value circuit 3, the AND gate 7 becomes conductive.

In addition, when the dark value of the threshold circuit 10 is exceeded, the time limit block 11b is also triggered, so it is a bistable trigger time! 13 generates a zero signal. This zero signal is inverted and fed to the other input of AND gate 4, so that AND gate 4 generates a signal that is sent via threshold switch 3a. After the first time period has elapsed, if the darkness value of the darkness value switch 3a is exceeded during the elapse of a second time period of, for example, about 30 m5 determined by the timer 11b, the safety device 9 is activated.

The darkness value of the darkness value switch 3a is relatively low, but is selected to be large enough to reach at the time of a collision. The safety device 9 can be activated by the second dark value switch 3b during the second time period, as long as a relatively large threshold value defined in the dark value switch 3b is exceeded.

After the second time has elapsed, the darkness value of the darkness value switch 3a is not exceeded,
Therefore, when the threshold value of the dark value switch 3b is not reached, the AND gate 4 is blocked. In this case, safety device I9
can only be activated by a dark value switch 3b with a high threshold value. When the time period, for example 200 m5, defined by the third timing element 11c has elapsed, both bistable trigger circuits 12,13 are reset and the main circuit is again in its starting position.

[Problem to be solved by the invention]

However, in such a conventional vehicle occupant protection device, since a 2 ms mask is used to prevent malfunction, there is a risk that the safety device 9 may not operate in the event of a high-speed collision. In addition, if a major collision occurs after a minor collision, each of the timer elements 11a to 11c would be activated, causing the timing of the activation of the safety device 9 to deviate, which could result in injury to the occupants. Furthermore, since the decision as to whether or not to operate the safety device 9 is made by a decision circuit based on logic, there is a problem in that the decision criteria of the decision circuit such as the dark value circuit must be adjusted frequently, making the adjustment work complicated. there were.

The present invention has been made to solve the above-mentioned problems, and an object of the present invention is to provide a vehicle occupant protection device that reduces the number of threshold circuits and reduces the adjustment work of the determination circuit.

[Means to solve the problem]

The vehicle occupant protection device according to the present invention includes an acceleration sensor that detects an acceleration signal, and a judgment circuit that activates or deactivates the occupant protection device main body depending on the generation status of the acceleration signal detected by the acceleration sensor. However, this judgment circuit includes a level judgment circuit that judges the level of the acceleration signal;
When the level detected by this level detection circuit does not last for a predetermined time or longer, or when a large acceleration such as 10G is not reached, it is determined that the road is rough or a minor collision has occurred, and the operation of the occupant protection device is stopped. It is something that has the means.

[For production]

The vehicle occupant protection device according to the present invention operates the occupant protection device main body according to the generation status of the acceleration signal, determines the level of the acceleration signal, and when the level does not last for a predetermined time or more, the vehicle occupant protection device main body operates. It is designed to stop the operation.

〔Example〕

The present invention will be explained below based on the drawings.

FIG. 1 is a block diagram showing one embodiment of the present invention.
In the figure, the same or equivalent components as in FIG. 9 are given the same reference numerals, and redundant explanation will be omitted.

First, to explain the configuration, 15 is a first comparator circuit that outputs a high level when the acceleration exceeds, for example, lG from a small value to a large value, and 16 is a first comparison circuit that outputs a high level when the acceleration exceeds, for example, 0.5G from a large value to a small value. 17 is a third comparator circuit that outputs a high level output when the acceleration exceeds lOG from a small value to a large value; these comparison circuits 15 and 16
17 constitutes a level determination circuit. 18 is a set/reset flip-flop (hereinafter referred to as
19 is a set/reset flip-flop (hereinafter abbreviated as FF) that sets the output Q to high level when the output of the third comparison circuit 17 becomes high level.
．． 20 is a first timer which starts the timer after the output of the first comparison circuit 15 becomes high level, and continues the output at high level for a predetermined time T, ms (for example, 10m5); 21 is a first comparison circuit; 15 and an AND gate that outputs a high level when a high level signal is supplied from the second comparison circuit 16; 22 is an OR gate to which the output of the AND gate 21 is supplied; When a high level signal is supplied from the second timer 23, the output is set to a high level and the FF 18 is reset. 23 starts the timer time after the output of the first comparison circuit 15 becomes high level, and runs for a predetermined time T2.
ms (for example, 70m5), and when the output continues at a high level and the timer time ends, FF1B.

19, this second timer 23
The output of is connected to the reset terminal of FF19. The FFs 1B and 19, the timer 20.23, the AND gate 21, and the OR gate 22 constitute an operation stopping means, and the level determining circuit and the operation stopping means constitute a judgment circuit 24.

Reference numeral 25 denotes a switch for determining whether or not to integrate the acceleration signal from the acceleration sensor 1, and this switch 25 is closed when the output of the FF 1B becomes high level. Reference numeral 26 indicates a velocity calculation integration circuit which is a first incomplete integration circuit; 27 indicates a displacement calculation integration circuit which is a second incomplete integration circuit connected in series with the velocity calculation integration circuit 26; a first coefficient circuit consisting of a first attenuator that adds a first coefficient to the detection output; 29 a second coefficient circuit consisting of a second attenuator that adds a second coefficient to the integral output of the speed calculation integrating circuit 26;
0 is an addition circuit that adds the outputs from the displacement calculation integration circuit 27, the first coefficient circuit 28, and the second coefficient circuit 29, which includes the switch 25, the speed calculation integration circuit 26, the displacement calculation integration circuit 27, and the first coefficient. On the second circuit, the second coefficient circuit 29 and the addition circuit 30 constitute a human body movement amount determination circuit.

31 is a dark value circuit that supplies an output to one input of the AND gate 32 when the output signal of the adder circuit 30 exceeds a threshold value. Further, the other input of the AND gate 32 has an FF
It is supplied when the output of No. 19 becomes high level.

Next, the operation will be explained.

As the vehicle travels, various acceleration signals are sent to the acceleration sensor 1.
It acts on Now, when the vehicle is running at a constant speed, if, for example, 16 or more acceleration signals acting in the longitudinal direction of the vehicle are detected by the acceleration sensor 1 and the output of the first comparison circuit 15 becomes high level, the FF1B The output Q becomes a high level, turns on the switch 25, and rapidly discharges the electric charge charged in the integration capacitors of the two incomplete integration circuits 26 and 27.

Thereafter, when the acceleration signal shown in FIG. 2 is detected by the acceleration sensor 1 and the output signal from the first comparison circuit 15 becomes high level as shown in FIG. As shown in FIG. B, a predetermined time T,
It remains at a high level for more than ms. Also, at the same time, the second
When the output of the comparison circuit 16 becomes high level as shown in the figure, it is determined that the vehicle is traveling on a rough road, and the output of the AND gate 21 becomes high level, and the FF 1B is reset via the OR gate 22. The switch 25 is turned off to stop the 11-integral operation. Therefore, the safety device 9 does not operate.

Furthermore, even if the output signal from the first comparison circuit 15 causes the output of the second timer 23 to go high as shown in FIG. does not reach a high level, so after continuing for more than a predetermined time T, ms, it is determined that it is a minor collision and the FF is activated.
19 is reset, the FF 18 is also reset via the OR gate 22, the switch 25 is turned off, and the integral operation is stopped. Therefore, the safety device 9 does not operate.

Next, the acceleration signal shown in FIG. 3 is detected by the acceleration sensor 1, and as shown in FIG. When the output from the 3-comparison circuit 17 becomes high level, the FFs 18 and 19 are set. Therefore, the FF 18 turns on the switch 25, so the speed calculation and integration circuit 26 integrates the acceleration detection signal, and then the integral output of the speed calculation and integration circuit 26 is integrated by the displacement calculation and integration circuit 27. Then, the integral output of the displacement calculation integration circuit 27, the output of the first coefficient circuit 28, and the second coefficient circuit 29
The adder circuit 30 adds the outputs of the outputs 1 and 30, and the added output is supplied to one input of the AND gate 32 via the dark value circuit 31. Further, the FF 19 supplies a high level output signal to the other input of the AND gate 32. For this reason, the AND gate 32 supplies an AND output as shown in FIG.

Next, another embodiment of the determination circuit 24 will be described based on FIG.

FIG. 4 shows a judgment circuit obtained by subtracting one timer from the judgment circuit shown in FIG. 1, and the same parts in the figure are given the same reference numerals and redundant explanation will be omitted. In the figure, 33 is timer 2
The first one-shot operated by 0, 34 is a timer 20.
The pulse width of the second one shot 34 is longer than the pulse width of the first one shot 33, and the pulse width returns after the elapse of this pulse width. 35
is the output from the first comparison circuit 15 and the second one shot 34
36 is a second AND gate that ANDs the output of the second comparison circuit 17 and the second one shot 34; 37 is the AND gate of the output of the second comparison circuit 16 and the first one shot 33; A third AND gate performs AND with the output, and when the output of the third AND gate 37 becomes high level, it resets each of the FFLs 8 and 19 and the timer 20.

The first step is based on the power being turned on. 2nd one shot 33.3
The output of No. 4 is at a high level. When the second comparator circuit 16 detects an acceleration signal of, for example, 0.5 G or more, the second comparator circuit 16 supplies a high level output to the third AND gate 37 to
to be reset. Thereafter, as shown in FIG. 5A, if the acceleration signal detected by the acceleration sensor 1 is less than 100, for example, a light collision, the high level output from the first comparator circuit 15 and the high level output from the second one shot 34 are output. AND with the signal is taken by the first AND gate 35 and F
Set F1B and turn on switch 25. However, since the third comparison circuit 17 remains at low level,
The output of the AND gate 32 does not become high level, so the second one shot 3 is output after the timer 20 has operated for a predetermined time.
The output of the first AND gate 35 is temporarily inverted as shown in FIG. After that, in order for the second one shot 34 to return after a predetermined period of time, the FF 1B again outputs a high level signal to turn on the switch 25 and the AND gate 32
It is determined whether the amount of human body movement is greater than a threshold value and is supplied to one of the inputs. However, since the output from the FF 19 is not supplied to the other input of the AND gate 32, the safety device 9 does not operate.

If the acceleration signal detected by the acceleration sensor 1 is 100 or more, for example, as shown in FIG. 6A, the first comparison circuit 15
The high level output from the second one shot 34 is ANDed with the high level signal from the second one shot 34, FF1B is set, and the switch 25 is turned on. For this reason, the speed calculation integration circuit 2
6 integrates the acceleration detection signal, and then integrates the integral output of the velocity calculation and integration circuit 26 by the displacement calculation and integration circuit 27. Then, the integral output of the displacement calculation integration circuit 27 and the first
The output of the coefficient circuit 28 and the output of the second coefficient circuit 29 are added by an adder circuit 30, and the added output is supplied to one input of an AND gate 32 via a threshold circuit 31. Further, the high level signal of the third comparison circuit 17 and the high level signal from the second one shot 34 are ANDed and the FF1
9 is set, and the high level output signal from this FF 19 is supplied to the other input of the AND gate 32. Therefore, the AND gate 32 supplies the AND output to the safety device 9 to activate the main body of the occupant protection device such as the air hack.

Further, if the acceleration signal detected by the acceleration sensor 1 goes from a light collision of less than 100 to a head-on collision of more than IOC as shown in FIG. The high level output and the high level signal from the second one shot 34 are ANDed and F
F1B is set and the switch 25 is turned on. Then, the human body movement amount judgment circuit is operated to calculate the acceleration signal from the acceleration sensor 1. However, since it is a light collision, the calculation result does not exceed the dark value of the dark value circuit 31, and the output of the third comparison circuit 17 remains at a low level, so the output of the AND gate 32 is at a high level. Therefore, the safety device 9 will not operate. After that, when the acceleration signal exceeds, for example, IOC, the output of the first comparison circuit 15 becomes high level, the output of the first AND gate 35 becomes high level, and the FF 18 outputs a high level signal and turns on the switch 25. let

On the other hand, when the FF 19 outputs a high level signal, the output from the FF 19 is supplied to the other input of the AND gate 32, and the output of the AND gate 32 activates the safety device 9 (see FIG. 7).

In addition, even in the case of an acceleration signal caused by an oblique collision with a telephone pole, as shown in FIG. A judgment circuit controls whether or not.

〔Effect of the invention〕

As described above, according to the present invention, the configuration includes an acceleration sensor that detects an acceleration signal, and a main body of the occupant protection device that is activated or deactivated depending on the generation status of the acceleration signal detected by the acceleration sensor. and a determination circuit that determines the level of the acceleration signal, and if the level detected by the level determination circuit does not persist for a predetermined period of time or more, it determines that the road is rough or a minor collision has occurred, and the determination circuit determines the level of the acceleration signal. Since the vehicle occupant protection device is characterized by having an operation stop means for stopping the operation of the protection device body, it is possible to reduce the number of dark value circuits and reduce the adjustment work of the judgment circuit, and it is also possible to prevent not only high-speed collisions but also light collisions. Even if a drastic collision occurs, the occupant protection device main body can be reliably activated at an appropriate timing.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing a vehicle occupant protection device according to an embodiment of the present invention, FIGS. 2 and 3 are waveform diagrams of various parts explaining the operation of FIG. 1, and FIG. 4 is a block diagram showing a vehicle occupant protection device according to an embodiment of the present invention. A block diagram showing another embodiment of the vehicle occupant protection device, FIGS. 5 to 8 are waveform diagrams of various parts explaining the operation of FIG. 4, and FIG. 9 shows an example of the conventional vehicle occupant protection device. FIG. 1... Acceleration sensor, 9... Occupant protection device main body, 1
5.16.17...Level judgment circuit, 18.24...
・Set/reset flip-flop, 25.28...
・Timer, 26...and gate, 27...or gate.

Claims (1)

[Claims] A vehicle occupant protection device comprising: an acceleration sensor that detects an acceleration signal (1); and a judgment circuit that activates or deactivates an occupant protection device main body (9) depending on the generation status of the acceleration signal detected by the acceleration sensor. In the above, the judgment circuit includes a level judgment circuit (15, 16, 17) that judges the level of the acceleration signal, and if the level detected by this level judgment circuit does not last for a predetermined time or more, it is judged that the road is rough or a minor collision has occurred. Operation stop means (18, 24, 25, 28, 26, 2
7) A vehicle occupant protection device comprising: