JP2008254492A - Pedestrian protection device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a pedestrian protection device capable of attaining miniaturization of an air bag without excessively impairing impact absorption ability relative to a pedestrian. <P>SOLUTION: A front side inflation part 11a inflated/deployed so as to cover an upper part of a vehicle front side of a front fender 2 and a rear side inflation part 11c inflated/deployed so as to cover an upper part at a vehicle rear side of the front fender 2 are provided. Thickness of the front side inflation part 11a is set smaller than thickness of a rear side inflation part 11c. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a pedestrian protection device capable of protecting a pedestrian while suppressing damage received from the vehicle as much as possible when the pedestrian interferes with the vehicle.

Conventionally, a device described in Patent Document 1 has been proposed as a device for the purpose of protecting pedestrians. That is, the airbag is folded and stored in the vicinity of the front fender located on both sides of the hood panel in the vehicle width direction. When a pedestrian interferes with the front part of the vehicle, an inflation gas flows into the airbag. And expand. Therefore, the inflated and deployed airbag suppresses direct contact between a pedestrian and a hard member such as a hood ridge rein hose positioned below the front fender.
Japanese Patent Laid-Open No. 2007-8278

  By the way, the arrangement space of the airbag and the inflator which becomes the generation source of the gas for inflating the front fender is limited. On the other hand, such an airbag tends to increase in size as it tries to improve the performance of absorbing pedestrian impact, and the impact reduction performance of the airbag in a limited installation space. Optimization for improvement was necessary.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide a pedestrian protection device that can reduce the size of an airbag without excessively impairing the ability to absorb shocks to a pedestrian. is there.

  In order to solve the above-mentioned problem, the invention according to claim 1 is a pedestrian protection device that suppresses interference between a front fender of a vehicle and a pedestrian so as to cover an upper portion of the front fender on the front side of the vehicle. A front-side inflating portion that inflates and deploys, and a rear-side inflating portion that inflates and deploys so as to cover an upper portion of the front fender on the vehicle rear side, and the front-side inflating portion has an impact greater than that of the rear-side inflating portion The gist is that the reduction performance is set low.

  When a pedestrian interferes with the front fender, the contact position of the head particularly differs depending on the pedestrian's physique. For example, in the case of a small person such as a child, the contact position is biased toward the front side of the front fender, while in the case of an adult with a normal physique, the contact position is biased toward the rear side of the front fender. . And in the case of a person with a small physique, even if the impact reduction performance of the inflating part that is in contact is low compared to the case of a normal person with a physique, the load acting on the inflating part is small, so there is a problem in its protective performance It is unlikely to occur. Therefore, as in the above configuration, by setting the impact reduction performance of the rear side expansion portion arranged on the vehicle rear side of the front fender with high possibility of contact with a normal physique higher than that of the front side expansion portion, In addition, it is possible to appropriately set the distribution of the impact reduction performance in the entire inflating portion. Therefore, compared with a conventional airbag having a uniform overall impact reduction performance, the front side inflatable portion and the configuration required for the inflation can be reduced in size, and the device without excessively impairing the impact reduction performance for pedestrians. The overall size can be reduced.

  The impact reduction performance referred to here is, for example, the internal pressure of the inflating portion filled with the inflating gas as described in claim 2, or the inflating portion covering the front fender as in claim 3. It is prescribed by the thickness. That is, when the internal pressure of the inflating part is high, it is suppressed from being dented by the load received when the inflating part comes into contact with the pedestrian, so that the front fender and the pedestrian are prevented from interfering when the inflating part is indented. Thus, the impact on the pedestrian is reduced. If the internal pressure of the inflating part is set too high when the load acting on the inflating part is small like a person with a small physique, the impact may not be reduced appropriately. Also, if the thickness of the inflatable part that covers the front fender is large, the distance from the outer surface of the inflatable part to the front fender is large, so that the pedestrian and the front fender will interfere with this inflating part. Cost. For this reason, the front fender and the pedestrian are prevented from interfering with each other when the inflating portion is recessed, and the impact on the pedestrian is reduced.

From the above, the gist of the invention described in claim 2 is that the internal pressure of the front side expansion part is set lower than the internal pressure of the rear side expansion part.
In this case, since the internal pressure of the front side expansion portion can be reduced, the amount of gas for expansion can be reduced, and as a result, the inflator serving as the generation source can be downsized. Moreover, since it can suppress that the internal pressure of an expansion | swelling part is set too high with respect to a person with small physique, an impact can be reduced appropriately according to a pedestrian's physique.

In the invention according to claim 3, the gist is that the thickness of the front expansion part is set smaller than the thickness of the rear expansion part.
In this case, since the volume of the front side expansion portion is reduced, the entire apparatus can be reduced in size.

  Invention of Claim 4 is a pedestrian protection apparatus as described in any one of Claims 1-3. As the said front side expansion | swelling part and the said back side expansion | swelling part go to the back side from a vehicle front side, it is. The gist is that the impact reduction performance is set to gradually increase.

  Since the required impact reduction performance differs depending on the pedestrian's physique as described above, the optimal configuration of the pedestrian protection device is to increase the impact reduction performance as the pedestrian with a large physique interferes. Is desirable. Therefore, as described in claim 4, if the front side inflating portion and the rear side inflating portion are set so that the impact reduction performance is gradually increased from the vehicle front side to the rear side, the physique of the pedestrian is increased. It is possible to achieve impact reduction performance according to the above.

  Invention of Claim 5 is a pedestrian protection apparatus as described in any one of Claims 1-4. WHEREIN: The said front side expansion part is filled with gas earlier than the said back side expansion part. Is the gist.

  When the front part of the vehicle and the pedestrian come into contact with each other, the smaller the physique, the shorter the distance from the head to the front fender. Therefore, in order to appropriately protect such a person with a small physique, by allowing gas to flow in from the inflatable portion on the front side, the inflatable portion can be inflated and deployed at an early stage to protect the pedestrian. Become.

  The gist of the invention according to claim 6 is the pedestrian protection device according to any one of claims 1 to 5, further comprising a pillar inflating portion that inflates in a manner covering the front pillar of the vehicle. .

  According to this configuration, the pedestrian can be prevented from interfering with the front pillar, and the pedestrian can be further protected.

  According to the pedestrian protection device of the present invention, it is possible to reduce the size of the airbag without excessively impairing the ability to absorb shock to the pedestrian.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings. In this specification, the front and rear and up and down directions are based on the direction along the front and rear and up and down directions of the vehicle, and the left and right directions are directions along the left and right directions when the rear side is viewed from the front side of the vehicle. Based on

  As shown in FIG. 1, the pedestrian protection apparatus according to the present embodiment includes two airbag devices disposed at the front fender 2 portions located on the left and right edges of the hood panel 1 disposed on the front end side of the vehicle. 10L and 10R.

  As shown in FIG. 2, a hood ridge rein hose 4, which is a member on the body 3 side, is disposed in the front fender 2 along the front-rear direction and covers the top of the hood ridge rein hose 4. Thus, the front fender panel 5 is disposed. Further, as shown in FIG. 2, the front fender panel 5 is arranged so that the surface thereof is substantially flush with the surrounding hood panel 6. In the case of the embodiment, the hood panel 6 includes an outer panel 7 and an inner panel 8 that are both made of sheet metal. In the case of the embodiment, the hood panel 6 is made of aluminum (made of aluminum alloy).

  The airbag devices 10L and 10R are composed of the same members that are symmetrical. In the embodiment, an airbag device 10R disposed on the right side will be described as an example. As shown in FIG. 2, the airbag device 10R includes an airbag 11, an inflator 12 that supplies inflation gas to the airbag 11, a storage unit 13 that stores the folded airbag 11 and the inflator 12, and An airbag cover 14 that covers the upper side of the storage portion 13 is provided.

  As shown in FIG. 2, the storage portion 13 is disposed along the front-rear direction at the front fender 2, and is recessed so that the front fender panel 5 protrudes downward. It is integrally formed. Specifically, the storage portion 13 is configured by recessing the front fender panel 5 in a substantially boxed shape with a bottom having an open upper side, and is formed in a substantially rectangular tube shape disposed along a substantially vertical direction. The peripheral wall part 15 and the bottom wall part 16 disposed so as to close the lower end side of the peripheral wall part 15 are provided.

  The airbag cover 14 is made of a synthetic resin such as an olefin-based thermoplastic elastomer, and is disposed on the upper side of the storage portion 13 so as to cover the opening 13 a of the storage portion 13. The airbag cover 14 includes a door portion 14a that can be opened when the airbag 11 protrudes. Specifically, at the peripheral edge of the door portion 14a, a to-be-breakable portion 14b having a substantially U-shape in plan view that can be broken when the airbag 11 protrudes, and a hinge portion 14c serving as a rotation center when opened. Are arranged, and the door portion 14a can be opened by breaking the breakable portion 14b.

  As shown in FIG. 1, the inflator 12 is disposed on the front end side of the storage portion 13 and has a substantially cylindrical shape having a gas discharge port (not shown). The inflator 12 is connected to a portion of the airbag 11 on the vehicle front side so that inflation gas can flow into the airbag 11. As shown in FIG. 2, each inflator 12 is held by a sheet metal bracket 18, and the bracket 18 is fastened and fixed to the storage portion 13.

  The airbag 11 is inflated by inflating the gas for inflation discharged from the inflator 12, and in the case of the embodiment, the airbag 11 has a bag shape formed from a woven fabric using polyester or polyamide yarn, As shown in FIG. 2, the inflator 12 and the storage unit 13 are fixed together. In addition, the airbag 11 is subjected to surface processing in order to block minute holes existing on the surface thereof and prevent the escape of gas. This is to maintain the internal pressure of the airbag 11 during this time because it may take time from the inflow of gas to the airbag 11 to contact with the pedestrian. Further, as shown in FIG. 3, the airbag 11 is formed in a substantially rectangular sheet shape with the longitudinal direction extending in the front-rear direction when the inflation is completed, and the hood panel 6 is disposed above the front fender 2 when the inflation is completed. Including the upper side on the edge side in the left-right direction, and inflating and deploying so as to cover substantially the entire region. A more detailed structure of the airbag 11 will be described with reference to FIG. 4 showing a cross-sectional structure of the airbag 11 during inflation and deployment.

  As shown in FIG. 4, the airbag 11 is partitioned into a plurality of inflating portions along the vehicle longitudinal direction. In the case of the embodiment, the airbag 11 is partitioned into three inflating portions along the vehicle front-rear direction, and these are respectively referred to as a front inflating portion 11a, a central inflating portion 11b, and a rear inflating portion 11c from the front side. . This front-side inflatable part 11a is a part where the head is likely to interfere particularly when a small physique like a child comes into contact with the front of the vehicle, while the rear-side inflatable part 11c is usually a physique. This is a part where the head of the person is likely to interfere particularly when contacting the front of the vehicle. The thicknesses L1, L2, and L3, which are the thicknesses of the inflated portions of the inflatable portions 11a to 11c, are set such that the thickness L1 <thickness L2 <thickness L3. And if the thickness at the time of inflating and deploying becomes large in this way, the distance from the outer surface of these inflating parts to the front fender 2 is large. It needs to be dented. Therefore, the front fender 2 and the pedestrian are prevented from interfering with each other when the inflating portion is recessed, and the impact on the pedestrian is reduced. Therefore, in the airbag 11, the volume of the inflatable portion closer to the vehicle rear side is larger so that a larger load of a pedestrian can be received, while the volume of the inflatable portion closer to the vehicle front side is smaller. Yes. Further, a pillar inflating portion 11d is extended from the rear inflating portion 11c of the airbag 11 toward the obliquely upper side. The pillar inflating portion 11d is configured to cover the front pillar 17 of the vehicle when the airbag 11 is inflated and deployed.

  Further, as shown in FIG. 6, a sensor 20 capable of detecting a collision with a pedestrian is disposed on the front bumper 19. An airbag operation circuit (not shown) is configured to operate the inflator 12 to deploy and inflate the airbag 11 when a signal that detects a collision with a pedestrian is input from the sensor 20.

  In the pedestrian protection device according to the embodiment, when the vehicle is mounted, the sensor 20 disposed in the front bumper 19 detects a collision with the pedestrian, and an operation signal is input to each inflator 12 of the airbag devices 10L and 10R. The Next, the inflation gas is discharged from the inflator 12, and the airbag 11 is inflated by the inflow of the inflation gas. When the door portion 14a of the airbag cover 14 is pressed against the airbag 11, the planned fracture portion 14b is broken and opened, and the airbag 11 protrudes upward from the storage portion 13 from the opened portion. As shown in FIG. 5 and FIG. 6, the expansion is completed. At this time, the inflating gas from the inflator 12 flows in from the front side inflating part 11a of the airbag 11, so that the inflating of this part is completed earliest, and the gas filled in this front side inflating part 11a is next. It flows into the central expansion part 11b and the rear side expansion part 11c.

  And when the pedestrian who contacted the vehicle is a person with a small physique like a child, for example, the head tends to go to the position where the front side inflating part 11a is inflated and deployed. However, since the inflating and unfolding of the front side inflating part 11a is completed at an early stage as described above, the front side inflating part 11a close to the position of the pedestrian at the time of the collision can appropriately receive the pedestrian. become. Moreover, since the thickness L1 of the front expansion part 11a is smaller than the thicknesses L2 and L3 of the other expansion parts, the impact reduction performance is low. However, since the load acting from a pedestrian with a small physique is small, the front side inflating part 11a is suppressed from being greatly recessed so that the pedestrian and the front fender 2 interfere with each other even with such a front side inflating part 11a. ing.

  Moreover, when the pedestrian who contacted the vehicle is a person with a normal physique, there is a high possibility that the head of the pedestrian is in contact with the rear-side inflating part 11c. In this case, although the load which acts on the back side expansion part 11c becomes large with a pedestrian's physique, since the thickness L3 is set larger than the other site | part in the back side expansion part 11c, a pedestrian And the front fender 2 are prevented from directly interfering with each other.

  Furthermore, depending on the collision mode between the vehicle and the pedestrian, the pedestrian may go toward the front pillar 17 of the vehicle, but in this case as well, the interference between the pedestrian and the front pillar 17 is suppressed by the pillar expansion portion 11d. Will come to be.

The pedestrian protection apparatus of the present embodiment described above can achieve the following effects.
(1) A front-side inflating portion 11a that inflates and deploys so as to cover the upper front side of the front fender 2 and a rear-side inflating portion 11c that inflates and deploys so as to cover the upper side of the front fender 2 on the rear side of the vehicle is provided. The rear side expansion part 11c is set to have a higher impact reduction performance than the front side expansion part 11a. Therefore, by setting the impact reduction performance of the rear side inflatable portion 11c arranged on the vehicle rear side of the front fender 2 that is likely to come into contact with a normal physique higher than that of the front side inflatable portion 11a, the airbag It is possible to appropriately set the distribution of impact reduction performance in the entire 11. Therefore, compared with a conventional airbag having a uniform overall impact reduction performance, the front-side inflatable portion 11a and the configuration required for the inflation can be downsized without excessively impairing the impact reduction performance for a pedestrian. The entire apparatus can be reduced in size.

  (2) The thickness L1 of the front expansion part 11a is set to be smaller than the thickness L3 of the rear expansion part 11c. In this case, since the volume of the front side expansion part 11a becomes small, the whole apparatus can be downsized.

  (3) The thickness of the airbag 11 increases as it goes from the vehicle front side to the rear side. Therefore, it can be set so that the impact reduction performance gradually increases as the airbag 11 is moved from the vehicle front side to the rear side, so that the impact reduction performance according to the pedestrian's physique can be realized. Become.

  (4) The gas is filled in the front side expansion portion 11a earlier than the rear side expansion portion 11c. When the front part of the vehicle and a pedestrian come into contact with each other, the smaller the physique, the shorter the distance from the head to the front fender 2, so the time until this interference is shorter. Therefore, in order to appropriately protect such a person with a small physique, by allowing gas to flow from the front side inflating portion 11a, the front side inflating portion 11a can be inflated and deployed at an early stage to protect the pedestrian. become able to.

  (5) The pillar inflating portion 11d that inflates in a manner covering the front pillar 17 of the vehicle is provided. Therefore, the pedestrian can be prevented from interfering with the front pillar 17, and the pedestrian can be further protected.

In addition, this embodiment can also be implemented with the following forms which changed this suitably.
In the above embodiment, the pillar inflating part 11d that inflates and deploys so as to cover the front pillar 17 is provided in the airbag 11, but this configuration can be omitted.

  In the above-described embodiment, the gas from the inflator 12 is caused to flow into the front side expansion portion 11a before the rear side expansion portion 11c, but the order of gas filling is not limited thereto. For example, if separate inflators are provided on the front side and the rear side of the front fender 2, and gas is discharged from each inflator to the front side expansion part 11a and the rear side expansion part 11c, the front side expansion part 11a can complete expansion and deployment at an early stage. It is also possible to adopt a configuration in which an inflating gas is first introduced into the central inflating part 11b and this gas is preferentially introduced into the front inflating part 11a.

  -The airbag 11 is configured by the front-side inflatable portion 11a and the rear-side inflatable portion 11c, and the configuration in which the thickness is gradually increased from the front-side inflatable portion 11a to the rear-side inflatable portion 11c is omitted. You can also. Moreover, in each of the front side expansion part 11a and the rear side expansion part 11c, you may set so that thickness may become large gradually as it goes to a rear side from the vehicle front side.

  -As a method of setting the impact reduction performance of the airbag 11, it can also be set by the internal pressure of the airbag 11, for example. In this case, if the front-side inflatable portion 11a is set to a low internal pressure compared to the rear-side inflatable portion 11c, the capacity of the gas required for the inflation of the airbag 11 as a whole is reduced, and the inflator 12 can be downsized. . Moreover, since it can suppress that the internal pressure of an expansion | swelling part is set too high with respect to a person with a small physique, an impact can be reduced appropriately according to a pedestrian's physique.

  In the above embodiment, the inside of one airbag 11 is partitioned to form the inflating portions 11a to 11d, but may be configured independently by separate airbags.

The top view which shows the front part of the vehicle by which the pedestrian protection apparatus concerning this invention is mounted from upper direction. Similarly, sectional drawing which shows the accommodation aspect of the airbag apparatus in a front fender. Similarly, the perspective view which shows the perspective state of the front part of the vehicle by which a pedestrian protection apparatus is mounted. Similarly, sectional drawing which shows the cross-sectional structure at the time of inflation deployment of an airbag. Similarly, sectional drawing which shows the state which the airbag of the airbag apparatus inflate-deployed in the front fender. Similarly, the side view which shows the state which the airbag of the airbag apparatus inflate-deployed in the front fender from the side.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 2 ... Front fender, 11 ... Air bag, 11a ... Front side expansion part, 11c ... Back side expansion part, 11d ... Pillar expansion part, 17 ... Front pillar.

Claims (6)

A pedestrian protection device that suppresses interference between a front fender of a vehicle and a pedestrian,
A front-side inflating portion that inflates and expands so as to cover an upper portion of the front fender on the vehicle front side;
A rear side inflating part that inflates and expands so as to cover the upper side of the front fender of the vehicle rear side,
The pedestrian protection device according to claim 1, wherein the front side inflating part is set to have a lower impact reduction performance than the rear side inflating part. In the pedestrian protection device according to claim 1,
The impact reduction performance is defined by the internal pressure of the expansion part filled with an expansion gas,
The internal pressure of the front side expansion part is set lower than the internal pressure of the rear side expansion part. In the pedestrian protection device according to claim 1,
The impact reduction performance is defined by the thickness of the inflatable portion covering the front fender,
The thickness of the said front side expansion | swelling part is set smaller than the thickness of the said back side expansion | swelling part. The pedestrian protection apparatus characterized by the above-mentioned. In the pedestrian protection device according to any one of claims 1 to 3,
The pedestrian protection device according to claim 1, wherein the front-side inflating portion and the rear-side inflating portion are set such that impact reduction performance is gradually increased from the vehicle front side to the rear side. In the pedestrian protection device according to any one of claims 1 to 4,
The pedestrian protection device according to claim 1, wherein the front side inflatable portion is filled with gas earlier than the rear side inflatable portion. In the pedestrian protection device according to any one of claims 1 to 5,
A pedestrian protection device comprising a pillar inflating portion that inflates in a manner covering the front pillar of the vehicle.

Images