JP2008143301A - Hood airbag device for protecting pedestrian - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a hood airbag for protecting a pedestrian capable of suppressing the fall of the pedestrian run upon a front hood onto a road surface while the thickness of the airbag is substantially same between a side part and a center part. <P>SOLUTION: The hood airbag for protecting the pedestrian comprises an airbag body 10 having a plurality of cells 11 divided by a division line extending in the longitudinal direction of a vehicle in a deployed and inflated state, a sheet 20 which has the length in the vehicle width direction shorter than the length in the vehicle width direction of the airbag body 10 in the deployed and inflated state, and is stretched between both ends of the airbag body in the vehicle width direction on the upper side of the airbag body while the deployed and inflated shape of the airbag body has an upwardly recessed arch shape in the vehicle width direction. Since the sheet 20 makes the airbag body 10 in an upwardly recessed arch shape, any fall of a pedestrian run upon the hood airbag 1 onto a road surface from a front hood in the vehicle right-to-left direction can be suppressed or prevented. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a pedestrian protection hood airbag device that expands and inflates on a hood panel of a vehicle body at the time of a collision with a pedestrian, and a pedestrian riding on the hood airbag falls from the hood airbag in the vehicle width direction. The present invention relates to a hood airbag device for protecting pedestrians.

When a traveling vehicle collides with a pedestrian, the collided pedestrian is swung up by the front part of the vehicle body with the lower limbs and jumped up onto the front hood of the vehicle body, and may receive a collision impact from the front hood, There is a risk of falling further from the front hood onto the road surface. To mitigate and suppress these impacts, when a collision with a pedestrian is detected, it expands and expands on the front hood to mitigate the impact on the pedestrian, and has a bank on the side that is higher than the center. A hood airbag device has been proposed that prevents a pedestrian from falling on the road surface.
For example, Patent Document 1 discloses a fall-preventing hood airbag device provided with a saddle-shaped airbag whose height on all sides is higher than that of a central portion when deployed on a hood.
Patent Document 2 discloses a hood airbag device including a front cover part and left and right fall prevention parts.
Japanese Patent No. 3005627 (Japanese Patent Laid-Open No. 7-156749) JP 2004-136814 A

  In the conventional hood airbag device of Patent Literatures 1 and 2, after the airbag is inflated, the shape of the airbag having at least a part of the side portion that is thicker than the center portion, to the road surface of the pedestrian who rides on the front hood Therefore, there is a problem in that the structure of the airbag is complicated, resulting in an increase in manufacturing cost and a large space necessary for storing the airbag under the front hood.

  The object of the present invention is that the airbag thickness at the sides at both ends in the vehicle width direction (the thickness of the airbag body) and the airbag thickness at the center of the middle portion in the vehicle width direction (the thickness of the airbag body) are substantially the same. However, it is providing the hood airbag apparatus for pedestrian protection which can suppress the fall to the road surface of the pedestrian who got on the front hood.

The hood airbag device for pedestrian protection of the present invention which solves the above-mentioned subject and achieves the above-mentioned object,
A hood airbag device for protecting a pedestrian that expands and expands on a hood panel of a vehicle body at the time of a collision with a pedestrian,
An airbag body having a plurality of cells divided by a dividing line extending in the vehicle longitudinal direction in the deployed and inflated state;
The airbag body has a vehicle width direction length that is shorter than the vehicle width direction length of the airbag body in the deployed and inflated state, and is stretched between both ends of the airbag body in the vehicle width direction on the upper side of the airbag body. A seat having a concave arch shape upward in the vehicle width direction,
Have

  The cross-sectional shapes of the plurality of cells in the expanded and expanded state cut along the vertical plane extending in the vehicle width direction are substantially the same over all the cells. Accordingly, in the deployed and inflated state, the thickness of the cell of the airbag main body is substantially the same from the vehicle width direction center to the vehicle width direction both ends.

  In the hood airbag device for pedestrian protection, in the deployed and inflated state, all the cells communicate with a common passage extending in the vehicle width direction at the rear end in the vehicle front-rear direction, and the inflation gas of the inflator is passed through the passage. As a result, all cells expand and expand almost simultaneously.

  Normally, the pedestrian protection hood airbag device is stored in the airbag storage space provided below the rear end of the vehicle front-rear direction of the hood airbag or in the cowl portion, and provided at the front end of the vehicle. When a sensor that detects a collision with a pedestrian detects a collision with a pedestrian or when a collision with a pedestrian is predicted, the inflator is detonated and the hood airbag device for protecting the pedestrian is placed on the upper surface of the front hood. Deploy and inflate almost the entire area of the front hood.

  According to the pedestrian protection hood airbag device of the present invention, since the airbag body has a plurality of cells, the pedestrian protection hood airbag device is deployed and inflated on the hood panel of the vehicle body at the time of collision with the pedestrian. When this is done, the cell thickness of the side and center airbags is approximately the same. As a result, the structure of the airbag main body is simplified, the manufacturing cost is reduced, and the storage space is reduced as compared with the conventional structure in which the inflation height of the side portion is higher than the inflation height of the central portion. In addition, the cell shape ensures that the cell thickness in the entire area of the airbag body is almost constant, and when the pedestrian is lifted up on the airbag body, the front hood is attached to the bottom and the front hood is deformed. The bottoming of the solid under the front hood can be suppressed. Further, the cell body enables the airbag body to be deformed into an arch shape by the seat.

  Further, since the seat has a vehicle width direction length that is shorter than the vehicle width direction length of the airbag body and is stretched between both ends of the airbag body in the vehicle width direction on the upper side of the airbag body, the seat is the airbag body. The expanded and inflated shape can be formed into a concave arch shape upward in the vehicle width direction. As a result, it is possible to suppress or prevent a pedestrian who once rides on the hood airbag from falling from the front hood to the road surface in the vehicle left-right direction.

  In addition, even if the pedestrian's riding position is shifted from the vehicle lateral center point of the hood airbag in the vehicle lateral direction, it is moved toward the vehicle lateral center point by the arch shape of the deployment airbag body, A pedestrian riding on the airbag is prevented from colliding with a highly rigid A pillar (front pillar) located at the rear end of the vehicle and in the lateral direction of the vehicle.

A pedestrian protection hood airbag device (hereinafter referred to as a pedestrian protection hood airbag device of the present invention) according to the best mode for carrying out the present invention will be described with reference to FIGS. However, in FIGS. 1 to 3, the passage 13 and the inflator 30 described later are not shown. The passage 13 and the inflator 30 are shown in FIG.
A pedestrian protection hood airbag device (hereinafter simply referred to as a hood airbag device) 1 according to the present invention is a hood airbag device that is deployed and inflated on a hood panel 3 of a vehicle body 2 at the time of a collision with a pedestrian A.

  The hood airbag device 1 includes an airbag body 10 and a seat 20. The airbag main body 10 of the hood airbag apparatus 1 is connected to the inflator 30, and the inflation gas of the inflator 30 is supplied to the airbag main body 10 at the time of a collision with the pedestrian A. It expands and expands on the (front) hood panel 3.

  Normally, the hood airbag device 1 is stored in an airbag storage space provided below the rear end of the hood panel 3 in the vehicle front-rear direction or in a cowl portion. In the stored state, the casing is folded and stored, and the casing is fixed to the vehicle body. A sensor 4 (for example, disclosed in JP-A-8-183422 or JP-A-2006-281989) provided on a front end of a vehicle (for example, a front bumper) for detecting a collision with a pedestrian is disclosed. When a collision with the pedestrian A is detected or when a collision with the pedestrian A is predicted, the inflator 30 is detonated and the hood airbag device 1 is moved in the vehicle longitudinal direction of the hood panel 3. The door provided at the rear end is opened or expanded through the cowl gap on the upper surface of the hood panel 3 and over almost the entire area of the hood panel 3.

  The airbag body 10 has a substantially rectangular quadrilateral shape including two sides 10a and 10b extending in the vehicle longitudinal direction and two sides 10c and 10d extending in the vehicle width direction. The length of the airbag body 10 in the vehicle longitudinal direction is substantially equal to the length of the hood panel 3 in the vehicle longitudinal direction, and the length of the airbag body 10 in the vehicle width direction is substantially equal to the length of the hood panel 3 in the vehicle width direction.

The airbag body 10 is made of, for example, a cloth (including a cloth inner surface coated with a resin coating) or a resin, and is formed by stitching a bag upper cloth 14 and a bag lower cloth 15 together.
The airbag main body 10 includes a plurality of cells divided by a dividing line 12 extending in the vehicle front-rear direction in the deployed and inflated state of the airbag main body 10 (here, the cells are the surroundings except for a communication portion to a passage 13 described later). 11) (referred to as a closed chamber). In the deployed and inflated state of the airbag body 10, the plurality of cells 11 extend in the vehicle front-rear direction, and the dividing line 12 delimits adjacent cells 11. The dividing line 12 may be a suture line. Reference numeral 16 denotes a suture line that is not the dividing line 12. The suture line 16 that is not the dividing line 12 includes a suture line around the periphery of the bag upper cloth 14 and the bag lower cloth 15. One of the bag upper cloth 14 and the bag lower cloth 15 is fixed to the other at a parting line 12 portion composed of a suture line, and one of the bag upper cloth 14 and the bag lower cloth 15 is loosened with respect to the other at a part between adjacent parting lines. By holding it, the cell 12 can be expanded by reliably supplying the expansion gas to the cell 12.

  When the hood airbag device 1 is deployed and inflated, all the cells 11 communicate with a common passage 13 extending in the vehicle width direction at an end of the cell 11 in the vehicle front-rear direction, and an inflator 30 is connected to the passage 13. The expansion gas is ejected, and all the cells 11 are expanded and expanded almost simultaneously. The inflator 30 may be installed in the passage 13 or may be provided outside the airbag body 10 and communicated with the passage 13 by piping.

  The cross-sectional shapes of the plurality of cells 11 in the deployed and inflated state of the airbag body 10 cut along the vertical plane extending in the vehicle width direction are substantially the same for all the cells 11, for example, substantially semi-elliptical or semi-circular Etc. Note that the cross-sectional shape of the cell 11 may be elliptical, circular, or the like. Therefore, in the deployed and inflated state of the airbag main body 10, the thickness of the cell 11 of the airbag main body 10 (thickness in the direction orthogonal to the top surface of the cell) is Is almost the same (almost constant).

  The seat 20 has a substantially rectangular quadrilateral shape including two sides 20a and 20b extending in the vehicle front-rear direction and two sides 20c and 20d extending in the vehicle width direction. The seat 20 has a vehicle width direction length W1 shorter than the length W1 of the airbag body 10 in the deployed and inflated state (the length of the curved surface along the arch when the airbag body 10 takes the arch shape). W2. The seat 20 is connected to two sides 10a and 10b of the airbag body 10 extending in the vehicle front-rear direction by two sides 20a and 20b extending in the vehicle front-rear direction. When the airbag body 10 is deployed and inflated, the seat 20 is stretched between both ends of the airbag body 10 in the vehicle width direction on the upper side of the airbag body 10, and the airbag body 10 is deployed and inflated (the airbag body 10 in the longitudinal direction of the vehicle). Is a arch shape that is concave upward in the vehicle width direction. Even in the state where the airbag main body 10 is in an arch shape, the airbag main body 10 covers almost the entire area of the hood panel 3 from above.

  As shown in FIG. 1, there is a gap in the vertical direction between the airbag main body 10 and the seat 20 that have an arch shape, except for both ends of the seat 20 in the vehicle width direction. As shown in FIG. 2, when the pedestrian A colliding with the seat 20 rides, the weight of the colliding pedestrian A is applied to the seat 20 and the portion of the seat 20 on which the pedestrian weight is applied is displaced downward. . As a result, the seat 20 is deformed (in a “V” shape) and the vehicle width direction interval between both ends of the seat 20 in the vehicle width direction is narrowed. Pull to the center in the width direction. As a result, the depth of the arch shape of the airbag body 10 (the vertical distance between the line connecting both ends of the arch and the lowest point of the recess of the arch) becomes deeper, and the arch shape of the airbag body 10 in the vehicle width direction The height from the hood panel 3 at both ends is higher than in the state of FIG.

Next, functions and effects of the hood airbag device 1 of the present invention will be described.
The sensor 4 detects a collision with the pedestrian A, the inflator 30 is activated, and the airbag body 10 is deployed and inflated on the hood panel 3.
As the airbag body 10 is deployed and inflated, the seat 20 extending between both end portions in the vehicle width direction of the airbag body 10 is stretched, and the deployed shape of the airbag body 10 is a concave arch shape (arc shape) upward. Become. This state is completed before the pedestrian A falls on the seat 20. This state is shown in FIG.

  When the pedestrian A is struck by the vehicle bumper and the upper body falls over the seat 20, the pedestrian A rides on the hood airbag device 1 while pressing the seat 20. This state is shown in FIG. At this time, the pedestrian A riding part of the seat 20 is displaced downward, hits the airbag body 10, and the impact to the pedestrian A is absorbed by the deformation of the cell 11 of the airbag body 10. Since the airbag body 10 is divided into the cells 11, among the cells 11 of the airbag body 10, the cells 11 on which the load of the pedestrian is applied are such that the bag upper cloth 14 is attached to the bag lower cloth 15. The air cushion of the cell 11 protects the pedestrian A from the impact caused by the collision with the hood panel 3.

  When the pedestrian A falls on the seat 20 and presses down on the seat 20, both end portions in the vehicle width direction of the airbag body 10 are lifted upward while being attracted to the vehicle width direction center side. As a result, both ends of the airbag body 10 in the vehicle width direction are lifted on both sides in the vehicle width direction of the rider pedestrian A, and walls higher than the center in the vehicle width direction are formed. This wall suppresses or prevents the pedestrian A from falling on the road surface in the vehicle width direction from the hood panel 3, and prevents the pedestrian A from falling on the road surface and receiving an impact or being caught in the rear wheel. Or prevent.

  Further, in the hood airbag device 1 in which the airbag main body 10 is deployed in an arch shape (arc shape), the riding position of the pedestrian A on the hood airbag device 1 is the central portion of the hood airbag device 1 in the vehicle width direction. Even if the vehicle is displaced in the vehicle width direction, after riding on the hood airbag device 1, the pedestrian A moves and guides to the center in the vehicle width direction, and the pedestrian A moves over the hood airbag device 1. Even when the vehicle moves backward with respect to the vehicle, the collision with the highly rigid A pillar (front pillar) 5 is suppressed or prevented.

It is a perspective view at the time of deployment of the hood airbag device for pedestrian protection of the present invention on the food panel of vehicles. It is a perspective view at the time of pedestrian riding of the hood airbag device for pedestrian protection of FIG. FIG. 2 is a cross-sectional view of the pedestrian protection hood airbag device of FIG. 1 as viewed in the vehicle front-rear direction by cutting the cell part along a vertical plane orthogonal to the vehicle front-rear direction. It is a top view of the airbag main body in the state which made the airbag main body of the food airbag apparatus for pedestrian protection of FIG. 1 flat.

Explanation of symbols

1 Hood airbag device for pedestrian protection (hood airbag device)
2 Body (vehicle)
3 (Front) Hood panel 4 Sensor 5 A pillar (Front pillar)
DESCRIPTION OF SYMBOLS 10 Airbag main body 10a, 10b Two sides 10c extended in a vehicle front-back direction 10d Two sides extended in a vehicle width direction 11 Cell 12 Dividing line (The case where it is a suture line is included)
13 Passage 14 Bag upper cloth 15 Bag lower cloth 16 Stitch line 20 Seats 20a, 20b Two sides 20c, 20d extending in the vehicle front-rear direction Two sides 30 extending in the vehicle width direction Inflator A Pedestrian W1 Vehicle of airbag body in deployed and inflated state Width in the width direction W2 Length in the vehicle width direction of the seat

Claims (1)

A hood airbag device for protecting a pedestrian that is supplied with inflation gas from an inflator at the time of a collision with a pedestrian and expands and expands on a hood panel of a vehicle body,
An airbag body having a plurality of cells divided by a dividing line extending in the vehicle longitudinal direction in the deployed and inflated state;
The airbag body has a vehicle width direction length that is shorter than the vehicle width direction length of the airbag body in the deployed and inflated state, and is stretched between both ends of the airbag body in the vehicle width direction on the upper side of the airbag body. A seat having a concave arch shape upward in the vehicle width direction,
A hood airbag device for protecting pedestrians.

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