JP3099624B2 - Vehicle occupant protection system - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle for coping with a collision accident caused by an abnormal approach of a host vehicle to an object such as a preceding vehicle ahead of the host vehicle in the traveling direction, and for reducing the impact of an occupant. Occupant protection device.

[0002]

2. Description of the Related Art Conventionally, as this kind of vehicle occupant protection device, there is one disclosed in, for example, Japanese Utility Model Laid-Open No. 55-135563. That is, the obstacle detection radar is used to detect the relative speed and the relative distance between the object ahead of the own vehicle and the own vehicle and the own vehicle, and to detect the relative speed and relative distance of the object based on the detected relative speed and relative distance. When it is determined that the vehicle collides,
The seat belt is locked at the same time when the brake is operated.

Further, as disclosed in Japanese Patent Application Laid-Open No. 2-246838, a relative speed and a relative distance between an object ahead in the traveling direction of the host vehicle and the host vehicle are detected using a preceding situation monitoring unit. From the relationship between the detected relative speed and the relative distance, the degree of abnormal approach between the object ahead of the own vehicle and the own vehicle and the own vehicle is determined, and according to the degree of abnormal approach, first throttle control is performed. In some cases, brake control is performed at the same time as a warning is issued, and then control for occupant protection is performed in multiple stages, such as by controlling the tension of the seat belt.

[0004]

However, in the case of such a conventional vehicle occupant protection system as described above, detection of the relative speed and the relative distance between the object ahead of the own vehicle in the traveling direction and the own vehicle is performed. Since the mechanism for protecting the occupant is operated based on the value, the mechanism for protecting the occupant is operated only at the predicted time. For this reason, for example, even if an object such as a cardboard box is an object in front of the own vehicle in the traveling direction and is hardly affected even if it comes into contact while the vehicle is running, it is determined that the object collides with the own vehicle. At times, there is a problem that an operation such as locking a seat belt is performed.

The present invention has been made in view of the above-mentioned circumstances, and has as its object the purpose of protecting the occupant if the vehicle is hardly affected even if the vehicle comes into contact with the vehicle while traveling. An object of the present invention is to provide a vehicle occupant protection device in which the operation of the device is avoided and the safety device is operated only when it is necessary to protect the occupant.

[0006]

According to the present invention, a distance sensor 1 for detecting a distance from a host vehicle to an object in front of the host vehicle is provided, as shown in FIG. , A pressure-sensitive sensor 2 that detects contact with an object, a safety device 3 that protects an occupant in the vehicle, and a distance to the object detected by the distance sensor 1 .
Based on the amount of change per unit time, the relative speed calculating means 5 for calculating a relative velocity between the vehicle and the object, the distance
The distance to the object detected by the separation sensor 1;
Based on the relative speed calculated by the relative speed calculation means 5
Determining means 6 for determining whether or not the own vehicle collides with the object;
When it is determined that a collision occurs, the distance sensor 1
The distance detected by the relative speed calculating means 5
Own vehicle based on the calculated relative speed
Collision time calculation means 7 for calculating the time required to impinge on the required calculated by the collision time calculation means 7
Setting means 8 for setting a predetermined time area on the basis of time, and within the time area set by the setting means 8 ,
When the contact of an object is detected by the pressure sensor 2
And safety control means 9 for operating the safety device 3.

[0007]

According to the vehicle occupant protection device of the present invention, the distance
The distance to the object detected by the separation sensor 1 and the relative
Based on the relative speed calculated by the speed calculating means 5
Is judged by the judging means 6 that the own vehicle collides with the object.
The distance detected by the distance sensor 1
And the relative speed calculated by the relative speed calculation means 5
The own vehicle is turned into an object by the collision time calculation means 7 based on
Calculate the time required until collision. And this required
A predetermined time area is set by the setting means 8 based on the time.
Within the set time range, the pressure sensor 2
When the contact of an object is detected by the
The safety device 3 will be operated more .

[0008]

FIG. 2 is a block diagram showing the system configuration of a seat belt pretensioner device according to an embodiment to which the vehicle occupant protection device of the present invention is applied.

The seatbelt pretensioner device of this embodiment includes a distance sensor 1, a pressure sensor 2, and a seatbelt pretensioner main body 3A mounted on a seatbelt for reducing the impact force of an occupant in the vehicle. And a CPU 4 corresponding to the control unit 4 in FIG.

In this embodiment, the distance sensor 1 employs an ultrasonic oscillation type distance sensor, but a laser pulse transmission type distance sensor can also be used. Also,
The present invention is not limited to these, and if a relative distance between an object such as a vehicle ahead of the own vehicle in the traveling direction (hereinafter abbreviated as “preceding vehicle”) and the own vehicle can be detected, the passive distance can be detected. A triangulation distance sensor or the like may be used.

In this embodiment, the pressure sensor 2 is linearly attached along the inside of the vehicle bumper (the front side of the vehicle body) as shown in FIG.
The pressure-sensitive rubber switch 2A shown in FIG. The pressure-sensitive rubber switch 2A is formed by covering a laminated structure in which a pressurized conductive rubber 2D is interposed between flat knitted conductors 2B and 2C with silicon rubber 2E. Then, inside the pressurized conductive rubber 2D, as shown in the operation principle diagram of FIG.
Is in a non-conducting state, and when F becomes a predetermined size or more, it becomes a conducting state. When this conduction state occurs in at least a part of the pressure-sensitive sensor 2, a collision signal is output from the pressure-sensitive sensor 2. However, when a light obstacle such as a cardboard on the road collides with the bumper, it must be possible to avoid issuing a collision signal. Since the bumper itself can absorb a certain amount of impact, the switch does not become conductive in a low-speed collision, but may conduct in a high-speed collision. For this reason, in order to prevent such a malfunction at the time of collision, the operating pressure per unit length is adjusted by adjusting the hardness, thickness, and the like of the silicone rubber for coating. For example, the minimum operating pressure of the switch may be set to about 30 kgf / cm so that the switch does not become conductive even if the cardboard containing the contents and weighs 5 kg collides with the bumper for 30 cm. Here, regarding the operating pressure, the vehicle speed at the time of a vehicle collision is 60 km / h and the collision time is 10 msec.
Was calculated as Further, the pressure-sensitive sensor 2 is not limited to the above-described configuration, but may be provided at the tip of the vehicle and can output a collision signal under the above-described conditions when it collides with an object. It can be applied even if it has a simple structure.

The seat belt pretensioner main body 3A
In this embodiment, the webbing 11 is attached to a three-point seat belt in this embodiment, and the webbing 11 as shown in FIG. 5 is always in a slack state, and operates to take up the slack in an emergency. Of course, this can also be applied to seat belts with four points or the like.

The CPU 4 executes the respective processing operations of the relative speed calculating means 5, the judging means 6, the collision time calculating means 7, the setting means 8 and the safety control means 9 described with reference to FIG.
Is performed as described below in accordance with the flowchart of FIG.

In this embodiment, an inter-vehicle distance sensor 1 of an ultrasonic pulse transmission type is used.
Ultrasonic waves having a predetermined pulse width are transmitted at certain predetermined time intervals. When an object such as a vehicle exists in front of the vehicle, the ultrasonic pulse is reflected, and the reflected wave is received by the receiver.

First, as a detection process by the distance sensor, the delay time from sending out the ultrasonic wave to receiving the reflected wave is measured, the time is multiplied by the sound speed, and the result is divided by 2 to obtain the object. (Step F
1). By obtaining this distance data cyclically, the distance data (D (t + δt)) measured this time, the previous value data (D (t)), and the pulse transmission interval value (δt) are used to calculate the relative distance of the object. A process as a relative speed calculating means for calculating the speed difference Vr ((D (t + δt) -D (t)) / δt) is executed (step F2).

Next, the process proceeds to a determination process. If the relative speed difference Vr is positive (leaving state), the inter-vehicle distance between the host vehicle and the object does not become 0, so that the process does not proceed to the next step (step F3). . If this value is negative, step F
4 and the braking distance estimation value Ds (−Vr ² / (2G
m)) is executed as a collision time calculating means for calculating (m)). This Ds is a deceleration (Gm) assumed in advance.
Below, the inter-vehicle distance value that changes until the relative speed difference becomes zero. The normal deceleration can be changed by the operation of the road surface or the driver. For example, a representative value is set to -0.5 G (1 G = 9.8 m / s / s).

Next, at step F5, Ds is compared with the current inter-vehicle distance value D (t). At this time, Ds becomes D (t)
If Ds <Ds (t) that is shorter than that, it is determined that the possibility that the own vehicle collides with the object is low, and the process does not proceed to the next step. On the other hand, if Ds is shorter than D (t), the own vehicle may approach and collide with the object, and the inter-vehicle distance between the own vehicle and the object becomes zero as shown in FIG. Then, a margin time t (estimated value: T = -D (t) / Vr) is calculated (step F6). In the present embodiment, for example, when the margin time T is 0.2 seconds or less (step F7),
When the absolute value of the relative speed difference (collision speed) is equal to or greater than 10 km / h (step F8), it is predicted that the own vehicle, which is presumed to require the pretensioner operation, will collide with the object (step F9). Next, after predicting that the vehicle will collide with an object, the pressure-sensitive sensor 2 installed inside the bumper or the like is used.
Performs a process as a setting means for measuring a time T ′ until it is actually turned on after receiving an impact (step F10),
When the time T 'is within the predetermined time range T ± 0.05 seconds (step F11), it is determined that the approach prediction in step F9 is valid, and safety control for immediately operating the pretensioner is performed. Execute processing as means. (Step F12) As described above, in the present embodiment, when it is determined that there is a high possibility that the host vehicle collides with the object, the time required until the host vehicle collides with the object is calculated, and the required time is used as a reference. As a predetermined time region in which the collision signal from the pressure sensor can be detected is set, and when the collision signal is generated in the pressure sensor within the predetermined time region, the pretensioner is operated, so that the vehicle If the contact is hardly affected by the contact while driving, keep the pressure sensor from generating a collision signal.
Only when a collision has occurred.

Moreover, the pressure-sensitive sensor 2 not only has a short transition time from the output corresponding to the non-contact state to the output corresponding to the contact state, but also is installed in a bumper or the like at the front end of the vehicle. At the same time, the reaction starts promptly, and as shown in FIG. 5, the output of the pressure-sensitive sensor 2 is observed in a time region of T ± 0.05 seconds after the prediction of approach, so that the accuracy of collision detection is high.

In the above-described embodiment of the present invention, a pretensioner for a seat belt is described as an example. However, the above-described system configuration can be applied to an airbag inflated by a seat. That is.

[0020]

As described above, according to the present invention, the collision from the pressure-sensitive sensor based on the required time calculated when there is a high possibility that the own vehicle collides with an object ahead in the traveling direction of the own vehicle. Set a predetermined time range that can detect the signal, and when the collision signal is generated in the pressure sensitive sensor within this predetermined time range, the safety device is activated, so in the case of mild contact that does not lead to a collision accident The actuation of the safety device is avoided and the safety device will be activated when it is really needed.

[Brief description of the drawings]

FIG. 1 is a diagram corresponding to claims of the present invention.

FIG. 2 is a block diagram illustrating a system configuration of a seatbelt pretensioner device according to an embodiment to which the vehicle occupant protection device of the present invention is applied.

FIG. 3 is a diagram illustrating a configuration of a pressure-sensitive sensor.

FIG. 4 is a diagram showing an operation principle of a pressurized conductive rubber which is a main part of the pressure-sensitive sensor.

FIG. 5 is a diagram illustrating a configuration of a seat belt pretensioner main body.

FIG. 6 is a flowchart showing an operation flow of the seat belt pretensioner device according to one embodiment of the present invention.

FIG. 7 is a timing chart showing a relationship between a predetermined time region after abnormal approach prediction and an output of the pressure-sensitive sensor.

FIG. 8 is a timing chart showing a relationship between a pressure-sensitive sensor output and a threshold level.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Distance sensor 2 Pressure sensor 3, 3A Safety device 4 Control part (CPU) 5 Relative speed calculation means 6 Judgment means 7 Collision time calculation means 8 Setting means 9 Safety control means

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int. Cl. ⁷ , DB name) B60R 21/00 624 B60R 21/00 610 B60R 21/16-21/32 B60R 22/46

Claims (4)

(57) [Claims] A distance sensor for detecting a distance from the host vehicle to an object in front of the host vehicle; a pressure sensor provided at a front end of the vehicle for detecting contact with the object ; A safety device for protecting an occupant; and a distance to the object detected by the distance sensor .
Based on the amount of change per unit time, relative speed calculation means for calculating the relative speed between the vehicle and the object, the distance to the object detected by the distance sensor,
Based on the relative speed calculated by the relative speed calculating means.
Determining means for determining whether the own vehicle collides with the object; and determining that the own vehicle collides with the object by the determining means.
If the distance is detected, the distance detected by the distance sensor
Separation and relative speed calculated by the relative speed calculating means.
Based on the degree, based on the collision time calculation means, a required time calculated by the collision time calculation means for calculating a time required for the own vehicle collides with the object
As standard, setting means for setting a predetermined time area, and safety control means for operating the safety device when contact of an object is detected by the pressure-sensitive sensor within the time area set by the setting means. An occupant protection device for a vehicle, comprising: 2. The vehicle occupant protection device according to claim 1, wherein said pressure-sensitive sensor is a pressure-sensitive rubber switch stuck linearly along the inside of the vehicle bumper. 3. The vehicle occupant protection device according to claim 1, wherein the safety device is a seat belt pretensioner that is wound by the control unit. 4. The occupant protection system for a vehicle according to claim 1, wherein the safety device is an airbag inflated by a seat.