JPH08216826A - Hood air bag sensor system - Google Patents

Abstract

PURPOSE: To certainly expand a hood air bag at the time of collision with a pedestrian as well as to prevent expansion of the hood air bag at the time of collision with other than a pedestrian. CONSTITUTION: A hood air bag 13 is expanded on a hood 12 when a bumper sensor 16 is switched on at the time of collision with a pedestrian and a hood sensor 17 is switched on by a load in the vertical direction by the pedestrian falling down on a front part of the hood 12 by setting the bumper sensor 16 to detect a load from the front substantially in the horizontal direction and the hood sensor 17 to detect a load from above substantially in the vertical direction. Additionally, in the case when the load from above in the vertical direction is not applied on the hood sensor 17 as in the case of colliding against a building, etc., the hood sensor is not switched on, and accordingly, the hood air bag 13 is not expanded.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a collision sensor for a hood airbag device which protects a pedestrian by deploying an airbag on the hood when the vehicle collides with a pedestrian. The present invention relates to a hood airbag sensor system that can detect a collision with a person other than a pedestrian separately.

[0002]

2. Description of the Related Art When a running vehicle collides with a pedestrian, the collided pedestrian is either bounced up by the difference in vehicle speed at the time of collision or the lower half of the body is swept away by the front part of the vehicle body and It is known that a secondary collision will occur on the hood, etc., and in order to absorb the impact when a pedestrian makes a secondary collision on the hood, etc., an airbag is deployed on the hood, etc. It has been proposed to protect the pedestrian by absorbing the impact of a secondary collision with the upper surface of the hood.

FIG. 9 and FIG. 10 show an actual flat plate 6-7453.
3 shows a conventional pedestrian protection airbag device disclosed in Japanese Patent Publication No. 3), which is located near the lower portion of the windshield 2 which is a highly rigid portion on the upper front surface of the vehicle body of the vehicle 1 and the straddle. The airbag 4 is housed together with the inflator 5 in three places, that is, the left and right fenders 3, 3 above the tower, and the contact detection sensor 7 provided in the front bumper 6 at the front of the main body is connected to the pedestrian H. When the contact is sensed and a sensing signal is issued, the airbags 4 housed in the three locations are inflated and deployed to protect a pedestrian who makes a secondary collision with the upper surface of the front of the vehicle body.

[0004]

Therefore, in the above-described conventional pedestrian protection airbag device, the contact detection sensor 7 provided on the front bumper 6 at the front end of the vehicle body when traveling at a predetermined vehicle speed or higher. When any object comes into contact with, the sensor 7 that senses the contact outputs a sensing signal to inflate and deploy the airbag 14 without fail. Therefore, even if the vehicle does not collide with a pedestrian, if there is something that comes into contact and turns on the contact detection sensor 7, it does not need protection by an airbag such as a building, a utility pole, or a guardrail. Even
There is a disadvantage that the airbag 14 is inflated and deployed automatically.

The present invention has been made in view of the above circumstances, and detects a collision with a pedestrian separately from a collision with a non-pedestrian, so that a signal is output only in the case of a collision with a pedestrian. It is an object of the present invention to provide a hood airbag sensor system that inflates an airbag.

[0006]

As a means for solving the above problems, the present invention is installed near the front end of a vehicle and deploys an airbag on the hood of the vehicle when a collision with a pedestrian is detected. In the hood airbag sensor system that outputs a signal as described above, a first sensor attached to the front end of the vehicle to detect a load from the front in the substantially horizontal direction, and a load arranged near the front end of the vehicle from above in the substantially vertical direction And a second sensor that detects a load. When both the first sensor and the second sensor detect a load, a signal is output to deploy the airbag.

Further, after the load is detected by the first sensor, the signal can be output only when the load is detected by the second sensor to deploy the airbag.

[0008]

[Function] A pedestrian who collides with a running vehicle first comes into contact with the front bumper at the front end of the vehicle and is scooped down to fall on the hood at the front of the vehicle body. Clash with. Therefore, the hood airbag sensor that detects a collision is composed of two sensors, a first sensor that detects a load from a substantially horizontal front side and a second sensor that detects a load from a substantially vertical direction above, and the first sensor When the sensor detects the load from the front in the substantially horizontal direction and the load from the top in the substantially vertical direction by the second sensor, a signal is output to inflate and deploy the airbag. Moreover, even if the first sensor detects the load,
If the second sensor does not detect the load, that is, if it collides with something other than a pedestrian, the airbag is not deployed.

Further, it is also possible to output a signal only when the second sensor detects the load after the first sensor detects the load to inflate and deploy the airbag. In this case, even if the first sensor detects the load after the second sensor detects the load first, no signal is output, and therefore the airbag does not deploy due to a collision with something other than a pedestrian.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the hood airbag sensor system of the present invention will be described below with reference to FIGS.

In the hood airbag sensor system of the present invention, the hood 12 is detected by the hood airbag sensor 11 only when it collides with a pedestrian H when the vehicle is traveling.
In this system, the hood airbag 13 is deployed on the top and the hood airbag 13 is not deployed when a collision with a person other than a pedestrian occurs.

The hood airbag sensor 11 is provided near the front end of the vehicle body of the vehicle 14 and is a first sensor attached to the front banmbar 15 which is the bumper sensor 1.
6, a hood 12, and a hood sensor 17, which is a second sensor, arranged between the vehicle body and two sensors.

When the bumper sensor 16 is compressed by a load applied in the horizontal direction from the front side, the bumper sensor 16 conducts to detect a detection signal and performs a sequence control or the like.
As shown in FIG. 3, the pressure-conducting rubber 16a is formed by kneading fine metal particles into a silicon rubber band.
2 is sandwiched between two electrodes 16b, 16b made of a flat braided copper wire bundle from both sides, and the outside thereof is integrally covered with silicone rubber 16c to form a long length. As shown in FIG. Bumping horse 1 inside
The electrodes 16b and 16b and the pressure conductive rubber 16a are laminated in the vehicle front-rear direction between the bumper foam 15b which is a cushioning material attached to the front side of the 5a and the bumper skin 15c which covers the outside of the bumper foam 15b. In the state
It is provided over substantially the entire length of the front bumper 15.
When a load is applied to a part of the front bumper 15 from the front side of the vehicle in the horizontal direction, the pressure conductive rubber 16a is compressed between the electrodes 16b and 16b to obtain conductivity, whereby the electrodes 16b and 16b are electrically conductive. Is turned on, the bumper sensor 16 is turned on, and a detection signal is sent to the control device 18.

Further, the hood sensor 17 conducts when it is compressed by a load inputted from above in the vertical direction and sends a detection signal to the control device 18. As shown in FIG. The pressure conductive rubber 17a, which is formed of rubber in the shape of a disk, is connected to the two electrodes 17b in the shape of a disk.
It is sandwiched from both sides by 17b, and the outer side thereof is integrally covered with silicone rubber 17c to form a waterproof columnar shape. As shown in FIG. The pair of hood cushions 19 (one of which is omitted) attached to each of the 12a is attached to the inner side of the vehicle body, on the upper end surface of the radiator support 20 on the vehicle body side so as to face the lower surface of the hood inner 12a. The rubber 17a and the electrodes 16b and 16b are installed in a vertically stacked state.

When a load is applied to the front end side of the hood 12 from above in the vertical direction and the hood cushion 19 is compressed or the hood 12 is deformed downward, the hood provided below the hood 12 is compressed. The inner 12a
Upper protrusion 17d of the hood sensor 17 fixed to the vehicle body side
Is pressed downward in the vertical direction. The compressed conductive rubber 17a that has been compressed obtains conductivity, so that both electrodes 1
The hood sensor 17 is turned on by connecting 7b and 17b, and a detection signal is sent to the control device 18.

Then, the control device 18 controls the bumper sensor 16
When the detection signal from the hood sensor 17 is inputted after receiving the detection signal from the hood air bag 13, the hood air bag 13 in which the hood air bag 13 and an inflator (not shown) for generating gas for inflating the hood air bag 13 are integrally attached. Bag module 2
The inflator 1 is wired and connected so as to flow an ignition current. In FIG. 5, reference numeral 17e is a waterproof cap for fastening and fixing the hood sensor 17, and 17f is a lead wire.

Next, the operation of this embodiment configured as described above will be described.

When the running vehicle 14 collides with a pedestrian, first, the lower half of the pedestrian H comes into contact with the front bumper 15 at the front end of the vehicle body so that the bumper sensor 16 receives a load from the front in the horizontal direction (see FIG. 6), the bumper sensor 16 is turned on and outputs a detection signal. Next, the pedestrian H who has come into contact with the front bumper 15 and whose lower half of the body is washed away falls down on the hood 12 in the front part of the vehicle body. As a result, a downward load is applied and the front portion of the hood 12 is pushed downward, so that the hood inner 12a also moves downward and the upper protrusion 17d of the hood sensor 17 is vertically loaded (from the arrow in FIG. 6). (Load in the B direction) is applied, and this hood sensor 17
Turns on and outputs a detection signal. At this time, the control device 1
In 8, the control shown in the flowchart of FIG. 8 is performed.

In step 1, it is determined whether the bumper sensor 16 is on, that is, whether the bumper sensor 16 outputs a detection signal. If the bumper sensor 16 outputs a detection signal, step 2 Then, it is determined whether or not the detection signal is output from the hood sensor 17. When the detection signal is output from the hood sensor 17, the process proceeds to step 3 and the ignition signal is transmitted to the inflator.

Thus, in the case of a collision with a pedestrian,
Ignition current flows through the inflator of the hood airbag module 21 to ignite the gas generating agent in the inflator, and the generated gas causes the hood airbag 13 to instantly expand and deploy on the hood 12. Therefore, the hood 1
The pedestrian H who has fallen over 2 is absorbed by the collision of the head and upper body with the hood airbag 13 deployed on the hood 12, and is effectively protected from a secondary collision with the upper surface of the hood 12. It

On the other hand, when the running vehicle 14 collides with a building K other than a pedestrian, for example, the bumper sensor 16 is first compressed by the load from the front in the horizontal direction (the load in the direction of arrow A in FIG. 7). However, even if a collision is detected and a detection signal is output, a load that presses the hood 12 downward does not occur, so the hood sensor 17 that detects the load chisel from above in the vertical direction cannot detect the load, and therefore the hood is not detected. No detection signal is transmitted from the sensor 17.

That is, even if it is determined in step 1 of the flowchart of FIG. 8 that the detection signal is output from the bumper sensor 16 and the process proceeds to step 2, if the detection signal from the hood sensor 17 is not received in step 2 Return to step 1 and bumper sensor 1 again
It is determined whether 6 is on. Therefore, when a collision occurs with the building K or the like other than a pedestrian, the ignition current does not flow from the control device 18 to the inflator, and as a result, unnecessary deployment of the hood airbag 13 can be prevented.

In this embodiment, a signal is output only when the hood sensor 17 detects the load after the bumper sensor 16 detects the load, and the hood airbag 13
I explained about the case of expanding and deploying
It is also possible to output the signal and inflate and deploy the hood airbag 13 when both the bamba sensor 16 and the hood sensor 17 detect the load irrespective of the order.

In this embodiment, the pressure-sensitive type sensor is used as the bumper sensor 16, but a contact switch type sensor or the like may be used instead of the pressure-sensitive type sensor. Further, as the hood sensor 17, a case where a pressure-sensitive type sensor is used has been described, but a push switch type sensor or the like can be used instead.

[0025]

As described above, the hood airbag sensor system of the present invention comprises the first sensor for detecting the load from the front in the substantially horizontal direction and the second sensor for detecting the load from the top in the substantially vertical direction. It is composed of two sensors, and when the first sensor and the second sensor both detect a load and output a signal, the airbag is adapted to be deployed,
In the case of a collision with a pedestrian, it is necessary to deploy the airbag on the hood to protect the pedestrian from the impact of a secondary collision on the hood and to deploy the airbag on the hood. In the case of a collision with a person other than a non-pedestrian, the airbag can be reliably prevented from being unnecessarily deployed. In addition, after the first sensor detects the load, the second sensor
By outputting a signal only when the sensor detects a load and inflating and deploying the airbag, it is possible to more accurately prevent accidental explosion of the airbag at the time of collision with a person other than a pedestrian.

[Brief description of drawings]

FIG. 1 is an explanatory diagram showing an installed state of a hood airbag sensor system according to an embodiment of the present invention.

FIG. 2 is a cross-sectional side view of a front bumper showing a mounted state of a bapper sensor.

FIG. 3 is a partially cutaway perspective view showing a structure of a bumper sensor.

FIG. 4 is a sectional front view of a hood portion showing a mounted state of the hood sensor.

FIG. 5 is a partially cutaway perspective view showing the structure of a hood sensor.

FIG. 6 is an explanatory diagram showing a load direction applied at the time of collision with a pedestrian over time.

FIG. 7 is an explanatory diagram showing a load direction applied when a collision occurs with a building.

FIG. 8 is a control flowchart of the hood airbag device.

FIG. 9 is a perspective view of a vehicle equipped with a conventional pedestrian protection airbag device.

FIG. 10 is an explanatory view showing an operating state of the pedestrian protection airbag device.

[Explanation of symbols]

 11 Hood Airbag Sensor 12 Hood 13 Hood Airbag 14 Vehicle 15 Front Bumper 16 Bumper Sensor (First Sensor) 16a Pressurized Conductive Rubber 16b Electrode 17 Hood Sensor (Second Sensor) 18 Control Device 20 Radiator Support 21 Hood Airbag Module H Pedestrian K building

Claims (2)

[Claims] 1. A hood airbag sensor system which is installed near a front end of a vehicle and outputs a signal to deploy an airbag on a hood of a vehicle when a collision with a pedestrian is detected. A first sensor for detecting a load from substantially the front in the substantially horizontal direction, and a second sensor arranged near the front end of the vehicle for detecting a load from the substantially vertical direction from above, the first sensor and the second sensor. A hood airbag sensor system, wherein the sensor and the sensor both output a signal when the load is detected to deploy the airbag. 2. A signal is output only when the second sensor detects a load after the first sensor detects the load,
The inflatable air bag is inflated.
The described hood airbag sensor system.