JP2003040077A - Air bag operating device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an air bag operating device reducible in cost by reducing the number of sensors for detecting impact without lowering accuracy in detecting the impact of a vehicle. SOLUTION: In this air bag operating device, a first sensor for detecting impact applied in the longitudinal direction of the vehicle, a second sensor for detecting impact applied in the lateral direction of the vehicle, an ignition map provided with a first threshold value for developing an air bag at the occurrence of an asymmetric collision and a second threshold value for developing the air bag at the occurrence of a symmetric collision, and an asymmetric collision determining region map for determining an asymmetric collision from the magnitude of impact detection output of the second sensor, are integrally provided in a control circuit for controlling the development of the air bag provided at the vehicle. In the case of determining the asymmetric collision from the impact detection output of the second sensor and the asymmetric collision determining region map, when the impact detection output of the first sensor is less than the second threshold value but not less than the first threshold value, the air bag is developed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an airbag operating device, and more particularly, to reducing the number of sensors for detecting an impact without lowering the accuracy of impact detection of a vehicle and simplifying a calculation method for determining an impact to a computer. The present invention relates to an airbag operating device capable of reducing the capacity of the device and reducing the cost while maintaining the performance.

[0002]

2. Description of the Related Art Conventionally, a seat belt is generally used as an occupant protection device for protecting the safety of an occupant in the event of a vehicle collision, but in recent years, a vehicle employing an airbag as an occupant protection auxiliary device (SRS) has been developed. It is increasing. In the past, SRS airbags were often installed only in front of the driver's seat and passenger's seat, but recently, SRS side airbags built into the left and right doors of automobiles and above the left and right windows. Some cars have SRS curtain shield airbags built into the car body.

By the way, in frontal collisions, which are frequent in vehicle collisions, there are symmetrical collision modes called frontal collisions in which the left and right front surfaces of the vehicle evenly collide with each other, and the left and right frontal surfaces of the vehicle collide unevenly (offset collision). ), Or the car collides obliquely (oblique collision). When these frontal collisions are detected, the front airbag is inflated by gas (hereinafter referred to as deployment) to protect the driver or the passenger in the passenger seat. Therefore, it is important to control the ignition of the squib which deploys the airbag by discriminating whether the frontal collision of the vehicle is a symmetrical collision or a non-systematic collision. The deployment control of the side airbag and the curtain shield airbag described above is performed by a control device installed in each of the left and right B pillars and C pillars of the automobile.

As described above, in order to determine whether the frontal collision of the vehicle is a symmetrical collision type or an asymmetrical collision type, one impact detection sensor is not enough. The reason for this is that the value of the impact force output from the impact detection sensor is small in the asymmetrical collision mode, and the airbag is deployed in the asymmetrical collision mode at the threshold value set to deploy the airbag in the symmetrical collision mode. Because you cannot do it. Therefore,
In a conventional occupant protection device, a mechanical front right sensor and a left front sensor that individually detect front and rear impacts on the left side and the right side of the vehicle are provided at the front of the vehicle. In many cases, an electronic type center sensor that detects an impact in the front-rear direction is provided.

However, in the occupant protection system of this embodiment, one expensive mechanical front sensor is required on each side of the front portion of the automobile, and an electronic center sensor is required in the central portion of the automobile. Therefore, there is a problem in that the cost of the device increases.

Therefore, in Japanese Patent Laid-Open No. 2000-71929, instead of the two mechanical left and right front sensors provided in the front part of the automobile, two electronic sensors are built in on the left and right sides of the dashboard of the automobile. A start-up control device for an occupant protection device of this type has been proposed.

Further, in Japanese Unexamined Patent Publication No. 9-132108, calculation values are obtained by predetermined calculations for accelerations obtained from acceleration sensors in the front-rear direction and the left-right direction.
Is the sum fα of the projection components of the vector based on these two calculated values for the preset angle α calculated and comparing the sum fα of the projection components with the threshold value set in advance for the direction α to deploy the airbag? An activation control device for an occupant protection device that determines whether or not it is disclosed.

[0008]

However, even in the activation control device for the occupant protection device proposed in Japanese Patent Laid-Open No. 2000-71929, sensors for detecting front and rear impacts on the left side portion and the right side portion of the automobile are Even though it is an electronic type, it requires two, so the cost can be reduced compared to the case of using two mechanical front sensors, but the total number of sensors used is three, which reduces wiring costs. Considering it, it did not lead to such a big cost reduction.

Further, the activation control device for an occupant protection device proposed in Japanese Unexamined Patent Publication No. 9-132108 requires the calculation of a trigonometric function, which causes a problem that the calculation becomes complicated.

Therefore, according to the present invention, the number of sensors for detecting the impact is reduced and the calculation method for determining the impact is simplified to reduce the capacity of the computer without reducing the accuracy of the impact detection of the vehicle. It is an object of the present invention to provide an airbag actuating device capable of reducing the cost while maintaining the above.

[0011]

Various forms of the airbag operating apparatus of the present invention for achieving the above object will be described below.

The first embodiment includes a first sensor for detecting the magnitude of the impact applied to the front and rear direction of the vehicle, and a second sensor for detecting the magnitude of the impact applied to the left and right of the vehicle. In an airbag operating device, which is integrally provided in a control circuit for controlling deployment of an airbag provided in a vehicle, and the control circuit controls deployment of the airbag based on impact detection outputs of these two sensors, The control circuit is the first
An ignition map including a first threshold value for deploying the airbag at the time of an asymmetrical collision and a second threshold value for deploying the airbag at the time of a symmetrical system collision, according to the magnitude of the impact detection output of the sensor An asymmetrical collision determination area map for determining an asymmetrical collision from the magnitude of the impact detection output of the first sensor and the second sensor is provided, and the control circuit determines an asymmetrical collision from the asymmetrical collision determination area map. In this case, when the impact detection output of the first sensor is equal to or greater than the first threshold value, the airbag is inflated.

According to a second aspect, in the airbag operating apparatus of the first aspect, the control circuit is based on the calculated value of the impact detection output of the first sensor and the calculated value of the impact detection output of the second sensor. It is characterized in that it operates.

According to a third aspect, in the airbag operating apparatus of the second aspect, the calculated value of the impact detection output of the first sensor is the total integrated value of the impact detection outputs of the first sensor,
The calculated value of the impact detection output of the sensor is a section integral value of the impact detection output of the second sensor within a predetermined time.

According to a fourth mode, in the airbag operating apparatus of any one of the first to third modes, the control circuit further determines a bad road traveling mode based on the impact detection output of at least the second sensor. The area determination map of No. 1 is provided, and the collision mode and the rough road traveling mode are distinguished from this area determination map.

According to a fifth aspect, in the airbag operating apparatus of the first aspect, weighting means for weighting the second sensor output value is further provided, and the first sensor output and the output of this weighting means. Thus, the control circuit discriminates a collision mode between a symmetrical collision and an asymmetrical collision of the vehicle, and controls the deployment of the airbag.

In the airbag actuating device of the present invention having the above-mentioned configuration, since the two collision detection sensors arranged close to each other can surely discriminate between the symmetrical collision and the asymmetrical collision, the number of sensors is reduced. In addition to being able to reduce the number of wiring harnesses, wiring harnesses are not required, and the cost can be reduced without deteriorating the performance. In addition, it is possible to discriminate between a bad road traveling mode and an asymmetrical collision mode. Furthermore, by weighting the impact force in the left-right direction and combining this with the impact force in the front-rear direction, it is possible to realize an airbag actuation device that can be applied to a wide variety of vehicles.

[0018]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below in detail based on specific examples with reference to the accompanying drawings.

FIG. 1 (a) shows an airbag operating device 10 according to an embodiment of the present invention, which is provided in a vehicle.
2 and its drive circuit 11 are shown. As shown in FIG. 1B, the airbag device 12 includes a passenger seat SRS airbag 12A and a driver seat SRS airbag 1 of a vehicle 20.
Although there are 2D, SRS side door airbag 12S, etc., they are collectively referred to as an airbag device 12 in FIG. 1 (a). In addition to the squib 13 which is an ignition device, the airbag device 12 includes a gas generating agent that is ignited by the squib 13, an airbag that is deployed by the generated gas, and the like, but these are not shown. The airbag operating device 10 of this embodiment is arranged in the center of the automobile 20.

The airbag operating device 10 includes a vehicle 20.
A front-rear sensor (first sensor) 1 that detects the intensity of front-to-back impact on the vehicle, and a left-right sensor (second sensor) 2 that detects the intensity of left-to-right impact on the vehicle 20.
And are integrally provided in the main body. In this embodiment, the front-rear sensor 1 and the left-right sensor 2 are electronic sensors. The front-rear sensor 1 measures the deceleration applied to the vehicle 20 in the front-rear direction and outputs the measurement signal, and the left-right sensor 2 measures the vehicle. The acceleration applied to the left-right direction with respect to 20 is measured and the measurement signal is output.

In addition to the front-rear sensor 1 and the left-right sensor 2, an input / output interface circuit (I / O) 3, an activation control circuit (CPU) 4, a program, a map, and the like stored in the airbag operating device 10 are read out. Dedicated memory (ROM)
5 and a read / write memory (RAM) 6 for temporarily storing data and the like, which are interconnected by a bus 7. Further, the outputs of the front-rear sensor 1 and the left-right sensor 2 are I
Input to / O3. Also, I / O3
When an ignition signal is input to the drive circuit 11 from the squib 1 in which the drive circuit 11 is built in the airbag device 12,
3 is energized, the squib 13 is ignited, and the airbag is deployed.

The internal structure of the front-rear sensor 1 and the left-right sensor 2 will be described.

FIG. 2 (a) shows an example of a detailed configuration of the front-back sensor 1. The front-rear sensor 1 includes a front-rear sensor element 31, an input / output interface circuit (I / O) 33, a control circuit (CPU) 34, a read-only memory (ROM) 35, and a read / write memory that are mutually connected by a bus 37. There is a (RAM) 36. The CPU 34 controls the I / O 33 and the RAM 36 according to the program stored in the ROM 35. The measured value of the front-back impact applied to the vehicle, which is detected by the front-rear sensor element 31 and is input to the I / O 33, is stored in the RAM 36, and
Output from the I / O 33 to the I / O 3 of the airbag operating device 10.

FIG. 2B shows an example of a detailed configuration of the left and right sensors 2. The left and right sensor 2 includes a left and right sensor element 42, an input / output interface circuit (I / O) 43, a control circuit (CPU) 44, a read-only memory (ROM) 45, and a read / write memory that are mutually connected by a bus 47. There is a (RAM) 46. The CPU 44 controls the I / O 43 and the RAM 46 according to the program stored in the ROM 45. The measured value of the lateral impact applied to the vehicle, which is detected by the left and right sensor elements 42 and is input to the I / O 43, is stored in the RAM 46, and
Output from the I / O 43 to the I / O 3 of the airbag operating device 10.

When the signals from the front and rear sensors 1 and the left and right sensors 2 are input to the I / O 3 in this way, the I / O 3 sends the signals to the CPU 4. The CPU 4 performs a predetermined calculation on the signals from the front and rear sensors 1 and the signals from the left and right sensors 2 according to a program stored in the ROM 5, and makes a comparison judgment with a threshold stored in the ROM 5. The RAM 28 stores the data obtained from the signals from the front and rear sensors 1 and the left and right sensors 2, the calculation result of the CPU 4 based on the data, the comparison result, and the like.

That is, the CPU 4 of the airbag operating device 10
Is a predetermined threshold value that is a signal indicating the level of impact severity obtained from the front-rear sensor 1 based on the detection result of the symmetrical or asymmetrical collision form obtained from the left and right sensors 2 or the rough road traveling form. In comparison with the above, it functions as an activation control circuit that controls the activation of the airbag device 12.

The operation of the front-rear sensor 1, the left-right sensor 2, and the CPU 4 in the difference of vehicle collision will be described.
When the deceleration G (t) applied to the vehicle 20 in the front-rear direction is measured by the front-rear sensor element 31 shown in FIG. 2A, the front-rear sensor 1 uses the measured value G (t) as a measurement signal. / O33 through the airbag operating device 1 shown in FIG.
0 to CPU4. CPU4 is front and rear sensor element 3
A predetermined calculation is performed on the measured value G (t) output from 1
The calculation value VY is calculated by performing the calculation according to the following formulas 1 and 2.
1, VX1 is calculated. The calculated value VY1 is a section integrated value of the longitudinal acceleration, and the calculated value VX1 is a total integrated value of the longitudinal acceleration.

[0028]

[Equation 1]

[0029]

[Equation 2]

In Equation 1, the interval integration is performed for a certain defined interval of 10 ms, but this 10 ms is merely an example. Further, in the mathematical expression 2, the total integrated value obtained by integrating from 0 ms to a certain time t is obtained.

The values determined by the calculated values VY1 and VX1 are compared with the determination map stored in the ROM 5 as shown in FIG. In this determination map, the horizontal axis represents the calculated value VX1 and the vertical axis represents the calculated value VY1, and the low threshold value LS (first threshold value) and the high threshold value HS (second threshold value). And with. Here, the low threshold value LS is set to a value larger than the magnitude of the shock applied to the automobile 20 when a shock in the front-rear direction that is not enough to activate the airbag device 12 is applied due to the asymmetrical collision mode. There is. Also, a high threshold HS
Of the impact applied to the vehicle 20 in the front-back direction to the extent that the airbag device 12 is not activated due to the symmetric collision mode, or the impact applied to the vehicle 20 when the vehicle 20 is traveling on a rough road. It is set to a value larger than the size.

Therefore, the CPU of the airbag operating device 10
4 is a high threshold value HS, a low threshold value LS, and a calculated value VY1,
The calculated value VY is compared with the value determined by VX1.
If the value defined by 1, VX1 exceeds the high threshold value HS, a high shock signal is output to I / O3. If the value determined by the calculated values VY1 and VX1 does not exceed the high threshold value HS but exceeds the low threshold value LS, a middle shock signal is output to the I / O3. If the value determined by the calculated values VY1 and VX1 does not exceed the low threshold value LS, the CPU 4 does not output a signal to the I / O 3.

On the other hand, the left and right sensor elements 42 of the left and right sensor 2
Is the acceleration G applied to the vehicle 20 in the left-right direction.
(T) 'is measured at any time, and the measured value is output to the I / O 43. In the left / right sensor 2, when the deceleration G (t) ′ applied to the vehicle 20 in the left / right direction is measured by the left / right sensor element 42, the measured value G (t) ′ is I / O 43 through the I / O 43 as a measurement signal. Input to O3. CPU4
Is a calculation value VY2 obtained by performing a predetermined calculation on the measured value G (t) 'output from the left and right sensor elements 42 input to the I / O3, that is, I / O.
The measured value G (t) output from the front-back sensor element 31 input to 3 is subjected to a predetermined calculation, that is, a calculation according to Formula 4, to obtain a calculated value VX2. The calculated value VY2 is a section integrated value of the lateral acceleration, and the calculated value VX2 is a total integrated value of the longitudinal acceleration.

[0034]

[Equation 3]

[0035]

[Equation 4]

In Equation 3, the interval integration is performed for 20 ms which is a specified interval, but this 20 ms is just an example. Further, in Equation 4, the total integrated value obtained by integrating from 0 ms to a certain time t is obtained. As shown in Formulas 3 and 4, the feature of the present invention is that the horizontal axis is the total integrated value of the front and rear sensor outputs and the vertical axis is the section integrated value of the left and right sensor outputs.

Here, the calculated values VY2, V in the present invention
A method of discriminating the non-deployment requirement of the airbag in the symmetrical collision and the deployment requirement of the airbag in the asymmetrical collision using X2 will be described.

The horizontal axis represents the total integrated value (VX2) of the longitudinal acceleration of the vehicle, and the vertical axis represents the section integrated value (VY2) of the lateral acceleration of the vehicle. When converted, it becomes as shown in FIGS. 4 (a) and 4 (b). Fig. 4 (a) shows the case of a symmetric collision, the broken line shows the non-deployment requirement of the airbag at the symmetry collision, and the solid line shows the deployment requirement of the airbag at the symmetry collision. . In addition, Fig. 4 (b) shows the case of an asymmetrical collision, the broken line shows the non-deployment requirement of the airbag at the time of the asymmetrical collision, and the solid line shows the deployment requirement of the airbag at the time of the asymmetrical collision. ing.

As can be seen from FIGS. 4 (a) and 4 (b), the peak position (horizontal axis direction) in both symmetrical and asymmetrical collisions is almost irrespective of airbag deployment and non-deployment requirements. It has the same value. That is, symmetry collision,
There is almost no difference in the vertical axis direction due to the asymmetrical collision, and it is not at a level that can be divided. From this, it can be seen that there is a difference in the energy in the front-back direction when the peak of the left-right acceleration occurs depending on the collision mode. It is considered that this is because the amount of energy in the front-rear direction of the floor until a vehicle body component member such as a side member is broken at the time of a collision of a vehicle differs depending on the collision mode.

Therefore, by utilizing the characteristics of the above-mentioned symmetrical collision and asymmetrical collision, the non-deployment requirement of the airbag in the symmetrical collision and the deployment requirement of the airbag in the asymmetrical collision are shown in FIG. 3 (b). It can be determined using such a determination map. The map of FIG. 3B is stored in the ROM 5, and the value determined by the above-mentioned calculated values VY2 and VX2 is compared with this determination map. In this determination map, the horizontal axis represents the calculated value VX2 and the vertical axis represents the calculated value VY2, and an area AS for determining the asymmetrical collision mode is provided in this map.

In the map shown in FIG. 3 (b), the non-deployment requirement of the airbag in a symmetric collision (shown as a symmetric collision SC in the figure) is indicated by a chain line. Further, the deployment requirement of the airbag for an asymmetrical collision (shown as an asymmetrical collision mode AC in the figure) is indicated by a solid line. here,
The region AS which is determined as the asymmetrical collision mode is the asymmetrical collision mode AC indicated by the solid line, since the calculated value is never in this region in the symmetrical collision mode SC shown by the one-dot chain line in FIG. 3 (b).
Then, the calculated value is in this area.

Therefore, the CPU 4 calculates the calculated values VY2 and VX.
It is detected whether or not the value determined by 2 falls within the area AS for determining the asymmetrical collision type, and the calculated values VY2 and VX2 are detected.
When the value determined by the value falls within the area AS which is determined to be the asymmetrical collision type, a signal indicating the asymmetrical collision type is output to the I / O 3.

As described above, the airbag operating device 1
When signals from the front-rear sensor 1 and the left-right sensor 2 are input to the CPU 4 of 0, the CPU 4 determines whether to activate the airbag device 12 based on the determination table shown in FIG. 5 (a). To do. This determination table has the following three cases. Note that FIG. 5B shows the CPU 4 in this case.
2 is a diagram showing the control logic of FIG.

(1) The case where the output signal from the front / rear sensor 1 of the first case is a high shock signal. In this case, it is determined that the airbag should be deployed only under this condition. So in this case,
It does not matter whether or not the output from the left and right sensors 2 has entered the region where it is determined that the collision type is asymmetrical.

(2) The case where the output signal from the front / rear sensor 1 of the second case is a middle shock signal, and it does not indicate that the output of the left / right sensor 2 has entered the region for discriminating the asymmetrical collision mode. This is the case. In this case, it is determined that the airbag is not deployed.

(3) Third Case: When the output signal from the front-rear sensor 1 is a middle shock signal and when the output of the left-right sensor 2 has entered the region for discriminating the asymmetrical collision mode. Is.
In this case, it is determined that the airbag should be deployed.

When the CPU 4 determines that the airbag should be deployed, the CPU 4 outputs an ignition signal to the drive circuit 11 through the I / O 3. As a result, the drive circuit 11 energizes the squib 13, so that the airbag (not shown) of the airbag device 12 is deployed.

As described above, in the embodiment described above, the airbag actuating device 10 determines the severity of the collision based on the measurement values of the front and rear sensors 1, and the automobile 20 based on the measurement values of the left and right sensors 2. It is determined whether the collision type of the collision is a symmetric collision or an asymmetric collision. When the signal output from the front / rear sensor 1 is determined to be a high shock signal by the determination of the signal from the front / rear sensor 1, the airbag of the airbag device 12 is irrelevant regardless of the determination based on the signal from the left / right sensor 2. Deploy. On the other hand, if the signal output from the front / rear sensor 1 is a middle shock signal based on the determination of the signal from the front / rear sensor 1, the determination based on the signal from the left / right sensor 2 indicates that the airbag is in a symmetric collision mode. The airbag of the airbag apparatus 12 is inflated when the airbag of the airbag apparatus 12 is not deployed and the asymmetrical collision mode is shown. As a result, the number of sensors for detecting the impact can be reduced without lowering the accuracy of the impact detection on the vehicle, and the cost can be reduced while maintaining the performance of the airbag operating device 10.

In the embodiment described above, the airbag actuating device 10 discriminates only the asymmetrical collision type. However, in addition to the discrimination of the asymmetrical collision type, the airbag actuating device 10 has a bad road traveling mode. It is also possible to discriminate. In this case, the ROM 5 shown in FIG. 1 may store a determination map for determining the rough road traveling mode and the collision mode.

Here, the difference between the accelerations generated in the rough road traveling mode and the asymmetrical collision mode will be described with reference to FIGS. 6 (a) and 6 (b). In the rough road traveling mode shown in FIG. 6 (a), low-frequency acceleration occurs over the positive and negative regions. On the other hand, in the asymmetrical collision mode shown in FIG. 6B, high-frequency acceleration is biased toward the positive side or the negative side. Therefore, by utilizing this feature, it is possible to discriminate between the bad road traveling mode and the asymmetrical collision mode. As one method of this determination, in the present invention, by integrating the acceleration of the rough road running form in a wide section integration width, for example, 20 ms width,
The bad road running form is distinguished from the asymmetrical collision form by canceling the energy of the bad road running form generated over the positive and negative regions and reducing the integral value. In addition, since the amount of energy generated is small in the rough road traveling mode, the total integrated value of acceleration in the front-rear direction is also small. Therefore, the map for determining running on a rough road also has a threshold value set in the horizontal axis direction.

FIG. 7 shows an example of the determination map for this rough road running mode. In this determination map, the horizontal axis represents the calculated value VX2 and the vertical axis represents the calculated value VY2. In this map, the region C where the collision type is determined is determined.
A is provided. Here, in the area CA which is determined as the collision type, the calculated value never enters this area in the rough road traveling mode LR shown by the broken line in FIG. 7, and the asymmetric system collision mode AC
Then, the calculated value is in this area.

Therefore, the CPU of the airbag operating device 10
4 detects whether or not the value determined by the calculated values VY2, VX2 falls within the area CA for determining the collision type, and the value determined by the calculated values VY2, VX2 does not fall within the area CA for determining the collision type. Then, a signal indicating the rough road traveling mode is output to I / O3.

As described above, the airbag operating device 1
When signals from the front-rear sensor 1 and the left-right sensor 2 are input to the 0 CPU 4, the CPU 4 determines whether to activate the airbag device 12 based on the determination table shown in FIG. This determination table has the following five cases. Note that FIG. 9 illustrates the control logic of the CPU 4 in this case.

(1) The case where the output signal from the first case front-back sensor 1 is a high shock signal. In this case, it is determined that the airbag should be deployed only under this condition. So in this case,
It does not matter whether or not the output from the left and right sensors 2 has entered the region where it is determined that the collision type is asymmetrical.

(2) The case where the output signal from the front / rear sensor 1 of the second case is a middle shock signal, and it does not indicate that the output of the left / right sensor 2 has entered the region for discriminating the asymmetrical collision type. With
This is a case where the determination based on the outputs of the left and right sensors 2 indicates a bad road traveling mode. In this case, it is determined that the airbag is not deployed.

(3) It is shown that the output signal from the third case front-back sensor 1 is a middle shock signal, and that the output of the left-right sensor 2 has entered the region for discriminating the asymmetrical collision mode. The case where the determination based on the outputs of the left and right sensors 2 does not indicate the bad road traveling form. In this case, it is determined that the airbag should be deployed.

(4) The fourth case shows that the output signal from the front-rear sensor 1 is a middle shock signal, and that the output of the left-right sensor 2 has entered the region for discriminating the asymmetrical collision mode. The case where the determination based on the outputs of the left and right sensors 2 indicates a bad road traveling mode. In this case, it is determined that the airbag is not deployed. In the rough road traveling mode, acceleration in the left-right direction is generated. Therefore, when the asymmetrical collision determination erroneously determines that the collision is an asymmetrical collision, the airbag is deployed in the third case. The morphological determination prevents the airbag from being erroneously deployed.

(5) Fifth case In the case where the output signal from the front-rear sensor 1 is a middle shock signal, and the output of the left-right sensor 2 does not indicate that it has entered the region for discriminating the asymmetrical collision mode. With
This is a case where the determination based on the outputs of the left and right sensors 2 does not indicate a bad road traveling form. In this case, it is determined that the airbag is not deployed.

When the CPU 4 determines that the airbag should be deployed, the CPU 4 outputs an ignition signal to the drive circuit 11 through the I / O 3. As a result, the drive circuit 11 energizes the squib 13, so that the airbag (not shown) of the airbag device 12 is deployed as in the above-described embodiment.

In this embodiment, a rough road is used for determining the severity of a collision based on the measurement values of the front and rear sensors 1 of the above-described embodiment and for determining the collision mode of the automobile 20 based on the measurement values of the left and right sensors 2. By adding the determination of the traveling mode, in addition to the advantages of the above-described embodiment, the collision detection accuracy is further improved.

In the embodiment described above, the output of the left and right sensors 2 is used as it is to judge the asymmetrical collision mode, but compared with the output waveform of the front and rear sensor 1 shown in FIG. The output level of the output waveform (thin line) of the left and right sensors 2 shown in FIG. 9B is low. Therefore, the output value of the left and right sensor 2 having a small output can be weighted as shown by the bold line in FIG. 9B by a calculation such as multiplication by a constant α to increase the output level. Then, the output values of the left and right sensors 2 and the front and rear sensors 1 whose output level is increased
It is possible to determine the collision type of the symmetric system and the asymmetric system by a calculation such as adding the output value of

In the above embodiments, an example of an automobile is described as a vehicle, but the vehicle is not limited to an automobile and the present invention can be applied to a vehicle equipped with an airbag. .

[0063]

As described above, according to the airbag operating device of the present invention, the following effects are obtained.

(1) Since two collision detection sensors arranged close to each other can reliably discriminate between a symmetrical collision and an asymmetric collision, the number of sensors can be reduced and a wiring harness is unnecessary. Moreover, the calculation is simple, and it is possible to reduce the cost without degrading the performance.

(2) It is also possible to discriminate between a bad road traveling form and an asymmetrical collision form.

(3) By weighting the impact force in the left-right direction and combining it with the impact force in the front-rear direction, it is possible to realize an airbag actuating device which can be applied to various vehicles.

[Brief description of drawings]

FIG. 1A is a block diagram showing the overall configuration of an airbag operating device of the present invention, and FIG. 1B is a plan view of an automobile showing an embodiment of the installation position of the airbag operating device of the present invention in an automobile. is there.

FIG. 2A is a block circuit diagram showing a detailed configuration of front and rear sensors used in the airbag operating apparatus of the present invention, and FIG. 2B is a detailed configuration of left and right sensors used in the airbag operating apparatus of the present invention. It is a block circuit diagram showing.

FIG. 3 (a) is an ignition map of one embodiment used to determine the severity of a collision from the values calculated by front and rear sensors in the airbag operating apparatus of the present invention, and (b) is the airbag operation of the present invention. 6 is a determination map of an embodiment used for determining an asymmetrical collision type from calculated values of a front-rear sensor and a left-right sensor in the apparatus.

[FIG. 4] (a) is a graph at the time of a symmetric collision, where the horizontal axis represents the total integrated value of the longitudinal acceleration of the vehicle and the vertical axis represents the integrated value of the lateral acceleration of the vehicle. Is a graph of an asymmetric system collision in which the horizontal axis represents the total integrated value of the longitudinal acceleration of the vehicle and the vertical axis represents the integrated value of the lateral acceleration of the vehicle.

FIG. 5 (a) is a table showing various cases of front and rear sensor output and left and right sensor output in the airbag actuating device of the present invention and a table showing whether or not the airbag is deployed for this case. FIG. 7B is a circuit diagram of a control logic for performing control based on the table of FIG.

FIG. 6A is a diagram showing the generated acceleration in a bad road traveling mode with time, and FIG. 6B is a diagram showing the generated acceleration in an asymmetrical collision form with time.

FIG. 7 is a determination map of an embodiment used for determining a bad road traveling mode and a collision mode in the airbag operating apparatus of the present invention.

FIG. 8 is another embodiment of a table showing various cases of front and rear sensor output and left and right sensor output in the airbag actuating device of the present invention and a table indicating whether or not to deploy the airbag for this case. FIG.

9 is a circuit diagram of a control logic that performs control based on the table of FIG.

FIG. 10 (a) is an output waveform diagram of a front-rear sensor according to still another embodiment of the present invention, and FIG. 10 (b) is an output waveform of the left-right direction sensor and a waveform obtained by weighting the output waveform of the left-right direction sensor. It is a waveform diagram shown.

[Explanation of symbols]

1 ... Front and rear sensor 2 ... Left and right sensor 3 ... Input / output interface circuit (I / O) 4 ... Startup control circuit (CPU) 5 ... Read-only memory (ROM) 6 ... Read / write memory (RAM) 7 ... bus 10 ... Airbag actuating device 11 ... Drive circuit 12 ... Airbag device 13 ... Ignition device (squib) 31 ... Front and rear sensor elements 42 ... Left and right sensor elements

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Rebun Takasuka             1-228 Goshodori, Hyogo-ku, Kobe-shi, Hyogo               Within Fujitsu Ten Limited (72) Inventor, Kibun Iyuda             1 Toyota Town, Toyota City, Aichi Prefecture Toyota Auto             Car Co., Ltd. (72) Inventor Tomoki Nagao             1 Toyota Town, Toyota City, Aichi Prefecture Toyota Auto             Car Co., Ltd. F-term (reference) 3D054 EE06 EE09 EE14 EE19 EE25

Claims (5)

[Claims] 1. A vehicle is provided with a first sensor for detecting the magnitude of impact applied to the front-rear direction of the vehicle and a second sensor for detecting the magnitude of impact applied on the left-right direction of the vehicle. And a control circuit for controlling the deployment of the airbag, wherein the control circuit controls the deployment of the airbag based on impact detection outputs of these two sensors. Is a first threshold value for deploying the airbag in an asymmetrical collision and a second threshold value for deploying the airbag in a symmetrical collision, depending on the magnitude of the impact detection output of the first sensor. And an asymmetrical collision determination region map for determining an asymmetrical collision based on the magnitudes of impact detection outputs of the first sensor and the second sensor. versus When an asymmetric system collision is determined from the system collision determination area map, the airbag is inflated when the impact detection output of the first sensor is equal to or more than the first threshold value. . 2. The airbag operating device according to claim 1, wherein the control circuit is based on a calculated value of a shock detection output of the first sensor and a calculated value of a shock detection output of the second sensor. An airbag actuating device, which operates. 3. The airbag operating device according to claim 2, wherein the calculated value of the impact detection output of the first sensor is a total integrated value of the impact detection outputs of the first sensor, An airbag operating device, wherein the calculated value of the shock detection output of the sensor is an integrated value of the shock detection output of the second sensor within a predetermined time period. 4. The airbag operating apparatus according to claim 1, wherein the control circuit further determines a bad road traveling form based on at least the impact detection output of the second sensor. An airbag actuation device, which is provided with a region determination map for determining a collision type and a rough road traveling type from the region determination map. 5. The airbag operating apparatus according to claim 1, further comprising weighting means for weighting the second sensor output value, wherein the first sensor output and the weighting means output the weighting means. An air bag operating device, wherein the control circuit determines a collision mode of a vehicle symmetric collision and an asymmetrical vehicle collision and controls deployment of the airbag.