JP5273016B2 - Gas distribution structure of airbag device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To restrain influence of heat by lowering the temperature of gas, while exhibiting the function of distributing the gas jetted from a gas jetting part of an inflator. <P>SOLUTION: The gas distribution structure distributes the gas G jetted from the gas jetting part 24 of the inflator 21 to two inflating parts of an airbag by pointing in the direction along the axis L by an inner tube 40. A pair of folding pieces 46 are formed as the inner tube 40 by bending a long size fabric web along a folding line 45, and both folding pieces 46 are mutually joined by a pair of joining parts 53 and 55 orthogonal to the folding line 45, to form an object of opening an edge part 57 opposed to the folding line 45. The inflator 21 is inserted into the inner tube 40 so that the gas jetting part 24 is positioned in a place deviated to the second joining part 55 side and the folding line 45 side of the inner tube 40, and a gas discharge hole 59 is arranged in a place near the first joining part 53 on the folding line 45. <P>COPYRIGHT: (C)2011,JPO&amp;INPIT

Description

  The present invention relates to a gas distribution structure of an airbag device that is applied to an airbag device using an airbag having a plurality of inflatable portions and distributes gas ejected from an inflator to each inflatable portion.

  A so-called airbag device that inflates an airbag with a gas supplied from an inflator in response to the impact when the vehicle is subjected to an impact due to a collision or the like is effective. . Further, in an airbag device using an inflator having an inflating portion at two different locations along the axis as an air bag, an appropriate amount of gas jetted from the gas jetting portion of the inflator is supplied to each inflating portion. is important. Accordingly, various airbag devices have been proposed in which an inner tube is disposed in the airbag and an inflator is inserted into the inner tube.

  For example, in the side airbag device described in Patent Document 1, the airbag is partitioned into two inflating parts in the vertical direction. As the inner tube, one that extends in the vertical direction and is open at both upper and lower ends is used, and the inner tube is positioned so that the upper open end is located in the upper inflatable portion and the lower open end is located in the lower inflatable portion. A tube is disposed in the airbag. Further, an inflator having a gas ejection portion at the lower end is inserted into the inner tube. The inner tube in which the inflator is inserted is inserted into the retainer, and is fixed to a mounting portion (vehicle seat) in the vehicle compartment together with the retainer and the airbag. In this side airbag device, the gas ejected from the gas ejection portion of the inflator is supplied into the inner tube. This gas flows upward or downward in the inner tube, flows from the upper open end of the inner tube into the upper expanding portion, and flows from the lower open end into the lower expanding portion.

JP 2005-225351 A

  By the way, the gas ejected from the gas ejection portion of the inflator is formed by particles that are heated. For this reason, when these particles agglomerate and hit the vicinity of the gas ejection part in the inner tube or the airbag, a large amount of heat may be applied to the part and damage may occur. In order to reduce the influence of such heat, it is effective to lower the gas temperature.

  However, in the side airbag device described in Patent Document 1 described above, although the gas ejected from the gas ejection portion can be directed to the up and down direction and distributed to each expansion portion, the effect of lowering the gas temperature is I can hardly expect it.

  The present invention has been made in view of such circumstances, and its purpose is to reduce the temperature of the gas while exerting the function of distributing the gas ejected from the gas ejection portion of the inflator, and to influence the heat. It is an object of the present invention to provide a gas distribution structure of an airbag device that can suppress the above-described problem.

  In order to achieve the above object, an invention according to claim 1 is an airbag device comprising a long inflator and an airbag having inflatable portions at two different locations along at least an axis of the inflator. A gas distribution structure of an airbag device that is applied to the inflator and distributes the gas ejected from a gas ejection portion of the inflator to each inflatable portion by directing the gas in a direction along the axis by an inner tube. The fabric was folded along a fold line intersecting the longitudinal direction thereof to form a pair of fold pieces, and the both fold pieces were provided along one edge portion intersecting the fold line of the fabric. Edges that are joined to each other by the first joint and are joined to each other by the second joint provided along the other edge that intersects the fold line of the fabric and faces the fold line Is formed, and the inflator is inserted into the inner tube so that the gas jetting portion is located at a location offset to the second joint portion side and the fold line side of the inner tube. Furthermore, the gist is that a gas discharge hole is provided at a location near the first joint on the fold line.

  According to the above configuration, most of the gas ejected from the gas ejection part of the inflator in the inner tube flows separately in the direction along the axis of the inflator and in the direction substantially orthogonal to the coaxial line in the inner tube. . Most of the gas flowing in the direction along the axis collides with the vicinity of the fold line of the inner tube. A part of the gas flowing in the direction substantially orthogonal to the axis collides with the vicinity of the first joint portion or the vicinity of the second joint portion of the inner tube. These collisions change the gas flow direction. This change consumes gas energy, and the temperature of the gas decreases accordingly.

  Further, in the inner tube, some turbulence is generated by changing the gas flow direction in the vicinity of the gas ejection portion. Due to the turbulent flow, the particles that are heated and form the gas diffuse to diffuse the gas itself. It becomes easy to release (propagate) heat to an object around the gas ejection part, and the heat of the gas is lowered.

Since the temperature of the gas is lowered in this way, in the inner tube and the airbag, the vicinity of the gas ejection portion is not easily affected by the heat of the gas.
The gas whose flow direction has been changed by collision with the vicinity of the fold line flows in a direction along the fold line. Both the gas and the gas flowing in the direction substantially perpendicular to the axis from the gas ejection part collide with the vicinity of the first joint, and change the flow direction in the direction along the axis. The gas flowing in one direction along the axis line passes through the gas discharge hole on the folding line, exits from the inner tube, and is supplied to one inflating portion of the airbag. In addition, the gas flowing to the other side in the direction along the axis passes through the open portion of the edge portion facing the fold line, exits the inner tube, and is supplied to the other inflatable portion of the airbag.

  Since the fold line is located near the gas ejection portion, a relatively high temperature gas collides with the vicinity of the fold line. However, in the vicinity of this fold line, there is no joint for joining both folds. Therefore, a portion near the fold line of the inner tube exhibits higher heat resistance than a joined portion by stitching or the like, and is not easily affected by the heat of the gas before the temperature is lowered.

  According to a second aspect of the present invention, in the first aspect of the present invention, the inflator includes a main body portion that extends in a direction along the axis and generates the gas, and the gas ejection portion is formed from the main body portion. Also, it is formed in a thin cylindrical shape and is provided at the end of the main body on the folding line side, and the gist is that the gas is ejected radially outward.

  According to the above configuration, in the inflator, gas is ejected radially outward from the gas ejection portion. A part of this gas flows toward the first joint and also flows toward the second joint. The latter gas collides with the vicinity of the second joint and changes the flow direction to a direction along the axis. At this time, the main body is located farther from the fold line than the gas ejection part, and is thicker than the gas ejection part. Therefore, the main body portion becomes a gas barrier whose flow direction is changed in the direction along the axis. Therefore, most of the gas whose flow direction has been changed flows to the side approaching the fold line.

  According to a third aspect of the present invention, there is provided the cylindrical retainer according to the second aspect, wherein the cylindrical retainer covers the inflator and is opened at least at an end portion on the gas ejection portion side in a direction along the axis. A window that is disposed in the inner tube and that corresponds to the gas ejection portion in the direction along the axis of the retainer and that faces the first joint portion in the circumferential direction of the retainer. The gist is that a portion is formed and a wall portion is formed at a location facing the second joint portion.

  According to the above configuration, when gas is ejected radially outward from the gas ejection portion of the inflator, a part of the gas flows toward the first joint portion and also flows toward the second joint portion. . The former gas flows out of the retainer through the window. The latter gas collides with the wall and changes the flow direction to a direction along the axis. At this time, the main body is located farther from the fold line than the gas ejection part, and is thicker than the gas ejection part. Therefore, the main body portion becomes a gas barrier whose flow direction is changed in the direction along the axis. This gas flows out of the retainer through the open end on the gas ejection side. Therefore, it is unlikely that the gas ejected radially outward from the gas ejection portion directly collides with the vicinity of the second joint portion of the inner tube.

  The invention according to claim 4 is characterized in that, in the invention according to any one of claims 1 to 3, a heat-resistant coating layer is formed on at least the inner surface of the inner tube. .

  According to said structure, the inner tube in which the heat resistant coating layer was formed exhibits heat resistance higher than that in which the coating layer is not formed. Therefore, the high-temperature gas ejected from the gas ejection part collides with each part in the inner tube, that is, a part near the fold line or a part near the first joint, but these parts receive from the heat of the gas. The effect can be further reduced by the coating layer.

  According to a fifth aspect of the present invention, in the invention according to any one of the first to fourth aspects, the fabric is constituted by a woven fabric, and the gas exhaust hole is formed around the gas exhaust hole in the fabric. The gist of the invention is that it is surrounded by an annular sewing portion provided by sewing.

  According to said structure, even if the thread | yarn which comprises an inner tube frays at the periphery of a gas exhaust hole (even if it unwinds), the phenomenon which the fray expands is blocked | prevented by the cyclic | annular sewing part around a gas exhaust hole. .

  A sixth aspect of the present invention is the invention according to any one of the first to fourth aspects, wherein the elongate fabrics are independent from each other and each have a plurality of gas discharge holes. And the plurality of woven fabrics are coupled together by an annular coupling portion around the gas discharge hole.

  According to the above configuration, in the plurality of woven fabrics constituting the fabric, even if the yarn frays at the peripheral edge of the gas discharge hole (even if it is unraveled), the phenomenon that the fray spreads around the gas discharge hole It is blocked by an annular joint that joins the sheets of fabric in an annular fashion.

  Moreover, the relative movement between the woven fabrics is restricted by the annular coupling portion in the vicinity of the gas discharge hole. Therefore, due to this relative movement, the position of the gas discharge hole is shifted between the woven fabrics, and the phenomenon that the gas discharge hole of the predetermined woven fabric is blocked by another woven fabric is less likely to occur.

  The invention described in claim 7 is the invention described in claim 6, wherein the annular coupling portion is formed by sewing the plurality of woven fabrics in an annular shape around the gas discharge hole. Is the gist.

  According to the above configuration, the plurality of woven fabrics are sewn in an annular shape around the gas discharge hole, that is, the two woven fabrics are joined together to form the annular coupling portion that couples the plurality of woven fabrics around the gas discharge hole. Can be formed easily.

  The invention according to an eighth aspect is the invention according to any one of the first to seventh aspects, wherein the airbag is inflated between an occupant seated on a vehicle seat and a body side portion of the vehicle. The pair of inflatable portions are provided at the upper and lower portions of the side airbag, and the inner tube has the fold line located on the lower side and the first joint portion on the front side. The gist of the present invention is that it is disposed in the airbag so as to be positioned, and that the inflator is inserted into the inner tube so that the axis extends in a substantially vertical direction.

  According to the above configuration, when an impact is applied to the vehicle from the side due to a side collision or the like, gas is ejected from the gas ejection portion of the inflator. The direction of the flow of the gas can be changed in the vertical direction in the process of passing through the inner tube. The gas whose direction is changed upward passes through the upper open end of the inner tube and is supplied to the inflating portion at the upper part of the airbag. The gas whose direction has been changed downward passes through the gas discharge hole on the lower side of the inner tube and is supplied to the inflating portion at the lower part of the airbag. The gas thus distributed and supplied to each inflatable portion causes each inflatable portion of the airbag to inflate and deploy between the vehicle body side portion and the occupant seated on the vehicle seat, and to the occupant through the body side portion. The impact from the side of the vehicle is reduced.

  According to the gas distribution structure of the airbag device of the present invention, the influence of heat can be suppressed by lowering the gas temperature while exhibiting the function of distributing the gas ejected from the gas ejection portion of the inflator.

BRIEF DESCRIPTION OF THE DRAWINGS It is a figure which shows one Embodiment which actualized this invention, and is a side view which shows the vehicle seat provided with the side airbag apparatus with a passenger | crew. The front sectional view which shows the positional relationship of a vehicle seat and a body side part with a passenger | crew and an airbag. Similarly, the plane sectional view which shows the positional relationship of a vehicle seat and a body side part with a passenger | crew and an airbag. The sectional side view which shows the internal structure of the airbag module by which the airbag was made into the deployment state with a vehicle seat and a passenger | crew. The top view which shows the state which looked at the inflator assembly from diagonally backward upper side with a side frame part, a nut, a side airbag, etc. FIG. The side view which shows the inner tube in a side airbag apparatus, and the inflator assembly inserted in this. The sectional side view which omits and shows the 2nd folding piece group of the inner tube in FIG. The side view which shows the fabric used for formation of an inner tube with an inflator assembly. The side view which shows the inner tube comprised with the fabric of 1 sheet with an inflator assembly. The side view which shows the inner tube with which the 2nd gas exhaust hole was provided with the inflator assembly.

Hereinafter, an embodiment in which a gas distribution structure of the present invention is applied to a side airbag device provided in a vehicle will be described with reference to FIGS.
In the following description, the forward direction of the vehicle will be described as the front (front of the vehicle), and the reverse direction of the vehicle will be described as the rear (rear of the vehicle). Further, in the following description, the vertical direction means the vertical direction of the vehicle, and the horizontal direction is the vehicle width direction of the vehicle and coincides with the horizontal direction when the vehicle moves forward.

  As shown in at least one of FIGS. 1 to 3, in the vehicle 10, a vehicle seat 12 is disposed in the vicinity of the vehicle side of the body side portion 11 (the right side in FIG. 2 and the upper side in FIG. 3). Here, the body side portion 11 refers to a member disposed on the side portion of the vehicle 10, and mainly includes a door, a pillar, and the like. For example, the body side part 11 corresponding to the front seat is a front door, a center pillar (B pillar), or the like. The body side portion 11 corresponding to the rear seat is a rear portion of a side door (rear door), a C pillar, a front portion of a tire house, a rear quarter, and the like.

  The vehicle seat 12 includes a seat cushion (seat portion) 13 and a seat back (backrest portion) 14 that stands up from the rear side of the seat cushion 13 and whose inclination angle is adjusted by an inclination adjustment mechanism (not shown). I have. A storage portion 15 is provided on the side of the seatback 14 outside the vehicle (see FIG. 3), and the airbag module AM that forms the main part of the side airbag device 17 is stored in the storage portion 15. The position of the storage portion 15 is set in the vicinity of the vehicle exterior of the occupant P seated on the vehicle seat 12. As shown in FIG. 4, the airbag module AM includes an inflator assembly 20, a side airbag 30, and an inner tube 40 as main components. 4 shows the airbag module AM in a state in which the side airbag 30 is deployed without being filled with the gas G in a state in which many portions (middle and lower portions) of the outer fabric portion 32 are broken. ing.

  Next, each of these structural members will be described. Here, in the present embodiment, when the airbag module AM and its constituent members are referred to as “vertical direction” and “front-rear direction”, the seat back 14 of the vehicle seat 12 is used as a reference. The direction in which the seat back 14 stands is the “vertical direction”, and the direction perpendicular to the front-rear direction of the vehicle 10 with respect to this direction is the “front-rear direction”. Usually, since the seat back 14 is used in an inclined state, the “vertical direction” is not strictly a vertical direction but is slightly inclined. Similarly, the “front-rear direction” is not strictly a horizontal direction but is slightly inclined.

<Inflator assembly 20>
As shown in at least one of FIGS. 5 and 7, the inflator assembly 20 includes an inflator 21 as a gas generator, and a retainer 22 that covers the inflator 21 from the outside. In the present embodiment, a type called a pyro type is employed as the inflator 21. The inflator 21 includes a main body portion 23 and a gas ejection portion 24 provided at a lower end portion thereof. The main body 23 has a substantially cylindrical shape elongated in the substantially vertical direction, and a gas generating agent (not shown) that generates the gas G for expansion is accommodated therein. A harness (not shown) serving as a wiring for applying a command signal to the inflator 21 is connected to the upper end of the main body 23. The gas ejection part 24 has a substantially cylindrical shape having a smaller diameter than the main body part 23 and is arranged on the same axis as the main body part 23. The gas ejection part 24 ejects the gas G generated in the main body part 23 radially outward from a large number of nozzle holes 25 provided on the outer peripheral surface thereof.

  As the inflator 21, a type (hybrid type) in which the partition of a high-pressure gas cylinder filled with a high-pressure gas is broken by an explosive or the like to eject gas is used instead of the pyro-type using the gas generating agent. Also good.

  On the other hand, the retainer 22 functions as a diffuser and has a function of fastening the inflator 21 together with the side airbag 30 and the inner tube 40 to the side frame portion 16 (see the two-dot chain line in FIG. 5) in the seat back 14. It is a member having. Most of the retainer 22 is formed in a substantially cylindrical shape elongated in a substantially vertical direction by bending a plate material such as a metal plate. The retainer 22 is locked to the main body portion 23 of the inflator 21 by, for example, caulking so that the diameter thereof is reduced. At least the lower end of the upper and lower ends of the retainer 22 is an open end 22A.

  In the retainer 22, a window portion 26 is opened above the open end 22 </ b> A and in the vicinity of the front side of the gas ejection portion 24 of the inflator 21. Therefore, most of the gas G ejected from the gas ejection part 24 can be ejected to the outside of the inflator 21 through the open end 22A or the window part 26, more specifically, substantially downward or substantially forward. Note that a portion different from the window portion 26 in the circumferential direction of the retainer 22 is a wall portion 27 that blocks the passage of the gas G. This location includes the vicinity of the rear side of the gas ejection portion 24. Here, if the length of the peripheral edge of the cross section orthogonal to the axis L of the inflator 21 is “perimeter” in the retainer 22, the peripheral length L 1 of the wall portion 27 is longer than the peripheral length L 2 of the window portion 26 in the retainer 22. It is set (see FIG. 5).

  A plurality of (two in this embodiment) bolts 28 are fixed to the retainer 22 as locking members for attaching the retainer 22 to the side frame portion 16. In other words, both bolts 28 are indirectly fixed to the inflator 21 via the retainer 22.

<Side airbag 30>
As shown in at least one of FIGS. 1 to 4, the side airbag 30 has a gas G from the inflator 21 when an impact is applied to the body side portion 11 from the outside of the vehicle 10 due to a side collision or the like. In a state where a part (rear part) of itself is left in the storage unit 15, it jumps out substantially forward from the storage unit 15. The side airbag 30 is for inflating and deploying in the gap G1 between the vehicle seat 12 and the body side portion 11, thereby restraining the occupant P and protecting it from the impact.

  The side airbag 30 is formed by folding a single fabric in two at the central portion, overlapping the same in the vehicle width direction, and joining the overlapped portions into a bag shape. Here, in order to distinguish the above-described two overlapped portions of the side airbag 30, the vehicle interior fabric portion 31 is referred to as the vehicle interior fabric portion 31 and the vehicle exterior fabric portion 32 is referred to as the vehicle exterior side. Shall. Both fabric parts 31, 32 are connected to each other at their rear edges.

As the cloth, a material having high strength and flexibility and can be easily folded, for example, a woven cloth formed using polyester yarn, polyamide yarn or the like is suitable.
The above-described coupling between the fabric parts 31 and 32 on the vehicle inner side and the vehicle outer side is performed at a peripheral coupling part 33 provided along the peripheral edge thereof. In the present embodiment, the peripheral edge coupling portion 33 is formed by sewing (sewing with a sewing thread) the peripheral edge portions of both the fabric portions 31 and 32. The peripheral edge coupling portion 33 by the sewing thread is distinguished from a normal broken line (hidden line) by being represented by a thick broken line (see the upper part of FIG. 4). Moreover, when showing the cross section of the periphery coupling | bond part 33 by a sewing thread, ie, in order to show the internal structure of both the fabric parts 31 and 32, when making the surface which passes along the periphery coupling | bond part 33 into a cross section, the same periphery coupling | bond part 33 Is expressed by a line type (a type of broken line) in which points are arranged at regular intervals (see the middle and lower part of FIG. 4). These expression modes are the same for the first joint portion 53 and the second joint portion 55 of the inner tube 40 described later.

  Note that the side airbag 30 may be formed by overlapping a pair of fabrics having the same shape in the vehicle width direction and joining the peripheral portions thereof. Further, the peripheral edge coupling portion 33 may be formed by means different from the sewing using the sewing thread, for example, bonding using an adhesive. The same applies to a first joint portion 53, a second joint portion 55, and an annular joint portion 61 of the inner tube 40 described later.

  The side airbag 30 includes a head protection inflating portion 34, a waist protection inflating portion 35, an intermediate inflating portion 36, and a non-inflating portion 37. The head protection inflating portion 34 is a portion that inflates near the side of the head PH of the occupant P and protects the head PH from impact. The waist protection inflating part 35 is inflated in the vicinity of the side of the waist part PP of the occupant P, and protects the waist part PP from impact. The intermediate expansion portion 36 is provided with the inner tube 40 and the inflator assembly 20, and guides the gas G ejected from the inflator 21 and distributed by the inner tube 40 to the head protection expansion portion 34 and the waist protection expansion portion 35. It is a place. The intermediate inflating part 36 extends substantially in the vertical direction and is connected to the head protecting inflating part 34 and the waist protecting inflating part 35. The non-expandable portion 37 is a portion where the expansion by the gas G is not performed, and is surrounded by the head protection expansion portion 34, the waist protection expansion portion 35, and the intermediate expansion portion 36. The non-inflatable part 37 is constituted by a part of the vehicle interior fabric part 31 and a part of the vehicle exterior fabric part 32.

<Inner tube 40>
The inner tube 40 directs the gas G ejected from the gas ejection part 24 of the inflator 21 to a direction along the axis L of the inflator 21 and distributes the gas G to the head protection expansion part 34 and the waist protection expansion part 35. It is used as a main purpose and is disposed in the intermediate expansion portion 36.

  As shown in at least one of FIGS. 6 to 8, the inner tube 40 is formed using a long fabric 41. The fabric 41 is composed of a plurality of (three in the present embodiment) woven fabrics 42 having the same shape. As each woven fabric 42, like the side airbag 30, a fabric that has high strength and is flexible and can be folded is used. A heat resistant coating layer 43 made of an elastomer such as chloroprene or silicone is formed on both the inner and outer surfaces of each woven fabric 42. Such a woven fabric 42 is generally called a “coating fabric”.

  The long woven fabrics 42 are overlapped with each other in the thickness direction. These woven fabrics 42 overlapped and layered are folded in two along a fold line 45 perpendicular to the longitudinal direction at the center in the longitudinal direction of each woven fabric 42. Thus, for each woven fabric 42, a pair of folded pieces having the same shape is formed. In order to distinguish the folded pieces for each woven fabric 42 from each other, the one located on the inner side of the vehicle is referred to as a first folded piece 46, and the one located on the outer side of the vehicle is referred to as a second folded piece 47. The first fold piece 46 and the second fold piece 47 for each woven fabric 42 are connected to each other at the fold line 45 portion without using a joining means such as stitching.

  By bending the woven fabric 42, the inner tube 40 has a first folded piece group 51 (see FIG. 7), which is a group of first folded pieces 46 for each woven fabric 42, and a second folded piece for each woven fabric 42. The second folded piece group 52 (see FIG. 6), which is a group of 47, is a multilayered structure (six layers) overlapped.

  The first fold piece group 51 and the second fold piece group 52 are joined to each other by a plurality (three in the present embodiment) of first joint portions 53. Each first joint portion 53 is provided along one (front) edge portion 54 orthogonal to the fold line 45 in the first fold piece group 51 and the second fold piece group 52. In this embodiment, the 1st junction part 53 is formed by co-sewing the 1st fold piece group 51 and the 2nd fold piece group 52 with the sewing thread along the edge part 54 linearly.

  The first folded piece group 51 and the second folded piece group 52 are joined to each other by a plurality (three in the present embodiment) of second joined portions 55. Each second joint portion 55 is provided along the other (rear) edge portion 56 orthogonal to the fold line 45 in the first fold piece group 51 and the second fold piece group 52. In the present embodiment, the second joint 55 is formed by co-sewing the first fold piece group 51 and the second fold piece group 52 along the edge 56 in a straight line with a sewing thread.

The interval between the first joint portion 53 and the second joint portion 55 is set so as to have a cylindrical shape having substantially the same diameter as that of the intermediate expansion portion 36 in the expanded state when the inner tube 40 is expanded.
The first fold piece group 51 and the second fold piece group 52 are not joined to each other at the edge portion 57 facing the fold line 45 but are opened. This open portion is herein referred to as the upper open end 49. In the upper open end 49, the adjacent first folded pieces 46 are not joined to each other in the direction along the edge 57, and the adjacent second folded pieces 47 are not joined to each other in the same direction.

  The first folded piece group 51 and the second folded piece group 52 are not joined to each other in the direction along the folded line 45 in the vicinity of the folded line 45. In the vicinity of the fold line 45, the adjacent first fold pieces 46 are not joined to each other in the direction along the fold line 45, and the adjacent second fold pieces 47 are not joined to each other. .

  A gas discharge hole 59 is provided at a position near the first joint portion 53 on the fold line 45 of each woven fabric 42 so as to straddle the first fold piece 46 and the second fold piece 47. In the inner tube 40, the internal space (the space between the first folded piece group 51 and the second folded piece group 52) and the outside are communicated with each other by a gas discharge hole 59 for each woven fabric 42.

  The plurality of woven fabrics 42 are coupled by a common annular coupling portion 61 provided around each gas discharge hole 59. The annular coupling portion 61 is formed by sewing (sewing together) a plurality of woven fabrics 42 in a ring shape around each gas discharge hole 59. The annular coupling portion 61 does not couple the first folded piece group 51 and the second folded piece group 52.

  Furthermore, bolts having a slightly larger diameter than the bolts 28 of the retainer 22 are inserted into two locations along the longitudinal direction of the second joint portion 55 of the first folded piece group 51 near the second joint portion 55. A hole 62 is formed.

In FIG. 5, illustration of the inner tube 40 is omitted.
The inner tube 40 is configured as described above. And many parts of the inflator assembly 20 are located in the upper open end of the inner tube 40 so that the gas ejection part 24 is located at a location that is biased toward the second joint 55 side and the folding line 45 side of the inner tube 40. 49 is inserted through the inner tube 40. The upper end portion of the inflator assembly 20 is located above the upper open end 49 and is exposed from the inner tube 40.

  Further, the two bolts 28 of the retainer 22 are respectively inserted into the corresponding bolt insertion holes 62 of the first folded piece group 51 and the vehicle interior fabric portion 31 of the side airbag 30. By such insertion, the inflator assembly 20 and the inner tube 40 are locked in a state of being positioned with respect to the side airbag 30. Thus, a gas distribution structure is configured by the combination of the inflator assembly 20 and the inner tube 40 that are locked to the side airbag 30.

  By the way, in the airbag module AM having the side airbag 30, the inflator assembly 20 and the inner tube 40 as main components, the deployed side airbag 30 (see FIG. 4) is folded together with the inner tube 40. Thus, the storage form is compact. This is because the airbag module AM can be easily stored in the storage unit 15 having a limited size in the seat back 14.

  The airbag module AM in the above-described storage form has the storage portion 15 of the seat back 14 with the inflator assembly 20 and the inner tube 40 positioned on the rear side and most of the side airbags 30 positioned on the front side. Is housed in. As described above, the bolt 28 extending from the retainer 22 and inserted into the inner tube 40 and the side airbag 30 is inserted into the side frame portion 16 and tightened by the nut 29 (see FIG. 5). By this tightening, the inflator assembly 20 and the inner tube 40 are fixed to the side frame portion 16 together with the side airbag 30. The inflator assembly 20 may be fixed to the vehicle 10 (side frame portion 16) by a member different from the bolt 28 and the nut 29 described above.

  As shown in FIG. 1, the side airbag device 17 includes an impact sensor 71 and a control device 72 in addition to the airbag module AM described above. The impact sensor 71 is composed of an acceleration sensor or the like, and is provided on the body side portion 11 (see FIGS. 2 and 3) of the vehicle 10, and detects an impact applied to the body side portion 11 from the side. The control device 72 controls the operation of the inflator 21 based on the detection signal of the impact sensor 71.

  As described above, the side airbag device 17 having the gas distribution structure is configured. In the side airbag device 17, an impact of a predetermined value or more is applied to the body side portion 11 of the vehicle 10 due to a side collision or the like, and when this is detected by the impact sensor 71, the control device 72 is based on the detection signal. A command signal for operating this is output to the inflator 21. In response to this command signal, in the main body 23, the gas generating agent generates a high-temperature and high-pressure gas G, which is ejected from the plurality of nozzle holes 25 of the gas ejection section 24 in substantially all directions radially outward ( (See FIG. 5). Here, as described above, since the circumferential length L1 of the wall portion 27 is longer than the circumferential length L2 of the window portion 26, the amount of gas G toward the wall portion 27 is greater than the amount of gas G toward the window portion 26. There are many.

  As shown in FIG. 7, in the cylindrical retainer 22 covered on the inflator 21, the window portion 26 and the lower open end 22 </ b> A mainly allow passage of the gas G from the gas ejection portion 24, and the wall The part 27 blocks the passage of the gas G.

  In the present embodiment, since the window portion 26 is provided only substantially at the front portion of the retainer 22, the gas G ejected substantially forward from a part of the gas ejection portions 24 passes through the window portion 26. The amount of the gas G is smaller than the amount of the gas G that collides with the wall portion 27 because of the circumference relationship (L1> L2). The gas G that has passed through the window portion 26 collides with the vicinity of the first joint portion 53 in the inner tube 40 and changes the flow direction in a direction along the first joint portion 53 (substantially up and down direction).

  Further, the gas G ejected from the gas ejection part 24 in a direction other than substantially forward, such as substantially rearward, collides with the wall part 27. The amount of the gas G that collides is larger than the amount of the gas G that passes through the window portion 26 from the relationship of the circumference (L1> L2). Further, the gap between the wall 27 and the inflator 21 can be a gas G passage. Therefore, the gas G ejected from the gas ejection part 24 substantially rearward and colliding with the wall part 27 tends to change its flow direction into two directions (substantially upward and substantially downward) along the axis L of the inflator 21.

  At this time, the main body portion 23 is located on the side far from the fold line 45 (substantially upper side) with respect to the gas ejection portion 24 and is thicker (has a larger diameter) than the gas ejection portion 24. The gap between the main body part 23 and the wall part 27 is smaller than the gap between the gas ejection part 24 and the wall part 27. The main body 23 and the gap serve as a barrier for the gas G whose flow direction is changed in the direction along the axis L. Therefore, the gas G hardly enters the narrow gap between the main body portion 23 and the wall portion 27, and most of the gas G flows substantially downward along the axis L.

  Therefore, the gas G whose direction of flow has been changed by hitting the wall portion 27 as described above passes through the lower open end 22A of the retainer 22 and flows substantially downward. Therefore, it is unlikely that the gas G ejected radially outward from the gas ejection portion 24 directly collides with the vicinity of the second joint portion 55 of the inner tube 40.

  Further, from the relationship between the circumferences (L1> L2), the amount of the gas G that flows substantially downward through the open end 22A is larger than the amount of the gas G that flows substantially forward through the window portion 26. The gas G flowing through the open end 22A substantially downwardly collides with the vicinity of the folding line 45 of the inner tube 40. The energy of the gas G is consumed due to the change in the flow direction of the gas G accompanying the collision, and the temperature of the gas G is lowered accordingly.

  Further, in the inner tube 40, the flow direction of the gas G is changed in the vicinity of the gas ejection part 24 (a part near the folding line 45 or a part near the front of the gas ejection part 24), so that some turbulence flows. Occurs. Due to this turbulent flow, the particles that are heated and form the gas G diffuse, so that the gas G itself also diffuses. Heat is easily released (propagated) to the objects (inner tube 40, side airbag 30 and the like) around the gas ejection part 24, and the heat of the gas G is lowered.

  Since the temperature of the gas G is lowered in this way, in the inner tube 40 and the side airbag 30, the vicinity of the gas ejection portion 24 (region Z <b> 1 indicated by a halftone dot in FIG. 7) is affected by the heat of the gas G. It becomes difficult.

  The gas G whose flow direction has been changed due to a collision with the vicinity of the fold line 45 flows substantially forward along the fold line 45. The gas G and the gas G flowing substantially forward from the gas ejection part 24 through the window part 26 collide with the vicinity of the first joint part 53 and are along the axis L (substantially up and down direction). Change the flow direction. The gas G flowing in one direction (substantially downward) in the direction along the axis L is supplied to the waist protection expansion portion 35 below the inner tube 40 through the gas discharge hole 59. Further, the gas G flowing to the other side (substantially upward) in the direction along the axis L is supplied to the head protection inflating portion 34 above the inner tube 40 through the upper open end 49.

  In addition, since the folding line 45 is near the gas ejection part 24, a relatively high temperature gas G collides with the vicinity of the folding line 45. However, in the vicinity of the fold line 45, there is no joint portion for joining the first fold piece 46 and the second fold piece 47. Therefore, a portion near the fold line 45 of the inner tube 40 exhibits higher heat resistance than a joined portion by stitching or the like, and is hardly affected by the heat of the gas G before the temperature decreases.

  Moreover, the inner tube 40 in which the heat resistant coating layer 43 is formed exhibits higher heat resistance than that in which the coating layer 43 is not formed. Therefore, the high-temperature gas G ejected from the gas ejection part 24 collides with each part in the inner tube 40, that is, a part near the fold line 45, a part near the first joint part 53, and the like as described above. The entire inner tube 40 including the impacted portion is protected from heat by the coating layer 43.

  As described above, the gas G ejected from the inflator 21 is supplied to the waist protection inflating portion 35 through each gas discharge hole 59 of the inner tube 40 and passes through the upper open end 49 of the inner tube 40. It is supplied to the head protection expansion part 34. By these supply, the folded inner tube 40 and the side airbag 30 are both inflated while eliminating (deploying) the folded state.

  Then, the side airbag 30 jumps out from the seat back 14 in a state where a part (the vicinity of the inflator assembly 20) is left in the storage portion 15 of the seat back 14. Thereafter, the gas G that is supplied causes the head protection inflating portion 34 to inflate and deploy in the vicinity of the side of the head PH of the occupant P to protect the head PH from impact caused by a side collision, and the waist protection inflating portion 35 Inflate and deploy in the vicinity of the lateral side of the P waist part PP, and protect the waist part PP from impacts caused by side impacts.

According to the embodiment described in detail above, the following effects can be obtained.
(1) A first joint portion 53 in which a first fold piece 46 and a second fold piece 47 formed by bending the fabric 41 along a fold line 45 are provided along edges 54 and 56 perpendicular to the fold line 45. The inner tube 40 is formed by being joined to each other by the second joining portion 55 and having the edge portion 57 facing the folding line 45 opened. The inflator assembly 20 is inserted into the inner tube 40 so that the gas ejection portion 24 is located at a location that is biased toward the second joint portion 55 side and the folding line 45 side of the inner tube 40. And the gas exhaust hole 59 is provided in the location near the 1st junction part 53 on the folding line 45 (FIG.6 and FIG.7).

  Therefore, the gas G ejected from the gas ejection part 24 to the inner tube 40 is distributed and supplied to the head protection expansion part 34 through the upper open end 49 and distributed to the waist protection expansion part 35 through the gas discharge hole 59. Can be supplied. Further, the influence of heat can be suppressed by lowering the temperature of the gas G by changing the flow direction due to a collision with each part of the inner tube 40 or by diffusion due to turbulent flow.

  Moreover, since the vicinity part of the gas ejection part 24 in the inner tube 40 is bend | folded along the fold line 45, the heat resistance of the vicinity part can be improved, and it can make it less susceptible to the heat | fever of the gas G.

  (2) As the inflator 21, a main body 23 that extends in the direction along the axis L to generate gas G, a columnar shape that is thinner than the main body 23, and is provided at the lower end of the main body 23, has a diameter. What is provided with the gas ejection part 24 which ejects the gas G to the direction outward (FIG. 7) is used.

  For this reason, a part of the gas G ejected from the gas ejection part 24 can be caused to flow along the axis L to the fold line 45 side (substantially lower side), and the effect of the above (1) can be ensured. It can be.

  (3) A cylindrical retainer 22 that covers the inflator 21 that extends substantially in the vertical direction and that is open at least at the lower end is disposed in the inner tube 40. A window portion 26 is formed in a front portion of the retainer 22 in the circumferential direction of the retainer 22 and a wall portion 27 is formed in other portions (including the rear portion). (FIG. 7).

  For this reason, a part of the gas G ejected from the gas ejection part 24 can be caused to flow substantially forward through the window part 26. In addition, a part of the gas G ejected from the gas ejection part 24 is caused to flow toward the folding line 45 along the axis L without directly colliding with the vicinity of the second joint part 55 of the inner tube 40. Can do.

  (4) As the plurality of woven fabrics 42 constituting the fabric 41 of the inner tube 40, one having coating layers 43 formed on both inner and outer surfaces is used (FIG. 6). Therefore, the influence which each part in the inner tube 40 receives from the heat | fever of the gas G can be made still smaller.

  (5) A plurality of woven fabrics 42 are joined around each gas discharge hole 59 by an annular coupling portion 61 (FIG. 7). Therefore, even if the yarn of each woven fabric 42 is frayed at the peripheral edge of the gas discharge hole 59, it is possible to prevent the fray from spreading by the annular coupling portion 61.

  Further, the relative movement between the woven fabrics 42 in the vicinity of the gas discharge hole 59 can be restricted by the annular coupling portion 61. Therefore, it is possible to suppress a phenomenon in which the gas discharge hole 59 is displaced between the woven fabrics 42 due to relative movement, and the gas discharge holes 59 of the predetermined woven fabric 42 are blocked by the other woven fabrics 42.

  (6) The annular coupling portion 61 is formed by sewing (sewing together) a plurality of woven fabrics 42 around the gas discharge hole 59 in an annular shape (FIG. 7). Therefore, the annular coupling portion 61 of the above (5) can be easily formed.

  (7) The distribution amount of the gas G to the waist protection expansion part 35 and the head protection expansion part 34 by the inner tube 40 can be easily adjusted by changing the hole diameter of the gas discharge hole 59. As the hole diameter of the gas discharge hole 59 is increased, the amount of the gas G supplied to the waist protection expansion part 35 through the gas discharge hole 59 can be increased.

Note that the present invention can be embodied in another embodiment described below.
<About side airbag 30>
The non-inflatable portion 37 may be formed by only one of the fabric portions 31 and 32.

  In FIG. 4, a portion surrounded by the head protection expansion part 34, the waist protection expansion part 35, and the intermediate expansion part 36 may be configured by a space, and this may be a non-expansion part 37. In this case, the fabric portions 31 and 32 do not exist in the non-inflatable portion 37. Therefore, when the side airbag 30 is folded into a storage form, the non-inflatable portion 37 is constituted by the two fabric portions 31 and 32 as well as the non-inflatable portion 37 is changed to the inflatable portion. As a result, the volume of the side airbag 30 becomes smaller. For this reason, there exists a merit which becomes easy to accommodate the airbag module AM in the accommodating part 15. FIG.

The head protection inflating part 34 and the waist protection inflating part 35 may be adjacent to each other via a partition part such as a tether or a seam provided in the side airbag 30.
The tether is composed of a belt-like cloth that is disposed between the fabric portions 31 and 32 of the side airbag 30 and is joined to the corresponding fabric portions 31 and 32 at its side edge portions. Are used in a state of being connected at a predetermined interval.

  The seam is a joint portion by a sewing thread or the like, and is used when the two fabric portions 31 and 32 are connected to each other in a state of being in contact with each other by stitching the both fabric portions 31 and 32 with a sewing thread.

<Inner tube 40>
-As shown in FIG. 9, you may use as the fabric 41 what was formed with the one woven fabric 42 which makes long shape. Also in this case, as in the above-described embodiment, if some treatment is not performed on the periphery of the gas discharge hole 59, the yarn of the woven fabric 42 may be loosened (unraveled) at the periphery of the gas discharge hole 59. Therefore, it is effective to surround the gas discharge hole 59 in the fabric 41 with an annular sewing portion 66 provided by sewing around the gas discharge hole 59. In this way, even if the yarn constituting the inner tube 40 is frayed (unwound) at the periphery of the gas discharge hole 59, the phenomenon that the fray spreads can be prevented by the sewing portion 66.

-At least one of the 1st junction part 53 and the 2nd junction part 55 may be formed by adhere | attaching the adjacent woven fabric 42 with an adhesive agent.
The folding line 45 is not limited to being orthogonal to the longitudinal direction of the fabric 41, and may be one that intersects obliquely.

  -The fold line 45 may be set in the location deviated from the center part of the fabric 41 in the longitudinal direction. In this case, the first fold piece 46 and the second fold piece 47 formed by bending the fabric 41 along the fold line 45 have different lengths.

  -You may provide at least one of the 1st junction part 53 and the 2nd junction part 55 different from the said embodiment. FIG. 9 shows an example in which two first joint portions 53 and two second joint portions 55 are provided.

<About coating layer 43>
-The part exposed directly to the gas G in the inner tube 40 is an inner surface. Therefore, when the coating layer 43 is formed, it is important that at least the inner surface of the inner tube 40 is a surface on which the coating layer 43 is to be formed. About locations other than the said inner surface of the inner tube 40, according to the grade of the heat damage by the gas G, it is possible to omit the coating layer 43. FIG.

For example, when the fabric 41 of the inner tube 40 is constituted by a single woven fabric 42 (see FIG. 9), the coating layer 43 on the outer surface of the woven fabric 42 may be omitted.
When the fabric 41 of the inner tube 40 is composed of a plurality of woven fabrics 42 (see FIG. 7), a coating layer 43 is formed on the inner surface of the woven fabric 42 located on the innermost side, and the woven fabric 42 is formed. The coating layer 43 may be omitted with respect to the outer surface and other inner and outer surfaces of the woven fabric 42.

As the woven fabric 42 of the fabric 41 of the inner tube 40, a so-called non-coated fabric in which the coating layer 43 is not formed on either the inner surface or the outer surface may be used.
<About the inflator assembly 20>
The inflator assembly 20 may be one in which the inflator 21 and the retainer 22 are integrated.

The inflator assembly 20 may be one in which the bolts 28 are directly fixed to the inflator 21 without using the retainer 22.
Of the both end portions of the retainer 22, the end portion (upper end portion) opposite to the side where the gas ejection portion 24 is provided in the length direction of the inflator 21 may be closed.

  -The inflator assembly 20 should just be the thing in which the gas ejection part 24 of the inflator 21 is arrange | positioned in the inner tube 40. FIG. Therefore, the inflator assembly 20 may be a part (upper end portion) of the inflator assembly 20 exposed from the inner tube 40 as in the above-described embodiment. Although not illustrated, the entire inflator assembly 20 is disposed in the inner tube 40. It may be a thing.

<About the storage unit 15 of the airbag module AM>
-The storage part 15 of the airbag module AM may be provided in the body side part 11 instead of the seat back 14 of the vehicle seat 12.

<Others>
-This invention is applicable also to the side airbag apparatus 17 provided with the airbag by which a pair of expansion part was provided in the front-back direction. In this case, examples of the part of the occupant to be protected by the inflatable part include the front part and the rear part of the upper body. Further, the long inflator 21 is disposed in a substantially horizontal state.

  In the case of the side airbag device 17 including an airbag provided with a pair of inflating parts in the vertical direction, the occupant P that is to be protected by the inflating parts includes the waist PP, the abdomen, the chest, the shoulders, the head Part PH and the like. Moreover, these parts may be adjacent to each other or may be separated from each other.

  The airbag to which the present invention is applied has inflatable portions at least at two locations along the axis L of the inflator 21, but has a third inflatable portion between the two inflatable portions. May be.

  As said side airbag 30, what has a 3rd expansion | swelling part between the waist protection expansion | swelling part 35 and the head protection expansion | swelling part 34 of the said embodiment is mentioned, for example. In this case, as shown in FIGS. 9 and 10, in order to supply the gas G ejected from the gas ejection portion 24 of the inflator 21 and supplied to the inner tube 40 to the third expansion portion, A second gas discharge hole 65 may be newly provided in the vicinity of the one joint portion 53.

  FIG. 9 shows an example in which the second gas discharge hole 65 is provided at a position slightly separated from the first joint portion 53 in the second folded piece 47. The second gas discharge hole 65 may be provided in the first folded piece 46 instead of or in addition to the second folded piece 47.

  FIG. 10 shows an example in which the second gas discharge hole 65 is provided on the first joint portion 53. In this case, the folded pieces 46 and 47 are not joined by the first joining portion 53 at the location where the second gas discharge hole 65 is provided. A location where the first joint portion 53 is divided is provided, which is referred to as a second gas discharge hole 65.

In any of the above examples, the second gas discharge hole 65 is provided at a location that is biased toward the upper open end 49 side from the gas ejection portion 24 in the direction along the axis L.
The present invention is not limited to the side airbag device 17, but is an airbag between another airbag device, for example, the head PH of the occupant P seated on the vehicle seat 12 and the side portion of the vehicle 10 in the vehicle interior. It can also be applied to a head protecting airbag device (curtain shield airbag device) that protects the head PH by inflating the head. In this case, it is assumed that the inflator 21 is built in the airbag.

  DESCRIPTION OF SYMBOLS 10 ... Vehicle, 11 ... Body side part, 12 ... Vehicle seat, 17 ... Side airbag apparatus, 21 ... Inflator, 22 ... Retainer, 23 ... Main part, 24 ... Gas ejection part, 26 ... Window part, 27 ... Wall , 30 ... side airbag (airbag), 34 ... head protection inflating part (inflation part), 35 ... waist protection inflating part (inflation part), 40 ... inner tube, 41 ... fabric, 42 ... woven cloth, 43 ... coating layer, 45 ... fold line, 46 ... first fold (fold), 47 ... second fold (fold), 53 ... first joint, 54 ... one edge, 55 ... second joint 56, the other edge, 57, an edge facing the fold line, 59, a gas discharge hole, 61, an annular coupling part, 66, a sewing part, G, gas, L, an inflator axis, P, an occupant.

Claims (8)

Applied to an airbag device comprising a long inflator and an airbag having an inflating portion at two different locations along at least the axis of the inflator, the gas ejected from the gas ejection portion of the inflator A gas distribution structure of an airbag device that distributes to each inflatable portion by directing in a direction along the axis by a tube;
A pair of folded pieces are formed by bending a long fabric along a fold line intersecting the longitudinal direction thereof,
The folds are joined together by a first joint provided along one edge that intersects the fold line of the fabric, and along the other edge that intersects the fold line of the fabric. Are joined together by the second joint provided to form the inner tube with an open edge facing the fold line,
The inflator is inserted into the inner tube so that the gas jetting part is located at a location biased toward the second joint part side and the fold line side of the inner tube, and further, the first on the fold line is inserted. A gas distribution structure for an airbag apparatus, wherein a gas discharge hole is provided at a location near the joint. The inflator includes a body portion that extends in a direction along the axis and generates the gas,
The gas ejection part is formed in a columnar shape that is thinner than the main body part, is provided at an end of the main body part on the folding line side, and ejects the gas radially outward. 2. A gas distribution structure for an air bag device according to 1. A cylindrical retainer that covers the inflator and that is open at least on the gas ejection part side in the direction along the axis is disposed in the inner tube,
A window portion is formed at a location corresponding to the gas ejection portion in the direction along the axis of the retainer and facing the first joint portion in the circumferential direction of the retainer, and the second joint portion. The gas distribution structure of the airbag apparatus according to claim 2, wherein a wall portion is formed at a location opposite to. The gas distribution structure of an airbag apparatus according to any one of claims 1 to 3, wherein a heat-resistant coating layer is formed on at least an inner surface of the inner tube. The fabric is made of woven fabric,
The gas distribution structure of an airbag device according to any one of claims 1 to 4, wherein the gas discharge hole is surrounded by an annular stitching portion provided by sewing around the gas discharge hole in the fabric. . The elongate fabric is configured by overlapping a plurality of woven fabrics that are independent of each other and each have the gas discharge holes,
The gas distribution structure of an airbag device according to any one of claims 1 to 4, wherein the plurality of woven fabrics are coupled by an annular coupling portion around the gas discharge hole. The gas distribution structure of an airbag device according to claim 6, wherein the annular coupling portion is formed by sewing the plurality of woven fabrics in an annular shape around the gas discharge hole. The airbag is a side airbag that is inflated between an occupant seated in a vehicle seat and a body side portion of the vehicle,
The pair of inflatable portions are provided at the upper and lower portions of the side airbag,
The inner tube is disposed in the airbag such that the fold line is located on the lower side and the first joint is located on the front side,
Furthermore, the said inflator is a gas distribution structure of the airbag apparatus as described in any one of Claims 1-7 inserted in the said inner tube so that the said axis line may extend in a substantially up-down direction.

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