JP5176923B2 - Side airbag device - Google Patents

Description

  The present invention relates to a side airbag device that protects an occupant from an impact when the vehicle is subjected to an impact from the side.

  A side airbag device including an inflator and an airbag is effective as a device for protecting an occupant from a side impact applied to the vehicle due to a side collision or the like. This side airbag device includes an inflator that ejects an inflation gas in response to an impact from the side of the vehicle, and an airbag that encloses the inflator in its rear part. The airbag and the inflator are stored for storage when the airbag is folded, and stored in a storage portion in the seat back of the vehicle seat. According to this side airbag device, when an impact is applied to the body side portion of the vehicle from the side, the inflator jets the inflation gas into the airbag. The airbag is inflated and deployed from the seat back toward the front of the vehicle in a narrow space between the occupant seated on the vehicle seat and the body side part while eliminating the folded state by the jetted inflation gas, Mitigates the impact from the side transmitted to the occupant through the body side.

  In addition to the above basic configuration, for example, Patent Document 1 discloses a side airbag device in which an inner tube (flexible / inflatable portion) that covers an inflator is further provided at a rear portion in an airbag. The airbag is constituted by a single inflating part. The inner tube has an elongated tube shape in the vertical direction, and openings are provided at three locations (upper end portion, central portion, and lower end portion). According to the side airbag device, the inflation gas ejected from the inflator receives the rectifying action of the inner tube. The inflation gas exiting the upper opening of the inner tube flows upward (upper part in the airbag). The inflation gas that has exited the central opening of the inner tube flows toward the front (the front part in the airbag). The inflation gas exiting the lower opening of the inner tube flows downward (lower part in the airbag).

  Here, it is generally known that the waist and shoulders are superior to the chest with respect to the impact resistance of the human body side. For this reason, in the case of a side airbag device that protects an occupant over a wide area extending from the waist to the shoulder, it is desirable to protect the chest softer than the waist and shoulder with an airbag that is inflated and deployed.

  In this regard, in the side airbag device described in Patent Document 1 described above, the flow direction of the inflation gas ejected from the inflator is directed to the three directions of the upper, the front, and the lower by the inner tube with respect to a single inflatable portion. It only changes. In the side airbag device, the pressure (internal pressure) in the inflatable portion due to the inflating gas varies depending on the side portion of the occupant, that is, the internal pressure at the location corresponding to the chest in the inflatable portion is reduced, and the waist and It is difficult to increase the internal pressure at the location corresponding to the shoulder.

Regarding this, for example, Patent Document 2 describes a side airbag device in which an airbag is partitioned into a waist protection inflating portion, a chest protection inflating portion, and a shoulder protecting inflating portion by a seam having a substantially U-shaped side surface. Has been. Openings are provided in the upper and lower portions of the inner tube that covers the inflator. In this side airbag device, the inflation gas ejected from the inflator is supplied from the lower opening and the upper opening of the inner tube to the waist protection inflating part and the shoulder protecting inflating part at substantially the same time. Both protective inflating parts begin to expand at approximately the same time. The inflation gas supplied to both protective inflating parts bypasses the seam and is supplied to the chest protective inflating part, and the protective inflating part expands behind the protective inflating parts on the waist and shoulders. Start. Then, the inflation gas provided for the inflation of the chest protection inflatable portion is discharged to the outside of the airbag from the exhaust port provided in the chest protection inflatable portion. For this reason, it is possible to inflate the chest protection inflating portion with a lower internal pressure than the waist protection inflating portion and the shoulder protection inflating portion, thereby protecting the occupant's chest softer than the waist and shoulder.
JP 2005-507820 A JP 2005-22473 A

  However, as described above, the side airbag device described in Patent Document 2 supplies the inflation gas from the inflator to the waist protection inflating portion and the shoulder protection inflating portion first, and then the chest protection. The structure which supplies to the expansion part for an operation is taken. Therefore, the expansion and deployment of the chest protection inflating portion is slower than the inflating and deploying of both the waist and shoulder protection inflating portions. Therefore, this side airbag device has room for improvement in terms of airbag deployment performance.

  The present invention has been made in view of such circumstances, and its purpose is to inflate and deploy each inflatable part with an internal pressure corresponding to the impact resistance of the occupant's part, while the specific inflating part has other inflated parts. An object of the present invention is to provide a side airbag device capable of suppressing the inflation and deployment extremely late than the inflatable portion and improving the deployment performance of the airbag.

In order to achieve the above-mentioned object, the invention according to claim 1 is directed to an occupant seated on a vehicle seat with an airbag that is enclosed in an inflator and folded to be stored. The airbag is stored in the vicinity of the outside of the vehicle and inflated toward the front of the vehicle between the body side portion of the vehicle and the vehicle seat by the inflation gas ejected from the inflator in response to an impact from the side of the vehicle. In the side airbag device to be deployed, the airbag is divided into a central inflating portion, an upper inflating portion above the central inflating portion, and a lower inflating portion below the central inflating portion. cage, the said central expansion portion, the inner bag is provided for containing the inflator, vehicle-side fabric constituting the inner bag is coupled to the vehicle interior side fabric constituting the airbag In addition, the outer fabric constituting the inner bag is coupled to the outer fabric constituting the airbag, and a partition portion between the central inflating portion and the upper inflating portion, and the central inflating portion and the lower inflating portion. Either one of the partition portions is partitioned by coupling, and the other is partitioned by stitching, and the portions partitioned by the stitching are the inner fabric and the outer fabric of the inner bag, and the inner fabric of the airbag. And the outer fabric of the vehicle are co-sewn in the vehicle front-rear direction, and the inner bag communicates with the upper inflating portion through an upper opening provided on the upper side of the inner bag. It communicates with the lower inflating part through a lower opening provided on the lower side of the bag, and further through the intermediate part opening provided in the inner bag. In the state where the airbag is inflated and deployed, the inner bag has a front end behind the front end of the central inflating portion and a front end of the seat back in the vehicle seat. Also, the gist is that they are arranged so as to be positioned forward.

  According to the above configuration, when an impact is applied to the vehicle from the side, the inflation gas is ejected from the inflator. The inflation gas is first supplied to the inner bag, and the inner bag is inflated. The outer central inflatable portion is inflated by the inflating inner bag. Further, the inflation gas in the inner bag flows from the upper opening into the upper inflation part, from the lower opening to the lower inflation part, and from the middle opening to the central inflation part. The expansion gas flowing in this way causes each of the upper expansion portion, the lower expansion portion, and the central expansion portion to expand and deploy toward the front of the vehicle between the body side portion and the vehicle seat. Certain inflatable parts do not inflate and deploy extremely slowly than other inflatable parts. In particular, since the initial inflating and deploying of the central inflating part is ensured by the inflating of the inner bag, the inflating and deploying of the central inflating part is not extremely slow compared to other inflating parts. And each part of a passenger | crew is restrained by the corresponding expansion part of an airbag, and is protected from the said impact.

  Moreover, when the inner bag is arranged so that the front end of the inner bag is positioned at the above-described position, the inner bag is inflated at least near the side of the occupant when the airbag is inflated and deployed. In this respect, the inner bag is different from the inner tube that does not expand near the side of the occupant. Therefore, the inner bag will also function to restrain the occupant and protect it from impact, and the restraint and protection performance will be improved compared to the one that restrains and protects the occupant with only the airbag without the inner bag. To do.

  According to a second aspect of the present invention, in the first aspect of the present invention, at least one of the upper opening, the lower opening, and the intermediate opening has a flow area different from that of the other openings. Is the gist.

  Since the flow passage areas of the upper opening, the lower opening, and the middle opening have the above relationship, at least one of the upper inflating part, the lower inflating part, and the central inflating part is different from the other inflating parts. Inflate and deploy with internal pressure. Therefore, by appropriately setting the flow passage area of each opening, the inflatable portion corresponding to the high impact resistance portion of the side portion of the occupant is inflated and deployed at a high internal pressure, and corresponds to the low impact resistance portion. It is possible to inflate and deploy the inflatable portion with a low internal pressure.

  The invention according to claim 3 is the invention according to claim 1 or 2, wherein only the circulation of the inflation gas from the inner bag to the upper inflation portion is provided in the vicinity of the upper opening in the upper inflation portion. The gist of the invention is that an upper valve is provided to allow the above.

  According to the above configuration, the upper valve adjusts the internal pressure of the central expansion portion when the body side portion enters the vehicle due to the impact and the central expansion portion in the expanded state is pressed against the side of the occupant. Demonstrate the pressure regulation function. That is, the upper valve allows the expansion gas to flow from the central expansion portion to the upper expansion portion, but restricts the expansion gas in the upper expansion portion from flowing (backflowing) to the central expansion portion. When the expansion gas in the central expansion portion flows to the upper expansion portion and the backflow is restricted, the internal pressure of the central expansion portion decreases and the internal pressure of the upper expansion portion increases. Therefore, a phenomenon in which the internal pressure of the central inflating portion excessively rises when restraining the passenger is suppressed. Further, the internal pressure of the upper inflating portion that has been increased to an appropriate internal pressure for protecting the occupant is maintained without decreasing.

  The invention according to claim 4 is the invention according to claim 3, wherein the central expansion portion and the upper expansion portion are formed independently of each other, and the center expansion portion and the upper expansion portion are arranged between the central expansion portion and the upper expansion portion. The gist of the circulation of the expansion gas is only through the upper valve.

  According to the above configuration, the expansion gas only flows through the upper valve between the central expansion portion and the upper expansion portion, and the expansion gas does not pass through the upper valve between the central expansion portion and the upper expansion portion. Never circulates. Therefore, the pressure regulation function of the upper valve is not impaired due to the flow of the expansion gas, and the effect of the invention of claim 3 is further ensured.

  According to a fifth aspect of the present invention, in the invention according to any one of the first to fourth aspects, the inflation from the inner bag to the lower inflatable portion is in the vicinity of the lower opening in the lower inflatable portion. The gist of the invention is that a lower valve that allows only the flow of the working gas is provided.

  According to the above configuration, when the body side portion enters the vehicle due to the impact and the central expansion portion in the expanded state is pressed against the side of the occupant, the lower valve adjusts the internal pressure of the central expansion portion. Demonstrate the pressure regulation function. That is, the lower valve allows the expansion gas to flow from the central expansion portion to the lower expansion portion, but restricts the expansion gas in the lower expansion portion from flowing (backflowing) to the central expansion portion. When the expansion gas in the central expansion portion flows to the lower expansion portion and the backflow is restricted, the internal pressure of the central expansion portion decreases and the internal pressure of the lower expansion portion increases. For this reason, excessive increase in the internal pressure of the central inflating portion during occupant restraint is suppressed. Further, the internal pressure of the lower inflating portion that has been increased to an appropriate internal pressure for protecting the passenger is maintained without lowering.

  The invention according to claim 6 is the invention according to claim 5, wherein the central expansion portion and the lower expansion portion are formed independently of each other, and the center expansion portion and the lower expansion portion are arranged between the central expansion portion and the lower expansion portion. The gist of the circulation of the expansion gas is through the lower valve only.

  According to the above configuration, between the central expansion portion and the lower expansion portion, the expansion gas only flows through the lower valve, and the expansion gas does not pass through the lower valve between the central expansion portion and the lower expansion portion. Will not flow. Therefore, the pressure regulation function of the lower valve is not impaired due to the flow of the expansion gas, and the effect of the invention of claim 5 is further ensured.

  The invention according to claim 7 is the invention according to any one of claims 1 to 6, wherein the central inflating portion is inflated and deployed near a side of the chest of the occupant, and the upper inflating portion is the occupant. The lower inflatable part is inflated and deployed in the vicinity of the side of the occupant's waist.

  The central inflating portion, the upper inflating portion, and the lower inflating portion are inflated and deployed at the above-described locations, so that the shoulder portion, the chest portion, and the waist portion are restrained by the inflating portions that inflate and deploy in the vicinity of the side portions, and are protected from impact. .

  The invention according to claim 8 is the gist of the invention according to claim 7, wherein the flow path area of the intermediate opening in the inner bag is set smaller than the flow path area of the upper opening. To do.

  The flow rate per unit time of the inflating gas flowing through the intermediate opening to the central inflating portion through the above-described setting for the flow path area is the unit of the inflating gas flowing through the upper opening to the upper inflating portion. Less than the flow rate per hour. For this reason, the central expansion portion expands and expands later than the upper expansion portion. Along with this, the internal pressure of the central inflatable portion rises later than the internal pressure of the upper inflatable portion, and the internal pressure of the central inflatable portion becomes lower than the internal pressure of the upper inflatable portion at the initial stage of inflation of the airbag. As a result, the shoulder part with high impact resistance is restrained and protected by the upper inflating part with high internal pressure, and the chest part with low impact resistance is softly restrained and protected by the central inflating part with low internal pressure. The

  The invention according to claim 9 is the invention according to claim 7 or 8, wherein the flow passage area of the intermediate opening in the inner bag is set smaller than the flow passage area of the lower opening. The gist.

  The flow rate per unit time of the expansion gas flowing through the intermediate opening to the central expansion section through the above setting for the flow path area is the unit of the expansion gas flowing through the lower opening to the lower expansion section. Less than the flow rate per hour. Therefore, the central expansion portion expands and develops later than the lower expansion portion. Along with this, the internal pressure of the central inflating portion rises later than the internal pressure of the lower inflating portion, and the internal pressure of the central inflating portion becomes lower than the internal pressure of the lower inflating portion at the initial stage of inflation of the airbag. As a result, the waist part having high impact resistance is restrained and protected by the lower inflating part having high internal pressure, and the chest part having low impact resistance is softly restrained and protected by the central inflating part having low internal pressure. .

  The invention according to a tenth aspect is the invention according to any one of the first to ninth aspects, wherein the airbag in the stowable configuration is configured such that a front portion of the airbag in a deployed state is disposed forward of the inflator. Folding from the rear toward the rear to form an intermediate form that is elongated in the substantially vertical direction, and further folding the upper part of the airbag of the intermediate form from the inflator forward and downward to be positioned in front of the inner bag. The gist is that it is formed.

  According to said structure, the dimension of the front-back direction of the airbag of an intermediate | middle form becomes small by folding a front side part from the front to the back rather than the inflator of the airbag of a deployment state. Further, by folding back the upper portion of the intermediate form airbag so as to satisfy the above-described conditions, the vertical dimension of the storage form airbag is reduced. As described above, in the storage mode, the airbag is compact in the front-rear direction and the vertical direction, and can be easily stored even in a narrow storage portion.

  Further, when the inflation gas is ejected from the inflator to the airbag in the storage form, the inflation gas is first supplied to the inner bag as described above, and the inner bag is inflated. The outer central inflatable portion is inflated by the inflating inner bag. By the central inflating portion that is inflated, a portion located on the front side thereof, that is, a portion folded back forward and downward in the intermediate airbag is pushed forward. This pressing promotes the elimination of the folded state of the folded portion.

  According to an eleventh aspect of the present invention, in the invention according to the tenth aspect, at least a part of the folded portion of the airbag in the intermediate form is more than a boundary portion between the central inflating portion and the upper inflating portion. Is also located below.

  The upper portion of the intermediate airbag is folded back so as to satisfy the above-described condition, so that the folded portion is positioned on the front side of the central inflatable portion and the inner bag. The folded portion reliably receives the pressing force by the inflating inner bag and the central inflating portion to cancel the folded state, and the effect of the invention of claim 10 can be obtained with certainty.

  According to the side airbag device of the present invention, a specific inflating part is inflated and deployed extremely later than other inflating parts while inflating and inflating each inflating part with an internal pressure corresponding to the impact resistance of the occupant's site. The airbag deployment performance can be improved by suppressing the above.

Hereinafter, an embodiment embodying the present invention will be described with reference to FIGS. In the following description, the traveling direction (forward direction) of the vehicle will be described as the front.
As shown in at least one of FIGS. 1 to 3A, a vehicle seat 12 is disposed in the vicinity of the vehicle side of the body side portion 11 in the vehicle. Here, the body side part 11 refers to the member arrange | positioned at the side part of a vehicle. 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 (back portion) 14 that stands up from the rear side of the seat cushion 13 and has an inclination adjustment mechanism (not shown). Yes. A storage portion 15 is provided on the side of the seatback 14 on the vehicle exterior side, and an airbag module AM that is a main part of the side airbag device is stored in the storage portion 15. The position of the storage unit 15 is in the vicinity of the rear of the occupant P seated on the vehicle seat 12. The airbag module AM includes an inflator assembly 20 (see FIG. 5) and an airbag 30 as main components.

  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 referred to as “vertical direction”, and the direction perpendicular to the substantially longitudinal direction of the vehicle with respect to this direction is referred to as “front / rear direction”. Normally, since the seat back 14 is used in a state of being inclined rearward, 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>
FIG. 4 schematically shows the airbag module AM together with the occupant P in a state where the airbag 30 is deployed in a planar shape without being filled with the inflation gas G (hereinafter referred to as “planar deployed state”). . 5 shows the inflator assembly 20 disposed in the airbag 30 of FIG. FIG. 6 shows the inflator assembly 20 shown in FIG. As shown in at least one of FIGS. 4 to 6, the inflator assembly 20 includes an inflator 21 as a gas generation source and a retainer 22 that covers the inflator 21 from the outside. The inflator 21 has a substantially cylindrical shape elongated in the substantially vertical direction, and a gas generating agent (not shown) that reacts in response to an operation signal from the outside to generate an expansion gas G is accommodated therein. .

  A harness (not shown) serving as an operation signal application wiring to the inflator 21 is connected to the top of the inflator 21. Further, on the lower end side of the inflator 21, a gas ejection portion 23 having a substantially cylindrical shape and having a smaller diameter than other portions is provided. A plurality of gas ejection holes 24 through which the expansion gas G generated by the gas generating agent is ejected in a direction (radial direction) perpendicular to the axis L1 of the inflator 21 is provided on the outer peripheral surface of the gas ejection portion 23. .

  The inflator 21 may be a type in which the partition wall of the high-pressure gas cylinder filled with the high-pressure gas is broken with explosives or the like and the expansion gas G is ejected instead of the type using the gas generating agent. .

  On the other hand, the retainer 22 is a member that functions as a diffuser and has a function of fixing the inflator 21 together with the airbag 30 to the seat frame 16 (see FIG. 6) in the seat back 14. 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. At least the lower end side of the retainer 22 is an open end 22A (see FIG. 5), and at least a part of the expansion gas G ejected from the gas ejection portion 23 is allowed to pass substantially downward. In FIG. 5, in order to illustrate the open end 22 </ b> A, a part of the lower end portion of the retainer 22 is broken and illustrated.

  In the retainer 22, a window portion 25 is provided above the open end 22 </ b> A and in the vicinity of the gas ejection portion 23 of the inflator 21. The window portion 25 allows at least a portion of the inflation gas G ejected from the gas ejection portion 23 to pass substantially forward.

  A plurality of (two in this embodiment) bolts 26 are fixed to the retainer 22 as locking members for attaching the retainer 22 to the seat frame 16. In other words, the bolt 26 is indirectly fixed to the inflator 21 via the retainer 22. These bolts 26 extend in a direction perpendicular to the axis L <b> 1 of the inflator 21.

The inflator assembly 20 may be one in which an inflator 21 and a retainer 22 are integrated.
<Airbag 30>
As shown in at least one of FIGS. 1 to 3A, the airbag 30 is impacted outward by a side collision or the like while the vehicle is running (downward in FIG. 2, leftward in FIG. 3A). When it is added to the body side part 11 from the above, it is inflated and deployed by the inflating gas G from the inflator 21 (see FIGS. 5 and 6). The airbag 30 jumps out from the storage portion 15 toward the front of the vehicle in a state where a part of the airbag 30 remains in the storage portion 15, and is inflated and deployed in the gap G1 between the vehicle seat 12 and the body side portion 11. By doing so, the occupant P is restrained and protected from the impact.

  FIG. 7 shows the internal structure of the airbag module AM. However, in FIG. 7, unlike FIG. 4, the internal structure of the airbag module AM when the seat back 14 is erected substantially vertically is shown. Further, FIG. 7 shows the inner half of the airbag module AM (excluding the inflator assembly 20). As shown in FIG. 7, the airbag 30 includes a first inflatable body 31 and a second inflatable body 32 each having a bag shape. Many portions of the first expansion body 31 are located above the second expansion body 32.

  Next, referring to FIGS. 8 to 10 in addition to FIGS. 4 and 7, (i) the form of the second expansion body 32 alone, and (ii) the first expansion body 31 and the second expansion body 32. Description will be made in the order of the form of the first expansion body 31 alone, and (iii) the form in which the first expansion body 31 and the second expansion body 32 are combined.

  Here, FIG. 8 shows the vehicle interior portions of the first inflatable body 31 and the second inflatable body 32 constituting the airbag 30 in FIG. 7 in a state where they are separated in the vertical direction. Further, FIG. 9 shows a state in which the second expansion body 32 and the like are expanded in a planar shape, and FIG. 10 shows a state in which the first expansion body 31 and the like are expanded in a planar shape.

(I) Form of the second inflatable body 32 alone As shown in at least one of FIGS. 4 and 7 to 9, the second inflatable body 32 is a panel cloth (also called a base cloth) 33 made of one piece of cloth. It is formed using. As the panel cloth 33, 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 panel cloth 33 is overlapped in the vehicle width direction by being folded in two along a fold line 34 set at the center portion thereof. Here, in order to distinguish the two overlapped portions of the airbag 30, the one located on the inside of the vehicle is referred to as the fabric portion 35, and the one located on the outside of the vehicle is referred to as the fabric portion 36. In the panel cloth 33, the outer shapes of the cloth parts 35 and 36 are in a line-symmetric relationship with respect to the folding line 34 as an axis of symmetry.

  Both fabric parts 35 and 36 are connected by a peripheral connecting part 37 provided at the peripheral part except for the upper part thereof. The peripheral joint portion 37 is formed by stitching the fabric portions 35 and 36 together. In the two fabric portions 35 and 36, a portion that is not joined (sewn) by the peripheral joint portion 37, more precisely between the partition joint portion 61 described later, is used for the expansion of the second expansion body 32. An exhaust port 40 for discharging the gas G to the outside of the airbag 30 is provided. In addition, the peripheral joint part 37 is provided also in the part of this exhaust port 40, both the fabric parts 35 and 36 may be couple | bonded, and the same exhaust port 40 may be block | closed.

  The lower part of the second inflatable body 32 and surrounded by the peripheral edge coupling part 37 is inflated and deployed with a relatively high internal pressure mainly between the waist part PP and the body side part 11 of the occupant P. It is a “lower expansion part EL” that restrains and protects PP. The lower inflating portion EL is located below the central inflating portion EC described later. Further, an upper portion in the second expansion body 32 and a portion where the peripheral joint portion 37 is not provided constitutes an insertion portion 38. In the insertion portion 38, a portion in the vicinity of the front side of the fold line 34 constitutes an inflator storage portion 39 for storing the inflator assembly 20 described above.

  Both fabric portions 35 and 36 are not stitched together at the front edge portion 38F of the insertion portion 38. The inflator storage part 39 and the outside (front part) of the insertion part 38 are connected (connected).

(Ii) Form of the first expansion body 31 alone As shown in at least one of FIGS. 4, 7, 8, and 10, the first expansion body 31 is made of the same material as the second expansion body 32. It is formed using a panel cloth 41 made of one piece of cloth. The panel cloth 41 is overlapped in the vehicle width direction by being folded in two along a fold line 42 set at the center portion thereof. Here, in order to distinguish the above-described two overlapped portions of the first inflatable body 31, the one located on the vehicle interior side is referred to as the fabric portion 43, and the one located on the vehicle exterior side is referred to as the fabric portion 44. . In the panel cloth 41, the outer shapes of the cloth parts 43 and 44 are in a line-symmetric relationship with each other with the folding line 42 as the axis of symmetry.

  Both fabric parts 43 and 44 are connected by a peripheral connecting part 45 provided on the peripheral part except for the lower part thereof. A lower portion of the first inflatable body 31 and in the vicinity of the front side of the fold line 42 constitutes an insertion portion 47.

  A tether 51 that extends substantially in the front-rear direction is provided in the upper part of the first expansion body 31. As shown in at least one of FIGS. 7, 10, and 11, the tether 51 includes a pair of component pieces 52 and 53 in the vehicle width direction. Each of the component pieces 52 and 53 is formed in a rectangular shape that is longer in the front-rear direction than in the up-down direction by the fabric, like the first inflatable body 31. The front end portions of the constituent pieces 52 and 53 reach the upper front ends of the fabric portions 43 and 44, and the rear end portions are spaced forward from the upper rear ends of the fabric portions 43 and 44. The vehicle interior component piece 52 is coupled to the vehicle interior fabric portion 43 by a lower coupling portion 54 provided so as to extend in the front-rear direction along the lower edge portion thereof. Further, the vehicle exterior component piece 53 is coupled to the vehicle exterior fabric portion 44 by a lower coupling portion 55 provided so as to extend in the front-rear direction along the lower edge portion thereof. The front ends of these lower coupling portions 54, 55 reach the upper front end of the peripheral coupling portion 45, and the rear ends are located near the center in the front-rear direction of the first expansion body 31. Furthermore, the two component pieces 52 and 53 are coupled to each other by an upper coupling portion 56 provided so as to extend in the front-rear direction along the upper edge portion thereof. In the present embodiment, the lower coupling portions 54 and 55 and the upper coupling portion 56 are formed by stitching using a sewing thread. In this way, the tether 51 composed of the two component pieces 52 and 53 is bridged between the two fabric portions 43 and 44 of the first inflatable body 31. In the tether 51, when the airbag 30 is not inflated, most of the component pieces 52 and 53 are overlapped (see FIG. 11A).

  As shown in FIG. 4, the internal space of the first inflatable body 31 is divided into an upper inflating portion EU and a lower central inflating portion EC with the tether 51 as a boundary. The upper inflating part EU restrains and protects the shoulder part PS by inflating and deploying with a relatively high internal pressure mainly between the shoulder part PS and the body side part 11 of the occupant P (see FIG. 3A). Further, the central inflating part EC is located between the chest part PT and the abdomen PB of the occupant P (referred to as “chest part PT etc.” when these need not be distinguished) and the body side part 11, and the upper inflating part EU. The chest PT and the like are restrained and protected by inflating and deploying at a lower internal pressure (see FIG. 3A). The central expansion part EC is located below the upper expansion part EU. The tether 51 also has a function of regulating the thickness when the first expansion body 31 is expanded in the vehicle width direction.

  Instead of the tether 51, the inner space of the first inflatable body 31 may be partitioned into an upper inflatable portion EU and a central inflatable portion EC by a seam. The seam is formed by joining the fabric portions 43 and 44 in a state where they are close to each other. In many cases, the seam is formed by stitching together the fabric portions 43 and 44 with a sewing thread.

  In the first inflatable body 31, an annular closing portion 57 is provided at a location corresponding to the arm portion PA of the occupant P, here a location near the rear end of the tether 51. The closing portion 57 is for allowing an upper valve 80 (described later) provided in the upper opening OU to function as a check valve, and is formed by sewing both fabric portions 43 and 44 in an annular shape with sewing threads.

(Iii) Form in which the first expansion body 31 and the second expansion body 32 are combined As shown in at least one of FIGS. 7 to 10, the insertion portion 38 of the second expansion body 32 has its folding line 34 connected to the first expansion body 34. The first inflatable body 31 is inserted and arranged in the inserted portion 47 in a state of being substantially matched with the fold line 42. With this arrangement, the insertion portion 47 is superimposed on the outside of the insertion portion 38.

  The vehicle interior portion of the insertion portion 38 is coupled to the vehicle interior portion of the insertion portion 47 by an inner coupling portion 58. Similarly, the vehicle outer side portion of the insertion portion 38 is coupled to the vehicle outer side portion of the inserted portion 47 by the inner coupling portion 59. These inner connecting portions 58 and 59 simply connect the inner portions of the insertion portion 38 and the inserted portion 47 and also connect the outer portions to each other, and connect the inner portion and the outer portion to each other. It does not bind to

  Further, the vehicle interior portion and vehicle exterior portion of the insertion portion 38 and the vehicle interior portion and vehicle exterior portion of the insertion portion 47 that overlap the outside are integrally coupled by a partition coupling portion 61 that extends substantially in the front-rear direction. ing. By the partition coupling portion 61, the internal space of the first expansion body 31 and the internal space of the second expansion body 32 are partitioned vertically. That is, simply inserting the insertion portion 38 into the inserted portion 47 causes the internal space of the first expansion body 31 and the internal space of the second expansion body 32 to communicate with each other. By being provided, both internal spaces are partitioned into two vertically. Furthermore, in the present embodiment, the vehicle interior portion and vehicle exterior portion of the insertion portion 38 and the vehicle interior portion and vehicle exterior portion of the insertion portion 47 that overlap the outside are the above-described peripheral edges of the first inflatable body 31. It is integrally coupled by a part of the rear portion of the coupling portion 45 (a location indicated by reference numeral 45A).

  The second inflatable body 32, which is partitioned by the section connecting portion 61 and independent from the first inflatable body 31, is inflated and deployed at a relatively high internal pressure mainly in the vicinity of the outside of the lumbar portion PP of the occupant P, thereby forming the lumbar portion PP. It is an expansion part (lower expansion part EL) for restraining and protecting.

  As shown in FIG. 4, the above-described inflator assembly 20 is disposed in the inflator accommodating portion 39 of the airbag 30 in a posture that is inclined so as to become lower toward the front side. Most of the inflator assembly 20 is located in the central inflation EC. Both bolts 26 fixed to the retainer 22 are inserted into rear end portions of the fabric portions 35 and 43 on the vehicle interior (including the fabric portion 72 on the vehicle interior side of the inner bag 70 described later) (see FIG. 5 and FIG. 5). (See FIG. 6). The airbag 30 is fastened in an airtight state to the upper end portion of the inflator assembly 20 by an annular fastener (not shown) mounted outside the airbag 30 in the vicinity of the peripheral edge coupling portion 45A.

  Furthermore, in this embodiment, as shown in at least one of FIGS. 7, 9, and 10, an inner bag 70 and an upper valve 80 and a lower valve 90 each comprising a check valve are provided inside the airbag 30. Are arranged. Next, these members will be described.

<Inner bag 70>
The inner bag 70 mainly guides the inflation gas G from the inflator 21 in three directions, substantially upward, substantially forward, and substantially downward, within the airbag 30, and is inflated by itself so that the central inflation of the airbag 30 is achieved. The rear half of the part EC is for inflating at the initial stage of deployment, and is arranged in the central inflating part EC in a manner that satisfies the following condition (I). The condition (I) is that when the airbag 30 is inflated and deployed and arranged in a vertical state, the front end 70F of the inner bag 70 is behind the front end ECF of the central inflating part EC and in the vehicle seat 12. It is located ahead of the front end 14F of the seat back 14. In the present embodiment, the front end edge 71 of the inner bag 70 extends substantially linearly in the vertical direction in the vicinity of the center portion in the front-rear direction of the first inflatable body 31. The upper end of the front end edge 71 is located in the vicinity of the front of the closing part 57, and the lower end of the front end edge 71 is located at the lower part (lower end) of the central expansion part EC (first expansion body 31). In addition, the rear end of the inner bag 70 is located at substantially the same location as the rear end of the first inflatable body 31.

  Unlike the first inflatable body 31 and the second inflatable body 32 described above, the inner bag 70 includes a fabric portion 72 located on the inner side of the vehicle and a fabric portion 73 located on the outer side of the vehicle in a state independent of the fabric portion 72. It has. The fabric portion 72 on the vehicle inner side is coupled to the fabric portion 43 on the vehicle interior side of the first inflatable body 31 by the upper portion 58U of the inner coupling portion 58 described above, and the first inflatable body 31 by the remaining portion 58L of the inner coupling portion 58. The vehicle interior side fabric portion 43 and the vehicle interior side fabric portion 35 of the second expansion body 32 are coupled to each other. Further, the upper end portion of the fabric portion 72 on the vehicle interior side is coupled to the fabric portion 43 on the vehicle interior side of the first inflatable body 31 by another inner coupling portion 74 that extends linearly in the vehicle longitudinal direction. The front end of the inner coupling portion 74 reaches the closing portion 57, and the rear end reaches the upper rear end edge of the fabric portion 43.

  Similarly, the outer fabric portion 73 of the inner bag 70 is coupled to the outer fabric portion 44 of the first inflatable body 31 by the above-described upper portion 59U of the inner coupling portion 59 and the remaining portion of the inner coupling portion 59. 59L is connected to the fabric portion 44 on the vehicle exterior side of the first expansion body 31 and the fabric portion 36 on the vehicle exterior side of the second expansion body 32. The upper end portion of the fabric portion 73 on the vehicle exterior side is coupled to the fabric portion 44 on the vehicle exterior side of the first inflatable body 31 by another inner coupling portion 75 that extends linearly in the vehicle longitudinal direction. The front end of the inner coupling portion 75 reaches the closing portion 57, and the rear end reaches the upper rear end edge of the fabric portion 44.

  The two fabric portions 72 and 73 of the inner bag 70 are connected to each other by a connecting portion 76 provided along their front edge portions (see FIG. 7). The joint portion 76 is not provided at a substantially central portion in the up-down direction of the two fabric portions 72 and 73, and a portion where the joint portion 76 is not provided is an intermediate portion opening OC. The inner space of the inner bag 70 is communicated with the central inflating part EC through the intermediate part opening OC. The intermediate portion opening OC opens toward the portion where the inner bag 70 is not disposed in the central inflating portion EC, here, toward the front.

  Further, both fabric portions 72 and 73 of the inner bag 70 are integrally coupled to both the constituent pieces 52 and 53 of the tether 51 and both the fabric portions 43 and 44 of the first inflating body 31 by the closing portion 57 described above. . In addition, the two fabric portions 72 and 73 of the inner bag 70 are divided into the two fabric portions 43 and 44 of the first inflatable body 31 and the two fabric portions 35 and 36 of the second inflatable body 32 by the partition coupling portion 61 described above. They are joined together.

  FIG. 12 shows the fabric portion 72 on one side (the vehicle interior side) of the inner bag 70. As shown in at least one of FIGS. 7 and 12, the inner bag 70 is, at its upper end, more precisely, between the closing portion 57 and the upper rear end of the peripheral coupling portion 45 in the first inflatable body 31. , The inner and outer joint portions 74 and 75 are connected to the fabric portions 43 and 44, but the fabric portions 72 and 73 are not connected to each other. The unbonded portion between the fabric portions 72 and 73 in the inner bag 70 is referred to as an “upper opening OU”. The inner space of the inner bag 70 communicates with the upper inflating part EU through the upper opening OU. The upper opening OU opens toward the upper expansion part EU, here substantially upward.

  Further, the inner bag 70 is internally coupled to the fabric portions 35 and 36 at its lower end portion, more precisely between the rear end of the partition coupling portion 61 and the fold line 34 of the second inflatable body 32. Although it couple | bonds by the parts 58 and 59, the fabric parts 72 and 73 are not couple | bonded. The unbonded portion between the fabric portions 35 and 36 in the inner bag 70 is referred to as a “lower opening OL”. The inner coupling portions 58 and 59 intersect with the peripheral coupling portion 45 (see FIG. 7). The inner space of the inner bag 70 communicates with the lower inflating part EL through the lower opening OL. The lower opening OL opens toward the lower expansion portion EL, here substantially downward.

  Further, in the present embodiment, SC <SU and SC <SL, where SC is the channel area of the middle opening OC, SU is the channel area of the upper opening OU, and SL is the channel area of the lower opening OL. Each flow passage area SC, SU, SL is set so as to satisfy the above relationship. The channel areas SU and SL are set to the same size.

<Upper valve 80>
As shown in at least one of FIGS. 10, 13, and 15 (A), the upper valve 80 is a valve that allows only the flow of the inflation gas G from the inner bag 70 to the upper inflation portion EU. It is provided in the vicinity of the upper opening OU in the upper expansion part EU. The position of the upper valve 80 is the rear side of the vehicle when the airbag 30 is deployed.

  The upper valve 80 includes a fabric portion 81 located on the inner side of the vehicle and a fabric portion 82 located on the outer side of the vehicle in a state independent of the fabric portion 81. The lower end portions of the fabric portions 81 and 82 are disposed inside the upper end of the inner bag 70 in the upper opening OU.

  For coupling the fabric portions 81 and 82 to the inner bag 70 and the airbag 30, the above-described inner coupling portions 74 and 75 and a part of the closing portion 57 are used. That is, the lower end portion of the fabric portion 81 on the vehicle interior is coupled to the fabric portion 43 on the vehicle interior side of the first inflatable body 31 together with the fabric portion 72 on the vehicle interior side of the inner bag 70 by the vehicle interior coupling portion 74. ing. Further, the lower end portion of the fabric portion 82 on the vehicle exterior side is coupled to the fabric portion 44 on the vehicle exterior side of the first inflatable body 31 together with the fabric portion 73 on the vehicle exterior side of the inner bag 70 by the inner coupling portion 75 on the vehicle exterior side. ing. In this case, the inner coupling portion 74 sews (co-sews) the fabric portions 81 and 72 on the inner side of the upper valve 80 and the inner bag 70 to the fabric portion 43 on the inner side of the first inflatable body 31. It will be formed by. Further, the inner coupling portion 75 is formed by sewing (co-sewing) the fabric portions 82 and 73 on the vehicle exterior side of the upper valve 80 and the inner bag 70 to the fabric portion 44 on the vehicle exterior side of the first inflatable body 31. It will be formed. The lower end portion of the fabric portion 81 on the vehicle interior side and the lower end portion of the fabric portion 82 on the vehicle exterior side are not coupled to each other.

  In addition, the front ends of the fabric portions 81 and 82 are part of the closing portion 57, and together with the fabric portions 72 and 73 of the inner bag 70 and the component pieces 52 and 53 of the tether 51, the first inflatable body. The two fabric portions 43 and 44 are coupled to each other. In this case, the closing portion 57 is formed by sewing (co-sewing) the first inflatable body 31, the tether 51, the inner bag 70, and the upper valve 80.

  Further, a coupling portion 83 extending in the vertical direction is provided at the rear ends of the fabric portions 81 and 82, and the fabric portions 81 and 82 are coupled to each other by the coupling portion 83. The lower end 83L (see FIG. 13) of the joint portion 83 reaches the upper end portions of the fabric portions 72 and 73 of the inner bag 70, and the rear lower ends of the fabric portions 81 and 82 are also coupled to the inner bag 70. The joint portion 83 is formed by stitching the rear ends of the fabric portions 81 and 82 at the portion of the upper valve 80 that is disposed outside the inner bag 70. Further, the coupling portion 83 is formed by stitching the upper valve 80 and the inner bag 70 at a portion (lower end 83 </ b> L) disposed in the inner bag 70 in the upper valve 80.

  An inclined portion 84 that is inclined so as to be lower toward the front side is provided on the upper portions of the fabric portions 81 and 82. In the inclined portion 84, the fabric portions 81 and 82 are not connected to each other. In addition, as described above, the fabric portions 81 and 82 are coupled to the corresponding fabric portions 72, 73, 43, and 44 of the inner bag 70 and the first inflatable body 31 at the lower ends thereof. The parts 81 and 82 are not joined to each other. Accordingly, the upper valve 80 has a cylindrical shape opened at the inclined portion 84 and the lower end portion.

  As described above, since the fabric portion 81 on the vehicle interior side is coupled to the fabric portion 43 on the vehicle interior side of the first inflatable body 31 by the inner coupling portion 74, the inflation gas G passes between the fabric portions 81 and 43. It is impossible to flow through the upper inflating part EU to the central inflating part EC or vice versa. Similarly, since the fabric portion 82 on the vehicle exterior side is coupled to the fabric portion 44 on the vehicle exterior side of the first expansion body 31 by the inner coupling portion 75, the inflation gas G passes between the fabric portions 82 and 44. It is impossible to flow from the upper expansion portion EU toward the central expansion portion EC or in the opposite direction. The expansion gas G can flow from the upper expansion portion EU toward the central expansion portion EC or in the opposite direction only by passing between the fabric portions 81 and 82 of the upper valve 80 as a flow path. It is.

  Here, the lower ends of the fabric portions 81 and 82 are located in the vicinity of the rear of the tether 51 and face the central expansion portion EC. Further, the inclined portions 84 of the fabric portions 81 and 82 are located in the lower portion in the upper inflating portion EU and in the vicinity of the rear of the tether 51.

  Further, as described above, the fabric portions 81 and 82 are coupled to the fabric portions 43 and 44 of the first inflatable body 31 at the lower end portion and the front end portion thereof. Both fabric portions 81 and 82 are not coupled to the fabric portions 43 and 44 at other locations. A part (upper part) of the upper valve 80 having such a configuration is easier to bend than other parts. The above portion (upper portion) of the upper valve 80 expands to open the upper opening OU when the internal pressure of the central expansion portion EC is higher than the internal pressure of the upper expansion portion EU (see FIG. 15B), and when it is lower, the upper opening The bendable portion 88 is bent so as to close the OU (see FIG. 15C).

<Lower valve 90>
As shown in at least one of FIGS. 9, 14 and 16A, the lower valve 90 is a valve that allows only the flow of the inflation gas G from the inner bag 70 to the lower inflation portion EL. It is provided in the vicinity of the lower opening OL in the expansion part EL. The position of the lower valve 90 is the rear side of the vehicle when the airbag 30 is deployed. The lower valve 90 basically has the same configuration as the upper valve 80 described above. That is, the lower valve 90 includes a fabric portion 91 located on the inner side of the vehicle, and a fabric portion 92 located on the outer side of the vehicle in a state independent of the fabric portion 91. Each upper end part of the fabric parts 91 and 92 is arrange | positioned inside the lower end of the inner bag 70 in lower opening OL.

  In order to couple the fabric portions 91 and 92 with the inner bag 70 and the airbag 30, a part of the inner coupling portions 58 and 59 and a portion of the partition coupling portion 61 are used. That is, the upper end portion of the fabric portion 91 on the vehicle interior side is connected to the vehicle interior sides of the first inflatable body 31 and the second inflatable body 32 together with the fabric portion 72 on the vehicle interior side of the inner bag 70 by the inner coupling portion 58 on the vehicle interior side. The fabric portions 43 and 35 are coupled to each other. In addition, the upper end portion of the fabric portion 92 on the vehicle exterior side is connected to the vehicle exterior side of the first inflatable body 31 and the second inflatable body 32 together with the fabric portion 73 on the vehicle exterior side of the inner bag 70 by the inner coupling portion 59 on the vehicle exterior side. Are connected to the fabric portions 44 and 36. In this case, the inner coupling portion 58 includes the fabric portions 91 and 72 on the vehicle interior side of the lower valve 90 and the inner bag 70, and the fabric portions 43 and 35 on the vehicle interior side of the first expansion body 31 and the second expansion body 32. It is formed by sewing (co-sewing). In addition, the inner coupling portion 59 converts the fabric portions 92 and 73 on the vehicle exterior side of the lower valve 90 and the inner bag 70 to the fabric portions 44 and 36 on the vehicle exterior side of the first expansion body 31 and the second expansion body 32. It is formed by sewing (co-sewing). The upper end portion of the fabric portion 91 on the vehicle interior side and the upper end portion of the fabric portion 92 on the vehicle exterior side are not coupled to each other.

  Further, the front end portions of the fabric portions 91 and 92 are coupled to the first inflatable body 31 and the second inflatable body 32 together with the inner bag 70 by a part of the partition coupling portion 61. In this case, the partition coupling portion 61 is formed by sewing (co-sewing) the first inflatable body 31, the second inflatable body 32, the inner bag 70, and the lower valve 90.

  Further, a coupling portion 93 extending in the vertical direction is provided at the rear end portions of the fabric portions 91 and 92 in the lower valve 90, and the fabric portions 91 and 92 are coupled to each other by the coupling portion 93. . The upper end 93U (see FIG. 14) of the coupling portion 93 reaches the lower end portion of the inner bag 70, and the upper rear ends of both fabric portions 91 and 92 are also coupled to the inner bag 70. The joint portion 93 is formed by stitching the rear ends of the fabric portions 91 and 92 at the portion of the lower valve 90 disposed outside the inner bag 70. Further, the coupling portion 93 is formed by stitching the lower valve 90 and the inner bag 70 at a portion (upper end 93U) disposed in the inner bag 70 in the lower valve 90.

  An inclined portion 94 that is inclined so as to be higher toward the front side is provided below the fabric portions 91 and 92. The inclination aspect of the inclined portion 94 is opposite to the inclination aspect of the inclined portion 84 in the upper valve 80. In the inclined portion 94, the fabric portions 91 and 92 are not coupled to each other. In addition, as described above, the fabric portions 91 and 92 have the fabric portions 72, 73, 43, 44, 35, corresponding to the inner bag 70, the first inflatable body 31, and the second inflatable body 32 at their upper end portions. 36, but the fabric portions 91 and 92 are not joined. Therefore, the lower valve 90 has a cylindrical shape opened at the inclined portion 94 and the upper end portion.

  As described above, since the fabric portion 91 on the vehicle interior side is coupled to the fabric portion 35 on the vehicle interior side of the second inflatable body 32 by the inner coupling portion 58, the inflation gas G is supplied to the fabric portions 91, It is impossible to flow through the gap 35 from the lower expansion portion EL toward the central expansion portion EC or in the opposite direction. Similarly, since the fabric portion 92 on the vehicle exterior side is coupled to the fabric portion 36 on the vehicle exterior side of the second expansion body 32 by the inner coupling portion 59, the inflation gas G flows between the fabric portions 92 and 36 on the vehicle exterior side. It is impossible to flow through the lower inflating part EL toward the central inflating part EC or in the opposite direction. The expansion gas G can flow from the lower expansion portion EL toward the central expansion portion EC or in the opposite direction only by passing between the fabric portions 91 and 92 of the lower valve 90 as a flow path. It is.

  Here, the upper ends of the fabric portions 91 and 92 are located in the vicinity of the rear of the partition coupling portion 61 and face the central expansion portion EC. Further, the inclined portions 94 of the fabric portions 91 and 92 are located in the upper part in the lower inflating portion EL and in the vicinity of the rear of the partition coupling portion 61. The retainer 22 of the inflator assembly 20 enters the upper portion of the lower valve 90 only at the lower end portion.

  Further, as described above, the fabric portions 91 and 92 are coupled to the fabric portions 35 and 36 at the upper end portion and the front end portion thereof. Both fabric portions 91 and 92 are not coupled to the fabric portions 35 and 36 at other locations. A part (lower part) of the lower valve 90 having such a configuration is easier to bend than other parts. The above portion of the lower valve 90 expands to open the lower opening OL when the internal pressure of the central expansion portion EC is higher than the internal pressure of the lower expansion portion EL (see FIG. 16B), and closes the lower opening OL when the internal pressure is lower. The bendable portion 98 is bent (see FIG. 16C).

  By the way, the airbag module AM is formed into a compact form (hereinafter referred to as “storage form”) as shown in FIG. 17 by folding the airbag 30 (see FIG. 4) in the above-described flat deployed state. This is because the airbag module AM is securely stored in the storage unit 15 (see FIGS. 1 and 2) having a limited size in the seat back 14.

  As shown in at least one of FIGS. 17 and 18, the airbag 30 in the above-described storage form includes a first folding part 30 </ b> A, a second folding part 30 </ b> B, and a third folding part 30 </ b> C. The first folding portion 30A is partly formed by only folding from the front to the rear with respect to the front portion 101 of the inflator assembly 20 of the airbag 30 in the flatly deployed state shown in FIG. It is. Many of the first folding parts 30A are formed of the central expansion part EC, and are located in the vicinity of the front of the inflator assembly 20. The second folded portion 30B is formed by folding the upper portion 102 forward and lower than the inflator assembly 20 in the airbag 30 in addition to the folding for forming the first folded portion 30A. It is located near the front of the first folding part 30A. In addition to the above-described folding for forming the first folding portion 30A, the third folding portion 30C is formed by folding the lower portion 103 from the inflator assembly 20 further downward from above in the airbag 30. (See FIG. 19).

  The airbag 30 in the flat deployed state is put into a storage form through the following processes (deformation process to intermediate form, formation process of the second folding part, formation process of the third folding part). Next, each step will be described.

<Deformation process to intermediate form>
In this step, as shown in FIG. 18, the front side portion 101 of the airbag 30 in the plane deployed state is bellows-folded with respect to the inflator assembly 20. Here, the bellows folding is one of the folding modes of the airbag 30 in which the airbag 30 is folded in order by a certain width. When the bellows is folded, a plurality of fold lines (mountain fold line 104 and valley fold line 105) extending linearly in a substantially vertical direction with respect to the airbag 30 in a flat deployed state are set. By setting the mountain fold line 104 and the valley fold line 105, the front portion 101 is partitioned into a plurality of folding parts 101A. The interval between the mountain fold line 104 and the valley fold line 105 is the folding width H1 in the bellows fold.

  Then, the airbag 30 is formed in a bellows shape in order of the folding width H1 from the front to the rear in the vicinity of the inflator assembly 20 as indicated by the arrow C along the mountain fold line 104 and the valley fold line 105. Folded. That is, the airbag 30 is folded so that the surfaces sandwiched by adjacent fold lines (mountain fold line 104, valley fold line 105) in the folded portion 101A overlap. After the folding, as shown in FIG. 19A, all of the surfaces of the plurality of folded portions 101A are substantially orthogonal to the front-rear direction. In other words, the folded portions 101A are stacked (bundled) in the front-rear direction, and the airbag 30 is in an intermediate form that is long in the vertical direction and small in the front-rear direction.

<Formation process of 2nd folding part>
As shown in at least one of FIGS. 17 and 19A and 19B, in this step, in the airbag 30 of the intermediate form, the upper portion 102 of the inflator assembly 20 satisfies the condition (II). At the front and bottom. The condition (II) is that at least a part of a folded portion 106, which will be described later, of the upper portion 102 is positioned below the boundary portion 107 between the central expansion portion EC and the upper expansion portion EU. In other words, the condition (II) is that the lower end 106L of the folded portion 106 is located at a position lower than the boundary portion 107. Here, a single fold line 108 extending linearly in the vehicle width direction is set to the upper portion 102 above the boundary portion 107. In the upper portion 102, the portion above the fold line 108 is folded back forward and downward along the fold line 108. By this folding, a second folded portion 30B is formed near the front of the first folded portion 30A. Due to the formation of the second folded portion 30B, the size of the airbag 30 in the vertical direction becomes smaller than the stage after the deformation process to the intermediate form.

<The formation process of a 3rd folding part>
In this step, the lower portion 103 of the inflator assembly 20 is folded in the intermediate airbag 30 (see FIGS. 19A and 19B). At the time of this folding, a plurality of folding lines 109 extending linearly in the substantially vehicle width direction (left and right direction in FIG. 19B) are set for the lower portion 103.

  Here, prior to the setting of the folding line 109, as described above, the bellows-like folding from the front to the rear of the inflator assembly 20 of the airbag 30 in a flatly deployed state is performed from the front to the rear. The folded portion 101A is substantially orthogonal to the front-rear direction. Therefore, when the intermediate airbag 30 is in the storage configuration, setting the fold line 109 extending in the vehicle width direction with respect to the lower portion 103 of the airbag 30 means that the fold line extending in the other direction is set. It can be done more easily than setting.

  With the above setting of the fold line 109, the lower portion 103 is partitioned into a plurality of rectangular folding parts 103A. The interval between adjacent folding lines 109 is the folding width H2 when folding is performed. Then, the lower portion 103 is folded in a bellows along the folding lines 109 in order from the bottom to the top as indicated by the arrow D in FIG. 19B. In the present embodiment, among the plurality of folded parts 103A, only the lowermost part (shown by reference numeral 103A1) is folded in a direction different from the other parts (shown by reference numeral 103A2). The folding part 103A2 other than the lowermost part is folded downward while alternately changing the folding direction by a fixed width (folding width H2), whereas the lowermost folding part 103A1 is folded next to the folding part 103A1. Folded upward at the front end 103F of the portion 103A2. By the above folding, a third folding portion 30 </ b> C is formed below the inflator assembly 20.

  At this time, folding the lower portion 103 along the fold line 108 set so as to extend in the vehicle width direction with respect to the folded portion 103A substantially orthogonal to the front-rear direction follows the fold line extending in the other direction. It can be done more easily than folding.

  Each of the plurality of folded parts 103A is substantially orthogonal to the vertical direction. In other words, all the folded parts 103A are stacked (bundled) in the vertical direction.

Due to the formation of the third folded portion 30C, the vertical dimension of the airbag 30 becomes even smaller than the stage after the formation process of the second folded portion 30B.
In addition, among the above steps, the formation process of the second folding portion 30B and the formation step of the third folding portion 30C may be performed in the reverse order.

  Thus, by performing each process, the 1st-3rd folding parts 30A-30C in FIG. 17 are formed, and the airbag 30 is made into the accommodation form. The airbag module AM including the airbag 30 has a small size both in the front-rear direction and in the up-down direction, and is suitable for storage in the narrow storage portion 15 (see FIGS. 1 and 2).

  In the airbag module AM in the above-described storage form, the bolts 26 inserted into the respective parts of the airbag 30 (the first inflatable body 31, the second inflatable body 32, the inner bag 70, etc.) are inserted into the seat frame 16, The nut 17 is fastened to the bolt 26 so that the seat frame 16 is fixed.

The retainer 22 may be fixed to the vehicle (seat frame 16) by a member different from the bolt 26 described above.
The side airbag device includes an impact sensor 111 and a control device 112 shown in FIG. 1 in addition to the airbag module AM described above. The impact sensor 111 is composed of an acceleration sensor or the like, is attached to the body side portion 11 of the vehicle, and detects an impact applied to the body side portion 11 from the outside. The control device 112 controls the operation of the inflator 21 based on the detection signal from the impact sensor 111.

  As described above, the side airbag device of the present embodiment is configured. Next, the operation of the side airbag device will be described with reference to FIG. In FIG. 20, reference symbol A indicates a region (hereinafter referred to as “protection region A”) occupied between the occupant P and the body side portion 11 when the airbag 30 completes inflating and deploying.

  In this side airbag device, when no impact is applied to the vehicle from the side due to a side collision or the like, the airbag 30 is placed in a storage configuration and is continuously stored in the storage portion 15 together with the inflator assembly 20. At this time, the upper valve 80 and the lower valve 90 are both held in a flat state in which the fabric portions 81 and 91 on the vehicle interior and the fabric portions 82 and 92 on the vehicle exterior are in contact with each other (FIG. 15A, FIG. 16 (A)).

  On the other hand, when an impact of a predetermined value or more is applied to the body side portion 11 while the vehicle is traveling, and this is detected by the impact sensor 111, the control device 112 applies this to the inflator 21 based on the detection signal. An operation signal for operation is output. In response to this operation signal, in the inflator 21, as shown in FIGS. 5 and 6, the gas generating agent generates a high-temperature and high-pressure expansion gas G from the plurality of gas ejection holes 24 of the gas ejection section 23. It ejects in all directions in the direction (radial direction) orthogonal to the axis L1 of the inflator 21. Most of the inflation gas G is led out through the window 25 of the retainer 22 toward the front of the inner bag 70.

  Further, a part of the expansion gas G is led out downward of the lower expansion portion EL through the lower open end 22A of the retainer 22. That is, the gap between the portion of the retainer 22 different from the window portion 25 and the inflator 21 can serve as a passage for the expansion gas G from some of the gas ejection holes 24. Therefore, the expansion gas G ejected from the gas ejection holes 24 and hitting the retainer 22 changes its flow direction into two directions (substantially upward and substantially downward) along the axis L1 of the inflator 21. However, the portion of the inflator 21 above the gas ejection part 23 has a larger diameter than the gas ejection part 23, and the gap between the retainer 22 is between the gas ejection part 23 and the retainer 22. Smaller than the gap. For this reason, the expansion gas G whose flow direction has been changed hardly flows upward, and easily flows downward. Therefore, most of the expansion gas G whose direction of flow has been changed by hitting the retainer 22 as described above passes through the lower open end 22A of the retainer 22 and flows substantially downwardly in the lower valve 90 and It flows to the lower expansion part EL.

  As shown in at least one of FIGS. 7 and 12, the inner bag 70 starts to inflate due to the inflating gas G ejected to the inner bag 70 through the window portion 25 of the retainer 22. The inflated inner bag 70 inflates the outer central inflatable part EC. As the inner bag 70 is inflated, first, the rear half of the central inflating part EC (the part in which the inner bag 70 is located) is inflated. Next, due to the gas outflow from the intermediate opening OC, the entire central inflating part EC is inflated, and the thickness T1 of the airbag 30 in the vehicle width direction is larger than the thickness T2 when the inner bag 70 is inflated alone ( (See FIG. 3B). Here, FIG. 3B shows a cross-sectional structure along the line ZZ in FIG. 7 for the airbag module AM in which the inner bag 70 and the airbag 30 are inflated.

  When the inner bag 70 is inflated, the thickness of the airbag 30 in the vehicle width direction, that is, the thickness of the airbag 30 before the inflation gas G flows out from the intermediate opening OC is T1 ′. 'Is slightly larger than the thickness T2 and smaller than the thickness T1. And it is desirable to set this thickness T1 'to be smaller than the gap dimension (T3: see FIG. 3A) between the body side portion 11 and the vehicle seat 12. By such setting (T1 ′ <T3), the air bag 30 can be easily inserted into the gap between the body side portion 11 and the vehicle seat 12. A part of the inflation gas G in the inner bag 70 flows to the upper valve 80 through the upper opening OU.

  At this time, the expansion gas G has not yet flowed into the upper expansion portion EU, or has just flowed in slightly, and the internal pressure of the upper expansion portion EU is lower than the internal pressure of the central expansion portion EC. On the other hand, the inner pressure is high in the inner bag 70 into which the inflation gas G flows. Due to this internal pressure difference, in the upper valve 80, the force that separates the two fabric portions 81 and 82 is superior to the force that causes the approach. Therefore, as shown in FIG. 15 (B), both fabric parts 81 and 82 are separated from each other, and the entire upper valve 80 including the bendable part 88 has a cylindrical shape with its upper and lower ends open, and the expansion gas G is in the upper part. It flows through the flow path in the valve 80 to the upper expansion part EU.

  At this time, the expansion gas G has not yet flowed into the lower expansion portion EL, or has just flowed in slightly, and the internal pressure of the lower expansion portion EL is higher than the internal pressure of the central expansion portion EC. Low. On the other hand, the inner pressure is high in the inner bag 70 into which the inflation gas G flows. Therefore, due to this internal pressure difference, in the lower valve 90, as in the upper valve 80, as shown in FIG. 16B, the two fabric portions 91 and 92 are separated from each other, and the lower valve 90 including the bendable portion 98 The whole becomes a cylindrical shape with both upper and lower ends open, and the expansion gas G flows through the flow path in the lower valve 90 to the lower expansion portion EL.

  A part of the inflation gas G in the inflated inner bag 70 flows to the central inflation part EC through the intermediate opening OC. The expansion gas G flowing in this way causes the upper expansion unit EU, the lower expansion unit EL, and the central expansion unit EC to expand, and the folded state is canceled in the reverse order of the folded order. This is because the part that is folded later restricts the cancellation of the folded state of the part that is folded first.

  In the present embodiment in which the front-back folding for forming the second folding part 30B is performed after the folding from the front to the rear for the deformation to the intermediate form, in the storage form shown in FIG. In the airbag 30, the folded state of the second folded portion 30B is eliminated. At the time of the cancellation, the second folding unit 30B is accompanied by a rotation toward the front and the upper side with the folding line 108 as a fulcrum (see arrow E in FIG. 17). When the folded state is completely eliminated by this rotation, the second folded portion 30B becomes a state elongated in a substantially vertical direction.

  At this time, as described above, the central inflating portion EC (first folding portion 30A) of the airbag 30 located outside by the inflating inner bag 70 is inflated forward as indicated by a two-dot chain line in FIG. It is done. On the other hand, in the vicinity of the front of the central inflating part EC, a portion 106 (second folding part 30B) that is folded back forward and downward in the intermediate airbag 30 is located. For this reason, the folded portion 106 (second folding portion 30B) receives a forward force (pressing force F) by the central expansion portion EC (first folding portion 30A) that expands as described above. This pressing force F promotes the cancellation of the folded state of the folded portion 106 (rotation forward and upward with the folding line 108 as a fulcrum).

  In the present embodiment, the folding from the lower side to the upper side for forming the third folding part 30C is performed after the folding from the front side to the rear side for deformation to the intermediate form. Accordingly, the lower portion 103 (third folding portion 30C) of the inflator assembly 20 is deployed while canceling the folded state from the upper side to the lower side almost simultaneously with the cancellation of the folding (FIG. 17 and FIG. FIG. 20). Here, there is usually nothing in the vicinity of the lower portion of the storage portion 15 provided in the vicinity of the passenger P outside the vehicle that greatly hinders the downward deployment of the airbag 30 (see FIG. 4). Therefore, the lower portion 103 (third folding portion 30 </ b> C) of the airbag 30 can be easily deployed to a lower position below the storage portion 15. As a result of this deployment, the airbag 30 has a shape elongated in the substantially vertical direction as shown by the state (I) in FIG.

  At this time, in the lower portion 103 (third folding portion 30C), the plurality of folded portions 103A (103A1, 103A2) are substantially orthogonal to the vertical direction. Therefore, the lower portion 103 (third folding portion 30C) of the airbag 30 that has received the pressure of the inflation gas G in the folded portion 103A is deployed straight downward while eliminating the folded state. (The direction of arrow J in FIG. 20: the lower side). As described above, since the straightness of the downward deployment is good, the airbag 30 is easily deployed to a lower position below the storage unit 15.

  Further, during the unfolding, the folded portion 103A1 is accompanied by rotation downward (see arrow H in FIG. 17) with the front end 103F of the adjacent folded portion 103A2 as a fulcrum. When there is an interference such as luggage on the vehicle seat 12, the direction of the rotation is a direction away from the interference. Therefore, the possibility that the folded portion 103A1 hits the interference object when the folded state 103A1 is released is strongly pressed because the folded portion 103A1 is folded upward at the rear end of the folded portion 103A2 and overlapped on the upper side. It becomes lower than the case where the rotation toward the front and lower is accompanied at the time of deployment.

  The airbag 30 elongated in the substantially vertical direction has the inflator storage portion 39 left in the storage portion 15 of the seat back 14, and continues to be shown in the states (II) and (III) of FIG. It expands between the side part 11 and the vehicle seat 12 while eliminating the folded state toward the front (direction of arrow K in FIG. 20: front side). While the airbag 30 is inflated and deployed, that is, before the airbag 30 is completely inflated and deployed, the inflation and deployment of the inner bag 70 is completed. When the inner bag 70 has been inflated and deployed, its front end 70F is positioned behind the front end ECF of the central inflatable portion EC in the airbag 30 in the inflated and deployed state and ahead of the front end 14F of the seat back 14. In other words, almost the rear half of the central inflatable part EC is inflated (see FIG. 7), and the inner bag 70 is positioned at least near the side of the occupant P such as the chest PT. In this respect, the inner bag 70 is different from an inner tube that does not normally inflate near the side of the occupant P. Therefore, the inner bag 70 also exhibits the function of restraining the passenger P and protecting it from impact.

  When the airbag 30 is inflated and deployed, as shown in at least one of FIGS. 3A and 4, the upper inflatable portion EU is provided on the body side portion 11 and the shoulder of the occupant P seated on the vehicle seat 12. Inflate and deploy with the part PS. The central inflating part EC is inflated and deployed between the body side part 11 and the chest PT of the occupant P, and the lower inflating part EL is inflated and deployed between the body side part 11 and the waist part PP of the occupant P. . Certain inflatable parts do not inflate and deploy extremely slowly than other inflatable parts. In particular, since the inflating and deploying of the central inflating part EC is ensured by the inflating of the inner bag 70, unlike the Patent Document 2, the central inflating part EC does not inflate and deploy extremely slowly compared to other inflating parts. On the contrary, the central inflating part EC does not inflate and expand extremely rapidly. Then, the airbag 30 is deployed so as to occupy the entire protection area A (see FIG. 20) in the vicinity of the occupant P outside the vehicle, so that each part of the occupant P corresponds to the corresponding inflatable portions EU, EC, Restrained by the EL, the occupant P is reliably protected from the impact caused by the side collision.

Here, as shown in FIG. 12, the flow passage area SC of the intermediate opening OC is set smaller than the flow passage area SU of the upper opening OU (SC <SU). Thus, the flow rate per unit time of the expansion gas G flowing to the central expansion portion EC is smaller than the flow rate per unit time of the expansion gas G flowing to the upper expansion portion EU through the upper opening OU. Further, since the flow area SC of the intermediate opening OC is set smaller than the flow area SL of the lower opening OL (SC <SL), the expansion flowing to the central expansion portion EC through the intermediate opening OC. The flow rate per unit time of the working gas G is smaller than the flow rate per unit time of the expansion gas G flowing through the lower opening OL to the lower expansion portion EL. Therefore, the remaining part of the central inflating part EC shown in FIG. 4 (in other words, the part where the inner bag 70 does not exist ) inflates and develops later than the upper inflating part EU and slower than the lower inflating part EL. Along with this, the internal pressure of the central inflating part EC rises later than the internal pressure of the upper inflating part EU and the internal pressure of the lower inflating part EL. Is lower than any of the internal pressures of the upper expansion part EU and the lower expansion part EL. As a result, the shoulder portion PS having high impact resistance among the side portions of the occupant P is restrained and protected by the upper inflating portion EU having high internal pressure, and the waist portion PP having high impact resistance is restrained by the lower inflating portion EL having high internal pressure. And protected. Further, the chest PT having low impact resistance is softly constrained and protected by the central expansion portion EC having low internal pressure.

  When the airbag 30 is inflated and deployed, the lower portion 113 of the airbag 30 in the state (I) of FIG. 20 is a narrow gap between the body side portion 11 and the waist portion PP, thigh portion PF, etc. of the occupant P. It will expand forward through G1 (see FIG. 3A). This gap G1 is generally narrower than the gap G1 between the other part of the occupant P and the body side portion 11. However, the airbag 30 in the storage form is easier to push the occupant P inward in the vehicle width direction than when the airbag 30 is first deployed from the rear to the front and then deployed from the top to the bottom (hereinafter referred to as a comparative example). In the comparative example, the occupant P is pressed against the seat cushion 13 or the like when the airbag 30 is about to enter the narrow gap G1, whereas in the present embodiment, the airbag 30 once deployed to a low position is used. This is because the occupant P is not pressed against the vehicle seat 12 or the like when the lower portion 113 is deployed forward. Therefore, the airbag 30 has a narrow gap between the occupant P and the body side part 11 while pushing the waist part PP, thigh part PF, etc. of the occupant P inward in the vehicle width direction to widen the gap G1 at the lower part 113 thereof. Securely deploy forward through G1.

  At this time, in the front portion 101 of the inflatable assembly 30 of the airbag 30 for storage, the plurality of folded portions 101A are substantially orthogonal to the front-rear direction. Therefore, after the lower portion 103 is expanded downward, the front portion 101 of the airbag 30 that has received the pressure of the inflation gas G in the folded portion 101A is straightened forward while eliminating the folded state. expand. Thus, since the straightness of the deployment toward the front is good, the airbag 30 can be easily deployed to a more forward position.

  After the ejection period of the inflation gas G in the inflator 21 or after the ejection is stopped, the lower valve 90 is caused to approach both fabric parts 91 and 92 due to an internal pressure difference generated between the lower expansion part EL and the central expansion part EC. The power to separate is better. Therefore, as shown in FIG. 16C, the bendable portion 98 of the lower valve 90 is closed and bent. The bent bendable portion 98 closes the flow path in the lower valve 90, and the expansion gas G once flowing into the lower expansion portion EL flows through the lower valve 90 to the central expansion portion EC (backflows). ) Is regulated. Therefore, the internal pressure of the lower expansion portion EL, which has been increased to an appropriate internal pressure to protect the occupant P's lower back portion PP, does not decrease due to the backflow of the expansion gas G to the central expansion portion EC and becomes an appropriate value. Maintained.

  As shown in FIG. 15C, the upper valve 80 operates (closes) similarly to the lower valve 90. The expansion gas G once flowing into the upper expansion section EU is restricted from flowing (backflowing) to the central expansion section EC through the upper valve 80. Therefore, the internal pressure of the upper expansion part EU, which has been increased to an internal pressure appropriate to protect the shoulder part PS of the occupant P, does not decrease due to the backflow of the expansion gas G to the central expansion part EC, and is an appropriate value. Maintained.

  Further, when the body side portion 11 enters the vehicle due to the impact at the time of the side collision and the expanded central expansion portion EC is pressed against the chest PT of the occupant P or the like, the upper valve 80 is connected to the upper expansion portion EU. While exhibiting the pressure regulation mechanism which adjusts an internal pressure, the lower valve 90 exhibits the pressure regulation function which adjusts the internal pressure of the lower expansion part EL. The contents of these pressure adjusting functions are the same in both the upper valve 80 and the lower valve 90.

  The upper valve 80 allows the expansion gas G to flow from the central expansion portion EC to the upper expansion portion EU, but restricts the expansion gas G from flowing (backflowing) from the upper expansion portion EU to the central expansion portion EC. To do. More specifically, when the internal pressure of the central expansion part EC is higher than the internal pressure of the upper expansion part EU, the entire upper valve 80 including the bendable part 88 opens both upper and lower ends as shown in FIG. The cylinder is opened (opened), and the flow of the expansion gas G from the central expansion portion EC to the upper expansion portion EU is allowed. When the internal pressure of the upper expansion part EU is higher than the internal pressure of the central expansion part EC, the bendable part 88 of the upper valve 80 is closed and bent as shown in FIG. By the bent portion 88, the flow path in the upper valve 80 is closed, and the expansion gas G is restricted from flowing (backflowing) from the upper expansion portion EU to the central expansion portion EC. As described above, the expansion gas G in the central expansion portion EC flows to the upper expansion portion EU and the backflow is restricted, so that the internal pressure of the central expansion portion EC is reduced and the internal pressure of the upper expansion portion EU is reduced. To rise. Therefore, it is difficult for the internal pressure of the central inflating part EC to rise excessively when restraining the chest PT or the like.

  In particular, in the present embodiment, the inflation gas G only flows through the inner bag 70 and the upper valve 80 between the central inflation portion EC and the upper inflation portion EU, and the central inflation portion without passing through the upper valve 80. The expansion gas G does not flow between the EC and the upper expansion unit EU. Therefore, the pressure regulating function of the upper valve 80 is not impaired due to the flow of the expansion gas G.

  Further, as described above, the impact resistance of the shoulder portion PS of the occupant P is higher than the impact resistance of the chest PT or the like. Therefore, there is no problem even if the internal pressure of the upper expansion part EU increases due to the expansion gas G from the central expansion part EC. Rather, the occupant P is pushed to the inside of the vehicle through the shoulder part PS by the upper expansion part EU. The passenger P is more reliably protected from the impact.

  Further, since the lower valve 90 operates with respect to the lower expansion portion EL in the same manner as the upper valve 80, the occupant P is pushed to the vehicle inner side through the waist portion PP having high impact resistance by the lower expansion portion EL. The occupant P is more reliably protected from impact.

According to the embodiment described in detail above, the following effects can be obtained.
(1) An inner bag 70 that encloses the inflator assembly 20 is provided in the central inflating part EC of the airbag 30. Further, the inner bag 70 communicates with the upper inflating part EU through the upper opening OU, communicates with the central inflating part EC through the intermediate part opening OC, and communicates with the lower inflating part EL through the lower opening OL (FIG. 7). Therefore, a specific inflating part (central inflating part EC) is inflated with other inflating parts (upper inflating part EU and EU) while inflating and deploying each inflating part EU, EC, EL with an internal pressure corresponding to the impact resistance of the part of passenger P The deployment performance of the airbag 30 can be improved by suppressing the inflation and deployment extremely later than the lower inflation portion EL).

  Further, the inner bag 70 is disposed such that the front end 70F thereof is positioned behind the front end ECF of the central inflatable portion EC in the inflated and deployed airbag 30 and ahead of the front end 14F of the seat back 14. (Fig. 7). Therefore, the inner bag 70 can also exhibit the function of restraining the occupant P and protecting it from impact, and the restraint / protection performance can be improved as compared with the case where the occupant P is restrained and protected by the airbag 30 alone. be able to.

  (2) The flow passage area SC of the intermediate opening OC is different (reduced) from the flow passage areas SU and SL of the upper opening OU and the lower opening OL (FIG. 12). Therefore, it is possible to inflate and deploy the inflatable portion corresponding to the portion having high impact resistance among the side portions of the occupant P with high internal pressure, and to inflate and deploy the inflatable portion corresponding to the portion having low impact resistance to low internal pressure. Become.

  (3) An upper valve 80 that allows only the flow of the inflation gas G from the inner bag 70 to the upper inflation portion EU is provided in the vicinity of the upper opening OU in the upper inflation portion EU (FIG. 13). Therefore, without restraining the phenomenon in which the internal pressure of the central inflating part EC excessively rises when the occupant P is restrained, the internal pressure of the upper inflating part EU that has been increased to an appropriate internal pressure to protect the occupant P is not reduced. Can be maintained.

  (4) By making the central expansion part EC and the upper expansion part EU independent from each other, the flow of the expansion gas G between the central expansion part EC and the upper expansion part EU is performed only through the upper valve 80. . Therefore, the expansion gas G is restricted from flowing between the central expansion portion EC and the upper expansion portion EU without passing through the upper valve 80, and the pressure regulation function of the upper valve 80 is impaired due to the distribution. Thus, the effect (3) can be further ensured.

  (5) A lower valve 90 that allows only the flow of the inflation gas G from the inner bag 70 to the lower inflation portion EL is provided in the vicinity of the lower opening OL in the lower inflation portion EL (FIG. 14). Therefore, while suppressing the phenomenon in which the internal pressure of the central inflating portion EC excessively increases when the occupant P is restrained, the internal pressure of the lower inflating portion EL that has been increased to an appropriate internal pressure to protect the occupant P can be reduced. Can be maintained.

  (6) By making the central expansion portion EC and the lower expansion portion EL independent from each other, the flow of the expansion gas G between the central expansion portion EC and the lower expansion portion EL is performed only through the lower valve 90. . Therefore, the expansion gas G is restricted from flowing between the central expansion part EC and the lower expansion part EL without passing through the lower valve 90, and the pressure adjustment function of the lower valve 90 is impaired due to the distribution. Thus, the effect (5) can be further ensured.

  (7) The central inflatable part EC is inflated and deployed in the vicinity of the side of the occupant P, such as the chest PT, the upper inflatable part EU is inflated and deployed in the vicinity of the side of the shoulder PS of the occupant P, and the lower inflated part EL Inflate and deploy in the vicinity of the side of the waist portion PP of the occupant P (FIGS. 3A and 4). Therefore, the chest PT and the like are restrained and protected by the inflated and deployed central inflatable part EC, the shoulder PS is restrained and protected by the inflated and deployed upper inflatable part EU, and the waist PP is restrained and protected by the inflated and deployed lower inflating part EL. can do.

  (8) Although related to (2) above, the flow area SC of the intermediate opening OC in the inner bag 70 is set smaller than the flow area SU of the upper opening OU (FIG. 12). Therefore, at the initial stage of inflation of the airbag 30, the internal pressure of the central inflatable portion EC can be made lower than the internal pressure of the upper inflatable portion EU. It is possible to restrain and protect the chest PT or the like having low impact resistance by the high upper inflating part EU, and to softly restrain and protect the breast PT or the like having low impact resistance by the central inflating part EC having low internal pressure.

  (9) Although related to (2) above, the flow area SC of the intermediate opening OC in the inner bag 70 is set smaller than the flow area SL of the lower opening OL (FIG. 12). Therefore, at the initial stage of inflation of the airbag 30, the internal pressure of the central inflatable portion EC can be made lower than the internal pressure of the lower inflatable portion EL, and the waist portion PP having high impact resistance among the side portions of the occupant P has a high internal pressure. It is possible to restrain and protect the chest PT or the like having low impact resistance by the lower inflating portion EL, and to softly restrain and protect the chest PT or the like having low impact resistance by the central inflating portion EC having low internal pressure.

  (10) When the airbag 30 is stored (FIG. 17), the front portion 101 of the airbag 30 in the deployed state is folded from the front to the rear (FIG. 18). An intermediate form (see FIGS. 19A and 19B) elongated in the vertical direction. Further, the upper portion 102 of the intermediate-type airbag 30 than the inflator 21 is folded forward and downward to be positioned in front of the inner bag 70 (see FIG. 17). Therefore, the airbag 30 can be made compact in both the front-rear direction and the up-down direction, and can be easily stored even in the narrow storage portion 15. Further, by pressing the folded portion 106 by the central inflating portion EC that is inflated as the inner bag 70 is inflated, it is possible to promote the elimination of the folded state of the portion (FIG. 20).

  (11) At least a part of the folded portion 106 of the airbag 30 in the intermediate form is positioned below the boundary 107 between the central inflating part EC and the upper inflating part EU (FIG. 17). Therefore, the folded portion 106 is positioned on the front side of the central inflating portion EC and the inner bag 70, and the pressing force F by the inflating inner bag 70 and the central inflating portion EC is applied to the portion 106 with certainty. The state can be resolved.

  (12) The lower portion 103 of the intermediate airbag 30 of the airbag 30 is folded in a bellows shape from below to above so that the folded portions 103A1, 103A2 are substantially orthogonal to the vertical direction. (FIGS. 19A and 19B). Therefore, the airbag 30 can be made into a compact storage form (FIG. 17) suitable for storage in the narrow storage portion 15.

  Further, at the time of a side collision of the vehicle, as shown in FIG. 20, after the lower portion 103 is deployed to a lower position below the storage portion 15 than the inflator assembly 20 of the storage-type airbag 30, the airbag 30. The whole can be expanded forward. Thus, the occupant P can be protected from an impact caused by a side collision by the airbag 30 deployed over the wide protection region A in the vicinity of the occupant P outside the vehicle.

  (13) When the airbag 30 is in the intermediate configuration (FIGS. 19A and 19B), the front portion 101 of the inflator assembly 20 of the deployed airbag 30 is folded as shown in FIG. The portion 101A is folded in a bellows shape from the front to the rear so as to be substantially orthogonal to the front-rear direction. Therefore, the airbag 30 elongated in the vertical direction due to the downward deployment of the lower portion 103 and the cancellation of the folding of the upper portion 102 can be deployed straight forward while eliminating the folded state. Thus, since the straightness of the deployment toward the front is improved, the airbag 30 can be reliably deployed to a more forward position.

  (14) In addition to the configuration of (13) above, the bellows-like folds extending from the lower side to the upper side of the lower portion 103 of the intermediate airbag 30 extend in the vehicle width direction as shown in FIG. This is performed along a plurality of folding lines 109. Accordingly, when the airbag 30 of the intermediate configuration (FIGS. 19A and 19B) is to be stored (FIG. 17), the width of the airbag 30 relative to the lower portion 103 of the airbag 30 of the intermediate configuration is reduced. Setting the extending fold line 109 is easier than setting a fold line extending in another direction. Further, it is possible to easily fold the lower portion 103 of the airbag 30 in a bellows shape from the lower side to the upper side along the folding lines 109. In this way, both unfolding performance and folding performance can be achieved.

  (15) The gap G1 between the waist part PP of the occupant P and the body side part 11 is generally narrower than the gap G1 between other parts of the occupant P and the body side part 11. Therefore, in the case of the airbag 30 having the waist protection part, it is inherently difficult to deploy the waist protection part between the waist part PP and the body side part 11. In this regard, in the present embodiment, the first and third folding portions 30A and 30C are provided for the airbag 30 having the lower inflating portion EL. For this reason, the lower inflating portion EL can be deployed in a narrow gap G1 between the waist portion PP of the occupant P and the body side portion 11 in a state where the lower inflating portion EL is deployed to a lower position below the storage portion 15, and the waist portion PP is appropriately A great effect of protecting is obtained.

  (16) Generally, in the case of the airbag 30 partitioned into a plurality of inflatable portions in the vertical direction, the lower inflatable portion is pulled toward the inflatable portion side that inflates adjacent to the upper side. Therefore, in order to reliably protect the waist portion PP of the occupant P from impact by the airbag 30, it is important to deploy the lowermost inflatable portion forward at a lower position.

  Therefore, as in this embodiment, in the side airbag device in which the airbag 30 is partitioned into three in the vertical direction to provide the upper inflation unit EU, the central inflation unit EC, and the lower inflation unit EL, the lower inflation unit EL A particularly great effect can be obtained by deploying the airbag 30 to a lower position below the storage portion 15 and further deploying the airbag 30 forward in that state. That is, it is assumed that the lower expansion portion EL is pulled upward by the expansion of the central expansion portion EC adjacent to the upper side by expanding the lower portion of the lower expansion portion EL in the narrow gap G1 between the waist portion PP and the body side portion 11. In addition, the occupant P, particularly the waist PP, can be appropriately protected.

  (17) When the lower portion 103 of the intermediate airbag 30 of the airbag 30 is folded, as shown in FIGS. 17 and 20, the lowermost folding portion 103A1 is replaced with the folding portion 103A2 adjacent thereto. The front end 103F is folded upward and overlapped with the folded portion 103A2. For this reason, when the folded portion 103A1 is released from the folded state, the possibility that the folded portion 103A1 hits the interference on the vehicle seat 12 and pushes it strongly is folded back at the rear end of the folded portion 103A2 and overlapped on the upper side. In this case, it can be made lower than the case accompanied by rotation toward the front and lower side.

Note that the present invention can be embodied in another embodiment described below.
<Matters related to inflator assembly 20>
-As the retainer 22, you may use the thing by which the upper end part was obstruct | occluded and only the lower end part was open | released, and the upper and lower both ends opened | released together.

The inflator 21 may be directly attached to the seat back 14 without using the retainer 22.
-An inner tube may be arrange | positioned in the rear part inside the inner bag 70, and the inflator assembly 20 may be arrange | positioned in this inner tube. This inner tube is used to rectify the expansion gas G ejected from the inflator 21.

  As the inner tube, for example, one having a structure shown in FIGS. 21A and 21B can be adopted. The inner tube 116 includes a tubular portion 117 that extends in the vertical direction and is open at both upper and lower ends, and a sheet-like portion 118 that extends upward from the upper end on the vehicle inner side of the tubular portion 117. The lower part of the tubular part 117 is formed so that the diameter becomes smaller (the diameter is reduced) toward the lower side. In forming the inner tube 116, a single fabric 119 having an inverted L-shape is used as shown in FIG. In the fabric 119, a bolt hole 121 is formed at an upper portion of a portion that is to become the sheet-like portion 118. Further, a bolt hole 122 is also formed at a place to be the tubular portion 117. And the inner tube 116 which consists of the said tubular part 117 and the sheet-like part 118 is formed by the lower end part of the said fabric 119 being rounded tubular, and also the both ends of the lower end part being stitched | sutured. Reference numerals 123 in FIGS. 21A and 21B and FIG. 22 indicate stitched portions. The vertical dimension of the tubular portion 117 is set to a size that can substantially cover the window portion 25 of the retainer 22.

  At least the lower end portion of the tubular portion 117 is disposed inside the lower valve 90. The tubular portion 117 may be coupled to the inner bag 70 and the airbag 30 (the first inflatable body 31 and the second inflatable body 32) by means such as sewing. And the lower part of the inflator assembly 20 is arrange | positioned in the tubular part 117 (FIG. 21 (A)), and a pair of upper and lower volt | bolts 26 of the retainer 22 are penetrated by the corresponding bolt holes 121 and 122. FIG. Both bolts 26 are inserted into the seat frame 16 and the nut 17 is tightened, whereby the inner tube 116 is fixed to the seat frame 16 together with the inner bag 70 and the airbag 30.

  When the inner tube 116 having the above-described configuration is employed, the expansion gas G ejected from the gas ejection portion 23 of the inflator 21 and passed through the window portion 25 hits the tubular portion 117, and the flow direction is a direction along the axis L <b> 1 of the inflator 21 (up and down Direction). Here, since the diameter of the lower portion of the tubular portion 117 is reduced toward the lower side, the expansion gas G tends to flow upward rather than downward. Therefore, compared with the case where the inner tube 116 is not used, the expansion gas G can be rectified in a desired direction.

<Matters related to airbag 30>
As described above, when the airbag 30 is placed in the storage configuration, the upper portion 102 of the intermediate airbag 30 is folded forward and downward and positioned in front of the inner bag 70. In addition to or in place of this, the lower portion 103 of the intermediate airbag 30 relative to the inflator assembly 20 may be folded back forward and upward to be positioned in front of the inner bag 70.

  When folding the lower portion 103 of the intermediate airbag 30, the lowermost folded portion 103A1 is folded back at the rear end of the next folded portion 103A2 so as to overlap the lower side of the folded portion 103A2. May be. Also in this case, the same effect as in the above-described embodiment in which the lowermost folded portion 103A1 is folded back at the front end 103F of the adjacent folded portion 103A2 and overlapped on the folded portion 103A2 can be expected.

The front portion 101 of the airbag 30 in the deployed state relative to the inflator assembly 20 may be folded from the front to the rear in a folding manner different from the bellows folding.
<Matters related to inner bag 70>
-You may change the position of the intermediate part opening OC in the inner bag 70 in the up-down direction.

  Condition (I), that is, “the front end 70F of the inner bag 70 is positioned behind the front end ECF of the central inflating part EC in the airbag 30 in the inflated and deployed state and ahead of the front end 14F of the seat back 14”. The shape of the inner bag 70 may be changed within a range that satisfies the above. An example is shown in FIG. In this example, the front end edge 71 of the inner bag 70 is inclined so as to become lower toward the front side. The upper end of the front end edge 71 is located in the vicinity of the closing part 57, and the lower end is located in the lower part of the outer edge of the central expansion part EC. This lower end corresponds to the front end 70F of the inner bag 70. In addition, as long as this condition (I) is satisfied, the intermediate portion opening OC may be disposed so as to be positioned at the foremost side.

  The position of the upper end of the front end edge 71 is substantially the same as that of the inner bag 70 of the embodiment, whereas the lower end (front end 70F) is positioned considerably forward of the inner bag 70 of the embodiment. Therefore, when it changes in this way, the capacity | capacitance of the inner bag 70 will become larger than the said embodiment, and the restraint and protection performance of the passenger | crew P by the inner bag 70 will become high.

  The intermediate part opening OC opens toward the front of the central inflating part EC where the inner bag 70 is not disposed, and here, obliquely forward and upward. In FIG. 23, the intermediate opening OC is provided in the vicinity of the upper end of the front end edge 71 of the inner bag 70 (front end 70 </ b> F), but may be provided above this.

  As described above, when the front end edge 71 of the inner bag 70 is inclined and the intermediate opening OC is provided in the front end edge 71, the following advantages are also obtained. That is, the front-rear position of the intermediate opening OC in the central expansion part EC can be easily changed. When the front-rear position of the intermediate opening OC changes, the timing at which the inflation gas G passes through the intermediate opening OC of the inner bag 70 also changes. Correspondingly, the timing of expansion and deployment of the central expansion part EC also changes. In other words, the timing at which the central inflating part EC inflates and expands can be easily changed by adjusting the front and rear positions of the intermediate part opening OC.

-The position of the front end 70F of the inner bag 70 in the front-rear direction may be changed within a range that satisfies the above condition (I).
The flow area of each opening may be set so that at least one of the upper opening OU, the lower opening OL, and the intermediate opening OC has a different flow area from the other openings. In this case, for the opening communicating with the inflating portion that restrains and protects the high impact resistance portion of the occupant P, the flow passage area is set large, and conversely, the expansion that restrains and protects the low impact resistance portion. For the opening communicating with the part, it is desirable to set the flow channel area small. Accordingly, in the above embodiment, the flow passage areas are set to be approximately the same in the upper opening OU and the lower opening OL, but the flow passage areas may be different.

A plurality of at least one of the upper opening OU, the intermediate opening OC, and the lower opening OL may be provided in the inner bag 70.
In the above embodiment, the intermediate opening OC is provided at the front edge 71 of the inner bag 70. However, the intermediate opening OC may be provided on the side surface of the inner bag 70.

The inner bag 70 may be one in which a single fabric is folded in two and joined in a bag shape by means such as stitching, like the first inflatable body 31 and the second inflatable body 32.
<Matters related to the upper valve 80 and the lower valve 90>
The upper valve 80 only needs to be able to restrict the expansion gas G in the upper expansion portion EU from flowing (reversely flowing) to the central expansion portion EC, and has a structure different from that of the above embodiment. Also good. Similarly, the lower valve 90 only needs to be able to restrict the expansion gas G in the lower expansion portion EL from flowing (backflowing) to the central expansion portion EC, and has a structure different from that of the above embodiment. There may be.

-At least one of the upper valve 80 and the lower valve 90 may be omitted.
<Other matters>
-At least one of the peripheral coupling portions 37, 45, the lower coupling portions 54, 55, the upper coupling portion 56, the inner coupling portions 58, 59, 74, 75, the partition coupling portion 61, and the coupling portions 76, 83, 93, You may form by means different from the said sewing, for example, adhesion | attachment using an adhesive agent.

The storage portion 15 may be replaced with the seat back 14 and may be provided in the body side portion 11 at a location near the vehicle exterior of the occupant P seated on the vehicle seat 12.
In the present invention, the upper inflating part EU is used as an inflating part for protecting a part different from the shoulder part PS of the occupant P, or the central inflating part EC is provided for protecting a part different from the chest PT of the occupant P. The present invention can also be applied to a side airbag device in which an inflatable portion is used or the lower inflatable portion EL is an inflatable portion for protecting a portion different from the waist portion PP of the occupant P.

The side view which shows the vehicle seat equipped with the side airbag apparatus with the passenger | crew in one Embodiment which actualized this invention. FIG. 3 is a cross-sectional plan view showing a positional relationship between a vehicle seat, an occupant, and a body side part. FIG. 7A is a front sectional view showing the positional relationship between the vehicle seat, the occupant, and the body side part, and FIG. 7B shows the airbag module in which the inner bag and the airbag are in an inflated state. Sectional drawing which shows the cross-section along a line. The side view which shows the airbag module by which the airbag was made into the flat deployment state with a passenger | crew. FIG. 5 is a side view showing an inflator assembly disposed in the airbag of FIG. 4. The top view which shows the state which looked at the inflator assembly of FIG. 5 from diagonally backward upper direction with a seat frame, a nut, an airbag, etc. FIG. Sectional drawing which shows the internal structure of an airbag module when a seat back stands substantially vertically. Sectional drawing which shows each vehicle inner side part of the 1st expansion body and 2nd expansion body in FIG. 7 in the state isolate | separated to the up-down direction. The expanded view which shows the state which expand | deployed the 2nd expansion body etc. planarly. The expanded view which shows the state which expand | deployed the 1st expansion body etc. planarly. (A) is a fragmentary sectional view which shows the state of the tether when the airbag is not inflated, and (B) is a fragmentary sectional view which shows the state of the tether when the airbag is inflated. Explanatory drawing which shows the positional relationship of the fabric part inside a vehicle in an inner bag, and an upper valve and a lower valve. Sectional drawing which expands and shows the X section in FIG. Sectional drawing which expands and shows the Y section in FIG. (A)-(C) are the fragmentary sectional views explaining the effect | action of an upper valve. (A)-(C) are the fragmentary sectional views explaining the effect | action of a lower valve. The side view which shows the airbag module made into the form for storage. The side view which shows the relationship between the airbag of a plane expansion | deployment state, and a fold line. (A) is a schematic side view which shows an airbag module when an airbag is folded by the intermediate form, (B) is a schematic back view which shows the airbag module of (A). Explanatory drawing which shows a mode that the airbag of a storage form expand | swells and expands with a protection area | region. (A) is a front view which shows another example which arrange | positions an inflator assembly in an inner tube, (B) is a perspective view of the inner tube. The expanded view which shows the state which expand | deployed the inner tube in planar shape. It is a figure which shows the other example in which the inner bag in which the front end edge inclined was used, and is sectional drawing which shows the internal structure of an airbag module corresponding to FIG.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 11 ... Body side part, 12 ... Vehicle seat, 14 ... Seat back, 14F, 70F, 103F, ECF ... Front end, 21 ... Inflator, 30 ... Air bag, 70 ... Inner bag, 80 ... Upper valve, 90 ... Lower valve , 101 ... front part, 102 ... upper part, 106 ... folded part, 107 ... boundary part, EC ... central expansion part, EL ... lower expansion part, EU ... upper expansion part, G ... expansion gas, OC ... intermediate Part opening, OL ... lower opening, OU ... upper opening, P ... occupant, PP ... waist, PS ... shoulder, PT ... chest, SC, SL, SU ... channel area.

Claims (11)

An inflator is enclosed in the rear part of the inflator, and the airbag that has been stored by folding is stored in the vicinity of the outside of the passenger seated on the vehicle seat, and the inflator is removed from the inflator in response to an impact from the side of the vehicle. In the side airbag device in which the airbag is inflated and deployed toward the front of the vehicle between the vehicle body side portion and the vehicle seat by the jetted inflation gas,
The airbag is partitioned into a central inflating portion, an upper inflating portion on the upper side of the central inflating portion, and a lower inflating portion on the lower side of the central inflating portion,
In the central inflatable portion, an inner bag containing the inflator is provided,
The inner fabric constituting the inner bag is coupled to the inner fabric constituting the airbag, and the outer fabric constituting the inner bag is coupled to the outer fabric constituting the airbag,
One of the partition part of the central expansion part and the upper expansion part and the partition part of the central expansion part and the lower expansion part is partitioned by coupling, and the other is partitioned by stitching,
The section defined by the stitching is formed by co-sewing the inner fabric and outer fabric of the inner bag and the inner fabric and outer fabric of the airbag in the vehicle front-rear direction.
The inner bag communicates with the upper inflating portion through an upper opening provided on the upper side of the inner bag, and communicates with the lower inflating portion through a lower opening provided on the lower side of the inner bag. It is communicated with the central inflating part through an intermediate opening provided in the inner bag,
In the state where the airbag is inflated and deployed, the inner bag is positioned such that the front end of the inner bag is located behind the front end of the central inflating portion and ahead of the front end of the seat back in the vehicle seat. A side airbag device characterized by being arranged. 2. The side airbag device according to claim 1, wherein at least one of the upper opening, the lower opening, and the intermediate opening has a flow path area different from other openings. The side air according to claim 1 or 2, wherein an upper valve that allows only the flow of the inflation gas from the inner bag to the upper inflation portion is provided in the vicinity of the upper opening in the upper inflation portion. Bag device. The central expansion portion and the upper expansion portion are formed independently from each other, and the flow of the expansion gas between the central expansion portion and the upper expansion portion is performed only through the upper valve. The side airbag device as described. The lower valve which permits only the distribution | circulation of the gas for the said expansion | swelling to the said lower expansion part from the said inner bag is provided in the vicinity of the said lower opening in the said lower expansion part. The side airbag device described in 1. 6. The central expansion portion and the lower expansion portion are formed independently of each other, and the flow of the expansion gas between the central expansion portion and the lower expansion portion is performed only through the lower valve. The side airbag device as described. The central inflating part is inflated and deployed in the vicinity of the side of the chest of the occupant, the upper inflating part is inflated and deployed in the vicinity of the side of the shoulder of the occupant, and the lower inflating part is in the vicinity of the side of the waist of the occupant. The side airbag device according to any one of claims 1 to 6, wherein the side airbag device is inflated and deployed. The side airbag device according to claim 7, wherein a flow path area of the intermediate opening in the inner bag is set smaller than a flow path area of the upper opening. The side airbag device according to claim 7 or 8, wherein a channel area of the intermediate opening in the inner bag is set smaller than a channel area of the lower opening. The airbag in the storage form has an intermediate form elongated in a substantially vertical direction by folding a front portion of the inflated airbag from the front toward the rear, and further, the airbag in the intermediate form is further folded. The side airbag device according to any one of claims 1 to 9, wherein the side airbag device is formed by folding an upper portion of the bag from the inflator forward and downward to be positioned in front of the inner bag. The side airbag device according to claim 10, wherein at least a part of the folded portion of the airbag in the intermediate form is positioned below a boundary portion between the central inflating portion and the upper inflating portion.

Images