JP2008162326A - Airbag system for rear end collision - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To rapidly fill gas in an airbag corresponding to the head of an occupant seated in a rear seat of a vehicle. <P>SOLUTION: This airbag is constituted so that an internal expansion portion 14 is formed so as to include a passage which allows gas to flow into from upward, a head expansion portion 20 expanding and deploying for the head of an occupant P seated in the rear seat 1 with the airbag 11 deployed. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention mainly fills an airbag in an upper part of a vehicle by filling a gas blown from an inflator serving as a gas generation source into an internal inflation portion formed inside an airbag accommodated in a ceiling of the vehicle. The present invention relates to a rear impact airbag device that is inflated and deployed downward from the rear.

  Various occupant protection devices have been proposed for vehicles in order to ensure safety in the event of a collision. As a representative example of such occupant protection devices, for example, an airbag device described in Patent Document 1 can be cited. . In this airbag device, the airbag is folded and stored in the ceiling of the vehicle. When a large impact such as a collision of another vehicle is applied to the vehicle, the airbag is filled with gas from the inflator. This is configured to inflate and deploy from the ceiling to the vehicle interior, that is, from above to below, at the rear of the vehicle.

More specifically, an internal inflating portion that is inflated when gas is filled in the air bag is formed, and an inflator that is formed at the center position in the vehicle width direction and serves as a gas generation source is formed in the internal inflating portion. Gas flows into the inside from the connected gas inlet. The inflowing gas flows in the interior inflating portion in the downward direction of the vehicle and is filled in a portion of the airbag on the vehicle lower side, and then is shunted from the portion to both sides of the vehicle, thereby sitting on the rear seat. Gas is filled into a portion corresponding to the head of the occupant.
JP 2006-96101 A

  By the way, in the rear impact airbag as described above, in order to catch the head of the occupant seated on the rear seat at the lower end portion thereof, the internal expansion portion of the lower end portion has an expansion capacity higher than this. It is set larger than the position where it is located. Since the gas is diverted from the center of the internal expansion portion of the lower end portion to both side portions of the vehicle, the gas filling to the portion corresponding to the head of the occupant seated on the rear seat has a relatively large expansion capacity. This is performed after passing through a large internal expansion portion, and the expansion timing tends to be delayed. Therefore, in order to be able to quickly receive the occupant's head, a quicker expansion of the portion corresponding to the head is desired, and there is still room for improvement in this respect.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide a rear-impact airbag device that can quickly fill a portion of an airbag corresponding to the head of an occupant seated on a rear seat of a vehicle with gas. It is to provide.

  In order to solve the above-described problem, the invention according to claim 1 is directed to a gas ejected from an inflator serving as a gas generation source with respect to an internal expansion portion formed inside an airbag accommodated in a ceiling of a vehicle. In the rear-impact airbag device in which the airbag is inflated and deployed from the upper side to the lower side of the vehicle by being filled, the internal inflation portion is a head of an occupant seated on a rear seat when the airbag is deployed It includes a passage through which the gas flows from above into the head inflating portion that inflates and expands correspondingly.

  According to this configuration, gas flows into the head inflating portion from above and gas does not pass through the inflating portion on the lower end side of the airbag having a relatively large expansion volume. It becomes possible to fill quickly. The head inflating portion that inflates and deploys corresponding to the head of an occupant seated on the rear seat is a portion of the internal inflating portion that faces, for example, a headrest provided on the rear seat in the vehicle front-rear direction.

  Further, the invention according to claim 2 is the rear impact airbag device according to claim 1, wherein the internal inflating portion is a gas inflow into which the gas from the inflator flows when the airbag is deployed. A horizontal passage that is connected to the vehicle and extends in the left-right direction of the vehicle, and a vertical passage that is connected to both ends of the horizontal passage and extends downward.

  According to this configuration, the lateral passage connected to the gas inflow portion is first filled with gas, and subsequently the expansion and deployment of the longitudinal passage is completed, so that the folding of the entire airbag is appropriately released and its shape Becomes stable, and the subsequent gas filling proceeds smoothly. Then, since the expansion of the head inflating portion is completed thereafter, the head inflating portion is smoothly filled even at an early stage, and the head expanding portion can be stably inflated and deployed. It becomes like this.

  Further, the invention according to claim 3 is the rear-impact airbag device according to claim 1 or 2, wherein the internal inflating portion is a pair of head inflating portions formed apart from each other in the vehicle width direction. And a central expansion part formed between the pair of head expansion parts, and a restriction part that restricts the flow of the gas toward the central expansion part and directs the gas flow toward the pair of head expansion parts. It is characterized by.

  According to this configuration, since the gas flow toward the central expansion part formed between the pair of head expansion parts is regulated and directed to the head expansion part, the gas flow is more than the head expansion part. Gas can flow in.

  According to a fourth aspect of the present invention, in the airbag apparatus for rear impact according to the third aspect, the internal inflating portion extends from the restricting portion to induce the inflow of the gas into the head inflating portion. It includes a guide part that performs.

  According to this configuration, the gas is guided by the guide portion and the gas flows smoothly into the head expansion portion, so that the head expansion portion expands and deploys more quickly.

  In the rear impact airbag device of the present invention, the portion of the airbag corresponding to the head of the passenger seated on the rear seat of the vehicle can be quickly filled with gas.

  DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments embodying the present invention will be described with reference to FIGS. In the following explanation, the forward direction of the vehicle is described as the front, and the front, rear, top, bottom, left, and right are defined on the basis of the forward direction. In the case of a seat, the state installed in the vehicle is the standard. In addition, front, rear, upper, lower, left, and right are defined corresponding to each direction of the vehicle. In FIG. 1, a rear seat 1 disposed at the rear of the vehicle is shown together with an occupant P sitting on the rear seat 1.

  As shown in FIG. 1, the above-described rear seat 1 includes a seat 2 that supports the thigh from the buttocks of the occupant P, a backrest 3 that is configured to be reclining, and a head of the occupant P from the backrest 3. And a headrest 4 extended so as to be able to support. Further, in this vehicle, for the purpose of protecting the occupant P seated on the rear seat 1, a rear-impact airbag device 10 having an airbag that inflates and deploys between the headrest 4 and the rear window 5 at the rear end of the vehicle. Is provided.

  The rear-impact airbag device 10 is inflated and deployed as shown by a two-dot chain line in FIG. 1, and an airbag 11 made of nonwoven fabric, and connected to the airbag 11 and a gas generation source for the inflation. The air bag 11 and the inflator 12 are disposed in the ceiling portion 30 of the vehicle. The inflator 12 is provided with an igniter (not shown) and a gas generating agent inside to generate gas to be supplied into the airbag 11, and is formed in a cylindrical shape that is long in the axial direction.

  Further, according to FIG. 2 showing a state in which the vehicle is viewed from the rear side, the airbag 11 is inflated and deployed so as to face the rear window 5 in the vehicle front-rear direction. And in this embodiment, in order to receive suitably the head of the passenger | crew P who seats on the rear seat 1 with the airbag 11, the following structures are employ | adopted. That is, in the airbag 11, the gas filling to the part of the rear seat 1 that opposes the pair of left and right headrests 4 in the front-rear direction, that is, the part corresponding to the head of the occupant P seated on the rear seat 1 is performed earlier. It is set so that the expansion is performed quickly. The detailed description will be described below with reference to FIGS. In the following description, a portion corresponding to the head of the occupant P seated on the rear seat 1 of the airbag 11 described above is referred to as a head inflating portion. FIG. 3 shows a state in which the airbag 11 is deployed before inflation, and FIG. 4 shows an arrangement of the airbag 11 in the ceiling portion 30.

  First, as shown in FIG. 3, the airbag 11 is formed so that the outer edge thereof has a fan shape, and the upper end portion 11 a is formed at the center in the vehicle width direction with the inflator 12 (see FIG. 1). A gas inflow portion 13 serving as a connection portion and serving as an entrance to the inside of the gas airbag 11 is provided. Further, the airbag 11 is attached to the vehicle by fixing a bolt inserted into a fixing portion 11b formed in the upper end portion 11a in the ceiling portion 30 (see FIG. 1). And the volume which can expand | swell rather than the airbag 11 is restrict | limited inside the airbag 11, The internal expansion part 14 formed with the nonwoven fabric similar to the airbag 11 is provided, This internal expansion part 14 is provided. Is configured to include the following parts.

  For example, a first lateral passage 15 is formed in the airbag 11 so as to extend on both sides in the vehicle width direction (left and right direction) at a portion closest to the gas inflow portion 13 of the internal inflation portion 14. A first longitudinal passage 16 extending downward is connected to both ends of the lateral passage 15 in the vehicle width direction. The gas ejected from the inflator 12 flows into the first horizontal passage 15 and the first vertical passage 16 at the earliest time in the airbag 11. A second lateral passage 17 extends in the vehicle width direction between the longitudinal passages 16 below the first lateral passage 15 of the airbag 11. A pair of second vertical passages 18 extend from both ends of the second horizontal passage 17 in the vehicle width direction toward the lower end portion of the airbag 11, and both end portions of the second horizontal passage 17 in the vehicle width direction. The pair of third vertical passages 19 extend from the inner side of the airbag 11 toward the lower end portion of the airbag 11 than the second vertical passage 18. Note that the head inflating portion corresponding to the head of the occupant P seated on the rear seat 1 described above is a portion indicated by 20 in the third vertical passage 19. Therefore, the head inflating portion 20 includes gas from the gas inflow portion 13 connected to the inflator 12 from above via the first lateral passage 15 and the second lateral passage 17, that is, the upper end side of the airbag 11. Inflow from.

  Further, in the airbag 11, a central inflating portion 21 is formed at a portion between a pair of third vertical passages 19 (head inflating portions 20) formed to be separated in the vehicle width direction. The central expansion portion 21 communicates with the third vertical passage 19 on both sides in the vehicle width direction, and a partition wall 22 that functions as a restricting portion is provided between the central expansion portion 21 and the second horizontal passage 17. Accordingly, the gas flowing into the second lateral passage 17 is restricted by the partition wall 22 from flowing downward (on the side of the central expansion portion 21), and enters the third vertical passage 19 where the head expansion portion 20 is located. It will flow in the direction.

  The airbag 11 thus formed is folded and accommodated in the ceiling portion 30 as shown in FIG. At this time, the position where the airbag 11 is accommodated is between the roof panel 31 facing the outside of the vehicle and the roof head lining 32 facing the vehicle interior, with respect to the inner panel 33 disposed therebetween. Thus, the airbag 11 is fixed by fastening the fixing portions 11b with the bolts 34, respectively. The roof head lining 32 has its rear end 32a on the vehicle rear side locked by a locking piece 35a extending from the weather strip 35, and the locked state by the locking piece 35a is released. As a result, the rear end side of the roof head lining 32 is opened.

  Next, the operation | movement aspect of the airbag apparatus 10 for rear collisions is demonstrated. When an impact of a predetermined value or more is applied from the rear of the vehicle, such as when another vehicle collides behind the vehicle, this is detected by a collision detection sensor (not shown), and a drive current is output from the control circuit to the inflator 12. Ignition is performed by the ignition device (not shown). As a result, gas is generated from the gas generating agent of the inflator 12, gas flows from the gas inflow portion 13 into the airbag 11, and the airbag 11 is inflated and deployed. And gas flows into the internal inflating part 14 of this airbag 11 in the order shown below. That is, first, gas flows into the first horizontal passage 15 from the gas inflow portion 13, and then gas flows into the first vertical passage 16 through the first horizontal passage 15. As described above, first, when the first horizontal passage 15 and the first vertical passage 16 are filled with gas and inflated, the airbag 11 is almost completely unfolded, and the outer edge shape of the airbag 11 is the same as when the occupant P is received. Since it becomes the same thing as a shape, the gas filling with respect to the other internal expansion part 14 after that comes to be performed smoothly.

  Next, the gas flows through the second horizontal passage 17 toward the outside in the vehicle width direction, first flows into the third vertical passage 19, and then flows into the second vertical passage 18. In the airbag 11, since the volume of expansion is increased in order to receive the occupant P as the passage on the lower end side thereof, gas is allowed to flow in from an upper portion thereof in a portion to be inflated early. Is an appropriate gas inflow mode. Accordingly, the head expansion portion 20 located in the third vertical passage 19 is filled with gas earlier than the second lateral passage 17 located on the upper side thereof, so that the internal expansion occurs earlier around this portion. The portion 14 expands so that the head of the occupant P can be received at an early point after the collision. A part of the gas flowing into the third vertical passage 19 flows into the central expansion portion 21 through the communication portion with the central expansion portion 21, and the central expansion portion 21 expands. And when this center inflating part 21 expand | swells, the rigidity of the center part at the time of inflation deployment of the airbag 11 improves, and the stability at the time of receiving the passenger | crew's P head by the head inflating part 20 also improves. It becomes like this.

  When the airbag 11 is inflated in this way, the roof head lining 32 is pushed downward by the pressing force generated by the inflation, and the vehicle rear side portion of the ceiling portion 30 is opened, and the airbag 11 is shown in FIG. As shown in FIG.

In the present embodiment described above, the following operational effects can be achieved.
(1) In the state where the airbag 11 is deployed, the internal inflation portion 14 includes a passage through which gas flows from above into the head inflation portion 20 that inflates and deploys corresponding to the head of the occupant P seated on the rear seat 1. Configure. Therefore, gas flows into the head inflating portion 20 from above, and the gas does not pass through the central inflating portion 21 on the lower end side of the airbag 11 having a relatively large inflation volume. Can be filled quickly.

  (2) In the state where the airbag 11 is deployed, the first lateral passage 15 connected to the gas inflow portion 13 into which the gas from the inflator 12 flows and extended in the left-right direction of the vehicle, and both ends of the lateral passage 15 The internal expansion portion 14 is configured to include a first vertical passage 16 that is connected to each portion and extends downward. Therefore, first, the first transverse passage 15 connected to the gas inflow portion 13 is filled with gas, and then the expansion and deployment of the first longitudinal passage 16 is completed, so that the folding of the entire airbag 11 is appropriately released. As a result, the shape is stabilized, and the subsequent filling of gas proceeds smoothly. Then, since the expansion of the head inflatable portion 20 is completed thereafter, the head inflatable portion 20 is smoothly filled at an early stage, and the head inflatable portion 20 is stably inflated and deployed. Will be able to.

  (3) A pair of third vertical passages 19 (head inflating portions 20) formed apart from each other in the vehicle width direction, and a central inflating portion 21 formed between the pair of third vertical passages 19, The internal expansion portion 14 is configured to include the partition wall 22 that restricts the flow of gas toward the central expansion portion 21 and directs it toward the pair of third vertical passages 19. Accordingly, the flow of gas toward the central expansion portion 21 formed between the pair of third vertical passages 19 is restricted and directed toward the third vertical passage 19. Many gases can be introduced.

In addition, this embodiment can also be implemented with the following forms which changed this suitably.
In the above embodiment, the central expansion portion 21 is provided between the pair of third vertical passages 19 and the partition wall 22 between the second horizontal passage 17 and the central expansion portion 21 is provided. For example, as shown in FIG. In addition, in the airbag 11 having no central inflating portion, such a partition wall can be omitted.

  Further, if at least most of the gas can flow into the head expansion portion 20 without providing a partition so that the flow of gas from the second lateral passage 17 to the central expansion portion 21 is completely blocked. The arrangement of the partition walls 22 can be changed as appropriate.

  In addition, the second vertical passage 18 can be omitted from the inner inflating portion 14 of the airbag 11. In this case, a configuration in which the entire airbag 11 is reduced in the vehicle width direction or the widths of the first vertical passage 16 and the third vertical passage 19 in the vehicle width direction can be employed.

  In addition, when the shape of the airbag 11 itself is small and can be disposed in the ceiling portion 30 without being folded, the airbag can be omitted even if the first horizontal passage 15 and the first vertical passage 16 are omitted. Since there is little influence on the deterioration of the deployment performance, these can be omitted.

  In addition to the third vertical passage 19 where the head inflating portion 20 is located, in addition to the passage through which gas flows from above, that is, from the upper end side of the airbag 11, for example, between the second vertical passage 18 It is also possible to form a communication passage in the vehicle so as to flow in from the vehicle width direction side.

  Further, as shown in FIG. 5, the second vertical passage 18 and the third vertical passage 19 communicate with each other on the lower end side of the airbag 11 so that the gas flows from the communication portion to the central inflating portion 21. A simple airbag 11 can also be employed. In this case, the guide part which guides the inflow of the gas to the 3rd vertical path 19 (head expansion part 20) by extending the partition 22 without making the 3rd vertical path 19 and the center expansion part 21 communicate directly. It can also be made to function as 24.

  Further, assuming that three passengers are seated on the rear seat 1, three head inflating portions are formed, between the left side in the vehicle width direction and the pair of head inflating portions on the center side, the right side in the vehicle width direction, A central expansion part can also be formed between each of the pair of head expansion parts on the center side.

The side view which shows the rear part of the vehicle by which the airbag apparatus for rear collisions concerning this invention is mounted from a side. Similarly, the rear view which shows the vehicle by which the airbag apparatus for rear collisions is mounted from the back side. Similarly, the front view which shows the expansion | deployment state before the expansion | swelling of the airbag used in the airbag apparatus for rear collisions. Similarly, sectional drawing which shows the arrangement | positioning aspect in the ceiling part of the airbag apparatus for rear collisions. The front view which shows the modification of the airbag used in the airbag apparatus for rear collision in the unfolded state before the expansion | swelling. The front view which shows the modification of the airbag used in the airbag apparatus for rear collision in the unfolded state before the expansion | swelling.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Rear seat, 10 ... Air bag apparatus for rear collisions, 11 ... Air bag, 12 ... Inflator, 13 ... Gas inflow part, 14 ... Internal expansion part, 15 ... 1st horizontal passage, 16 ... 2nd vertical passage, 17 ... 2nd horizontal passage, 18 ... 2nd vertical passage, 19 ... 3rd vertical passage, 20 ... Head expansion part, 21 ... Center expansion part, 22 ... Partition, 24 ... Guide part.

Claims (4)

The airbag is inflated from the top to the bottom of the vehicle by filling the inflated portion formed inside the airbag housed in the ceiling of the vehicle with the gas ejected from the inflator serving as the gas generation source. In the rear impact airbag device to be deployed,
The internal inflating portion includes a passage through which the gas flows from above into a head inflating portion that inflates and deploys corresponding to the head of an occupant seated on a rear seat when the airbag is deployed. Air bag device for rear impact. In the airbag apparatus for rear collisions of Claim 1,
The internal inflating portion is connected to a gas inflow portion into which gas from the inflator flows in in a state where the airbag is deployed, and extends in the left-right direction of the vehicle, and at both ends of the horizontal passage. A rear impact airbag device comprising: a longitudinal passage connected to each other and extending downward. In the rear-impact airbag device according to claim 1 or 2,
The internal expansion portion includes a pair of head expansion portions formed apart from each other in the vehicle width direction, a central expansion portion formed between the pair of head expansion portions, and the head toward the central expansion portion. And a restricting portion that restricts a gas flow and directs the gas flow toward the pair of head inflating portions. In the airbag apparatus for rear impacts of Claim 3,
The internal inflation part includes a guide part that extends from the restricting part and guides the inflow of the gas into the head inflating part.

Images