JP2006264420A - Deployment control device for air bag - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a deployment control device for an air bag capable of determining difference of a collision form by separating magnitude of acceleration generated at an initial stage of the collision, and performing suitable deployment control of the air bag. <P>SOLUTION: The deployment control device for the air bag comprises an acceleration sensor 2 generating a acceleration signal of a vehicle during the collision, a speed determining circuit 9 determining whether the vehicle is in a high-speed state or in a non-high-speed state from the acceleration signal, a correction stopping circuit 14 stopping correction when the output values of a vehicular front part speed sensors disposed from a bumper armature 101 in a vehicular cabin 106 direction at intervals, an integral processing circuit 11 calculating an integral value by integrating a correction value of the acceleration signal or the acceleration signal, and a deployment determining circuit 12 determining whether the deployment of the airbag is permitted or not by the integral value and a vehicular front part acceleration signal. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an airbag deployment control device that deploys an airbag by detecting a collision of a vehicle.

  As a conventional airbag deployment control device, one as shown in FIG. 8 is known (see, for example, Patent Document 1).

  First, from the configuration, the acceleration sensor (G sensor) 2, the electronic control unit 3, and the inflators 4 and 5 are provided, and the airbag (not shown) is deployed by the two inflators 4 and 5. ing.

  Next, the operation will be described. When the vehicle collides, the acceleration at that time is detected by the acceleration sensor 2, and the detection signal is subjected to arithmetic processing such as integration by the electronic control unit 3 to calculate the collision speed. When the vehicle speed is smaller than the first threshold value, neither of the inflators 4 and 5 is operated. When the collision speed is equal to or higher than the first threshold value and lower than the second threshold value, only one inflator 4 is operated to operate the airbag. When the collision speed is equal to or higher than the first threshold value and the second threshold value, the inflator 5 is activated and the airbag is fully deployed after the inflator 4 is activated.

  As a conventional airbag deployment control device, a device as shown in FIG. 9 is also known (see, for example, Patent Document 2).

  The airbag deployment control device includes an initial collision detection unit 1a disposed at the front end of the vehicle, a collision determination unit 1b disposed at the center of the vehicle (near the shift lever), AND gates 6 and 7, and inflators 4 and 5. The initial collision detection unit 1a and the collision determination unit 1b are each configured by incorporating an acceleration sensor.

  The operation of the airbag deploying device having such a configuration will be described. The initial collision detection unit 1a detects an acceleration signal generated in the initial stage of the collision, and detects the first collision determination signal a1 and the initial stage of the collision. An acceleration signal generated at a later stage is detected and the second collision determination signal a2 is output, and the collision determination unit 1b detects an acceleration signal at the initial stage of the collision to detect a third collision determination signal b1, Then, an acceleration signal generated in the subsequent stage is detected and a fourth collision determination signal b2 is output, and one inflator 4 is operated with a signal based on the logical product of the first collision determination signal a1 and the third collision determination signal b1. Then, the airbag (not shown) is semi-deployed, and the inflator 5 is operated by a signal based on the logical product of the second collision determination signal a2 and the fourth collision determination signal b2, and the air Tsu grayed (not shown) and is adapted to full deployment.

The first to fourth collision determination signals a1, a2, b1, and b2 are all generated based on signals obtained by integrating acceleration signals.
JP-A-10-29494 (FIGS. 1 to 3, paragraphs 0030 to 0039) JP 2001-10441 A (FIGS. 1 to 5, paragraphs 0008 to 0030)

  In the airbag deployment control, the deployment judgment is performed by an algorithm so that the airbag is deployed at the optimal timing by detecting a collision event of the vehicle, and the airbags described in Patent Document 1 and Patent Document 2 are used. In the deployment control device, the collision detection algorithm integrates the signal detected by the acceleration sensor as it is and uses this for the airbag deployment determination.

  However, in the development decision by the algorithm, the integral value does not vary greatly depending on the structure of the vehicle body and the form of the collision, and the value immediately after the collision does not occur. It is difficult to properly separate “de-power development” and “full development under 64 kph ODB (Offset Deformable Barrier) condition, 48 kph oblique condition (high-speed condition)”.

  In addition, taking into account the time until the airbag inflates, it is necessary to determine the deployment determination 30 milliseconds (0.03 seconds) before the occurrence of acceleration causing harm to the occupant. If the severity of the collision is determined at the time of occurrence, there will be a delay in the airbag deployment determination.

  FIG. 10 shows a curve representing an integral value of an acceleration signal detected by an acceleration sensor arranged at the center of the vehicle. Curve A is a 26 kph frontal collision, curve B is a 64 kph ODB collision, and curve C is 48 kph. Each case of oblique collision is shown.

  As is clear from FIG. 10, there is almost no difference in the integral value in the vicinity of 30 milliseconds from the occurrence of the collision (in the portion D in the figure), and it is difficult to distinguish the collision form.

  Accordingly, an object of the present invention is to provide an airbag deployment control device that can determine the difference in the collision mode and perform appropriate deployment control of the airbag by separating the acceleration that occurs in the early stage of the collision. .

  In order to achieve the above object, the present invention provides a vehicle airbag deployment control device having a highly rigid structural member that is disposed in a front portion of a vehicle and extends in the vehicle width direction. Acceleration signal generation means for generating an acceleration signal of the vehicle, speed determination means for determining whether the vehicle is in a high speed state or a non-high speed state from the acceleration signal, and the acceleration signal from the determination result of the speed determination means A vehicle front acceleration signal generated from a correction determination means for determining whether or not to correct the vehicle, and a vehicle front acceleration signal generating means disposed at a distance from the structural member in the direction of the passenger compartment. A correction stop means for stopping the correction when it becomes the above, and a correction value of the acceleration signal when it is determined that the correction determination means performs correction and the correction stop means is not operating When it is determined that no integration and correction is to be performed or when the correction stop unit is activated, an integration processing unit that integrates the acceleration signal to calculate an integral value, and the integrated value and the vehicle front acceleration signal It is an airbag deployment control device having deployment determination means for determining whether or not to permit deployment of a bag.

  Here, the correction value may be a value obtained by multiplying the acceleration signal by a correction coefficient.

  Further, when deployment is permitted by the deployment determination means, a deployment form of the airbag can be determined by adding a result of integrating the acceleration signal to the integrated value.

  Further, the speed determination means compares the acceleration signal measured after the acceleration signal exceeds a threshold value with the threshold value or the previous measurement value, and calculates an absolute value of the difference, and An addition unit that adds each time an absolute value is calculated, and determines whether the vehicle is in a high speed state or a non-high speed state from a calculation result by the addition unit. can do.

  In the present invention configured as described above, it is determined whether the collision occurs in a high speed state or a non-high speed state based on the acceleration signal generated during the vehicle collision, and the determination result of the speed determination unit Depending on the case, it is determined whether or not to allow the airbag to be deployed by integrating the correction value obtained by correcting the acceleration signal.

  Therefore, a clear difference can be made in the integrated value (speed change amount) depending on the speed of the vehicle. For example, acceleration signals such as “26 kph front condition” and “64 kph ODB condition, 48 kph oblique condition” are integrated as they are. This makes it possible to determine the difference in the form of collision that was difficult to isolate.

  Furthermore, since the structural member with high rigidity spreads over almost the entire width of the vehicle, the difference in the collision area due to the difference in the collision mode can be eliminated, and the acceleration generated at the time of collision with the structural member with high rigidity is Regardless of the form, it can be seen as a difference in collision speed.

  In addition, when adopting a method of multiplying the correction coefficient as a means for calculating the correction value, tuning is easy, and it is possible to freely adjust the classification to distinguish the high speed state from the others and the separation to distinguish the low speed state from the others. Can be done.

  Furthermore, by using the integrated value of the acceleration signal to determine the airbag deployment form, it is possible to determine a more stable deployment form as compared with the case where the determination is based on the acceleration that is an instantaneous value.

  Further, the acceleration signal generated during the collision of the vehicle is compared with a previous measurement value to calculate an absolute value, and the vehicle is in a high speed state or a non-high speed state by adding the absolute value. Can be determined.

  With such a configuration, not only the “rising slope” that increases the acceleration signal significantly (when the acceleration in the deceleration direction is positive (+)), but also the “falling Since the “tilt” can also be used as a determination factor, the state of the vehicle can be reliably separated.

  The best mode for carrying out the present invention will be described below with reference to the drawings. The same or equivalent parts as those in the conventional example will be described with the same reference numerals.

  First, from the configuration, as shown in FIG. 1, a bumper armature 101 as a highly rigid structural member is provided at the front portion of the vehicle 100, and a bumper 102 is provided in front of the bumper armature 101. In the rear, a radiator 103 and an engine 104 are provided.

  A pair of side members 105, 105 are extended in the length direction of the vehicle 100 on both sides of the engine 104, and the front end portions of the side members 105, 105 extend close to the bumper armature 101, The end is connected to a front pillar (not shown) that forms the vehicle compartment 106.

  The front end portions of the side members 105 and 105 may be directly connected to the bumper armature 101.

  A collision determination unit 1 in which an acceleration sensor 2 as an acceleration signal generating means is incorporated is disposed at a substantially central portion (near the shift lever) in the front-rear direction and the vehicle width direction of the passenger compartment 106.

  Moreover, as shown in FIG.1 and FIG.2 (SS sectional drawing of FIG. 1), the pillar-shaped food lock stay 107 is attached to the radiator core support (not shown) ahead of the radiator 103. A hood lock stay 107 is provided with a vehicle front acceleration sensor 20 as a vehicle front acceleration signal generating means.

  The distance L between the hood lock stay 107 and the bumper armature 101 is treated as an initial collision stage until the bumper armature 101 is crushed by the collision and the side member 105 starts to deform.

  As shown in FIG. 3, the collision determination unit 1 according to the present embodiment includes an acceleration sensor 2 that generates an acceleration signal at the time of a vehicle collision, a filter circuit 8 for filtering the output of the acceleration sensor 2, and a filter circuit 8 A speed determination circuit 9 that determines whether the vehicle 100 is in a high speed state or a non-high speed state from the acceleration signal output from the vehicle, and a correction determination circuit 10 that determines whether or not to correct the acceleration signal from the determination result. And the correction stop circuit 14 for stopping the correction according to the magnitude of the vehicle front acceleration signal generated from the vehicle front acceleration sensor 20, and the integration value is calculated by integrating the correction value of the acceleration signal or the acceleration signal. An integration processing circuit 11, a deployment determination circuit 12 that determines whether or not to permit deployment of an airbag, and a deployment configuration determination circuit that determines a deployment configuration of the airbag 3 and has a to operate the inflator 4 and 5 by the output of the deployed configuration determination circuit 13.

  The speed determination circuit 9 compares the acceleration signal output from the filter circuit 8 with the threshold or the previous measurement value of the acceleration signal and calculates an absolute value, and sequentially adds the absolute value. It is determined whether the vehicle 100 is in a high speed state or a non-high speed state from the calculation result of the addition unit.

  That is, the acceleration signal output from the acceleration sensor 2 when the vehicle 100 collides may not only constantly increase after the collision, but may decrease. This is because when the vehicle 100 is not crushed by a collision and the reaction force acceleration is generated as an acceleration signal (acceleration is increased), and when the vehicle 100 is crushed and acceleration in the direction opposite to the reaction force acceleration is generated (acceleration is decreased). ).

  If the acceleration signal changes rapidly in this way, it can be determined that the collision is a high-speed collision, so only the “rising slope” that increases the acceleration signal significantly (when the acceleration in the deceleration direction is positive (+)). In addition, the “falling slope” at which the acceleration signal significantly decreases can also be used to clearly distinguish the speed state of the vehicle 100 by using it as a determination factor for the speed of the vehicle 100 at the time of the collision.

FIG. 4 is a diagram showing the relationship between the elapsed time and the accumulated acceleration value for two types of collisions, “64 kph ODB (GS1)” and “26 kph front condition (GS2)”. Here, the chain line T _S represents the speed threshold, this speed for threshold T _S in the predetermined elapsed (Fig. 4 at t = 7.0 ms) to certain values (20G) at a later predetermined time elapsed ( In FIG. 4, until t = 10.0 ms), the threshold value increases in proportion to the increase in elapsed time, and is a threshold value that can determine the slope of the acceleration accumulated value.

  This figure clearly shows that “64 kph ODB (GS1)” in the high speed state and “26 kph front condition (GS2)” in the non-high speed state are clearly separated.

  Next, the processing flow of the airbag deployment control device of the present embodiment will be described with reference to the flowcharts of FIGS.

  First, it is determined in step S1 whether or not the acceleration signal G output from the acceleration sensor 2 at the initial stage of the collision of the vehicle 100 is greater than or equal to the threshold value Th. Perform the process.

  The difference between the acceleration signal G (t) at the elapsed time t after the collision and the acceleration signal G (t-1) measured at the previous measurement time t-1 in the absolute value calculation unit of the speed determination circuit 9 ( G (t) -G (t-1)) is obtained, and its absolute value is set as DG (t) (step S2). When the elapsed time t-1 is when a collision is detected (when the acceleration signal exceeds the threshold value Th), it can be processed as G (t-1) = threshold value Th.

Further, the absolute value DG (t) is added to the previous cumulative value GS (t-1), and the cumulative value GS (t) (= DG (t) + GS (t) as the calculation result of the adding unit. -1)) of the vehicle 100 is compared whether the speed for threshold T _S in determining a non-high-speed state or a high speed state (see step S3, Figure 4).

In this case, if the accumulated value GS (t) is less than the rate for threshold T _S in the vehicle 100 proceeds to step S6 it is determined that the non-high speed state, the cumulative value GS (t) is threshold T _S in more-speed If there is, the vehicle 100 is determined to be in a high speed state, and the process proceeds to step S4.

  In step S4, it is determined whether or not the initial stage of the collision has ended based on whether or not the vehicle front acceleration signal generated from the vehicle front acceleration sensor 20 is equal to or greater than the correction stop threshold. That is, if the vehicle front acceleration signal is equal to or greater than the correction stop threshold, it is determined that the collision has progressed to the extent that the bumper armature 101 in FIG. Since the acceleration signal G (t) can be integrated without correction, the process proceeds to step S6.

  On the other hand, if the vehicle front acceleration signal is less than the correction stop threshold, it is determined that the vehicle is in the initial stage of the collision, and the process proceeds to step S5 where the acceleration signal G (t) is corrected and integrated. In step S5, the acceleration signal G (t) is multiplied by a correction coefficient a (a is a positive integer, for example) to perform integration. Note that the integration performed by multiplying the correction coefficient a can be set so as to switch to the integration without correction after a predetermined time has elapsed.

  In this way, the integral value dV (t) calculated in step S5 or step S6 is compared with the integral threshold value in step S7. If the integral value dV (t) is equal to or greater than the integral threshold value, the vehicle front acceleration signal is again obtained. It is determined whether or not the collision stop stage is completed by determining whether or not the correction stop threshold is exceeded.

  If the initial stage of the collision has ended, the process proceeds to airbag deployment pattern determination (step S9). If not, the process returns to step S2 to repeat the above-described processing. That is, if the vehicle front acceleration signal is less than the correction stop threshold, it can be determined that the collision is not a significant collision even if the integral value dV (t) is equal to or greater than the integral threshold. .

  When a predetermined reset condition is satisfied when returning to step S2 and repeating the process, the calculation is performed after resetting the accumulated value GS (t) and integral value dV (t) of the absolute value to 0. Resume processing.

  In the airbag deployment type determination process of FIG. 6, is depower deployment (step S13) that operates one inflator 4 or full deployment (step S12) that activates two inflators 4 and 5? Judging.

  First, an integration value dV (t + 1) is calculated by integrating the acceleration signal G (t + 1) generated after the transition to the development form determination process without correction (step S10), and this integration value dV (t +1) is compared with the deployment form threshold value to determine the airbag deployment form (step S11).

  FIG. 7 is a diagram showing the relationship between the elapsed time and the acceleration integral value for two types of collisions of “26 kph front condition” and “64 kph ODB”, and FIG. 7A integrates the acceleration signal as it is without correction. FIG. 7B shows the result of processing performed by the airbag deployment control device of the present embodiment.

Here, solid lines X1 and Y1 indicate a collision of “64 kph ODB”, broken lines X2 and Y2 indicate a collision of “26 kph front condition”, and alternate long and short dash lines T _X and T _Y indicate a deployment form threshold.

As shown in FIG. 7A, both “64 kph ODB (X1)” and “26 kph front condition (X2)” do not exceed the development form threshold value T _X , and the two curves are close to each other. It can be seen that it is difficult to separate the two collisions.

On the other hand, "64kphODB (Y1)" and "26kph front conditions (Y2)" in FIG. 7 (b), are cut clearly across the deployed configuration threshold T _Y.

  As described above, according to the present embodiment, when it is determined that the vehicle 100 is in the high speed state at the initial stage of the collision, the acceleration signal is multiplied by a multiple (correction coefficient a) and integration is performed using a corrected value.

  For this reason, the integrated value in the high speed state of the vehicle 100 can be made larger than the actual value compared with the integrated value in the non-high speed state. For example, “26 kph front condition”, “64 kph ODB condition, 48 kph oblique condition”, etc. It becomes possible to determine the difference in the form of collision, which was difficult to isolate by simply integrating the acceleration signal.

  Furthermore, since the highly rigid bumper armature 101 is spread over almost the entire width of the vehicle, it is possible to eliminate the difference in the collision area due to the difference in the collision form. Regardless of the form of the collision, it can be regarded as a difference in collision speed.

  Further, by multiplying the acceleration signal when it is determined as the high speed state as the correction value calculation means by the correction coefficient a that is a multiple, it becomes easy to distinguish the high speed state from the non-high speed state. Furthermore, tuning can be easily performed only by changing the correction coefficient a.

  Then, by using the integrated value of the acceleration signal to determine the deployment form of the airbag, it is possible to determine the deployment form that is more stable than the case of judging by the acceleration that is an instantaneous value.

  Further, even if an erroneous determination is made in the determination of the speed state of the vehicle 100, since the airbag deployment permission is performed based on the integrated value, it is possible to prevent the airbag from being erroneously deployed.

  Further, when the airbag deployment permission is finally determined, the vehicle front acceleration signal is compared with the correction stop threshold value so that the airbag is deployed in a low speed state or a state where it should not be deployed. Misdeployment can be prevented.

  Although the best embodiment of the present invention has been described in detail with reference to the drawings, the specific configuration is not limited to this embodiment, and design changes that do not depart from the gist of the present invention are possible. Are included in the present invention.

  For example, in the above-described embodiment, the example in which the bumper armature 101 is installed in the vehicle as a structural member has been described. It should just be extended to.

  In the above embodiment, the acceleration signal when the vehicle 100 is in the high speed state is corrected by multiplying it by an integer, but the present invention is not limited to this, and the acceleration signal when the vehicle 100 is in the non-high speed state is reduced. The difference from the high speed state may be clarified by correcting by multiplying several times and making the integral value in the non-high speed state smaller than the actually measured value.

  In the above-described embodiment, the acceleration accumulated value obtained by accumulating the absolute value of the difference between the acceleration signals is used as the speed determining means for determining whether the vehicle 100 is in the high speed state or the non-high speed state. For example, the acceleration measured at each elapsed time after a collision memorizes the time that crosses two thresholds with different magnitudes to determine the length of the time, and the time length is shortened. For example, it may be a speed determination unit that determines that the acceleration is steep and is in a high speed state.

It is a top view explaining the installation state to the vehicle of the airbag deployment control apparatus in the best embodiment of this invention. It is SS sectional drawing of FIG. It is a block diagram explaining the collision judgment unit of the airbag deployment control apparatus in the best embodiment of the present invention. It is a graph explaining separation of the speed state of the vehicle in the best embodiment of the present invention. 5 is a flowchart of signal processing in the best mode for carrying out the present invention (before determination of development form). It is a flowchart (development form judgment) of the signal processing in the best embodiment of the present invention. (A) It is a graph of the curve showing the acceleration integral value by the conventional airbag deployment control apparatus, (b) It is the graph of the curve showing the acceleration integral value by the airbag deployment control apparatus of this invention. It is a block diagram explaining an example of the conventional airbag deployment control apparatus. It is a block diagram explaining the other example of the conventional airbag deployment control apparatus. It is a graph of the curve showing the integral value of an acceleration signal.

Explanation of symbols

1 collision determination unit 2 acceleration sensor (acceleration signal generation means)
20 Vehicle front acceleration sensor (vehicle front acceleration signal generating means)
9 Speed judgment circuit (speed judgment means)
10 Correction determination circuit (correction determination means)
11 Integration processing circuit (integration processing means)
12 Deployment determination circuit (deployment determination means)
13 Development form determination circuit 14 Correction stop circuit (correction stop means)
Th threshold 100 Vehicle 101 Bumper armature (structural member)
106 Car compartment

Claims (4)

A vehicle airbag deployment control device having a highly rigid structural member disposed in the vehicle front portion and extending in the vehicle width direction,
Acceleration signal generation means for generating an acceleration signal of the vehicle during a collision, speed determination means for determining whether the vehicle is in a high speed state or a non-high speed state from the acceleration signal, and a determination result of the speed determination means The vehicle front acceleration signal generated from the correction determination means for determining whether or not to correct the acceleration signal from the vehicle, and the vehicle front acceleration signal generation means arranged at a distance from the structural member in the direction of the passenger compartment A correction stop means for stopping the correction when the correction stop threshold is equal to or greater than the correction stop threshold, and integrating the correction value of the acceleration signal when the correction determination means determines that the correction is to be performed and the correction stop means is not operating. When it is determined that no correction is to be performed or when the correction stop unit is activated, an integration processing unit that integrates the acceleration signal to calculate an integral value; and Airbag deployment control apparatus characterized by having a deployment determining means for determining whether or not to permit the deployment of the airbag by the vehicle front acceleration signal.   2. The airbag deployment control device according to claim 1, wherein the correction value is a value obtained by multiplying the acceleration signal by a correction coefficient.   3. The airbag deployment mode according to claim 1, wherein when deployment is permitted by the deployment determination unit, an airbag deployment form is determined by adding a result obtained by integrating the acceleration signal to the integral value. Airbag deployment control device.   The speed determination means includes an absolute value calculation unit that compares the acceleration signal measured after the acceleration signal exceeds a threshold value with the threshold value or a previous measurement value, and calculates an absolute value of the difference, and the absolute value 2. An addition unit that adds each time the vehicle is calculated, and determines whether the vehicle is in a high speed state or a non-high speed state from a calculation result of the addition unit. 4. The airbag deployment control device according to any one of 3.

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