JP6933934B2 - Pedestrian protection airbag device - Google Patents

Description

The present invention relates to a pedestrian protection airbag device, and more particularly to a pedestrian protection airbag device capable of stabilizing the expansion and deployment shape of the airbag.

In the pedestrian protection airbag device, when a vehicle such as an automobile collides with a pedestrian or a bicycle, a pedestrian or a occupant such as a bicycle (hereinafter referred to as "pedestrian or the like") causes the pillar (body and roof) of the vehicle. It is an airbag device for absorbing the impact when colliding with the pillars that connect the bicycles.

For example, Patent Document 1 and Patent Document 2 include airbags that are discharged to the outside of the vehicle from between a hood (bonnet) that covers the engine room arranged in front of the vehicle and a windshield and cover a pair of front pillars. A pedestrian protection airbag device is disclosed.

Japanese Unexamined Patent Publication No. 2016-011097 Japanese Unexamined Patent Publication No. 2016-07833

The pedestrian protection airbag device described in Patent Document 1 has a configuration in which the airbag is expanded and deployed from the lower surface of the hood toward the windshield, and the impact of the expanded and deployed airbag on the windshield is large. There's a problem.

On the other hand, the pedestrian protection airbag device described in Patent Document 2 has a configuration in which the airbag is expanded and deployed substantially upward in the vertical direction, and the airbag cover covering the airbag housed in the case is provided. It is configured so that it can be bent toward the hood when the airbag is expanded and deployed.

In such a pedestrian protection airbag device, although the problem as in Patent Document 1 is unlikely to occur, since the airbag cover is made of resin, the shape when the airbag comes into contact with the hood during expansion and deployment is not stable. There is a problem that the expansion and deployment shape of the airbag is not stable.

The present invention has been devised in view of the above-mentioned problems, and an object of the present invention is to provide a pedestrian protection airbag device capable of stabilizing the expansion and deployment shape of an airbag.

According to the present invention, in a pedestrian protection airbag device provided with an airbag that is discharged to the outside of the vehicle from between a hood arranged in front of the vehicle and a windshield to cover the front pillars, when the airbag is expanded and deployed. A guide cloth is provided between the hood and the expanded airbag, and the guide cloth is composed of a part of a wrapping cloth that holds the folded shape of the airbag, and is formed on the windshield side. Provided is a pedestrian protection airbag device characterized in that a planned breakage portion is formed in a lower portion.

Further, the pedestrian protection airbag device includes an airbag cover that covers the airbag before expansion and deployment, and the airbag cover is configured to open toward the windshield side when the airbag is expanded and deployed. May be good.

Further, the airbag cover may be configured to expand and deploy the airbag in a substantially vertical direction at an initial stage of expansion and deployment of the airbag.

Further, the width of the guide cloth may be smaller than the width of the airbag cover.

According to the pedestrian protection airbag device according to the present invention described above, since the guide cloth is arranged between the hood and the expanded and deployed airbag when the airbag is expanded and expanded, the lower surface of the hood is arranged when the airbag is expanded and expanded. The gap formed between the airbag and the airbag cover can be covered with a guide cloth, and the expanded and expanded airbag can be suppressed from slipping into the lower surface of the hood, and the expanded and expanded shape of the airbag can be stabilized. can.

It is a top view which shows the airbag expansion and development state of the pedestrian protection airbag apparatus which concerns on one Embodiment of this invention. It is sectional drawing which shows the state before expansion expansion of an airbag. It is sectional drawing which shows the initial state of expansion expansion of an airbag. It is sectional drawing which shows the completion state of expansion expansion of an airbag. It is sectional drawing which shows the comparative example of the pedestrian protection airbag apparatus. It is sectional drawing which shows the modification of the pedestrian protection airbag device shown in FIG. 1, (A) shows the 1st modification, (B) shows the 2nd modification.

Hereinafter, embodiments of the present invention will be described with reference to FIGS. 1 to 6 (B). Here, FIG. 1 is a plan view showing an airbag expansion / deployment state of the pedestrian protection airbag device according to the embodiment of the present invention. FIG. 2 is a cross-sectional view showing a state of the airbag before expansion and deployment. FIG. 3 is a cross-sectional view showing an initial state of expansion and deployment of the airbag. FIG. 4 is a cross-sectional view showing a completed state of expansion and deployment of the airbag.

As shown in FIGS. 1 to 4, the pedestrian protection airbag device 1 according to the embodiment of the present invention is discharged to the outside of the vehicle from between the hood 2 arranged in front of the vehicle and the windshield 3. An airbag 5 that covers the front pillar 4 is provided, and a guide cloth 6 that is arranged between the hood 2 and the expanded and deployed airbag 5 when the airbag 5 is expanded and deployed is provided. In FIG. 1, for convenience of explanation, the airbag 5 and the guide cloth 6 are shown by a alternate long and short dash line.

As shown in FIG. 2, in a vehicle equipped with a pedestrian protection airbag device 1, a hood 2 (bonnet) covering an engine room or the like is arranged in front of the vehicle, and a windshield 3 is provided behind the hood 2 (bonnet). Have been placed. Further, a cowl 7 may be arranged at the lower end of the windshield 3. Although not shown, the lower end of the windshield 3 is connected to and supported by the vehicle structure.

Further, the hood 2 may be a pop-up type hood 2 that lifts the windshield 3 side of the hood 2 when the vehicle collides with a pedestrian or the like, or may be a hood 2 that does not have such a lifting function. good.

The pedestrian protection airbag device 1 covers the airbag 5, the inflator 11 that supplies the expansion gas to the airbag 5, the retainer 12 to which the airbag 5 and the inflator 11 are fixed, and the airbag 5 before expansion and deployment. It includes an airbag cover 13. Although not shown, the retainer 12 is connected to and supported by the vehicle structure.

The inflator 11 has, for example, a substantially cylindrical shape and is arranged along the lateral width direction of the vehicle. The retainer 12 has a substantially box shape with an open upper end. Inside the retainer 12, the inflator 11 is fixed by a fastener (not shown). Further, inside the retainer 12, the airbag 5 and the guide cloth 6 are fixed by fasteners 14 such as bolts and nuts. At this time, the guide cloth 6 is arranged so that the guide cloth 6 is on the outside of the airbag 5, that is, at the fixed point, the guide cloth 6 is on the lower side of the airbag 5.

The airbag cover 13 has a substantially box shape with an open lower end. Specifically, the airbag cover 13 includes a flat plate portion 13a arranged above the airbag 5 and four side plate portions 13b arranged vertically and horizontally arranged on the back surface of the flat plate portion 13a. ing. In FIG. 1, for convenience of explanation, the airbag cover 13 is shown by a dotted line.

The four side plate portions 13b are arranged so as to extend substantially vertically downward from the flat plate portion 13a, form a space for accommodating the folded airbag 5, and form an expansion / deployment path for the airbag 5. ing. That is, the airbag cover 13 is configured to expand and deploy the airbag 5 in a substantially vertical direction at the initial stage of expansion and deployment of the airbag 5. The retainer 12 is fixed or locked to the lower end of the side plate portion 13b.

The flat plate portion 13a is arranged in an inclined state so that the hood 2 side is high and the windshield 3 side is low. A tear line 13c that opens when the airbag 5 expands and expands is formed on the back surface of the end portion of the flat plate portion 13a on the hood 2 side. That is, the airbag cover 13 is configured to open toward the windshield 3 side when the airbag 5 is expanded and deployed. Further, the end portion of the flat plate portion 13a on the windshield 3 side may be provided with a bent portion 13d that engages with the cowl 7.

For example, as shown in FIG. 1, the airbag 5 has a central expansion portion 51 that expands and expands in the central portion of the hood 2 and the windshield 3, and the airbag 5 projects rearward from both ends of the central expansion portion 51. It is provided with a pair of protruding expansion portions 52 that are expanded and expanded. The protruding expansion portion 52 is formed so as to cover the front pillar 4 of the vehicle.

Further, the airbag 5 is folded inward at both ends and then folded by bellows folding or roll folding so as to fit inside the airbag cover 13. The expanded / expanded shape and the folded shape of the airbag 5 are not limited to the illustrated shapes.

The guide cloth 6 is a sheet having a substantially rectangular shape, and is formed smaller than the width of the airbag cover 13 as shown in FIG. Therefore, when the guide cloth 6 is accommodated, both ends in the left-right direction can be accommodated in the airbag cover 13 without being folded in the left-right direction. By not folding the guide cloth 6 in the left-right direction in this way, the guide cloth 6 can be smoothly expanded when the airbag 5 is expanded and deployed.

Further, the guide cloth 6 is made of, for example, the same base cloth as the base cloth constituting the airbag 5. The airbag base cloth is a durable base cloth that can withstand high-temperature and high-pressure expansion gas, and the cost can be reduced by diverting the airbag base cloth.

In addition, the base fabric for airbags is often surface-treated such as silicon coating on one side. Since the surface-processed surface has a higher frictional force than the non-coated surface, the guide cloth 6 is arranged so that the surface-processed surface contacts the surface of the hood 2 when the airbag 5 expands and expands. You may. Specifically, the guide cloth 6 is arranged so that the non-coated surface is arranged on the inside (airbag 5 side) and the surface-processed surface is on the outside in the state shown in FIG.

Further, as shown in FIG. 1, the vertical width of the guide cloth 6 (the length of the side arranged in the front-rear direction) covers at least the rear end portion of the hood 2 and its edge portion when the airbag 5 is expanded and deployed. Designed to a length that can be. Further, it is preferable that the vertical width of the guide cloth 6 is designed to have a length that can be sandwiched between the surfaces of the hood 2 by the expanded and expanded airbag 5 when the airbag 5 is expanded and expanded. For example, the lap length between the guide cloth 6 and the surface of the hood 2 is preferably about 30 mm or more.

Further, as shown in FIG. 2, the guide cloth 6 is arranged so as to cover the airbag 5 folded from the hood 2 side from the fixed end fixed to the fastener 14. The unfixed free end 61 of the guide cloth 6 may be inserted into the gap of the folded portion of the airbag 5, for example, as shown in FIG.

Further, when arranging the wrapping cloth that holds the folded shape of the airbag 5 from above the guide cloth 6, the free end 61 of the guide cloth 6 does not have to be inserted into the gap of the folded portion of the airbag 5.

Here, the expansion / deployment behavior of the airbag 5 will be described. When the vehicle collides with a pedestrian or the like, a signal is transmitted from the ECU (electronic control unit) mounted on the vehicle to the inflator 11, and the expansion gas is supplied from the inflator 11 into the airbag 5.

When the expansion gas is supplied to the airbag 5, as shown in FIG. 3, the airbag 5 cleaves the flat plate portion 13a of the airbag cover 13 from the tear line 13c, and the flat plate portion 13a faces the windshield 3 side. Rotate. The airbag 5 in which the flat plate portion 13a is cleaved is discharged to the outside of the vehicle.

At this time, since the lower end of the guide cloth 6 is fixed to the fastener 14, the free end 61 side of the guide cloth 6 is pushed out by the airbag 5 when the airbag 5 is expanded and deployed, as shown in FIG. , Will be located between the hood 2 and the airbag 5.

Further, when the expansion gas is supplied to the airbag 5, the airbag 5 expands and expands on the hood 2 and the windshield 3 as shown in FIG. At this time, the guide cloth 6 released to the surface of the hood 2 is pressed against the surface of the hood 2 as the expansion and deployment of the airbag 5 progresses, and a constant tension is generated between the fixed end and the free end 61.

Due to the tension of the guide cloth 6, the airbag 5 can be supported while the gap G formed between the airbag cover 13 and the hood 2 is sealed by the guide cloth 6. Therefore, according to the pedestrian protection airbag device 1 according to the present embodiment, it is possible to suppress the airbag 5 from slipping into the lower surface of the hood 2, and it is possible to stabilize the expanded and deployed shape of the airbag 5.

Here, FIG. 5 is a cross-sectional view showing a comparative example of the pedestrian protection airbag device. A comparative example shown in FIG. 5 is a pedestrian protection airbag device 1'not provided with a guide cloth 6. Further, FIG. 5 illustrates a state in which the expansion and deployment of the airbag 5'has been completed, similarly to the pedestrian protection airbag device 1 according to the present embodiment shown in FIG.

In the airbag 5'without the guide cloth 6, the side plate portion 13b'tends to be deformed outward because the airbag cover 13'starts to expand and expand at the time of expansion and deployment. Since the conventional pedestrian protection airbag device 1'does not have the guide cloth 6, the airbag 5'sinks into the lower surface of the hood 2'in response to the deformation of the side plate portion 13b'. First, the expansion and deployment shape of the airbag 5'becomes unstable due to the subduction of the airbag 5'.

In addition, as the expansion and deployment of the airbag 5'progresses, the airbag 5'may be deformed so as to roll up the rear end of the hood 2'. This deformation of the hood 2'also causes the airbag 5'to rise from the surface of the hood 2', and the expansion and deployment shape of the airbag 5'becomes unstable.

On the other hand, since the pedestrian protection airbag device 1 according to the present embodiment described above includes the guide cloth 6, it is constant between the fixed end and the free end 61 as shown in FIG. Tension can be generated. Therefore, the guided cloth 6 can support the expanded and deployed airbag 5, and the outward inclination of the side plate portion 13b of the airbag cover 13 can be suppressed.

As a result, in the pedestrian protection airbag device 1 according to the present embodiment, it is possible to suppress the slipping of the airbag 5 into the lower surface of the hood 2, and it is also possible to suppress the deformation of the rear end of the hood 2.

Next, a modified example of the pedestrian protection airbag device 1 according to the present embodiment will be described with reference to FIG. Here, FIG. 6 is a cross-sectional view showing a modified example of the pedestrian protection airbag device shown in FIG. 1, in which (A) is a first modified example and (B) is a second modified example. In each figure, the figures of the hood 2, the windshield 3 and the cowl 7 are omitted for convenience of explanation.

In the first modification shown in FIG. 6A, the free end 61 side of the guide cloth 6 is folded back on the rear side (windshield 3 side) and folded on the front side (hood 2 side). When the vertical width of the guide cloth 6 is long, the free end 61 side of the guide cloth 6 may be folded and arranged as shown in the figure. Although the case where the free end 61 side of the guide cloth 6 is folded in a single layer is shown here, it may be folded in double or triple.

In the second modification shown in FIG. 6B, the guide cloth 6 is composed of a part of the wrapping cloth that holds the folded shape of the airbag 5. In such a second modification, both ends of the guide cloth 6 are fixed to the fastener 14, and the planned fracture portion 62 is formed in the lower portion on the windshield 3 side.

Since the guide cloth 6 needs to have a certain vertical width, when the guide cloth 6 is broken at the planned break portion 62, the guide cloth 6 is broken so that the vertical width on the hood 2 side is sufficiently longer than that on the windshield 3 side. The position of the planned portion 62 is set.

It goes without saying that the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the spirit of the present invention.

1 Pedestrian protection airbag device 2 Hood 3 Windshield 4 Front pillar 5 Airbag 6 Guide cloth 7 Cowl 11 Inflator 12 Retainer 13 Airbag cover 13a Flat plate 13b Side plate 13c Tearline 13d Bending 14 Fastener 51 Central expansion 52 Overhanging expansion part 61 Free end 62 Expected breakage part

Claims (4)

In a pedestrian protection airbag device equipped with an airbag that is discharged from between the hood and the windshield located in front of the vehicle to cover the front pillars.
A guide cloth is provided between the hood and the expanded and deployed airbag when the airbag is expanded and deployed.
The guide cloth is composed of a part of a wrapping cloth that holds the folded shape of the airbag, and a fractured portion is formed in a lower portion on the windshield side.
A pedestrian protection airbag device that features. The first aspect of the present invention, wherein the airbag cover covers the airbag before expansion and deployment, and the airbag cover is configured to open toward the windshield side when the airbag is expanded and deployed. Pedestrian protection airbag device. The pedestrian protection air according to claim 2, wherein the airbag cover is configured to expand and deploy the airbag in a substantially vertical direction at an initial stage of expansion and deployment of the airbag. Bag device. The pedestrian protection airbag device according to claim 3, wherein the width of the guide cloth is smaller than the width of the airbag cover.

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