JP7001018B2 - Airbag - Google Patents

Description

The present invention relates to an airbag that inflows an expansion gas into the interior to expand and protect an occupant seated in a vehicle seat.

Conventionally, as an airbag, as an airbag for a steering wheel, an inner bag portion is provided inside the main bag portion, and a rectifying member in which the expansion gas discharged from the inflator is arranged inside the inner bag portion is provided. After that, there was a structure in which the bag was allowed to flow into the main bag section and the inner bag section (see, for example, Patent Document 1). Further, in this conventional airbag, the expansion gas flowing into the inner bag portion is suppressed from flowing out to the bag body side by the check valve, and when the expansion of the main bag portion is completed, the inner bag is suppressed. By keeping the internal pressure of the part high, the occupant protection performance was improved.

JP-A-2015-3675

However, in the conventional airbag, since a rectifying member that allows expansion gas to flow is also provided inside the inner bag portion on the main bag portion side, the bag is tentatively expanded before the expansion of the main bag portion is completed. When an occupant comes into contact with the inner bag portion, the expansion gas flows out from the rectifying member arranged in the inner bag portion to the main bag portion side, which reduces the substantial volume of the inner bag portion. , The occupant cannot be accurately received by the inner bag part.

The present invention solves the above-mentioned problems, and provides an airbag capable of accurately receiving an occupant by an inflated inner bag portion even when the occupant is received before the expansion is completed. The purpose.

The airbag according to the present invention is configured to be configured to be able to protect an occupant seated in a vehicle seat by inflowing an expansion gas into the airbag and inflating the airbag.
A occupant side wall portion arranged on the occupant side when expansion is completed, a vehicle body side wall portion arranged on the vehicle body side, and an inflow opening opened to allow expansion gas to flow into the vehicle body side wall portion. An airbag having a configuration in which a mounting portion arranged on the periphery of the inflow opening and fixed to a mounting site is arranged.
The airbag is provided with a main bag portion having a vent hole that constitutes an outer peripheral wall when expansion is completed and exhausts excess expansion gas, and an inner bag portion that expands inside the main bag portion.
The inner bag portion is provided with an inflow opening and a mounting portion together with the main bag portion, and is an upstream side to the main bag portion side in the flow of expansion gas flowing in through the inflow opening. It has an outflow hole that allows the expansion gas to flow out to the side, and is configured to be supported by the peripheral edge of the mounting site when expansion is completed.
The outflow hole portion is closed when the inflow amount of the expansion gas from the inflow opening is reduced, and the outflow of the expansion gas to the main bag portion side is restricted.

In the airbag of the present invention, the inner bag portion that expands in the main bag portion is arranged so as to be on the upstream side of the flow of the expansion gas that flows in through the inflow opening, and is used for expansion toward the main bag portion. Since it is configured to have an outflow hole for gas to flow out, even if the airbag comes into contact with the occupant before the expansion of the main bag is completed, the expansion is completed quickly. The inner bag section can accurately protect the occupants.

Therefore, in the airbag of the present invention, even when the occupant is received before the expansion is completed, the occupant can be accurately received by the inflated inner bag portion.

Further, in the airbag of the present invention, the outflow hole portion that causes the expansion gas that has flowed into the inner bag portion to flow out to the main bag portion side is closed when the inflow amount of the expansion gas from the inflow opening decreases. Since the configuration is such that the outflow of expansion gas to the main bag section is restricted, the expansion gas that has flowed into the inner bag section is restricted from flowing out to the main bag section after the expansion of the airbag is completed. Therefore, the inner bag portion can be kept in a high internal pressure state after the expansion is completed. Further, this inner bag portion is configured to be supported by the peripheral edge of the mounting portion when the expansion of the airbag is completed, and when the main bag portion that has completed expansion receives the occupant, the inner bag portion exerts internal pressure. Since it is supported by the peripheral edge of the mounting site while being held high, for example, even when the occupant moving forward is restrained at a position deviated from the center in the main bag portion, it is supported by the peripheral edge of the mounting site. The tightly inflated inner bag portion can regulate the large movement of the main bag portion, and the main bag portion can accurately protect the occupant.

Specifically, in the airbag of the present invention, the outflow hole portion is formed by cutting out the peripheral wall constituting the inner bag portion, and the outflow opening is closed from the inside of the inner bag portion. It is preferable to have a configuration including a member.

More specifically, in the airbag having the above configuration, the inner bag portion has a vehicle body side panel having an inflow opening and a mounting hole, and a occupant side panel having an outer shape substantially the same as the vehicle body side panel. Then, the outer peripheral edges of the vehicle body side panel and the occupant side panel are connected to each other to form a bag shape, and the external shape of the vehicle body side panel and the occupant side panel is abbreviated between the vehicle body side panel and the occupant side panel. The configuration is such that the partition panels that are set to be the same and are connected to the outer peripheral edge of the vehicle body side panel and the occupant side panel are arranged so as to cover substantially the entire circumference.
As a configuration in which a communication hole for communicating the occupant side panel side and the vehicle body side panel side is formed in the partition panel, and a cover portion capable of closing the opening is arranged.
An outflow opening is formed near the outer peripheral edge of the vehicle body side panel.
It is preferable to set the total opening area of the vent hole to be smaller than the total opening area of the outflow opening.

In an airbag having such a configuration, when the expansion gas flows into the inside of the inner bag portion through the inflow opening at the initial stage of expansion, the inner bag portion first expands between the partition panel and the occupant side panel. In a state where the partition panel is in contact with the occupant side panel so as to allow the gas to flow in, the expansion gas is expanded while flowing out from the outflow opening of the outflow hole portion to the main bag portion side. Then, when the main bag portion completes the expansion and the inflow amount of the expansion gas from the inflow opening decreases, the expansion gas filled between the partition panel and the vehicle body side panel in the inner bag portion becomes. , It will move between the compartment panel and the occupant side panel through the communication hole provided in the compartment panel, in other words, the compartment panel will move toward the vehicle body side panel side. Therefore, the moved partition panel closes the outflow opening and regulates the outflow of the expansion gas from the inside bag portion. Further, in the airbag having the above configuration, since the outflow opening is set so that the total opening area is larger than the total opening area of the vent hole formed in the main bag portion, the main bag portion is surplus. While appropriately exhausting the expansion gas, it expands while maintaining an appropriate internal pressure. Since the outflow opening for allowing the expansion gas to flow out to the main bag portion side is formed at a position near the outer peripheral edge of the vehicle body side panel in the inner bag portion, the inner bag portion is formed from the outflow opening. The influence of the outflow of the expansion gas can be suppressed as much as possible, and when the expansion is completed, it can be accurately supported by the peripheral edge of the mounting site. Further, in the airbag having the above configuration, the occupant side panel, the partition panel, and the vehicle body side panel are overlapped and the outer peripheral edges are connected to each other to form an inner bag portion having an outflow hole portion. The inner bag part can be easily manufactured.

Furthermore, when the airbag is mounted on the steering wheel of the vehicle, the expansion completed shape seen from the vertical side of the main bag portion is made into a substantially disk shape that can cover the upper surface of the handle almost entirely.
It is preferable that the inner bag portion is configured so that the expansion completed shape seen from the vertical direction side is provided with a region protruding outward at least in the front-rear direction from the steering wheel in the state of straight-ahead steering.

If the airbag has the above configuration, the inner bag portion is mainly supported by a wide area supported by at least the left and right parts of the handle when the expansion is completed. When the bag portion receives the occupant and moves, the inner peripheral surface side of the main bag portion is supported by the outer peripheral surface side of the high-pressure inner bag portion, thereby suppressing the swing of the main bag portion. be able to. Therefore, when the occupant is received, the occupant can be accurately protected by the main bag portion that suppresses the swing.

Specifically, in the state of straight-ahead steering, the steering wheel is set so that the distance from the center of the front part of the steering wheel during steering is smaller than the distance of the part on the left-right direction from the center. When mounted on the steering wheel, the expansion complete shape seen from the vertical side of the inner bag part can cover the front side part of the steering wheel during straight-ahead steering, and it protrudes forward from the arrangement area of the inflow opening on both the left and right sides. If it is configured as a substantially semi-elliptical shape that expands, a part of the inner bag portion that has completed expansion can be supported by the front part of the handle, and even if it is configured to be mounted on a deformed handle. The main bag portion can accurately protect the driver as a occupant.

Furthermore, in the state of straight-ahead steering, the distance from the center of the front part and the part on the rear side is set to be smaller than the distance from the center of the part on the left-right direction side. Even in this case, the expansion complete shape seen from the vertical side of the inner bag part can be covered with the front side part and the rear side part of the steering wheel during straight-ahead steering, and spreads from the arrangement area of the inflow opening to both front and rear sides. If configured as a substantially rectangular shape, the front end side and the rear end side of the inner bag portion that has completed expansion can be supported by the front side portion and the rear end portion of the handle, and the configuration is mounted on the irregular handle. Even so, the main bag portion can accurately protect the driver as a occupant.

It is a schematic plan view which shows the airbag device for a handle using the airbag which is one Embodiment of this invention. It is a schematic vertical sectional view when the airbag device for a steering wheel of FIG. 1 is mounted on a vehicle. It is a bottom view of the airbag used for the airbag device for a steering wheel of FIG. 1 in a flat unfolded state. It is a bottom view of the inner bag part used in the airbag of FIG. 3 in a flat unfolded state. It is a top view which shows the base cloth which constitutes the airbag of FIG. FIG. 3 is a schematic vertical sectional view showing a process of expansion of an airbag in the airbag device for a steering wheel according to the embodiment. It is a schematic plan view which shows the airbag device for a handle using the airbag which is another embodiment of this invention. FIG. 7 is a schematic vertical sectional view showing a state in which the airbag has completed expansion in the airbag device for a steering wheel of FIG. 7. It is a schematic plan view which shows the airbag apparatus for a handle using the airbag which is still another embodiment of this invention. 9 is a schematic vertical sectional view showing a state in which the airbag has completed expansion in the airbag device for a steering wheel of FIG. 9.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings. In the embodiment, the airbag 20 for the steering wheel is taken as an example and described. The airbag 20 is used in a steering wheel airbag device (hereinafter abbreviated as "airbag device") M mounted on the steering wheel W as shown in FIGS. 1 and 2. The handle W includes a handle body 1 and an airbag device M arranged above the boss portion B in the center of the handle body 1. In the case of the embodiment, the handle body 1 connects the ring portion R to be gripped at the time of steering, the boss portion B arranged substantially in the center of the ring portion R and connected to the shaft SS, and the boss portion B and the ring portion R. It is provided with four spoke portions S and the like. The handle W of the embodiment is a modified handle. Specifically, in the steering wheel W, the ring portion R is configured to have operation grip portions HL and HR on both the left and right sides in the straight-ahead steering state, and the front side portion RF during straight-ahead steering is viewed from the vertical direction side in the left-right direction. It is said to be a straight line roughly along the line. Then, the front side portion RF (the front side portion of the steering wheel W) sets the separation distance DF from the center C (shaft SS) at the time of steering, and the separation distance DL, DR from the center C (shaft SS) of the operation grip portions HL and HR. Is set smaller than (see FIG. 1).

In the embodiment, the front-back, up-down, and left-right directions are based on the straight-ahead steering of the handle W mounted on the vehicle unless otherwise specified, and the shaft of the shaft SS (see FIG. 2) to which the handle W is assembled is used as a reference. The vertical direction along the direction is the vertical direction, the front-rear direction of the vehicle which is the axis orthogonal direction of the shaft SS is the front-rear direction, and the left-right direction of the vehicle which is the axis orthogonal direction of the shaft SS is the left-right direction. It shows.

As shown in FIGS. 1 and 2, the handle body 1 is arranged so as to connect each portion of the ring portion R, the boss portion B, and the spoke portion S, and includes a core metal 3 made of a metal such as an aluminum alloy. There is. A coating layer 5 made of synthetic resin is coated on the portion of the ring portion R in the core metal 3 and the portion on the ring portion R side in each spoke portion S. Further, a steel boss 4 for inserting the shaft SS and fixing the nut N is arranged at the portion of the boss portion B in the core metal 3. Further, a lower cover 6 made of synthetic resin that covers the lower part of the boss portion B is arranged at the lower portion of the handle body 1.

As shown in FIG. 1, the airbag device M is arranged at the boss portion B at the center of the left and right sides of the handle W, and the airbag 20 to be folded and stored and the airbag 20 are charged with an expansion gas. To attach the supplied inflator 11, the case 12 that houses and holds the airbag 20 and the inflator 11, the airbag cover 14 that covers the folded airbag 20, and the airbag 20 and the inflator 11 to the case 12. It is equipped with a retainer 10 and.

As shown in FIG. 2, the inflator 11 includes a substantially cylindrical main body portion 11a having a plurality of gas discharge ports 11b, and a flange portion 11c for attaching the inflator 11 to the case 12. The flange portion 11c is formed with a through hole (not shown) for passing each bolt (not shown) of the retainer 10.

As shown in FIG. 2, the case 12 is made of sheet metal and has a substantially rectangular plate-shaped bottom wall portion 12a to which the inflator 11 is inserted and attached from below, and a peripheral wall portion 12b extending vertically from the outer peripheral edge of the bottom wall portion 12a. , Is equipped. A mounting piece 12c extending outward is formed at the upper end of the peripheral wall portion 12b (see FIG. 1), and a mounting board of a horn switch mechanism (not shown) is mounted on the mounting piece 12c. Then, using this mounting board (not shown), the case 12 is mounted and fixed to the core metal 3 of the handle W, and the airbag device M is mounted on the upper part of the boss portion B of the handle body 1 already mounted on the shaft SS. The Rukoto. Further, a side wall portion 14c of the airbag cover 14 is attached to the peripheral wall portion 12b of the case 12 by using a rivet 15 or the like (see FIG. 2). In the case of the embodiment, the airbag 20 and the inflator 11 use a bolt (not shown) of the retainer 10 arranged in the airbag 20 as a mounting means, and use the bolt (not shown) of the inflow openings 26 and 34 in the airbag 20. It is attached to the bottom wall portion 12a of the case 12 by penetrating the peripheral mounting holes 27a and 35a, the bottom wall portion 12a of the case 12, and the flange portion 11c of the inflator 11 and fixing them with nuts (not shown). ..

The airbag cover 14 is made of synthetic resin and has a ceiling wall portion 14a that covers the upper part of the airbag 20 housed in the case 12 and a side wall portion 14c having a substantially square cylinder shape that extends downward from the vicinity of the outer peripheral edge of the ceiling wall portion 14a. And have. The ceiling wall portion 14a is formed with two door portions 14b, 14b that are pushed by the inflatable airbag 20 and open back and forth.

The airbag 20 includes a main bag portion 21 that constitutes an outer peripheral wall when expansion is completed, and an inner bag portion 32 that expands inside the main bag portion 21.

The main bag portion 21 includes an occupant side wall portion 21a arranged on the driver MD side as a occupant when expansion is completed, and a vehicle body side wall portion 21b arranged on the handle W side as a vehicle body. In the embodiment, as shown in FIGS. 3 and 5, the main bag portion 21 connects the outer peripheral edges 23a and 24a of the substantially circular occupant side panel 23 and the vehicle body side panel 24 having substantially the same outer shape to each other. As shown in the two-dot chain line in FIGS. 1 and 2 and B in FIG. 6, the expansion completed shape is laterally formed as a bag-like shape that can cover the entire ring portion R when viewed from above. It is configured to be substantially elliptical and spherical when viewed from the viewpoint. An inflow opening 26 for inflowing the expansion gas G is formed in the substantially center of the vehicle body side wall portion 21b (vehicle body side panel 24) of the main bag portion 21 by opening in a circular shape. The inflow opening 26 is for inserting the main body portion 11a of the inflator 11 from below, and the peripheral edge of the inflow opening 26 has a mounting portion 27a having a mounting hole 27a through which a bolt (not shown) of the retainer 10 is inserted. It is said that. The mounting portion 27 is mounted on the bottom wall portion 12a of the case 12 as a mounting portion by the retainer 10 together with the mounting portion 35 described later of the inner bag portion 32. Further, a vent hole 29 for exhausting excess expansion gas is formed on the vehicle body side wall portion 21b side (vehicle body side panel 24 side) of the main bag portion 21. In the case of the embodiment, the vent hole 29 is positioned in front of the inner bag portion 32 in a state where the airbag 20 is spread flat, and is opened in a circular shape at two locations that are substantially symmetrical. Is formed (see FIG. 3). Further, each vent hole 29 has an inner diameter dimension D1 set smaller than the inner diameter dimension D2 of the outflow opening 43 formed in the inner bag portion 32 (see FIGS. 3 and 4).

The inner bag portion 32 expands in the main bag portion 21, and the shape at the time of completion of expansion is a substantially circular shape smaller than that of the main bag portion 21 when viewed from above. Specifically, the inner bag portion 32 has an outer diameter dimension at the time of completion of expansion, which is substantially the same as the ring diameter of the ring portion R in the handle W (see FIG. 1).

The inner bag portion 32 includes an occupant side wall portion 32a arranged on the driver MD side when expansion is completed, a vehicle body side wall portion 32b arranged on the handle W side, and an occupant side wall portion 32a side and a vehicle body side wall portion arranged inside. A partition wall portion 32c that separates the 32b side is provided (see FIG. 4), and as shown in FIG. 6, the retainer 10 is used to fasten the bottom of the case 12 together with the main bag portion 21. It is configured to be mounted and fixed to the wall portion 12a. That is, the vehicle body side wall portion 32b of the inner bag portion 32 is composed of an inflow opening 34 into which the main body portion 11a of the inflator 11 is inserted from below and a peripheral portion of the inflow opening 34, similarly to the main bag portion 21. A mounting portion 35 having a mounting hole 35a through which a bolt (not shown) of the retainer 10 is inserted is formed (see FIG. 4).

As shown in FIGS. It has a occupant-side panel 37 which is formed to have substantially the same circular shape as the occupant side wall portion 32a, and has a bag shape by connecting the outer peripheral edges 37a and 38a of the vehicle body-side panel 38 and the occupant-side panel 37 to each other. In addition, the partition panel 39 constituting the partition wall portion 32c is arranged between the vehicle body side panel 38 and the occupant side panel 37. The outer peripheral shape of the partition panel 39 is set to substantially the same circular shape as the vehicle body side panel 38 and the occupant side panel 37, and the outer peripheral edge 39a is set to substantially the entire circumference of the vehicle body side panel 38 and the occupant side panel 37. It is coupled to 38a to partition the inside of the inner bag portion 32.

Further, the inner bag portion 32 is provided with an outflow hole portion 42 for allowing the expansion gas to flow out to the main bag portion 21 side. The outflow hole portion 42 has an outflow opening 43 formed by cutting out a vehicle body side panel 38 (vehicle body side wall portion 32b) and a cover portion 44 (a cover portion 44 capable of closing the outflow opening 43 from the inside of the inner bag portion 32). Cover member) and (see FIGS. 4 and 5). The outflow opening 43 is formed by opening in a circular shape at two locations that are substantially symmetrical in the vicinity of the leading edge in the vicinity of the outer peripheral edge 38a of the vehicle body side panel 38. As described above, each of the outflow openings 43 has an inner diameter dimension D2 set to be larger than the inner diameter dimension D1 of the vent hole 29. In the embodiment, two outflow openings 43 and two vent holes 29 are arranged. Then, in the embodiment, by setting the inner diameter dimension D2 of each outflow opening 43 to be larger than the inner diameter dimension D1 of each vent hole 29, the vent hole 29 sets the total opening area to the opening area of the outflow opening 43. It is set smaller than the total. As shown in FIG. 5, the cover portion 44 (cover member) is composed of a partition wall portion 32c (partition panel 39). Specifically, the cover portion 44 (cover member) is composed of an area in the partition wall portion 32c (partition panel 39) in which the communication hole 46, which will be described later, is not arranged, and has an inner bag for the outflow opening 43. It is configured so that it can be covered over the entire surface from the inside of the portion 32.

As shown in FIG. 5, the partition wall portion 32c (compartment panel 39) has a communication hole for communicating the occupant side wall portion 32a side (occupant side panel 37 side) and the vehicle body side wall portion 32b side (vehicle body side panel 38 side). 46 are formed. In the case of the embodiment, the communication holes 46 are formed so as to be interspersed with a large number of small-diameter openings (9 in the case of the embodiment). In the partition panel 39, the region near the outer peripheral edge 39a covers the outflow opening 43 when the expansion of the airbag 20 is completed, and this region constitutes the cover portion 44. In the airbag 20 of the embodiment, as described above, the inner bag portion 32 has a substantially circular shape when the expansion completed shape is viewed from the vertical direction side, and the outer diameter dimension is substantially the same as the ring diameter in the ring portion R. Therefore, when the expansion is completed, it is supported by the peripheral edge of the mounting portion (in the case of the embodiment, the ring portion R of the handle W) (see B in FIG. 6).

In the airbag 20 of the embodiment, the occupant side panel 23 and the vehicle body side panel 24 constituting the main bag portion 21 and the occupant side panel 37, the vehicle body side panel 38, and the partition panel 39 constituting the inner bag portion 32 are Each is composed of a flexible woven fabric made of polyamide yarn, polyester, or the like.

The airbag device M of the embodiment can be mounted on a vehicle as follows. First, the airbag 20 is folded so as to be able to be stored in the case 12 in a state where the retainer 10 is arranged in the inner bag portion 32 by projecting bolts (not shown) from the mounting holes 27a and 35a. After that, the folded airbag 20 is housed in the case 12, the main body portion 11a of the inflator 11 is inserted from below, and the inflator 11 and air are used by using bolts and nuts (not shown) protruding from the bottom wall portion 12a. Attach to bag 20 and case 12. Further, if the case 12 is covered with the airbag cover 14, the airbag cover 14 is attached to the case 12 by using the rivet 15 or the like, and then the horn switch mechanism (not shown) is attached to the attachment piece 12c of the case 12. The airbag device M can be assembled. The airbag device M can be mounted on the vehicle V by mounting the airbag device M on the handle body 1 previously fastened to the shaft SS by using a mounting board (not shown) of the horn switch mechanism.

In the airbag device M of the embodiment, if the expansion gas G is discharged from the gas discharge port 11b of the inflator 11, the airbag 20 inflows the expansion gas into the inside and expands, and the door of the airbag cover 14 is expanded. The portions 14b and 14b are pushed open and protruded from the case 12 to complete the expansion so as to cover substantially the entire upper surface of the handle W as shown by the two-dot chain line in FIGS. 1 and 2 and B in FIG. Become.

Specifically, in the airbag 20 of the embodiment, the expansion gas G discharged from the inflator 11 first flows into the inner bag portion 32 from the inflow opening 34, so that the inner bag portion 32 The expansion gas G flows into the inside to expand, and the main bag portion 21 causes the expansion gas G to flow into the inside to expand through the outflow opening 43 of the outflow hole portion 42 formed in the inner bag portion 32. Will be done. At this time, the partition panel 39 (compartment wall portion 32c) arranged in the inner bag portion 32 is pressed by the expansion gas G flowing into the inside from the inflow opening 34 as shown in A of FIG. The inner bag portion 32 comes into contact with the occupant side panel 37 (occupant side wall portion 32a), and the inner bag portion 32 causes the expansion gas to flow between the partition panel 39 and the vehicle body side panel 38 so that the vehicle body side panel 38 (the vehicle body side panel 38 ( The expansion gas G is expanded from the outflow opening 43 of the outflow hole 42 formed in the side wall portion 32b) to the main bag portion 21 side. Then, when the main bag portion 21 substantially completes the expansion and the inflow amount of the expansion gas G from the inflow opening 34 decreases, the inside of the inner bag portion 32 is between the partition panel 39 and the vehicle body side panel 38. The filled expansion gas moves between the partition panel 39 (compartment wall portion 32c) and the occupant side panel 37 (occupant side wall portion 32a) through the communication hole 46 provided in the partition panel 39. In other words, the partition panel 39 moves toward the vehicle body side panel 38, and the moved partition panel 39 closes the outflow opening 43 and comes from inside the inner bag portion 32. The outflow of expansion gas will be regulated (see B in FIG. 6). Then, the airbag 20 completes the expansion in a state where the outflow of the expansion gas G from the inside bag portion 32 is restricted.

In the airbag 20 used in the airbag device M of the embodiment, the inner bag portion 32 that expands in the main bag portion 21 is on the upstream side of the flow of the expansion gas G that flows in through the inflow opening 34. Since the airbag 20 is provided with an outflow hole 42 for allowing the expansion gas G to flow out to the main bag 21 side, it is assumed that the airbag 20 is provided before the expansion of the main bag 21 is completed. Even if the bag comes into contact with the driver MD as a occupant, the inner bag portion 32 that quickly completes the expansion can accurately protect the driver MD.

Therefore, in the airbag 20 of the embodiment, even when the driver MD as a occupant is received before the expansion is completed, the inflated inner bag portion 32 can accurately receive the driver MD.

Further, in the airbag 20 of the embodiment, the outflow hole portion 42 that causes the expansion gas G that has flowed into the inner bag portion 32 to flow out to the main bag portion 21 side is the inflow amount of the expansion gas G from the inflow opening 34. Since the configuration is such that the expansion gas G is blocked and the outflow of the expansion gas G to the main bag portion 21 side is restricted when the amount of the expansion gas G decreases, the expansion gas G flowing into the inner bag portion 32 expands the air bag 20. After the completion, the outflow to the main bag portion 21 side is restricted, and the inner bag portion 32 can be kept in a high internal pressure state after the expansion is completed. Further, the inner bag portion 32 is configured to be supported by the ring portion R of the handle W which is the peripheral edge of the mounting portion when the expansion of the airbag 20 is completed, and the driver is supported by the main bag portion 21 which has completed the expansion. When receiving the MD, the inner bag portion 32 is supported by the peripheral edge of the mounting portion (ring portion R of the handle W) while the internal pressure is kept high. Therefore, for example, in the case of a diagonal collision or an offset collision of a vehicle in which a occupant (driver MD) enters later than in a head-on collision, the driver MD that moves forward so as to move diagonally forward is used as the main bag. Even when restrained at a position deviated from the center of the portion 21, the main bag portion 21 is greatly expanded by the inner bag portion 32 that is firmly expanded so as to be supported by the peripheral edge of the mounting portion (ring portion R of the handle W). The movement can be restricted, and the driver MD can be accurately protected by the main bag portion 21. In particular, in the airbag 20 of the embodiment, the inner bag portion 32 has an outer diameter smaller than that of the main bag portion 21 at the time of completion of expansion, and has an outer diameter dimension substantially equal to the ring diameter of the ring portion R. Since it has a substantially disk shape, it is possible to accurately protect the driver MD when restraining the driver MD at a position slightly shifted to the left and right from the main bag portion 21.

Further, in the airbag 20 of the embodiment, the inner bag portion 32 is outside the vehicle body side panel 38 and the occupant side panel 37, and the partition panel 39 arranged between the vehicle body side panel 38 and the occupant side panel 37. By connecting the peripheral edges 37a, 38a, 39a to each other, the space between them is formed into a bag shape partitioned by the partition panel 39. Therefore, at the initial stage of expansion of the airbag 20, the inner bag portion 32 passes through the inflow opening 34. When the expansion gas G flows into the inside of the bag, the inner bag portion 32 first causes the expansion gas to flow between the partition panel 39 and the vehicle body side panel 38, and the partition panel 39 is combined with the occupant side panel 37. In the state of being in contact with each other, the expansion gas G is discharged from the outflow opening 43 of the outflow hole portion 42 to the main bag portion 21 side while expanding. Then, when the main bag portion 21 completes the expansion and the inflow amount of the expansion gas G from the inflow opening 26 decreases (the discharge of the expansion gas from the inflator 11 is completed), the inside of the inner bag portion 32 In, the expansion gas G filled between the partition panel 39 and the vehicle body side panel 38 passes between the partition panel 39 and the occupant side panel 37 via the communication hole 46 provided in the partition panel 39. In other words, the compartment panel 39 moves toward the vehicle body side panel 38, and the moved compartment panel 39 closes the outflow opening 43 and enters the inner bag 32. It will regulate the outflow of expansion gas G from. At this time, in the airbag 20 of the embodiment, since the communication holes 46 are scattered in large numbers as small diameters, the entire partition panel 39 can be smoothly moved toward the vehicle body side panel 38 side, and the communication holes 46 can be smoothly moved toward the vehicle body side panel 38 side. As shown in B of FIG. 6, the moved partition panel 39 makes it possible to cover the outer peripheral surface of the inflator 11 without gaps. Further, in the airbag 20 of the embodiment, since the outflow opening 43 is set so that the total opening area is larger than the total opening area of the vent hole 29 formed in the main bag portion 21, the main bag is set. The unit 21 expands while maintaining an appropriate internal pressure while appropriately exhausting the excess expansion gas G. Since the outflow opening 43 for flowing the expansion gas G to the main bag portion 21 side is formed in the inner bag portion 32 at a position near the outer peripheral edge 38a of the vehicle body side panel 38, the inner bag portion is formed. The 32 can be accurately supported by the peripheral edge of the mounting portion (ring portion R in the case of the embodiment) when the expansion is completed by suppressing the influence of the outflow of the expansion gas G from the outflow opening 43 as much as possible. Further, in the airbag 20 of the embodiment, the inner peripheral edge 37a, 38a, 39a is connected to each other by overlapping the occupant side panel 37, the partition panel 39, and the vehicle body side panel 38, so that the inner having the outflow hole portion 42 is provided. Since the bag portion 32 is configured, the inner bag portion 32 can be easily manufactured.

Furthermore, in the airbag 20 of the embodiment, the inner bag portion 32 has a substantially circular shape obtained when the expansion is completed when viewed from the vertical direction side, which is substantially the same as the ring diameter of the ring portion R. The vicinity of the outer peripheral edge of the ring portion R is supported by the ring portion R except for the front region. In particular, the steering wheel W on which the airbag 20 of the embodiment is mounted is a modified handle, and has a distance DF from the center of the front portion RF, which is formed in a linear shape substantially along the left-right direction during straight-ahead steering. , The separation distance from the center of the left-right side portion (operation grip portion HL, HR) is set smaller than DL and DR. That is, the steering wheel W is provided with a ring portion R having a shape such that the front region is cut out during straight-ahead steering. The inner bag portion 32 has a substantially circular expansion completed shape as seen from the vertical direction side, and the front side portion 32d is a linear shape substantially along the left and right direction when viewed from the vertical direction side during straight-ahead steering in the ring portion R. Since the configuration is such that the front side portion RF is projected forward from the front side portion RF, the front side portion 32d of the inner bag portion 32 that has completed expansion can be accurately supported by the front side portion RF in the ring portion R. (See B in FIG. 6).

Further, in the airbag 20 of the embodiment, if the inner bag portion 32 has an area supported by the front portion side (front portion RF) of the handle W at least by the left and right portions of the handle W when the expansion is completed. Since it is supported by a wide area, when the main bag portion 21 receives and moves the driver MD as a occupant, the inner peripheral surface side of the main bag portion 21 is the outer peripheral surface of the high-pressure inner bag portion 32. Since it is supported by the side, the swing of the main bag portion 21 can be suppressed. Therefore, the driver MD can be accurately protected by the main bag portion 21 in which the swing is suppressed when the occupant is received.

In the embodiment, an airbag 20 including an inner bag portion 32 having a substantially circular outer shape when viewed from the vertical direction is taken as an example, but the outer shape of the inner bag portion is circular. The configuration is not limited, and for example, the airbags 20A and 20B shown in FIGS. 7 and 9 may be configured.

Similar to the above-mentioned airbag 20, the airbag 20A shown in FIG. 7 has a front portion RF that is substantially linear along the left-right direction when viewed from the vertical direction side during straight-ahead steering. It is mounted on a handle W having a ring portion R having a shape such that a front region is cut out. In the airbag 20A, the inner bag portion 50 that expands in the main bag portion 21 can cover the front side portion RF in the ring portion R during straight-ahead steering so that the expansion complete shape seen from the vertical direction side can be covered with an inflow (not shown). It is configured as a substantially semi-elliptical shape so as to project forward from the central portion 50a having the opening and spread to both the left and right sides. The inner bag portion 50 has the same configuration as the inner bag portion 32 in the above-mentioned airbag 20 except for the expansion completed shape, and detailed description thereof will be omitted. Specifically, as shown in FIGS. 7 and 8, the inner bag portion 50 is arranged so as to project forward from the central side portion 50a, and the front side portion 50b that covers the front side portion RF of the ring portion R when the expansion is completed. And, in this front side portion 50b, the left end portion 50c and the right end portion 50d, which are on the left and right end sides when the expansion is completed, are respectively configured to be located near the outer peripheral edge of the main bag portion 21 when the expansion is completed. , The expansion complete shape is made to be substantially symmetrical. The anterior portion 50b is configured so that the leading edge at the completion of expansion is positioned in front of the anterior portion RF of the ring portion R (see FIG. 7). That is, in this airbag 20A, the inner bag portion 50 has a configuration capable of covering substantially the entire upper surface of the front side portion RF in the ring portion R. Therefore, even when the airbag 20A having such a configuration is used, a part of the inner bag portion 50 (front side portion 50b) that has completed expansion can be supported by the front side portion RF in the ring portion R. The main bag portion 21 can accurately protect the driver even if the steering wheel is mounted on the irregularly shaped handle. In particular, in this airbag 20A, the front side portion 50b of the inner bag portion 50 covers almost the entire upper surface of the front side portion RF, and the left end portion 50c and the right end portion 50d are outside the main bag portion 21 when the expansion is completed. Since it is configured to be located near the peripheral edge and is arranged so as to extend to the left and right outward from the front side portion RF when viewed from the vertical direction side, it is tentatively before the expansion of the main bag portion 21 is completed. Even if the airbag 20A comes into contact with the driver, the inner bag portion 50 that quickly completes the expansion accurately protects the driver who moves forward while tilting the upper body forward. Can be done.

The airbag 20B shown in FIG. 9 is mounted on the handle WB. In the steering wheel WB, as shown in FIG. 9, the ring portion Rb has operation grip portions HL and HR on both the left and right sides in the straight-ahead steering state, and has a front side portion RF during straight-ahead steering and a rear side during straight-ahead steering. Each of the portion RB and the portion RB has a linear shape substantially along the left-right direction when viewed from the up-down direction side. Similar to the front portion RF, the rear portion RB also sets the separation distance DB from the center C (shaft SS) at the time of steering from the separation distance DL and DR from the center C (shaft SS) of the operation grip portions HL and HR. Is also set small. That is, like the airbag 20 described above, the airbag 20B travels straight so as to have an anterior portion RF and a rear portion RB that are substantially linear along the left-right direction when viewed from the vertical direction side during straight-ahead steering. The front region and the rear region at the time of steering are mounted on a handle WB having a ring portion Rb having a notched shape, respectively.

In this airbag 20B, as shown in FIG. 9, the inner bag portion 55 that expands in the main bag portion 21 has an expansion completed shape seen from the vertical direction side with the front side portion RF in the ring portion R during straight-ahead steering. It is configured as a substantially rectangular shape so as to cover the posterior portion RB and extend from the central portion 55a having an inflow opening (not shown) to both front and rear sides. The inner bag portion 55 has the same configuration as the inner bag portion 32 in the above-mentioned airbag 20 except for the expansion completed shape, and detailed description thereof will be omitted. Specifically, as shown in FIGS. 9 and 10, the inner bag portion 55 is arranged so as to project forward from the central side portion 55a, and when the expansion is completed, the inner bag portion 55 and the front side portion 55b covering the front side portion RF of the ring portion Rb. , A rear portion 55c that is arranged so as to project rearward from the central portion 55a and covers the rear portion RB of the ring portion Rb when the expansion is completed, and the expansion completion shape is made substantially symmetrical. ing. The anterior portion 55b is configured so that the leading edge at the completion of expansion is located in front of the anterior portion RF of the ring portion Rb, and the posterior portion 55c has the trailing edge at the time of completion of expansion of the ring portion Rb. It is configured to be located posterior to the posterior site RB. Further, the inner bag portion 55 is configured so that the width dimension on the left-right direction side when the expansion is completed is substantially the same as the length dimension (left-right width dimension) of the rear side portion RB in the ring portion Rb. There is. That is, in this airbag 20B, the inner bag portion 55 has a configuration capable of covering substantially the entire upper surface of the front side portion RF and the rear side portion RB in the ring portion Rb. Therefore, even when the airbag 20B having such a configuration is used, a part of the inner bag portion 55 (front side portion 55b, rear side portion 55c) that has completed expansion is replaced with the front side portion RF and the rear portion in the ring portion R. It can be supported by the side portion RB, and even if it is mounted on a deformed handle, the main bag portion 21 can accurately protect the driver. In particular, in this airbag 20A, since the inner bag portion 55 is configured to expand widely in the front-rear direction, the airbag 20B comes into contact with the driver before the expansion of the main bag portion 21 is completed. However, the inner bag portion 55, which quickly completes the expansion so as to cover the steering wheel WB widely in the front-rear direction, can accurately protect the upper body of the driver.

In the embodiment, the airbags 20, 20A and 20B are mounted on the handles W and WB having the ring portions R and Rb which are not annular, but of course, the airbag of the present invention has an annular ring. It may be mounted on a handle having a portion. Further, the airbag of the present invention may be mounted on a steering wheel having a ring portion and having grip portions on both the left and right sides in a straight-ahead steering state. Further, the present invention is not limited to the airbag for the steering wheel, and for example, the airbag for the passenger seat for protecting the occupant seated in the passenger seat by being folded and stored in front of the passenger seat. , The present invention is applicable. When the present invention is applied to an airbag for a passenger seat, the inner bag portion is supported by an instrument panel or the like constituting the peripheral edge of the mounting portion.

20, 20A, 20B ... Airbag, 21 ... Main bag part, 26 ... Inflow opening, 27 ... Mounting part, 29 ... Vent hole, 32 ... Inner bag part, 32d ... Front part, 34 ... Inflow opening, 35 ... Mounting part, 37 ... occupant side panel, 37a ... outer peripheral edge, 38 ... vehicle body side panel, 38a ... outer peripheral edge, 39 ... partition panel, 39a ... outer peripheral edge, 42 ... outflow hole part, 43 ... outflow opening, 44 ... cover Part (cover member), 46 ... Communication hole, 50 ... Inner bag part, 50a ... Central part, 50b ... Front part, 55 ... Inner bag part, 55a ... Central part, 55b ... Front part, 55c ... Rear part , G ... Expansion gas, W, WB ... Handle, R, Rb ... Ring part, RF ... Front side part, RB ... Rear part, M ... Airbag device for handle.

Claims (4)

It is configured to allow expansion gas to flow inside and expand to protect the occupants seated in the vehicle seats.
An inflow opening is provided for the occupant side wall portion arranged on the occupant side and the vehicle body side wall portion arranged on the vehicle body side at the completion of expansion, and is opened in the vehicle body side wall portion for inflowing expansion gas. An airbag having a configuration in which a mounting portion arranged on the peripheral edge of the inflow opening and fixed to a mounting portion is arranged.
The airbag includes a main bag portion having a vent hole for forming an outer peripheral wall when expansion is completed and exhausting excess expansion gas, and an inner bag portion expanding in the main bag portion.
The inner bag portion is provided with the inflow opening and the mounting portion together with the main bag portion, and is on the upstream side to the main bag portion side in the flow of the expansion gas flowing in through the inflow opening. As described above, it has an outflow hole portion that allows the expansion gas to flow out to the main bag portion side, and is supported by the peripheral edge of the mounting portion when the expansion is completed.
The outflow hole portion is closed when the inflow amount of the expansion gas from the inflow opening is reduced, and the outflow of the expansion gas to the main bag portion side is restricted .
The outflow hole portion is configured to include an outflow opening formed by cutting out a peripheral wall constituting the inner bag portion, and a cover member capable of closing the outflow opening from the inside of the inner bag portion. ,
The inner bag portion has a vehicle body side panel having the inflow opening and the mounting hole, and a occupant side panel having an external shape substantially the same as the vehicle body side panel, and the vehicle body side panel and the vehicle body side panel. It is made into a bag shape by connecting the outer peripheral edges with the occupant side panel, and the outer shape is substantially the same as the vehicle body side panel and the occupant side panel between the vehicle body side panel and the occupant side panel. It is configured to dispose a partition panel that is set and is coupled to the outer peripheral edge of the vehicle body side panel and the occupant side panel over substantially the entire circumference of the outer peripheral edge.
The partition panel has a communication hole for communicating the occupant side panel side and the vehicle body side panel side, and is provided with a cover portion capable of closing the outflow opening.
The outflow opening is formed at a position near the outer peripheral edge of the vehicle body side panel.
The airbag is characterized in that the total opening area of the vent hole is set to be smaller than the total opening area of the outflow opening . The airbag is mounted on the steering wheel of the vehicle and is mounted on the steering wheel.
The main bag portion is configured as a substantially disk shape capable of covering the upper surface of the handle substantially over the entire inflatable shape seen from the vertical direction side.
The inner bag portion is characterized in that the expansion completed shape seen from the vertical direction side is configured to have a region protruding outward at least in the front-rear direction from the steering wheel in a state of straight-ahead steering. The airbag according to claim 1 . The steering wheel is configured as a modified steering wheel in which the distance from the center of the front portion during steering is set smaller than the separation distance from the center of the portion on the left-right direction in the state of straight-ahead steering. Being done
The inner bag portion expands to the left and right sides while projecting forward from the arrangement area of the inflow opening so that the expansion completed shape seen from the vertical direction side can cover the front side portion of the steering wheel during straight-ahead steering. The airbag according to claim 2 , wherein the airbag is configured to have a substantially semi-elliptical shape. A modified steering wheel in which the steering wheel is set so that the separation distance from the center of the front part and the rear part is smaller than the separation distance of the left-right part from the center in the state of straight-ahead steering. Configured as
The inner bag portion expands from the arrangement region of the inflow opening to both front and rear sides so that the expansion complete shape seen from the vertical direction side can cover the front side portion and the rear side portion of the steering wheel during straight-ahead steering. The airbag according to claim 2 , wherein the airbag is configured to have a substantially rectangular shape.

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