JP2776161B2 - Collision detection device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a collision detection device used for detecting a collision for an occupant protection airbag installed in a vehicle, for example.

[0002]

2. Description of the Related Art In order to enhance safety in the event of a vehicle collision, two types of airbag devices, one for a frontal collision and one for a side collision, may be mounted in preparation for a frontal collision and a side collision of the vehicle. And those described in the specification (unknown) attached to the application of Japanese Patent Application No. 3-293551.

As shown in FIG. 11, a front collision airbag device 2 is provided on an instrument panel 1 in front of a passenger seat in a passenger compartment, and a side collision airbag device is provided in a side door 3 on the side of the passenger seat. Bags 4 are provided respectively. Then, for example, at the time of a frontal collision of the vehicle, an inflator (not shown) of the airbag device 2 for frontal collision ignites, the airbag is inflated by the generated gas, and deployed to the front of the occupant. In the side collision airbag 4, gas generated by the inflator of the front collision airbag device 2 at the time of a side collision is supplied through the ducts 5 and 6 by a valve switching operation. And expands to the side of the occupant to protect the occupant from secondary collision with the window glass of the side door 3 or the like.

[0004]

As described above, even when the airbag device for frontal collision and the airbag device for side collision are equipped together, the ignition control of each is generally performed independently. is there. In addition, frontal collisions and side collisions are distinguished by the type of collision of the vehicle, and when the deceleration occurs mainly in the forward direction, the occupant moves forward, and a front collision airbag is required. When acceleration is applied in the left-right direction, a side collision airbag is required for the occupant to move left or right.

[0005] By the way, for example, in side collision,
When another vehicle collides with the side surface of the running vehicle, both lateral acceleration and longitudinal acceleration are detected. Also, in the case of a collision from an oblique front or an oblique side, both the acceleration in the front-rear direction and the acceleration in the left-right direction may be detected.

In the case of such a collision mode, the actual collision magnitude is the level at which the airbag is activated, but the collision level detected by both the frontal collision sensor and the side collision sensor is not sufficient. In some cases, the respective airbags become lower and do not actuate the respective airbags.

[0007] This invention has been made in view of the above, perform vector operations based on the two directions of the acceleration detected by the sensor, can in detecting the collision direction and collision intensity with high accuracy, and, Air corresponding to the direction of vehicle collision
Inflate and deploy the bag properly, and
It is an object of the present invention to provide a collision detection device that can prevent necessary deployment and malfunction .

[0008]

The invention of claim 1 as a means for solving the above problems BRIEF SUMMARY OF THE INVENTION As shown in FIG. 1,
An acceleration sensor A for detecting the two directions of the acceleration of the longitudinal direction and lateral direction of the vehicle, respectively, the two directions of acceleration detected by the acceleration sensor A synthesized by vector operation, vector direction determined by the operation When,
The collision direction of the vehicle based on the absolute value of the magnitude
Collision direction and strength detection to calculate collision and acceleration
Output means B and a reference value for determining whether or not the vehicle is in a collision state,
A judgment level setting means C preset for each collision direction;
Detected by the collision direction and collision strength detection means B
Acceleration reference value corresponding to the collision direction
And collision acceleration detected by collision strength detecting means B
Collision judgment by comparing the degree
Means D and a vehicle collision performed by the collision determination means D
Based on the determination result of the state, the front-back direction of the vehicle or
Front-impact airbags provided separately for left and right directions
Or, in the side collision airbag, the collision direction and the collision
Corresponds to the collision direction detected by the impact strength detection means B
Airbag deployment control to control airbag inflation and deployment
Means E.

[0009]

[0010]

[0011]

With the above construction, the collision detecting device of the present invention is provided with an acceleration sensor for detecting the collision in the longitudinal direction of the vehicle.
And acceleration in two directions, left and right, are detected respectively.
And the collision direction and the collision strength detection means,
Direction acceleration is synthesized by vector operation, and
Vector direction obtained by vector operation
Collision direction and acceleration based on the magnitude of the magnitude
(Collision strength) is calculated. On the other hand, judgment level setting means
The reference value for determining whether the vehicle is in a collision state
It is set in advance for each direction. Then, the collision determining means
Detected by the collision direction and collision strength detection means.
The acceleration reference value corresponding to the collision direction
And the collision acceleration detected by the collision strength detection means
A comparison is made to determine whether a vehicle collision has occurred. Then
Based on the judgment result of the vehicle collision state by the collision judgment means
And the airbag deployment control means
E corresponding to the collision direction detected by the
The inflation and deployment of the bag is controlled.

[0012]

[0013]

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment in which the collision detecting device of the present invention is applied to an airbag device for a vehicle will be described below with reference to the drawings.

FIG. 2 to FIG. 10 show an embodiment of the present invention. As shown in FIG. 5, as shown in FIG. In FIG. 1, side airbag modules 12a and 12b accommodating a folded airbag and an inflator are provided to be supported by a door inner panel (not shown). In addition, an airbag operation control device 13 for controlling the operation of each airbag and an acceleration sensor (hereinafter, referred to as a G sensor) 14 for detecting the collision are provided at a lower portion of the center console located substantially at the center of the vehicle body. .

Further, in front of the driver's seat M, an airbag module 16 for a frontal collision M seat mounted with an inflator is provided at the center of the steering wheel 15, and an instrument panel 17 in front of the passenger seat P. Inside, similarly, a front-seat airbag module 18 for a front collision, in which an airbag and an inflator are integrally housed, is provided.

The G sensor 14 is, for example, a semiconductor G sensor 19 shown in FIG. This is due to deformation of the metal cantilever portion 19a, the gauge portion 19b formed at the base of the cantilever portion 19a, and the gauge portion 19b when the tip side of the cantilever portion 19a swings as a weight. And an integrated circuit section 19c for extracting a resistance change as a signal. This semiconductor G
The sensor 19 can be used as a front collision G sensor if the cantilever portion 19a is attached so as to be swingable in the front-rear direction of the vehicle body.
If the cantilever portion 19a is mounted so as to be swingable in the left-right direction of the vehicle body, it can be used as a side collision G sensor. Can be.

As shown in the block diagram of FIG. 2, the control device 13 for controlling the operation of the airbag includes a longitudinal acceleration sensor 14a for detecting a frontal collision of the vehicle and a lateral acceleration sensor for detecting a side collision. A / D converters 22 and 23 for converting the detection values detected by the A / D converter 14b into digital signals, respectively, and determining the ignition of the airbag based on the digital signals input from the A / D converters 22 and 23. And a microprocessor 24 for performing various operations. A microprocessor is provided between the microprocessor 24 and each of the squibs 26a, 26b, 26c, 26d of the ignition circuit 25 of the airbags 12a, 12b, 16, 18. The ignition signals output from the processor 24 are connected so as to be transmitted to the respective squibs 2.
6a, 26b, 26c, 26d are connected to a power supply via a safing sensor 27, respectively.

The safing sensor 27 is for preventing a malfunction of the airbag at the time of non-collision. For example, the safing sensor 27 shown in FIG.
1 and a roller-mite-type safing sensor 25 shown in FIG.

In the former safing sensor 21, a predetermined amount of mercury 23 is put in a test tubular container 22, and the container 2
It is sealed in a state where the yin and yang electrodes 24, 24 are arranged apart from each other on the upper part of 2, and is attached in a state of being inclined in a direction in which a collision load is applied (to the left or right of the vehicle body). The mercury 23 collected in the bottom of the container 22 by the action of gravity in a normal state, when the above collision load constant is applied to the vehicle body during a side collision, the mercury 23 is inclined inner surface of the container 22 by its inertial force It rises and moves to the position of the electrode 24 to make both the electrodes 24 and 24 conductive. Also, when there is no collision or when the applied load is small, the mercury 23 in the container 22 does not move to the position of the electrode 24, so that the squib does not ignite because the safing sensor 21 does not conduct, and an air bag is not required. Deployment can be prevented,
By leaving the airbag on the non-collision side without being ignited, the airbag can be effectively used at the time of a side collision occurring thereafter.

In the latter safing sensor 25, a roller 27 having one end of a plate spring 26 wound on the outside, a rotary contact 28 formed on the surface of the roller 27, and the plate spring 26 not being wound. Fixed contact 2 protruding from an opening formed on the other end side
9 is provided. At the time of non-operation, the roller 27 is in contact with the stopper 30 due to the desired set load of the plate spring 26, and the fixed contact 29 and the rotating contact 28
Is away. When a collision load is applied to the side of the vehicle body , the roller 27 rotates due to its inertia,
The rotary contact 28 provided in the first position moves and comes into contact with the fixed contact 29 to output an ON signal.

In the microprocessor 24, as shown in FIG. 3, data detected by the longitudinal acceleration sensor 14a and the lateral acceleration sensor 14b are A / D-converted, and further processed by integration or the like. A vector operation is performed based on fx and fy to determine a collision strength and a collision direction.

[0023] That collision strength, (fx ² + fy ²⁾ the square root of the comparison of whether the value is pre Me set threshold values for each collision direction of the vehicle (reference value) is greater than f Th And the collision direction θ is determined by (tan ⁻¹ · fy / fx), and the airbag to be deployed is determined from the value (= angle) of the collision direction θ.

As a result, when the square root of (fx ² + fy ² ) is larger than the threshold, the inflator of the airbag module at the position corresponding to the collision direction θ is ignited, and the generated gas inflates the airbag. Let it unfold.

As the numerical values used in the calculation by the microprocessor 24, as shown in FIG. 6, the detected values Gx and Gy of the two acceleration sensors 14a and 14b are used as they are, or the detected values Gx and Gy are used. Use the one-time integration values Vx, Vy of Gy, or use the detection values Gx, Gy
Can be used. The one-time integral values Vx and Vy correspond to the speed of the collision, and the two-time integral values Sx and Sy correspond to the moving distance of the occupant at the time of the collision.

Next, the operation of this embodiment configured as described above will be described with reference to FIGS. 3 and 4.
When another vehicle collides with the side door 11 on the side of the vehicle, the front-rear direction acceleration sensor 14a and the left-right direction acceleration sensor 14b of the acceleration sensors 14 provided substantially at the center of the vehicle body The acceleration in the front-rear direction and the left-right direction is detected. The detected values Gx and Gy are A
After the / D conversion, they are processed into operation values fx and fy to be used for the judgment operation as shown in FIG. And step
At 1, the crash strength, the square root of (fx ² + fy ² ), is calculated. In step 2, the collision direction θ, that is, (tan ⁻¹ · fy / fx) is calculated. Then, in step 3, the calculated (fx ² + f
The square root of y ² ) is compared with a threshold value fTh. If the root is equal to or smaller than the threshold value, the process returns to step 1 and the airbag is not deployed. In step 3, (fx ² + f
Step 4 if the square root of y ² ) is greater than the threshold
Proceed to.

In step 4, the airbag to be deployed is determined based on the value of the collision direction θ calculated in step 2. For example, as shown in FIG.
If the front collision threshold is greater than the absolute value of
If lθl <θF, it is determined that a frontal collision has occurred, and the front airbag module 16 for the M-seat disposed at the center of the steering wheel 15 and the instrument panel 17 in front of the passenger seat P are provided. Each of the inflators of the front passenger airbag module 18 for front collision is ignited, and the generated airbag inflates and deploys the airbag, thereby forming a secondary airbag with the steering wheel 15 and the instrument panel 17. Protect occupants from collisions.

The value of θ obtained is -θ S <θ <−θ
In the case of F, it is determined that the vehicle has collided with the left side surface of the vehicle body, and the inflator of the side airbag module 12b housed in the left side door is ignited, and the generated gas inflates and deploys the airbag. Protects occupants from secondary collisions with the left side door inner wall and window glass.

Further, the obtained value of θ is θF <θ <θS
In the case of, the collision is determined to be a collision with the right side of the vehicle body, the inflator of the side airbag module 12a housed in the right side door is ignited, and the airbag is inflated and deployed by generated gas, Protects occupants from secondary collision with the right side door inner wall and window glass.

Therefore, when both a sensor for detecting a forward collision and a sensor for detecting a side collision detect a collision at the time of a vehicle collision, the accelerations G in two directions, forward and lateral, are detected.
Is calculated, and the determination of the ignition of the airbag, the determination of the ignition direction, and the determination of the airbag to be ignited are performed based on the obtained vector value. The bag can be inflated and deployed.

At this time, in the case of a side collision, as a member for absorbing a collision load, only a side door or other component material on the side of the vehicle body is used to absorb the impact, and various components installed in the engine room, chassis members, etc. There is a problem that the impact of the collision is more likely to affect the occupant than in the case of a front collision where the vehicle is compressed to absorb the impact. Therefore, the criterion for determining a side collision, that is, the side collision threshold value is set to be smaller than the threshold value for a front collision.

For example, as shown in FIG. 7, in the case of a collision into a fan-shaped front collision area which is opened from the front of the vehicle body to the right and left at an angle θ (θ = about 30 degrees), the collision criterion is determined due to the large amount of shock absorption. In the case of a collision in a side collision area that is opened 90-θ degrees diagonally forward from the side of the vehicle body, the amount of impact absorption by the side doors is small, so that the occupant can be reliably protected. By setting the value used as a collision criterion smaller than that in the case of a frontal collision, even if the collision load is relatively smaller than in the case of a frontal collision, it is determined that a collision has occurred and the safety of the occupant is ensured. ing.

The boundary between the front collision area and the side collision area overlaps in a range of a predetermined angle α (about 5 to 10 degrees). , Both the front collision airbag and the side collision airbag are deployed to protect the occupant.

The above embodiment has been described with reference to a typical example. The collision detection device of the present invention is not limited to this embodiment. The present invention may be applied to a vehicle provided with an airbag device for collision.

[0035]

[0036]

Collision detecting device of the invention, as described above, according to the present invention detects the collision intensity collision direction of vehicles with high precision
be able to. And the front-back and left-right directions of the vehicle
Front airbags provided separately for
Is the side collision airbag, which may cause a secondary collision
Airbags positioned in different directions based on their impact strength.
And can be reliably expanded and deployed. Also secondary
Airbags located in a direction where there is no possibility of collision
Malfunctions such as expansion and deployment are avoided, and
Even if the airbag responds, the impact strength is minimal.
Unnecessary deployment of the airbag is avoided when
You.

[Brief description of the drawings]

1 is a block diagram showing the basic configuration of the present invention.

FIG. 2 is a diagram showing a circuit configuration of a collision detection device according to one embodiment of the present invention.

FIG. 3 is a flowchart showing a control program of an airbag.

FIG. 4 is an explanatory diagram showing a relationship between a calculated value and a collision direction.

FIG. 5 is a layout diagram of an airbag module and a control device.

FIG. 6 is an explanatory diagram showing types of operation values used for comparison determination.

FIG. 7 is an explanatory diagram showing a magnitude of a threshold value set for each vehicle body part.

FIG. 8 is a perspective view of a semiconductor acceleration sensor.

FIG. 9 is a perspective view of a mercury-type safing sensor.

FIG. 10 is a perspective view of a roller-mite-type safing sensor.

FIG. 11 is a perspective view showing an example of a conventional airbag device having both a front collision and a side collision.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 11 Side door 12a Side airbag module 12b Side airbag module 13 Control device 14 Acceleration sensor 14a Front / rear direction acceleration sensor 14b Left / right direction acceleration sensor 15 Steering wheel 16 M seat airbag for front collision 17 Instrument panel 18 Front collision Airbag for P seat 19 semiconductor G sensor 21 safing sensor 24 microprocessor 25 safing sensor

Claims (1)

(57) [Claims] 1. An acceleration sensor for detecting accelerations in two directions of a front-rear direction and a left-right direction of a vehicle, respectively, and accelerations in two directions detected by the acceleration sensors are combined by a vector calculation, and the calculated values are obtained by the calculation. Vect
The vehicle direction based on the absolute direction of the vehicle
Collision direction and collision acceleration
Collision strength detecting means and a base for determining whether or not a vehicle is in a collision state;
The reference value is set in advance for each collision direction.
And the collision direction and the collision strength detecting means.
The reference value of acceleration corresponding to the direction of collision
The collision force detected by the direction and collision strength detection means
The speed is compared with the speed to determine whether the vehicle is in a collision state.
Determining means and a vehicle collision state performed by the collision determining means.
Based on the determination result of the vehicle state,
There is a front airbag separately provided corresponding to the right direction.
Or the collision direction and collision
Air corresponding to the collision direction detected by the strength detection means
Collision detecting device characterized by having an air bag deployment control means to control the expansion and deployment of the bag.