JP2008162327A - Airbag system for rear end collision - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To stably inflate and develop an airbag in an airbag system for a rear end collision. <P>SOLUTION: In this airbag system for a rear end collision, an interior inflation portion 14 includes a vertical inflation portion 15 which is arranged along the release direction of an airbag folded in the vertical direction of a vehicle when an airbag 11 is developed and connected to a gas inlet port 13 from an inflator, and horizontal inflation portions 16a-16d which are branched from the vertical inflation portion 15 and independently arranged near both ends in the vehicle width direction of the airbag 11. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  According to the present invention, an air bag is mainly provided by filling a gas blown from an inflator serving as a gas generation source into an internal inflating portion formed inside an air bag folded and accommodated in a ceiling of a vehicle. The present invention relates to a rear impact airbag device that inflates and deploys a vehicle from above to below.

  Various occupant protection devices have been proposed for vehicles to ensure safety in the event of a collision. As a representative example of such an occupant protection device, for example, an airbag device described in Patent Document 1 or Patent Document 2 is used. Can be mentioned. In these airbag devices, 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 passenger compartment at the rear of the vehicle, that is, from above to below.

  More specifically, in the airbag device described in Patent Document 1, a flow path for inflation is formed in the airbag, and gas flows along the flow path. Gas flows downward along the flow path formed at both ends in the vehicle width direction of the airbag, and the right and left flow paths extend in the vehicle width direction between the flow paths at both ends in the vehicle width direction. Gas flows from the flow paths at both ends.

Moreover, in the airbag apparatus described in Patent Document 2, the airbag inflation gas ejected from the inflator is quickly diverted to the vehicle width direction both ends and the center through the supply pipe. And in these vehicle width direction both ends and center, gas flows in into the inside of an air bag from the upper part to the lower part.
JP 2004-284423 A JP 2004-359209 A

  By the way, when controlling the flow of gas as described above, a situation may occur in which the airbag is not stably inflated and deployed depending on the flow mode of the gas. For example, in the case of the airbag device described in Patent Document 1, since gas flows in from both ends of the airbag in the vehicle width direction, the gas inflow timing with respect to the central portion of the airbag is relatively delayed. In an airbag that is folded and accommodated in the ceiling of the vehicle in this way, it is desirable to first release the folding at the central portion in order to fill the airbag without biasing the gas, as described above. When the inflow of gas to the central portion of the airbag is delayed, the airbag is not properly released from folding.

  Further, in the airbag device described in Patent Document 2, although gas flows into the central portion of the airbag at an early stage, each portion communicates with other flow paths at a plurality of locations. Will flow from a plurality of directions. For this reason, the inflation mode of the airbag becomes complicated, and there is still room for improvement in the stability of the inflation.

  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 capable of stably inflating and deploying an airbag.

  In order to solve the above-mentioned problem, the invention according to claim 1 is ejected from an inflator serving as a gas generation source with respect to an internal inflating portion formed inside an airbag folded and accommodated in a vehicle ceiling. 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 with the gas, the internal inflation portion is arranged in the vertical direction of the vehicle when the airbag is deployed. A longitudinal inflating portion that extends along the release direction of the fold and is connected to the gas inlet from the inflator, and both ends of the airbag in the vehicle width direction are branched from the longitudinal inflating portion and are independent of each other. And a laterally expanded portion extending to the vicinity.

  According to this configuration, since the vertical inflation portion is first filled with gas and inflated, the folding of the airbag in the vehicle vertical direction is released starting from this portion. That is, since folding is released from a portion of the airbag that is not at both ends in the vehicle width direction and gas is filled, it is possible to suppress the inflow of gas from being extremely biased to either end. In addition, the gas that has flowed into the vertical expansion portion flows into each horizontal expansion portion, so that the horizontal expansion portion starts to expand, but the horizontal expansion portions are independently arranged, and gas is only supplied from the vertical expansion portion. Since it is not filled, the expansion timing and gas inflow mode can be appropriately controlled. Therefore, the airbag can be stably inflated and deployed.

  According to a second aspect of the present invention, in the airbag device for rear impact according to the first aspect, the vertical inflating portion is extended at the center of the airbag in the vehicle width direction, and the lateral inflating portion is It is extended so that it may become symmetrical in a vehicle width direction on the basis of the said vertical expansion part.

  According to this configuration, the longitudinally inflating portion extends in the center in the vehicle width direction, and the lateral inflating portion extends so as to be symmetric in the vehicle width direction with respect to the longitudinal inflating portion, so that the entire airbag is uniform. Gas can flow into the air bag, and the airbag can be inflated and deployed more stably.

  According to a third aspect of the present invention, in the airbag apparatus for rear impact according to the first aspect, the vertical inflating portion is set as a seating position for an occupant in a rear seat disposed on the rear side of the vehicle. The gist is that a plurality of the lateral inflating portions are extended corresponding to the portions, and the lateral inflating portions are extended so as to be symmetrical with respect to the center in the vehicle width direction of the airbag.

  According to this configuration, since the vertical inflating portion is inflated and deployed so as to correspond to the occupant seated on the rear seat, the occupant can be appropriately received by the vertical inflating portion, and the lateral inflating portion is in the vehicle width direction of the airbag. Since it extends so as to be symmetric in the vehicle width direction with respect to the center, gas can flow in uniformly through the entire airbag so that the airbag can be inflated and deployed more stably. Become.

  According to a fourth aspect of the present invention, in the rear-impact airbag device according to any one of the first to third aspects, the lateral inflating portion is extended at a position closest to the inflow port. The diameter of the expansion part is set to be smaller than the diameters of the other lateral expansion parts.

  In the state where the airbag is folded in the vehicle width direction, the filling of gas into the folded inflated portion is restricted. Therefore, in order to quickly fill the airbag with gas, the airbag is first folded. It is desirable to inflate the inflating part so that the is released. In this respect, according to the same configuration, the diameter of the lateral expansion portion closest to the gas inlet from the inflator is smaller than the diameters of the other lateral expansion portions. Inflates to. And since the folding of the airbag in the vehicle width direction is released along with the inflation, the gas filling into the inflating portion located on the lower end side of the airbag from the lateral inflating portion is performed smoothly thereafter. Become.

  Further, as in the configuration according to claim 5, the airbag has an upper end portion in a state where the airbag is deployed in the vehicle width direction is fixed in the ceiling, and is closest to the inflow port among the lateral inflating portions. Even if the inflating portion extending from the vertical inflating portion at the position is extended from the vertical inflating portion to the portion fixed to the outermost side in the vehicle width direction of the upper end portion, Inflation occurs earlier.

  The invention according to claim 6 is the airbag apparatus for rear impact according to any one of claims 1 to 5, wherein the laterally inflating portion has a distal end portion that is folded in the vertical direction of the airbag. It is characterized by being directed toward the direction side.

  The deployment of the folding of the airbag along the vertical direction of the vehicle is performed mainly by the expansion of the vertical expansion portion, but when the lateral expansion portion has only a portion extending in the vehicle width direction, the vehicle width direction of the airbag There is a case where the release of the folding in the vehicle vertical direction at both ends is not smoothly performed. Therefore, as described above, the front end of the lateral expansion portion is oriented in the folding direction of the vehicle in the vertical direction of the vehicle, so that the vertical folding of the both end portions in the vertical direction is smoothly performed as this portion expands due to gas filling. Will be released.

  Further, if the lateral expansion portions are extended so as to be parallel to each other in the vehicle width direction, a portion not filled with gas is generated between the lateral expansion portions. If the force acting when the airbag receives the occupant concentrates on this part, the airbag may be bent at this part, which is not preferable. On the other hand, the tip of the lateral expansion portion is oriented in the folding direction in the vertical direction of the vehicle as in the above configuration, so that the tip is interposed at this portion, and the rigidity is improved by filling with gas. Thus, the airbag can be prevented from bending.

  The invention according to claim 7 is the rear impact airbag device according to claim 6, wherein the shape of the airbag is set in accordance with the extension regions of the longitudinally inflating portion and the laterally inflating portion, In the deployed state before inflation, the vertical dimension of the airbag is set to be larger at the center than at both ends in the vehicle width direction.

  By the way, when the expansion part changes from the unfolded state before the expansion to the expanded state, the dimension in the direction perpendicular to the direction in which the height increases with the expansion decreases in the vicinity of the end part. Therefore, as described above, when the front end portion of the lateral expansion portion is directed to the development direction side of the vertical folding, the contraction in the vertical direction of this portion is compared with the contraction of other portions of the lateral expansion portion. Get smaller. Therefore, if the shape of the airbag is set in accordance with the extension region of the inflating portion, and the shape of the airbag is set to a rectangle, the air is filled when the inflating portion is filled with gas and inflated. The vertical dimension of the bag is smaller at the center in the vehicle width direction than at both ends. Therefore, by adjusting the size of the airbag in the deployed state before inflating as in the above configuration, it is possible to suppress the displacement of the end position of the airbag in the inflated state and realize appropriate inflated deployment of the airbag Will be able to.

  According to the rear impact airbag device of the present invention, the timing of inflation of the airbag and the inflow mode of the gas can be appropriately controlled, so that the airbag can be stably inflated and deployed.

(First embodiment)
Hereinafter, a first embodiment of 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.

  This 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 is connected to the airbag 11 to generate the inflation gas. The air bag 11 and the inflator 12 are disposed in the ceiling portion 20 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.

  Next, the specific configuration and arrangement of the airbag 11 will be described with reference to FIGS. 2 shows the unfolded state in which the airbag 11 is unfolded, and FIGS. 3A and 3B show the order of folding the airbag 11. Further, FIG. The arrangement | positioning aspect of the airbag 11 is shown.

  As shown in FIG. 2, the airbag 11 is formed so that its outer edge has a fan shape, and is connected to the inflator 12 (see FIG. 1) at the center of the upper end portion 11a in the vehicle width direction. An inflow port 13 which is a part and serves 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 20 (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.

  The internal inflating portion 14 is connected to the inlet 13 at the center of the airbag 11 in the vehicle width direction and extends vertically from the inflow port 15. The internal inflating portion 14 branches from the vertical inflating portion 15 and is independent from each other. In this state, the airbag 11 includes lateral inflating portions 16a to 16d that extend to the vicinity of both ends in the vehicle width direction. Among these laterally inflating portions 16a to 16d, the lateral inflating portion 16a closest to the upper end portion 11a (inlet 13) of the airbag 11 is an upper end portion from the longitudinal inflating portion 15 toward both ends in the vehicle width direction of the airbag 11. It extends substantially parallel to 11a. Further, the lateral inflating portions 16 b to 16 c extend from the longitudinal inflating portion 15 toward both ends in the vehicle width direction of the airbag 11 substantially in parallel with the lateral inflating portion 16 a, and a tip portion thereof is a lower end of the airbag 11. It is bent and extended toward the side. The lateral inflating portion 16d extends from the lower end portion of the longitudinal inflating portion 15 toward both ends of the airbag 11 in the vehicle width direction so as to be positioned between the distal end portions of the pair of lateral inflating portions 16c. .

  Moreover, the diameter L1 at the time of the expansion | swelling with which the gas of the horizontal expansion part 16a was filled is set so that it may become small compared with the diameters L2-L4 at the time of expansion | swelling of the other horizontal expansion parts 16b-16d. Further, the lateral expansion portion 16a extends from the vertical expansion portion 15 to the fixed portion 11b on the outermost side in the vehicle width direction of the upper end portion 11a. Since it is not preferable to form the side edge in the vehicle width direction of the airbag 11 inside the fixed portion 11b on the outermost side in the vehicle width direction of the airbag 11, the position of the fixed portion 11b on the outermost side in the vehicle width direction is not preferable. By forming a side edge of the airbag 11 and extending the lateral inflating portion 16a to the side edge, the volume of the lateral inflating portion 16a is limited to be small in a suitable manner.

  Thus, the extended lateral inflating portions 16 a to 16 d are symmetrical in the vehicle width direction with respect to the longitudinal inflating portion 15, and therefore the longitudinal inflating portion 15 is positioned at the center in the vehicle width direction of the airbag 11. Coupled with this, the airbag 11 is filled with gas without being biased in either of the vehicle width directions. The shape of the airbag 11 is set in accordance with the extension region of the internal inflating portion 14. In other words, the internal inflatable portion 14 extends to the outer edge of the airbag 11, and thus, the shape of the airbag 11 when inflated and deployed is suitably maintained by the inflated internal inflatable portion 14. .

  By the way, as described above, the distal end portions of the lateral inflating portions 16b and 16c are bent so as to be directed downward of the airbag 11, and the shape of the airbag 11 is matched to the extension region of the internal inflating portion 14. When set, the following problems occur. That is, when the internal expansion portion 14 changes from the expanded state before expansion to the expanded state, the dimension in the direction perpendicular to the direction in which the height of expansion expands with expansion decreases in the vicinity of the end portion. Therefore, as described above, when the distal end portions of the lateral expansion portions 16b and 16c are directed to the development direction side of the vertical folding, the contraction in the vertical direction of this portion is the contraction in the vertical direction of the lateral expansion portion 16d. It becomes small compared. In this case, if the shape of the airbag is set to be rectangular, when the internal inflation portion 14 is filled with gas and inflated, the size of the airbag in the vertical direction is compared with the center portion in the vehicle width direction compared to both ends. Become smaller. Therefore, by adjusting the vertical dimension of the airbag 11 in the deployed state before inflating so that the center part is larger than both ends in the vehicle width direction, the lower end position of the airbag 11 in the inflated state is shifted. Thus, the airbag 11 can be appropriately inflated and deployed.

  Next, the airbag 11 thus configured is first folded in the manner shown in FIG. First, as shown in FIG. 3 (a), the airbag 11 is folded in a roll shape from the lower end side toward the upper end portion 11a, and then is folded in a bellows shape only the last few times. In such a folded state, the portion of the lateral expansion portion 16a is not folded, and therefore gas flows smoothly into this portion, so that the expansion of the lateral expansion portion 16a is completed earlier. Is set. Then, as shown in FIG. 3 (b), the both ends in the vehicle width direction of the folded and substantially cylindrical portion are folded twice so as to be folded.

  And the folded airbag 11 is accommodated in the ceiling part 20 as FIG. 4 shows. At this time, the position in which the airbag 11 is accommodated is between the roof panel 21 facing the outside of the vehicle and the roof head lining 22 facing the vehicle interior, with respect to the inner panel 23 disposed therebetween. Thus, the airbag 11 is fixed by fastening the fixing portions 11b with the bolts 24, respectively. The roof head lining 22 has its rear end 22a on the vehicle rear side locked by a locking piece 25a extending from the weather strip 25, and the locked state by the locking piece 25a is released. As a result, the rear end side of the roof head lining 22 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, and the gas flows into the airbag 11 from the inflow port 13, and the airbag 11 is inflated and deployed.

  At this time, first, in the airbag 11, gas is filled into the longitudinally inflating portion 15, and the release of the bellows fold of the airbag 11 corresponding to this portion proceeds in the vertical direction, and is divided from the longitudinal inflating portion 15. When the gas is filled, the lateral expansion portion 16a also starts to expand. At this time, the lateral expansion portion 16a is not folded as described above, and since the expansion volume is limited to be small, the expansion is completed at an early stage. Accordingly, since the airbag 11 is quickly deployed in the vehicle width direction on the fixed upper end portion 11a side, the subsequent inflation and deployment in the vertical direction is performed while being supported by the lateral inflation portion 16a, and the inflation as a whole is performed. Deployment will be performed stably.

  Further, since the vertical inflating portion 15 is filled with gas and inflated, the folding of the airbag 11 in the vehicle vertical direction is released starting from this portion. That is, since folding is released from a portion of the airbag 11 that is not at both ends in the vehicle width direction and the gas is filled, it is possible to suppress the inflow of gas from being extremely biased to either end. . Moreover, although the gas which flowed into the vertical expansion part 15 flows into each horizontal expansion part 16a-16d, horizontal expansion part 16a-16d starts expansion | swelling, but horizontal expansion part 16a-16d is each arrange | positioned independently. Since the gas is filled only from the vertical expansion portion 15, the expansion timing and the gas inflow mode can be appropriately controlled. Therefore, the airbag 11 can be stably inflated and deployed. Further, the release of the folding in the vertical direction at both ends of the airbag 11 in the vehicle width direction is because the front ends of the laterally inflating portions 16b and 16c are directed to the lower side of the airbag 11, and this portion is filled with gas. Assisted by the inflating, the folding in the vertical direction of both end portions of the vehicle width of the airbag 11 is also smoothly released.

  When the airbag 11 is inflated in this way, the roof head lining 22 is pushed downward by the pressing force generated by the inflation, and the vehicle rear side portion of the ceiling portion 20 is opened, and the airbag 11 is released from this portion. It will be deployed in the passenger compartment. Then, as shown in FIG. 5, the airbag 11 is inflated and deployed in a uniform manner so that the lower end portion of the airbag 11 is substantially straight. When the occupant P seated on the rear seat 1 is displaced toward the rear side of the vehicle and comes into contact with the airbag 11, a force acts on the airbag 11 from the occupant P. When this force is concentrated on a relatively low rigidity portion (for example, a portion between the lateral inflating portion 16b and the lateral inflating portion 16c) located between the inner inflating portions 14 of the airbag 11, this portion is bent, There is a possibility that the head of the occupant P cannot be properly received. However, in this embodiment, since the distal end portion of the lateral inflating portion 16b is interposed at this portion, the lateral inflating portion 16b is filled with gas and its rigidity is improved, thereby suppressing the bending of the airbag 11. Will be able to.

The rear impact airbag device 10 according to the present embodiment described above can achieve the following effects.
(1) In the state in which the airbag 11 is deployed, the longitudinal inflating portion 15 that extends along the release direction of the vertical folding of the vehicle and is connected to the gas inlet 13 from the inflator 12, The internal inflating portion 14 is configured to include the lateral inflating portions 16a to 16d that branch from the inflating portion 15 and extend to the vicinity of both ends in the vehicle width direction of the airbag 11 in an independent state. Therefore, since the vertical inflating portion 15 is first filled with gas and inflated, the folding of the airbag 11 in the vehicle vertical direction is released starting from this portion. That is, since folding is released from a portion of the airbag 11 that is not at both ends in the vehicle width direction and the gas is filled, it is possible to suppress the inflow of gas from being extremely biased to either end. . Moreover, although the gas which flowed into the vertical expansion part 15 flows into each horizontal expansion part 16a-16d, horizontal expansion part 16a-16d starts expansion | swelling, but horizontal expansion part 16a-16d is each arrange | positioned independently. Since the gas is filled only from the vertical expansion portion 15, the expansion timing and the gas inflow mode can be appropriately controlled. Therefore, the airbag 11 can be stably inflated and deployed.

  (2) The vertical inflating portion 15 extends in the vertical direction at the center of the airbag 11 in the vehicle width direction, and the lateral inflating portions 16a to 16d extend so as to be symmetric in the vehicle width direction with respect to the vertical inflating portion 15. It was decided to. As a result, the gas flows uniformly into the entire airbag 11 and the airbag 11 can be inflated and deployed more stably.

  (3) Of the lateral expansion portions 16a to 16d, the diameter L1 of the lateral expansion portion 16a extending at the position closest to the inflow port 13 is compared with the diameters L2 to L4 of the other lateral expansion portions 16b to 16d. Therefore, it was decided to set a small diameter. Further, the lateral inflating portion 16a is extended from the longitudinal inflating portion 15 to the fixing portion 11b that is fixed to the outermost side in the vehicle width direction of the upper end portion 11a of the airbag 11. Accordingly, the lateral expansion portion 16a can be expanded quickly toward both ends in the vehicle width direction, and the folding in the vehicle width direction can be released early during this expansion. Therefore, the gas filling into the other lateral expansion parts 16b to 16d (particularly the folded lateral expansion parts 16b and 16c) is smoothly performed.

  (4) The lateral inflatable portions 16b and 16c are formed so that the tip portions thereof are directed toward the folding deployment direction side (that is, the lower end side) of the airbag 11 in the vertical direction. As described above, the folding of the airbag 11 along the vertical direction of the vehicle is performed mainly by the expansion of the vertical expansion portion 15, but only the portions where the horizontal expansion portions 16a to 16d are extended in the vehicle width direction. If not, the folding in the vehicle vertical direction at both ends of the airbag in the vehicle width direction may not be smoothly performed. Therefore, by orienting the front ends of the lateral inflating portions 16b and 16c in the folding direction in the vertical direction of the vehicle, the upper and lower ends of both ends of the airbag 11 in the vehicle width direction as this portion expands due to gas filling. The folding in the direction is smoothly released.

  Further, by orienting the front ends of the lateral inflating portions 16b and 16c in the folding direction of the airbag 11 along the vertical direction of the vehicle, between the lateral inflating portion 16b and the lateral inflating portion 16c, This tip is interposed between the lateral inflating portion 16d and the gas 11 is filled to improve its rigidity, so that the airbag 11 can be prevented from bending.

  (5) The shape of the airbag 11 is set in accordance with the extension regions of the longitudinal inflating portion 15 and the lateral inflating portions 16a to 16d, and the vertical dimension of the airbag 11 in the deployed state before inflating is the both ends in the vehicle width direction. The central part is set larger than the part. Therefore, by adjusting the dimensions of the airbag 11 in the deployed state before inflating in this way, the displacement of the lower end portion of the airbag 11 in the inflated state is suppressed, and the airbag 11 is appropriately inflated and deployed. Will be able to.

In addition, this embodiment can also be implemented with the following forms which changed this suitably.
In the above-described embodiment, the front end portions of the lateral inflating portions 16b and 16c are directed toward the lower end portion side of the airbag 11. However, as shown in FIG. A configuration in which the portions 36a to 36d extend from the longitudinal expansion portion 35 only in the vehicle width direction can also be employed. Even in this case, it is possible to achieve the same effects as the above (1), (2) and (3). Further, as shown in FIG. 8, if the distance between the lateral inflating portions 46a to 46d of the airbag 40 is narrowed, even if a force is applied when the occupant P is received on this portion, the air is The bag 11 can be prevented from bending. In such a case, since the vertical contraction of the airbags 30 and 40 during the inflation and deployment of the airbags 30 and 40 does not differ between the center and both ends in the vehicle width direction, the lower ends of the airbags 30 and 40 are linear before the inflation. The airbags 30 and 40 can be configured to be

  In the above-described embodiment, the lateral inflating portion 16a is extended to a portion located on the outermost side in the vehicle width direction among the fixing portions 11b of the airbag 11. However, this can be changed to the configuration shown in FIG. It is. That is, the laterally inflated portion 56a of the airbag 50 is extended to the vehicle outer side than the portion of the fixed portion 51b that is located on the outermost side of the vehicle, and the tip of the extended portion is further directed to the lower end side of the airbag 50. I decided to make it point. Even if the airbag 50 is configured in this manner, an effect equivalent to that obtained by removing (3) from (1) to (5) described above can be achieved. In addition, the speed of completion of the expansion in the lateral inflating portions 16a, 36a, 46a, and 56a described above varies depending on factors such as factors affecting the volume of the part, the gas inflow mode, and the like. It should be appropriately changed according to the required value required according to the overall configuration.

  In addition, the method of folding the airbag 11 is not limited to the above-described one, and only the bellows fold or the roll-like fold is adopted, or the airbag is folded in the vehicle width direction when the width in the vehicle width direction is small. It can be omitted. Moreover, if folding of the airbag in the vehicle width direction is applied to the lateral inflating portion on the upper end portion side where the airbag is fixed, the inflating portion is inflated to release the folding in the vehicle width direction at an early stage. Will be able to.

Further, a material different from the material of the airbag 11 may be employed as the material of the internal inflating portion 14, and for example, it is more preferable to use a material that is more difficult to break in terms of strength.
In the above embodiment, the airbag 11 is formed so as to be symmetric in the vehicle width direction with respect to the longitudinal inflating portion 15, but the lateral inflating portions 16a to 16d on one side are longer than the lateral inflating portions 16a to 16d on the other side. Even in this case, if the gas is not excessively biased to flow in either direction of the vehicle width of the airbag 11, the inflation stability of the airbag 11 can be prevented from being lost as much as possible.

  In addition, the number of laterally inflated portions and the number of vertically inflated portions can be changed as appropriate according to the size and shape of the airbag. For example, when the airbag is long in the vehicle width direction, two vertical expansion portions connected to the gas inlet are arranged side by side so as to be aligned in the vehicle width direction, and the left side expansion portion on the left side in the vehicle width direction is arranged on the left side. It is also possible to adopt a configuration in which gas is allowed to flow from the vertical expansion portion, and gas is allowed to flow from the right vertical expansion portion to the right lateral expansion portion in the vehicle width direction.

  In addition, for a seat on which a plurality of people are seated like a rear seat, for example, the following configuration can be adopted. That is, in the rear seat, a plurality of vertical inflating portions are extended corresponding to the seating portion set as a position where the occupant is seated, and the lateral inflating portions are extended symmetrically with respect to the center in the vehicle width direction of the airbag. I decided to. In this case, since the vertical inflating portion is inflated and deployed so as to correspond to the occupant seated on the rear seat, the occupant can be appropriately received by the vertical inflating portion, and the lateral inflating portion is based on the center in the vehicle width direction of the airbag. As a result, the gas flows uniformly through the entire airbag, and the airbag can be inflated and deployed more stably. Moreover, the number of the longitudinal expansion parts can be changed as appropriate, and may be changed according to the assumed number of passengers.

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 front view which shows the expansion | deployment state before the expansion | swelling of the airbag used in the airbag apparatus for rear collisions. (A), (b) is a front view which similarly shows the folding procedure of an airbag. Similarly, sectional drawing which shows the arrangement | positioning aspect in the ceiling part of the airbag apparatus for rear collisions. Similarly, the top view which shows the airbag in the state which was filled with gas and inflate-deployed. The front view which shows the modification of the airbag in the state which expand | deployed before inflation. The front view which shows the modification of the airbag in the state which expand | deployed before inflation. The front view which shows the modification of the airbag in the state which expand | deployed before inflation.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 ... Air bag apparatus for rear collisions 11, 30, 40, 50 ... Air bag, 11a ... Upper end part, 11c ... End part, 12 ... Inflator, 13 ... Inlet, 14 ... Internal expansion part, 15, 35 ... Vertical Expansion part, 16a-16d ... Lateral expansion part.

Claims (7)

The air bag is lowered from the upper side of the vehicle by filling the inflated portion formed inside the airbag folded and accommodated in the ceiling of the vehicle with a gas ejected from an inflator serving as a gas generation source. In the rear impact airbag device that is inflated and deployed toward the
The internal inflatable portion extends along the release direction of the vertical folding of the vehicle in a state where the airbag is deployed, and is connected to a gas inflow port from the inflator. And a laterally inflating part that branches from the longitudinally inflating part and extends to the vicinity of both ends in the vehicle width direction of the airbag in an independent state. In the airbag apparatus for rear collisions of Claim 1,
The longitudinally expanded portion is extended at the center of the airbag in the vehicle width direction,
The laterally inflating portion is extended so as to be symmetrical in the vehicle width direction with respect to the longitudinally inflating portion. In the airbag apparatus for rear collisions of Claim 1,
The vertical expansion portion is extended in plural corresponding to the seating portion set as the seating position of the occupant in the rear seat disposed on the vehicle rear side,
The laterally inflating portion is extended so as to be symmetrical with respect to a vehicle width direction center of the airbag. In the airbag apparatus for rear collisions as described in any one of Claims 1-3,
Of the lateral expansion parts, the diameter of the expansion part extending at a position closest to the inflow port is set to be smaller than the diameters of the other lateral expansion parts. Air bag device. In the airbag apparatus for rear collisions as described in any one of Claims 1-4,
The airbag has an upper end fixed in the ceiling in a state of being deployed in the vehicle width direction,
Of the lateral expansion portion, an expansion portion extending from the vertical expansion portion at a position closest to the inflow port extends from the vertical expansion portion to a portion fixed to the outermost side in the vehicle width direction of the upper end portion. A rear-impact airbag device characterized by being provided. In the airbag device for rear impacts according to any one of claims 1 to 5,
The laterally inflating portion has a front end portion directed toward a deployment direction of folding in the vertical direction of the airbag. In the airbag apparatus for rear collisions of Claim 6,
The shape of the airbag is set in accordance with the extending regions of the longitudinally inflating part and the laterally inflating part, and the size of the airbag in the up-down direction before inflating is larger than the both end parts in the vehicle width direction. A rear-impact airbag device characterized in that a central portion is set to be large.

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