JPH04368252A - Collision sensor - Google Patents

Abstract

PURPOSE:To improve the sensor sensitivity and to keep off any unnecessary inflation of an air bag. CONSTITUTION:In a collision sensor consisting of plural pieces of primary sensors 17 set up at specified sensibility and a secondary sensor 16 being turned to ON after being held, under pressure, by large force of more than specified value, it detects a collision in the case where the secondary sensor 16 is turned to ON irrespective of ON or OFF of these primary sensors 17, or each ON signal out of these primary sensors 17 has satisfied the preset condition, thereby outputting such a signal as inflating an air bag.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a collision sensor that detects a vehicle collision and outputs a signal to inflate an air bag to protect occupants from a secondary collision.

0002

BACKGROUND OF THE INVENTION Airbags, which are deployed to protect occupants in the event of a frontal or side collision, are inflated by inert gas generated by an inflator that is part of an airbag device. In an electric airbag device, a gas generating agent inside the inflator is ignited by a signal output when a collision sensor installed in a predetermined part of the vehicle body detects a collision, and a large amount of gas is instantaneously generated to blow into the airbag. The liquid rapidly fills the interior of the vehicle and expands instantly, and is deployed between the driver and the steering wheel, between the front passenger and the dashboard, or between each passenger and the inside wall of the vehicle interior, such as the inner surface of the side door. to protect occupants from secondary collisions.

[0003] Therefore, in the case of a side collision where the amount of impact absorption by the car body structure is small, the inflator must be inflated in an extremely short period of time, so a highly sensitive collision sensor is installed at the location on the car body where it can detect a collision fastest. There is a need.

For example, FIG. 10 shows an example of a conventional side collision airbag device, which is described in US Pat. It is attached to the inside of the outer panel 3 of the door 2 or to the flat plate 4 arranged inside the side door 2. The collision sensor 1 is a contact-type or pressure-sensitive type sensor that detects a side collision by being compressed together with the attached members at the time of a vehicle collision. When a side collision is detected, it outputs a signal to the inflator 5. The inflator 5 that receives the signal is ignited, and a large amount of gas is generated to inflate the airbag 6 and deploy it between the occupant D and the inner surface of the side door 2, thereby protecting the occupant from a secondary collision.

As described above, in the case of the conventional side collision sensor 1, it is installed at a location where side collisions can be easily detected, such as the inner surface of the outer panel 3 of the side door 2 of the vehicle, and the side door 2 is The load associated with the deformation causes, for example, a pair of contacts to conduct, outputting a signal to inflate the airbag.

[0006]

[Problems to be Solved by the Invention] By the way, the aspects of a vehicle side collision include collisions of the vehicle from an almost right angle direction, collisions from an oblique direction at a certain angle, and local collisions with obstacles such as utility poles. A collision is considered, and the manner in which the collision load is applied differs depending on the type of collision. for example,
If the front part of another vehicle collides with the side door at a nearly right angle, the area on which the load is applied becomes wider and the load per unit area becomes smaller.Also, if the side door collides with a thin obstacle such as a telephone pole In this case, the area on which the load is applied is small, and even if the total load is small, the load per unit area is large. The collision sensor 1 of the side collision airbag device described above must be able to accurately detect the various types of collisions described above, so the highly sensitive sensor 1 is installed at the side door 2.
The structure is generally such that it is attached to a location where a side collision can be relatively easily detected, such as the inner surface of the outer panel 3 or the filler 5 inside the door.

However, the higher the sensitivity of the sensor, the more accurately it can detect a collision, but on the other hand, it is activated even by a slight impact other than a collision, so when the side door is opened, There is also the problem that the sensor may malfunction if the vehicle is hit by a nearby structure or the side door is kicked.

The present invention was made in view of the above circumstances, and an object of the present invention is to provide a collision sensor that can detect collisions with high sensitivity and prevent malfunctions.

[0009]

[Means for Solving the Problems] As a means for solving the above problems, the present invention provides a collision sensor that outputs a signal to inflate an airbag device when a collision is detected, and a plurality of collision sensors are provided at predetermined intervals. It consists of a primary sensor that is pressed and turned ON by a relatively small force, and a secondary sensor that is pressed and turned ON by a certain force greater than the force that turns the primary sensor ON. The secondary sensor is turned on regardless of the O from the primary sensor.
It is characterized in that a collision is detected and the signal is output when the N signal satisfies a preset condition.

0010

[Operation] As mentioned above, this collision sensor is provided in plural at predetermined intervals, and includes a primary sensor that turns ON when pressed with a relatively small force, and a secondary sensor that turns ON when pressed with a larger force. When a relatively small force is locally input, a collision is not detected because only one primary sensor is turned on, or because the number of primary sensors turned on is small, the signal to ignite the inflator etc. is not detected. No output. Furthermore, when the vehicle collides with a utility pole or the like, a large force is input in a small area, so the secondary sensor is turned on to detect the collision and output a signal to inflate the airbag. In addition, even if the force is relatively small, if the force is applied over a wide range beyond a certain level, the secondary sensor will not turn on, but multiple primary sensors will turn on, and if this ON signal satisfies the predetermined conditions. A collision is detected and a signal is output to inflate the airbag.

[0011]

[Example] An example in which the collision sensor of the present invention is applied to a collision sensor for a side collision airbag device will be described below with reference to FIG.
This will be explained based on FIGS.

The airbag of the side collision airbag device is housed in a side door or an armrest on the passenger compartment side (not shown), and when the collision sensor 11 detects a side collision, the airbag (not shown) A signal is output to ignite the inflator. This collision sensor 1
As shown in FIG. 2, between the outer panel 13 of the side door 12 and a side door beam 14 provided almost horizontally just inside this outer panel 13, the side door beam 14 is integrally provided with a spacer 15 interposed therebetween. installed. Then, as shown in FIG. 1, this collision sensor 1
1 is a long secondary sensor 16 in the shape of a thin rectangular pipe, and a primary sensor 17 in the form of a short cut of a thin rectangular pipe with almost the same cross-sectional shape and low rigidity.
Primary sensors 17 are attached at regular intervals to the outer surface of a long secondary sensor 16 that is attached to a highly rigid side door beam 14 with a circular cross section via a spacer 15. 17
A slight space is formed between and the outer panel 13, as shown in FIG. Therefore, the elongated secondary sensor 16 having a certain degree of rigidity is attached to the side beam 1.
4, so the side door beam 14
The weight can be reduced.

Further, the primary sensor 17 is a highly sensitive sensor of a type that is crushed even if it is squeezed with a relatively small force, and for example, contacts (not shown) disposed facing each other on the inside become conductive and turn on. Yes, and the secondary sensor 16 is
When the primary sensor 17 is squeezed with a force greater than a certain level, which is greater than the force that turns the primary sensor 17 ON, it is crushed in the same way, and the contacts (not shown) become conductive and turn ON, making it a slightly less sensitive sensor.
This primary sensor 17 is attached to overlap the secondary sensor 16.

[0014]The installation of this collision sensor 11 is as follows:
For example, as shown in FIG. 2, it is already placed inside the side door. It is attached to the side door beam 14 in a non-rotatable manner by a spacer 15 in advance, and is in this state (the state shown in FIG. 1).
It is inserted into the door through the opening 19 formed in the inner panel 18 of the side door 12, and the collision sensor 11 is placed on the outer panel 13 side so that both ends of the side door beam 14 are installed on both sides of the side door. It is bolted to a strength member located approximately horizontally. The collision sensor 11 outputs or does not output a collision detection signal depending on the ON/OFF state of the primary sensor 17 and the secondary sensor 16, and is equipped with a control device C as a means for that purpose. Sensor 17 and secondary sensor 16 are each connected to this control device C. The ON/OFF combinations of the sensors 17 and 16 that output collision detection signals are shown in FIG.
This is as shown in the map, and this will become clear from the operation of this embodiment described below.

In this embodiment, the collision sensor 11 is attached to the side door beam 14 having a circular cross section through the spacer 15. A lightweight and highly rigid side door beam 24 such as an extruded aluminum alloy material may also be used. In this case, the spacer 15 is not necessary, and the primary sensor 1 is placed on one side of the side door beam 24 on the outer panel 13 side.
7 and a secondary sensor 16 are directly attached. In addition, since the collision sensor 11 is attached to the side door beams 14 and 24 which have high rigidity, the primary sensor 17 and the secondary sensor 16 of the collision sensor 11 are crushed before the side door beams 14 and 24 are deformed in the event of a collision. Side collisions can be detected faster.

Next, the operation of this embodiment constructed as described above will be explained based on FIGS. 6 to 9.

As shown in FIG. 6, the collision sensor 11 installed in the side door 12 as described above is configured to prevent the vehicle A from accidentally touching the side door 12 with a sign when the vehicle A opens the side door 12 in a parking lot or the like. When the door hits a pole 25 such as a support, the secondary sensor 16 remains OFF because the door is partially compressed with a relatively small force. Also,
Since the diameter of the collided pole 25 is not very large, at most only one highly sensitive primary sensor 17 is turned on, and two or more are not turned on, so the collision is not detected (aspect (II) in Fig. 5). ). Therefore, a signal to inflate the airbag is not output, and the airbag does not need to be inflated.

Further, as shown in FIG. 7, when the vehicle A spins or skids while traveling and collides with a utility pole 26 or the like from the side, the load per unit area increases, so at least the secondary sensor 16 is turned on. In this case, depending on the location where the load is applied, either one of the primary sensors 17 is turned on or none of the primary sensors 17 is turned on (aspect (IV) in FIG. 5). As a result, a signal to inflate the airbag is output, the inflator is ignited, and the airbag (not shown) housed in the armrest etc. is instantly inflated by a large amount of inert gas generated by the inflator, causing the vehicle to It can be deployed between an indoor occupant and the side door 12 to protect the occupant from a secondary collision.

Further, as shown in FIG. 8, when another vehicle 27 collides with the running vehicle A from the side, the bumper of the other vehicle 27 collides with a wide area of the side of the vehicle A, so that the energy of the collision is reduced. The plurality of primary sensors 17 are crushed by the distributed load and turned ON, and as a result, a side collision is detected before the secondary sensor 16 is crushed and turned ON (aspect (III) in FIG. 5).

Further, as shown in FIG. 9, a parked vehicle A
When an external force 28 is locally applied to the vicinity of the side door by a prank such as being kicked from the outside, the highly sensitive primary sensor 17 is turned on by the locally applied force, as in the case of FIG. , the secondary sensor 16 is O
Only one primary sensor 17 remains FF and turns ON when external force 28 is applied locally.
Since the preset conditions are not met, a collision will not be detected and the airbag will not inflate. (Aspect II in FIG. 5).

[0021] In the above embodiment, the case where the collision sensor is attached to the side door beam has been explained.
It is also possible to attach it to other members, and relatively rigid members such as dent beams and reinforcement materials are suitable for attachment. Furthermore, although this embodiment has been described in the case where it is applied as a collision sensor for an airbag device for a side collision, it can also be used as a collision sensor for an airbag device that is deployed in the event of a frontal collision. Furthermore, although the case has been described in which the primary sensor 17 and the secondary sensor 16, whose contacts are electrically connected when crushed during a collision, are used as the collision sensor 11, other types of sensors may also be used, and sensors of different types may be combined. They can also be used together.

Furthermore, in the above embodiment, the condition for detecting a collision is the ON signal from two or more primary sensors, but the present invention is not limited to this. For example, when three or more primary sensors or every other sensor are ON, a collision is detected. It may also be set as a detection condition.

[0023]

As explained above, the collision sensor of the present invention includes a plurality of primary sensors provided at predetermined intervals, and a secondary sensor that is turned on by being pinched with a force greater than a certain level that is greater than the force that turns the primary sensor on. When the secondary sensor is turned ON regardless of whether the primary sensor is ON or OFF, or when the ON signal from the primary sensor satisfies a preset condition, it detects a collision and outputs the signal. A side collision of a vehicle can be clearly distinguished from a side load caused by other reasons, and therefore malfunction of the airbag device can be prevented, and responsiveness to the impact that inflates the airbag can be improved.

[Brief explanation of drawings]

FIG. 1 is a perspective view showing a state in which a collision sensor of the present invention is attached to a side door beam.

FIG. 2 is a partially cutaway perspective view of a side door showing a collision sensor arrangement structure.

FIG. 3 is a sectional view showing the arrangement of collision sensors.

FIG. 4 is a diagram showing how a collision sensor is attached to another side door beam.

FIG. 5 is a map showing ON/OFF states of sensors depending on different types of collisions.

FIG. 6 is an explanatory diagram showing ON/OFF of a sensor when the side door hits a pole when opening it.

[Figure 7] Sensor ON/Off in case of side collision with utility pole
It is an explanatory view showing F.

[Figure 8] Sensor ON/OFF in case of side collision with another vehicle
It is an explanatory view showing OFF.

[Figure 9] Sensor ON/Off when the side of the vehicle is kicked
It is an explanatory view showing F.

FIG. 10 is an explanatory diagram showing the arrangement of collision sensors of a conventional side collision airbag.

[Explanation of symbols]

11 Collision sensor 12 Side door 13 Outer panel 14 Side door beam 15 Spacer 16 Secondary sensor 17 Primary sensor 18 Inner panel 19 Opening 24 Side door beam with H-shaped cross section 25 Paul 26 Telephone pole 27 Other vehicles 28 External force A Vehicle C Control device

Claims (1)

[Claims] Claim 1: A collision sensor that outputs a signal to inflate an airbag device when a collision is detected, comprising a plurality of primary sensors provided at predetermined intervals and turned ON by being compressed with a relatively small force; and a secondary sensor that is turned ON by being pressed with a force greater than a certain level, which is greater than the force that turns the primary sensor ON, and the secondary sensor is turned ON regardless of whether the primary sensor is ON or OFF, or the ON signal from the primary sensor is turned ON. A collision sensor that detects a collision and outputs the signal when a preset condition is satisfied.