JP2932007B2 - Collision judgment circuit - 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 judging circuit for outputting a start signal for activating an airbag device or a belt retractor at the time of a vehicle collision.

[0002]

2. Description of the Related Art In an airbag device for protecting an occupant from a secondary collision during a vehicle collision, if only an acceleration signal output from an acceleration sensor is used as a starting signal of the airbag device, the vehicle body is hardly damaged. There is a possibility that a start signal may be output only when a small object collides with the vicinity of the acceleration sensor, and a means for preventing the start signal is required. Further, it is necessary to operate the airbag device not only in the case of a collision having a large impact but also in the case of a collision having a small impact and continuing for a long time. In such a case, the acceleration sensor does not output a start signal. Because of the possibility, means to compensate for it are needed.

In order to avoid such a problem, the speed calculated by integrating the acceleration output by the acceleration sensor, that is, the vehicle speed at which the occupant approaches the steering wheel, for example, is calculated based on the inertia due to the collision, and the vehicle speed is calculated. A device that outputs an activation signal of an airbag device when the speed exceeds a predetermined reference value has been proposed (see Japanese Patent Publication No. 59-8574 ).

[0004]

SUMMARY OF THE INVENTION The present invention further improves a method of outputting an activation signal for an airbag device or the like based on the above-mentioned anti-vehicle speed, and more accurately activates in response to various collision states. An object of the present invention is to provide a collision determination circuit capable of outputting a signal.

[0005]

In order to achieve the above object, the present invention relates to a collision judging circuit for outputting a starting signal based on an output signal of an acceleration sensor for detecting acceleration generated by a vehicle collision. First integration means for integrating the output signal of the acceleration sensor to calculate the vehicle speed of the occupant; second integration means for calculating the stroke of the occupant by integrating the vehicle speed; Determining means for outputting a start signal based on an anti-vehicle stroke ;
The determining means determines that the anti-vehicle speed is high when the anti-vehicle speed is high.
The stroke is small and the occupant and the steering wheel
It characterized the this <br/> which outputs an activation signal even when relatively there is enough distance.

[0006]

Embodiments of the present invention will be described below with reference to the drawings.

As shown in FIG. 1, a battery 1 and a ground 2
A mechanical acceleration sensor 3, a squib 4, and a transistor 5 are arranged in series between the two. The mechanical acceleration sensor 3 detects an acceleration generated by a collision of the vehicle, and closes a contact to operate the airbag device when the detected acceleration exceeds a predetermined value. Squibb 4
The propellant for energizing the battery 1 to deploy the airbag when the contact of the mechanical acceleration sensor 3 is closed and the collision determination circuit 6 described later outputs a start signal to the base of the transistor 5 Ignite.

Reference numeral 7 denotes an electric acceleration sensor, which converts an acceleration generated by a vehicle collision into an electric signal, that is, a voltage signal by a strain gauge and continuously outputs the electric signal. After the output signal of the electric acceleration sensor 7 is amplified by the amplifier 8, it is input to the first integration means 9 provided in the collision determination circuit 6.

The first integration means 9 is constituted by an integration circuit, and has a function of calculating the anti-vehicle speed ΔV after the collision by integrating the acceleration. The anti-vehicle speed ΔV corresponds to the speed at which an occupant without a seatbelt is thrown toward the front of the vehicle by inertia at the time of a collision, and its value is determined by the magnitude of the acceleration due to the collision and the elapsed time after the collision. Is done.

The second integrating means 10 is also constituted by an integrating circuit, and the vehicle speed ΔV output by the first integrating means 9 is also used.
Is further integrated to calculate the anti-vehicle stroke ΔS after the collision. This anti-vehicle stroke ΔS corresponds to the distance that the occupant is thrown from the seat to the front of the vehicle body,
The value is determined by the magnitude of the acceleration due to the collision and the elapsed time after the collision, as in the case of the anti-vehicle speed ΔV.

The output signals of the first integration means 9 and the second integration means 10 are input to the judgment means 11, where the output signals of FIG.
An activation signal of the airbag device is output to the transistor 5 based on the map shown in FIG. That is, the values of the vehicle speed ΔV and the vehicle stroke ΔS in FIG.
The start signal is not output when in the FF region, and is output when in the ON region above the curve.

Next, the operation of the present invention having the above-described configuration will be described. When acceleration occurs due to a vehicle collision, the contact point of the mechanical acceleration sensor 3 that detects the acceleration is closed. At this time, when the collision judging circuit 6 does not output the start signal, the squib 4 does not operate because the transistor 5 does not conduct.

The voltage signal output from the electric acceleration sensor 7 based on the acceleration due to the collision is amplified by the amplifier 8 and input to the first integrator 9 of the collision judging circuit 6, where it is integrated to obtain the vehicle speed. ΔV is calculated. The anti-vehicle speed ΔV is input to the judging means 11 and also to the second integrating means 10, where the anti-vehicle stroke ΔS calculated by integrating the anti-vehicle speed ΔV is input to the judging means 11.

In the judging means 11, the values of the vehicle speed ΔV and the vehicle stroke ΔS are compared with the map shown in FIG. 2. At this time, if the vehicle speed ΔV is high, that is, if the occupant is, for example, the steering wheel If the speed of approaching the vehicle is high, an activation signal is output even if the anti-vehicle stroke ΔS is small and the distance between the occupant and the steering wheel is relatively large. On the other hand, the vehicle speed ΔV
Is small, that is, even if the speed at which the occupant approaches the steering wheel is low, a start signal is output if the vehicle stroke ΔS is large and the occupant is close to the steering wheel. . When the start signal is output in this manner, the transistor 5 is turned on and a current flows through the squib 4, and the airbag device operates to restrain the occupant.

By outputting the activation signal of the airbag device in consideration of both the vehicle speed ΔV and the vehicle stroke ΔS of the occupant, various collisions having different magnitudes and durations of acceleration can be performed. On the other hand, it is possible to reliably operate the airbag device.

Although the embodiments of the present invention have been described in detail, the present invention is not limited to the above embodiments, and various small design changes can be made without departing from the present invention described in the appended claims. It can be carried out.

For example, the present invention can be applied not only to an airbag device but also to a seat belt retraction device.

[0018]

According to the present invention as described above, according to the present invention, and outputs the Taikuruma speed obtained by integrating the acceleration generated by the collision of the vehicle, an activation signal based on the Taikuruma strokes further integrating the pair car speed Especially when the vehicle speed is high,
The troke is small and the distance between the occupant and the steering wheel
Even if there is relatively room for separation,
Since the output is performed, the airbag device and the belt retracting device can be reliably operated without waste according to both the actual relative speed and the relative distance between the occupant and the vehicle body. Can accurately cope with various different collisions. Moreover, since the collision is determined based on the relative movement of the occupant with respect to the vehicle body, the same determination logic can be applied to various vehicles having different strengths, and the versatility is improved.

[Brief description of the drawings]

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

FIG. 2 is a map serving as a reference for output of a start signal

[Explanation of symbols]

 7 ··· Electric acceleration sensor (acceleration sensor) 9 ··· First integration means 10 ··· Second integration means 11 ··· Judgment means ΔV ··· Vehicle speed ΔS ··· Vehicle stroke

Continuation of front page (56) References JP-A-4-146850 (JP, A) JP-A-4-191149 (JP, A) JP-A-4-191145 (JP, A) JP-A-4-146848 (JP) JP-A-4-146849 (JP, A) JP-A-4-146851 (JP, A) JP-A-4-191146 (JP, A) JP-A-4-191147 (JP, A) JP-A-4-191148 (JP, A) JP-A-4-191151 (JP, A) JP-A-4-191144 (JP, A) JP-A-49-55031 (JP, A) JP-A-4-252575 (JP, A) A) (58) Field surveyed (Int. Cl. ⁶ , DB name) B60R 21/16-21/32

Claims (1)

(57) [Claims] 1. A collision determination circuit for outputting a start signal based on an output signal of an acceleration sensor detecting an acceleration generated by a collision of a vehicle, wherein the occupant integrates the output signal of the acceleration sensor. A first integrating means (9) for calculating the vehicle speed (ΔV) of the vehicle, and integrating the vehicle speed (ΔV) to calculate the vehicle stroke (ΔV) of the occupant.
A second integration means for calculating the S) (10), and a determination means (11) for outputting a start signal on the basis of said pair car speed ([Delta] V) and Taikuruma stroke ([Delta] S), the determination means
(11) When the anti-vehicle speed (ΔV) is large,
The anti-vehicle stroke (ΔS) is small,
Start even if there is a comparatively long distance from the steering wheel
A collision judging circuit for outputting a signal .