JP7722945B2 - Airbag device - Google Patents

Description

The present invention relates to an airbag device that protects an occupant seated in a vehicle seat from an impact when the vehicle is subjected to an impact from the diagonally outward front of the vehicle seat.

When an impact is applied to a vehicle from the diagonally outward front of a vehicle seat due to an oblique collision or other event, the upper body of the occupant seated in the vehicle seat will tend to move diagonally outward toward the side of the impact due to inertia.

An effective solution to this problem is an airbag device that deploys and inflates an airbag using inflation gas to protect occupants seated in the vehicle seat from impact when the vehicle is hit, or is expected to be hit, from the diagonally outward front of the vehicle seat.

For example, the airbag of the airbag device described in Patent Document 1 includes a main inflation portion (airbag main body) and a sub-inflatable portion (airbag protrusion). Here, the direction toward the center of the seatback in the width direction of the vehicle seat is defined as inward, and the direction away from the center is defined as outward. The main inflation portion deploys and inflates forward, outward of the occupant's upper body. The front end of the main inflation portion is located diagonally forward and outward from the occupant's head.

The sub-inflatable section is adjacent to the inward side of the main inflatable section. It comprises two fabric sections (base fabrics) and an annular sub-peripheral joint section (peripheral seam) that joins the peripheral edges of both fabric sections. The sub-inflatable section is joined to the front end of the main inflatable section in a state of communication with it.

The secondary inflatable portion includes a secondary inflatable main body portion surrounded by a secondary peripheral bonded portion, and a bonded margin portion formed for each fabric portion and positioned around the secondary peripheral bonded portion.
Inflation gas is supplied from the main inflation section to the sub-inflation section through the communication section. The sub-inflation section deploys and inflates inward from the front end of the main inflation section, more specifically, toward a location in front of the occupant's head.

Therefore, the upper body of the occupant attempting to move diagonally forward and outward as described above can be received by the main inflatable portion and the sub-inflatable portion, thereby protecting the upper body from impact.
The words in parentheses following the names of the components indicate the names of the components used in Patent Document 1.

Japanese Patent Application Laid-Open No. 2006-8105

However, with the airbag device described in Patent Document 1, if the head attempts to move diagonally forward and outward in response to an impact to the vehicle, rotating around the axis of the neck, there is a risk that the head may come into contact with the connecting portion.

The airbag device that solves the above problem is an airbag device that deploys and inflates an airbag with inflation gas to protect an occupant seated in the vehicle seat from an impact that is applied to the vehicle from the diagonally outward front of the vehicle seat, or that is predicted to be applied to the vehicle. In the width direction of the seatback of the vehicle seat, the direction toward the center of the seatback in the same width direction is defined as inward, and the direction away from the center is defined as outward. The airbag has a main inflation section that deploys and inflates outside the occupant, and a sub-inflatable section located adjacent to and inward of the main inflation section. The secondary inflation portion comprises a secondary outer fabric portion connected to the main inflation portion in a state of being in communication with the main inflation portion, a secondary inner fabric portion located inward of the secondary outer fabric portion, and an annular secondary peripheral joint portion connecting the peripheral edge of the secondary outer fabric portion and the peripheral edge of the secondary inner fabric portion. The secondary inflation portion comprises a secondary inflation main body portion surrounded by the secondary peripheral joint portion and that deploys and inflates diagonally forward and outward of the occupant's head by the inflation gas that has passed through the main inflation portion, and joint margins formed for each of the secondary outer fabric portion and the secondary inner fabric portion and positioned around the secondary peripheral joint portion, with the rear portions of the joint margins located inside the secondary inflation main body portion.

With the above configuration, when an impact is applied to the vehicle from diagonally outward and forward of the vehicle seat, the upper body, including the head, of the occupant seated in the vehicle seat will tend to move diagonally outward and forward, toward the side of the impact, due to inertia. At this time, the occupant's head will also tend to rotate around the axis of the neck.

In an airbag device, when an impact is applied to the vehicle from the diagonally outward front of the vehicle seat, or when an impact is predicted, inflation gas is supplied to the main inflation section. Some of the supplied inflation gas flows through the communication section into the sub-inflation section, which is connected to the main inflation section. The inflation gas causes the main inflation section and the sub-inflation section to deploy and inflate, respectively.

The main inflation section deploys and inflates outward from the occupant's upper body. As a result, the occupant's upper body is supported by the main inflation section, preventing the upper body from moving diagonally forward and outward, protecting the upper body from impact.

The sub-inflating section is located adjacent to and inward of the main inflating section, and deploys and inflates diagonally forward and outward from the occupant's head. Therefore, even if the occupant's head attempts to move diagonally forward and outward while rotating around the axis of the neck, this rotational movement is suppressed by contact with the sub-inflating section and the main inflating section.

When the secondary inflation main body deploys and inflates, the rear of the connecting portion is positioned diagonally forward and outward from the occupant. In this regard, with the above-described configuration, the rear of the connecting portion is positioned within the secondary inflation main body. Therefore, the head only comes into contact with the rear surface of the secondary inflation main body, and does not come into contact with the rear of the connecting portion. While avoiding contact with the rear of the connecting portion, the head's movement diagonally forward and outward, which involves rotation, is suppressed by the head's contact with the secondary inflation main body.

In the airbag device, the rear portion of the auxiliary peripheral joint is preferably configured as an auxiliary rear peripheral joint extending linearly in the vertical direction.
According to the above configuration, the secondary rear peripheral joint portion that constitutes the rear portion of the secondary peripheral joint portion extends linearly in the vertical direction, so that the rear surface of the secondary inflatable main body portion also has a shape that extends straight in the vertical direction.

As a result, when the head rotates and moves diagonally forward and outward in response to an impact with the vehicle, the head comes into contact with the rear surface of the sub-inflating main body, which extends straight in the vertical direction. In this case, the area where the rear surface of the sub-inflating main body comes into contact with the head (contact area) is larger than if the rear surface were a convex curved surface. This makes it possible for the head to be received by the larger rear surface of the sub-inflating main body, improving head impact protection.

In the above airbag device, it is preferable that the upper portion of the secondary peripheral joint is formed by a secondary upper peripheral joint, the lower portion of the secondary peripheral joint is formed by a secondary lower peripheral joint, the rear end of the secondary upper peripheral joint is connected to the upper end of the secondary rear peripheral joint via an upper rear boundary, and the rear end of the secondary lower peripheral joint is connected to the lower end of the secondary rear peripheral joint via a lower rear boundary, and the upper rear boundary and the lower rear boundary form a convex arc.

With the above configuration, if the head rotates and moves diagonally forward and outward in response to an impact with the vehicle, the head may come into contact with the rear portion of the auxiliary inflatable main body portion at the portion corresponding to the upper rear boundary or the portion corresponding to the lower rear boundary. In this regard, with the above configuration, both the upper rear boundary and the lower rear boundary are convex arc-shaped. The surfaces of the auxiliary inflatable main body portion at the portions corresponding to the upper rear boundary and the lower rear boundary are convexly curved. Therefore, the head comes into contact with the convexly curved surfaces of the auxiliary inflatable main body portion.

In the airbag device, it is preferable that at least a portion of a front portion of the joining margin portion is disposed outside the sub-inflating main body portion.
The secondary inflatable portion is formed, for example, as follows: A secondary outer fabric portion is laid on a fabric portion constituting the main inflatable portion before fabrication, and the secondary outer fabric portion is joined to the fabric portion.

Next, the secondary inner fabric portion is placed on the opposite side of the secondary outer fabric portion from the above fabric portion, sandwiching the secondary outer fabric portion. A non-annular secondary peripheral bonded portion (before the fabric portion is annular) is formed at the peripheral edges of the secondary outer fabric portion and the secondary inner fabric portion, at a location that will become the bonded portion located inside the secondary inflatable main body portion. This non-annular secondary peripheral bonded portion bonds a portion of the peripheral edge of the secondary outer fabric portion to a portion of the peripheral edge of the secondary inner fabric portion. A non-annular bonded portion is formed around the non-annular secondary peripheral bonded portion. This leaves portions of the peripheral edges of the secondary outer fabric portion and the secondary inner fabric portion that are not bonded by the secondary peripheral bonded portion.

The secondary inner fabric portion is turned inside out through the areas not yet joined by the secondary peripheral joints. The peripheral edges of the inverted secondary outer fabric portion and the secondary inner fabric portion are overlapped at the areas not yet joined by the secondary peripheral joints. The remaining secondary peripheral joints are formed on the secondary outer fabric portion and the secondary inner fabric portion so that the secondary peripheral joints form a ring.

The area of the secondary outer and inner cloth portions surrounded by the annular secondary peripheral joint portion forms the secondary inflatable main body portion. A portion of the joint margin is also formed on the outside of the secondary inflatable main body portion. This portion constitutes at least a portion of the front of the joint margin.

In this way, in order to arrange a part (rear part) of the connecting margin portion inside the secondary inflatable main body portion, it is necessary to adopt a configuration in which a part of the connecting margin portion is arranged outside the secondary inflatable main body portion when manufacturing the secondary inflatable portion.
In this regard, with the above-described configuration, at least a portion of the front portion of the connecting margin is disposed outside the secondary main body portion. The portion of the connecting margin disposed outside the secondary main body portion is located at the farthest point from the head. This makes it less likely that the head will come into contact with the portion of the connecting margin disposed outside the secondary main body portion.

The above airbag device can prevent the head from coming into contact with the connecting portion of the sub-inflatable portion.

1 is a partial plan view of a vehicle equipped with a far side airbag device according to an embodiment. FIG. 3 is a partial cross-sectional plan view showing the internal structure of a side portion of a seat back in which an airbag module is housed in the embodiment. FIG. 2 is a partial perspective view showing the airbag in which both the main inflation portion and the sub-inflatable portion are deployed and inflated, together with an occupant and a vehicle seat in the embodiment. FIG. 2 is a partial plan view showing the positional relationship between the vehicle seat, the airbag, the occupant, and the side wall portion in the embodiment. FIG. 2 is a partial plan view showing the deployed and inflated airbag together with the occupant's head in the embodiment. FIG. 2 is a partial cross-sectional plan view showing the internal structure of the deployed and inflated airbag together with the head of an occupant in the embodiment. This is a cross-sectional view taken along line 7-7 in Figure 5. 7 is a partial cross-sectional plan view corresponding to FIG. 6, showing the deployed and inflated airbag of the modified example together with the occupant's head. FIG.

Hereinafter, an embodiment in which an airbag device is embodied as a far side airbag device for a vehicle will be described with reference to FIGS. 1 to 7. FIG.
In the following description, the forward direction of the vehicle is referred to as the front, and the backward direction is referred to as the rear. Furthermore, the up-down direction refers to the vertical direction of the vehicle, and the left-right direction refers to the width direction of the vehicle, which corresponds to the left-right direction when the vehicle is moving forward. Furthermore, it is assumed that an occupant with a physique similar to that of a crash test dummy is seated in the vehicle seat. Furthermore, a seat belt device (not shown) for restraining the occupant seated in the vehicle seat is provided in the vehicle interior.

As shown in FIG. 1, both left and right sides of vehicle 10 are formed by side walls 11, 12, which are made up of doors, pillars, etc. Inside the vehicle cabin, vehicle seats 13, 14 are arranged side by side in the left and right direction as front seats. Vehicle seat 13, which is closer to side wall 11, functions as the driver's seat, and occupant (driver) P1 sits there. Vehicle seat 14, which is closer to side wall 12, functions as the passenger seat, and occupant (passenger seat occupant) P2 sits there. Vehicle seats 13, 14 have similar configurations. Therefore, only vehicle seat 13 will be described here.

[General Configuration of Vehicle Seat 13]
As shown in Figures 2 and 4, the vehicle seat 13 includes a seat cushion 15, a seat back 16, and a headrest 20. The seat cushion 15 is where the occupant P1 sits and is configured to be slidable in the front-to-rear direction. The seat back 16 is configured to support the upper body of the occupant P1 from behind. The seat back 16 stands upright from the rear of the seat cushion 15 and is configured to have an adjustable inclination angle. The headrest 20 is configured to support the head PH of the occupant P1 from behind and is disposed on the seat back 16. The vehicle seat 13 is disposed with the seat back 16 facing forward. The width direction of the vehicle seat 13 thus disposed coincides with the left-to-right direction.

Here, as shown in Figure 4, in order to identify each part of the seat back 16 in the width direction, the center part 16c of the seat back 16 in the width direction is used as the reference. In the width direction, the direction approaching the center part 16c is referred to as "inward," and the direction moving away from the center part 16c is referred to as "outward."

Figure 2 shows the internal structure of the side portion 17 of the seat back 16 of the vehicle seat 13, which is closer to the vehicle seat 14. A seat frame, which forms the framework of the seat back 16, is located inside the seat back 16.

A side frame portion 18, which forms part of the seat frame, is located inside the side portion 17. The side frame portion 18 is formed by bending a metal plate or other processes.

A seat pad 19 made of an elastic material such as urethane foam is disposed in front of the seat frame, including the side frame portions 18. A backboard 21 is disposed behind the seat frame. The seat pad 19 is covered with a skin, but this skin is not shown in Figure 2.

A storage compartment 22 is provided inside the side portion 17, outside the side frame portion 18. The storage compartment 22 is a space that houses the airbag module ABM, which is the main component of the far side airbag device.

A slit 23 extends diagonally forward and outward from the outer corner of the front portion of the storage compartment 22. The area sandwiched between the front corner 19c of the seat pad 19 and the slit 23 (the area surrounded by a two-dot chain line in Figure 2) forms a breakable portion 24 that will be broken by the airbag 31, which will be described later.

[About the Airbag Module ABM]
The airbag module ABM comprises, as its main components, an airbag 31 and a gas generator 25 for supplying inflation gas to the airbag 31. Next, each of these components will be described.

<Gas generator 25>
The gas generator 25 includes an inflator 26 and a retainer 27 that covers the inflator 26. In this example, a type known as a pyrotype inflator 26 is used. The inflator 26 is cylindrical and contains a gas generating agent (not shown) that generates inflation gas. The inflator 26 has a gas ejection portion 26a at its upper end. A harness (not shown) that serves as input wiring for transmitting an activation signal to the inflator 26 is connected to the lower end of the inflator 26.

Instead of the pyrotype inflator 26 that uses the gas generating agent described above, a type that uses explosives or the like to rupture the bulkhead of a high-pressure gas cylinder filled with high-pressure gas, thereby ejecting inflation gas, may be used.

The retainer 27, on the other hand, functions as a diffuser that controls the direction in which inflation gas is ejected, and also functions to fasten the inflator 26 to the side frame portion 18 together with the airbag 31 and other components. Most of the retainer 27 is formed into a cylindrical shape by bending a metal plate or other plate material. A bolt 28 extending inward is fixed to the retainer 27 as a component for attaching it to the side frame portion 18.

The gas generator 25 may be an integrated unit of the inflator 26 and retainer 27. The gas generator 25 may also be configured solely from the inflator 26 without the retainer 27. In this case, the bolt 28 is fixed to the inflator 26.

<Airbag 31>
3 and 4, the airbag 31 includes a main inflation portion 32 and a sub-inflatable portion 41 having a smaller capacity than the main inflation portion 32. Both the main inflation portion 32 and the sub-inflatable portion 41 are formed from pieces of fabric (also called base fabric, panel fabric, etc.). The pieces of fabric are made of a strong, flexible, and easily foldable material, such as a woven fabric made from polyester yarn, polyamide yarn, etc.

<Main expansion section 32>
The main inflatable portion 32 is formed, for example, by folding a piece of fabric in half, overlapping it laterally, and joining the peripheral edges of the overlapped portion at a main peripheral joint 33. Here, to distinguish between the two overlapping portions of the main inflatable portion 32, the outermost portion will be referred to as the main outer fabric portion 34 and the innermost portion will be referred to as the main inner fabric portion 35. The main peripheral joint 33 is formed by sewing (sewing with sewing thread) the peripheral edges of the main outer fabric portion 34 and the main inner fabric portion 35 together. In Figure 3, the main peripheral joint 33 is represented by intermittently arranged thick lines of a fixed length. These thick lines indicate the sewing thread as viewed from the side. This also applies to the secondary peripheral joint 51 in Figure 3.

The main inflatable portion 32 may be made of two pieces of fabric. In this case, the main outer fabric portion 34 and the main inner fabric portion 35, which are made of separate pieces of fabric, are overlapped and joined all around the periphery by the main peripheral joining portion 33.

The main peripheral joint 33 may be formed by a means other than sewing, for example, by adhesion. This also applies to the sub-peripheral joint 51 and the annular joint 46 described below.
The main inflatable portion 32 is designed to protect most of the upper body of the occupant P1, in this embodiment, the area from the chest PT to the head PH. The main inflatable portion 32 is formed in a shape and size that allows it to deploy and inflate outside the areas to be protected.

As shown in Figures 2 and 4, once the main inflation section 32 has been deployed and inflated, it is tilted relative to the longitudinal direction so that the forward end is positioned further outward. The tilted position of the main inflation section 32 is achieved, for example, by an external tether (not shown) that is disposed outside the main inflation section 32 and stretches between the main inflation section 32 and a high-strength member, such as the side frame section 18, within the side section 17 of the seat back 16. The external tether is made of a strip-shaped piece of fabric made of the same material as the main inflation section 32 and the sub-inflation section 41.

The gas generator 25 is positioned within the rear end of the main inflation section 32, extending generally vertically. Furthermore, bolts 28 are inserted through the main inner fabric section 35, thereby positioning the gas generator 25 relative to the main inflation section 32 and locking it in place.

<Sub-inflatable section 41>
3 and 4, the sub-inflating portion 41 is disposed in a location adjacent and inward of the front portion of the main inflating portion 32. The sub-inflating portion 41 is formed in a shape and size that allows it to deploy and inflate at a location diagonally forward and outward of the head PH of the occupant P1, which is a location to be protected.

As shown in Figures 3 and 5 to 7, the secondary inflatable portion 41 comprises a secondary outer cloth portion 42 and a secondary inner cloth portion 43 that have the same outer shape. The secondary outer cloth portion 42 and the secondary inner cloth portion 43 are formed from separate pieces of cloth. The secondary outer cloth portion 42 and the secondary inner cloth portion 43 are each based on a rectangular piece of cloth, with their corners shaped like convex arcs. The secondary outer cloth portion 42 is adjacent to the main inner cloth portion 35 of the main inflatable portion 32. The secondary outer cloth portion 42 is connected to the main inner cloth portion 35 while being connected to the main inflatable portion 32.

More specifically, as shown in Figure 6, the secondary outer fabric portion 42 has a secondary communication hole 45 that connects the inside and outside of the secondary inflatable portion 41. The main inner fabric portion 35 of the main inflatable portion 32 has a main communication hole 36 formed adjacent to the secondary communication hole 45, which connects the inside and outside of the main inflatable portion 32.

The area surrounding the main communication hole 36 in the main inner cloth portion 35 and the area surrounding the secondary communication hole 45 in the secondary outer cloth portion 42 are overlapped and joined by an annular joint 46. Similar to the main peripheral joint 33, the annular joint 46 is formed by sewing the main inner cloth portion 35 and the secondary outer cloth portion 42 together. The main communication hole 36 and the secondary communication hole 45 connect the secondary inflatable portion 41 to the main inflatable portion 32.

Combinations of main communication holes 36, auxiliary communication holes 45, and annular connecting portions 46 are provided in multiple locations. Therefore, the main expansion portion 32 and the auxiliary expansion portion 41 are in communication with each other via the main communication holes 36 and auxiliary communication holes 45 provided in multiple locations for each of the above combinations.

The secondary inner cloth portion 43 is disposed on the opposite side of the secondary outer cloth portion 42 from the main inflatable portion 32 , i.e., inward of the secondary outer cloth portion 42 .
As shown in Figures 6 and 7, the peripheral edges of the secondary outer fabric portion 42 and the secondary inner fabric portion 43 are overlapped and joined by a secondary peripheral joint portion 51. Similar to the main peripheral joint portion 33 and the annular joint portion 46, the secondary peripheral joint portion 51 is formed by sewing the secondary outer fabric portion 42 and the secondary inner fabric portion 43 together. The secondary peripheral joint portion 51 is formed at a fixed distance from the outer edges of the secondary outer fabric portion 42 and the secondary inner fabric portion 43, and forms a rectangular ring shape. In Figure 7, the secondary peripheral joint portion 51 is represented by a plurality of dots arranged at regular intervals. These dots represent the cross section of the sewing thread on a plane passing through the sewn portion.

The rear portion of the secondary peripheral joint 51 is formed by a secondary rear peripheral joint 55 that extends linearly in the vertical direction along the rear edges of the secondary outer cloth portion 42 and the secondary inner cloth portion 43 .
The upper part of the secondary peripheral joint portion 51 is formed by a secondary upper peripheral joint portion 53 that extends linearly in the horizontal direction along the upper edges of the secondary outer cloth portion 42 and the secondary inner cloth portion 43. The rear end of the secondary upper peripheral joint portion 53 is connected to the upper end of the secondary rear peripheral joint portion 55 via a convex, arc-shaped upper rear boundary portion 58.

The lower part of the secondary peripheral joint 51 is formed by a secondary lower peripheral joint 54 that extends horizontally in a straight line along the lower edges of the secondary outer cloth portion 42 and the secondary inner cloth portion 43. The rear end of the secondary lower peripheral joint 54 is connected to the lower end of the secondary rear peripheral joint 55 via a convex arc-shaped lower rear boundary portion 59.

The front portion of the secondary peripheral joint 51 is formed by a secondary front peripheral joint 52 that extends vertically along the front edges of the secondary outer cloth portion 42 and the secondary inner cloth portion 43. The upper end of the secondary front peripheral joint 52 is connected to the front end of the secondary upper peripheral joint 53 via a convex, arc-shaped upper front boundary 56. The lower end of the secondary front peripheral joint 52 is connected to the front end of the secondary lower peripheral joint 54 via a convex, arc-shaped lower front boundary 57.

The upper and lower rear boundaries 58 and 59 are curved with a radius of 30 mm or more. In this embodiment, the upper and lower front boundaries 56 and 57 are also curved with a radius of a similar size. Note that the upper and lower front boundaries 56 and 57 may be angular instead of convex arcs.

The secondary inflation section 41 includes a secondary inflation main body section 61 and a connecting portion 62. The secondary inflation main body section 61 is surrounded by the secondary peripheral connecting portion 51 and has a rectangular shape in side view (see Figure 3). The secondary inflation main body section 61 deploys and inflates diagonally forward and outward of the head PH of the occupant P1 due to the inflation gas that has passed through the main inflation section 32.

The joining allowance portion 62 is formed for each of the secondary outer cloth portion 42 and the secondary inner cloth portion 43 and is positioned around the secondary peripheral joining portion 51 .
A portion of the joining margin 62 is disposed outside the secondary inflatable main body portion 61. More specifically, a portion 62a of the front portion of the joining margin 62, which is adjacent to the front of the secondary front peripheral joining portion 52, is disposed outside the secondary inflatable main body portion 61 (see FIG. 3). The remainder 62b of the joining margin 62 is disposed inside the secondary inflatable main body portion 61. This remainder 62b includes the rear portion of the joining margin 62, more specifically, the peripheral portions of the secondary rear peripheral joining portion 55, the upper rear boundary portion 58, and the lower rear boundary portion 59.

<Fixing manner of airbag module ABM>
2, the airbag module ABM is made compact for storage by folding up a portion of the main inflation portion 32, which is different from the rear end portion where the gas generator 25 is housed, together with the sub-inflating portion 41, the external tether, etc. Note that the sub-inflating portion 41, the external tether, etc. are not shown in FIG.

The airbag module ABM in its storage configuration is stored in the storage compartment 22. The bolt 28 exposed from the main inflation section 32 is inserted into the side frame section 18 from the outside. A portion of the bolt 28 protrudes inward beyond the side frame section 18, and a nut 29 is fastened to this protruding portion. This fastening secures the gas generator 25, along with the rear end of the main inflation section 32, to the side frame section 18 from the outside.

The gas generator 25 may be fixed to the side frame portion 18 by a member other than the bolt 28 and nut 29 described above. Furthermore, if the gas generator 25 is composed of only the inflator 26, the inflator 26 may be fixed to the side frame portion 18 by a bolt 28 fixed to the inflator 26 and a nut 29 tightened thereto.

<Other configurations of the far side airbag device>
In addition to the airbag module ABM described above, the far side airbag device includes an impact sensor 71 and a control device 72. The impact sensor 71 is composed of an acceleration sensor or the like, and detects an impact applied to the vehicle 10 from the diagonally outward front of the vehicle seat 13.

The control device 72 is configured as a circuit including one or more processors that operate according to a computer program (software), one or more dedicated hardware circuits that execute at least some of the various processes, or a combination of these. The control device 72 controls the activation of the gas generator 25 based on the detection signal from the impact sensor 71. In this embodiment, when the impact sensor 71 detects an impact from the diagonally outward front, the control device 72 outputs an activation signal to the gas generator 25 to activate the gas generator 25.

[Action and effect]
Next, the operation of the present embodiment configured as described above will be described. The effects resulting from the operation will also be described. It is assumed that the occupant P1 is seated in the vehicle seat 13 in a proper posture and that the upper body of the occupant P1 is restrained in the vehicle seat 13 by the seat belt device.

<(1) Creation of the sub-inflating portion 41>
The secondary inflatable portion 41 is created, for example, as follows: Before the main inflatable portion 32 is created, the secondary outer fabric portion 42 having secondary communicating holes 45 is superimposed on the main inner fabric portion 35 having main communicating holes 36. With the secondary communicating holes 45 aligned with the main communicating holes 36, an annular joint 46 is formed around the main communicating holes 36 in the main inner fabric portion 35 and the secondary communicating holes 45 in the secondary outer fabric portion 42. Then, with the main communicating holes 36 and the secondary communicating holes 45 communicating with each other, the main inner fabric portion 35 and the secondary outer fabric portion 42 are joined (sewn together) at the annular joint 46.

Next, the secondary inner cloth portion 43 is positioned on the opposite side of the secondary outer cloth portion 42 from the main inner cloth portion 35. Non-annular secondary peripheral joint portions 51, which are not yet annular, are formed at locations on the peripheral edges of the secondary outer cloth portion 42 and the secondary inner cloth portion 43 that will become the remaining portions 62b of the joining allowance portion 62. The non-annular secondary peripheral joint portions 51 in this case are the secondary upper peripheral joint portion 53, secondary lower peripheral joint portion 54, secondary back peripheral joint portion 55, upper front boundary portion 56, lower front boundary portion 57, upper back boundary portion 58, and lower back boundary portion 59 in Figure 7. The non-annular secondary peripheral joint portions 51 join a portion of the peripheral edge of the secondary outer cloth portion 42 to a portion of the peripheral edge of the secondary inner cloth portion 43. The remaining portions 62b of the non-annular joining allowance portion 62 are formed around the non-annular secondary peripheral joint portions 51. There are areas along the periphery of each of the secondary outer fabric portion 42 and the secondary inner fabric portion 43 that are not joined by the secondary peripheral joining portion 51.

The secondary inner cloth portion 43 is turned inside out through the unjoined portion. The peripheral edges of the inverted secondary outer cloth portion 42 and the secondary inner cloth portion 43 are overlapped at the portions not yet joined by the secondary peripheral joining portion 51. The remaining secondary peripheral joining portions 51 (secondary front peripheral joining portions 52) are formed on the secondary outer cloth portion 42 and the secondary inner cloth portion 43 so that the secondary peripheral joining portion 51 is annular. The upper portion of the secondary front peripheral joining portion 52 intersects with the upper front border portion 56, and the lower portion of the secondary front peripheral joining portion 52 intersects with the lower front border portion 57.

As a result, the secondary peripheral joints 51 are connected to form a ring. The area of the secondary outer fabric portion 42 and the secondary inner fabric portion 43 that is surrounded by the ring-shaped secondary peripheral joints 51 becomes the secondary inflatable main body portion 61. Furthermore, a portion 62a of the joint margin 62 is formed outside the secondary inflatable main body portion 61. This portion 62a constitutes at least a portion of the front of the joint margin 62.

In this way, in order to position a portion (rear portion) of the connecting portion 62 inside the secondary inflatable main body portion 61, a configuration is adopted in which a portion of the connecting portion 62 is positioned outside the secondary inflatable main body portion 61 when creating the secondary inflatable portion 41.

<(2) When the far side airbag device is not activated>
2 does not detect an impact to the vehicle 10 from the diagonally outward front of the vehicle seat 13, the control device 72 does not output an activation signal to the gas generator 25. No inflation gas is ejected from the gas ejection portion 26a of the inflator 26. The airbag module ABM remains stored in the storage portion 22 in the storage configuration, as shown in FIG.

(3) When the far side airbag device is activated
Next, a case will be described in which an impact is applied to the front side of the vehicle 10 from the diagonally outward front of the vehicle seat 13 due to an oblique collision or the like while the vehicle 10 is traveling, as indicated by the solid arrow in FIG.

In this case, as shown in Figures 5 and 6, the upper body, including the head PH, of the occupant P1 will tend to move due to inertia diagonally forward and outward, toward the side of the impact, as indicated by arrow A. At this time, the head PH will tend to rotate around the axis AL of the neck PN, as indicated by arrow B.

(3-1) In contrast, in the far side airbag device of this embodiment, when the impact sensor 71 in FIG. 2 detects the application of the impact, the control device 72 outputs the activation signal to the gas generator 25 in response to the detection signal. When inflation gas is ejected from the gas ejection portion 26a of the inflator 26 in response to this activation signal, the inflation gas is first supplied to the main inflation portion 32 of the airbag 31 in the airbag module ABM in the storage configuration.

The supply of inflation gas to the main inflation section 32 increases the internal pressure of the main inflation section 32. The main inflation section 32 inflates while unfolding, i.e., while unfolding.
During the deployment and inflation, the main inflation section 32, together with the sub-inflation section 41, the outer tether, etc., presses against the seat pad 19 near the storage compartment 22 in FIG. 2 , rupturing the seat pad 19 at the rupture portion 24. As inflation gas continues to be supplied thereafter, the main inflation section 32, together with the sub-inflation section 41, etc., exits the storage compartment 22 through the ruptured portion, leaving its rear end, which is fixed to the side frame 18, inside the storage compartment 22. The main inflation section 32 deploys and inflates diagonally forward and upward between the vehicle seats 13, 14, i.e., outside the upper body of the occupant P1, as shown in FIGS. 3 and 4 . Therefore, the upper body of the occupant P1 is received by the main inflation section 32, preventing the upper body from moving diagonally forward and outward, thereby protecting the upper body from impact.

(3-2) As shown in Figure 6, some of the inflation gas supplied to the main inflation section 32 flows into the sub-inflation section 41 through the main communication hole 36 and the sub-inflation hole 45 midway through the deployment and inflation of the main inflation section 32.

As shown in Figures 5 and 6, the inflation gas flowing in as described above causes the sub-inflatable section 41 to deploy and inflate adjacent to the front inboard portion of the main inflatable section 32, diagonally forward and outward of the head PH.

As a result, even if the head PH attempts to move diagonally forward and outward while rotating around the axis AL of the neck PN, the head PH is received by the sub-inflating portion 41 and the main inflating portion 32. This prevents the head PH from moving diagonally forward and outward while rotating. In other words, the head PH is restrained and protected from impact.

(3-3) In addition, in this embodiment, the sub-inflating section 41 deploys and inflates forward in the direction of movement of the head PH. Moreover, both the main inflating section 32 and the sub-inflating section 41 are inclined in the front-to-rear direction so that the more forward they are positioned outward when they have completed deployment and inflation. Therefore, the boundary between the main inflating section 32 and the sub-inflating section 41 is located forward in the direction of movement of the head PH.

Therefore, the head PH is received by both the main inflation portion 32 and the sub-inflating portion 41, and the movement of the head PH diagonally forward and outward, which is accompanied by rotation, can be further suppressed.
(3-4) Furthermore, in this embodiment, as shown in Figures 6 and 7, the secondary rear peripheral joint 55 of the secondary peripheral joint 51 extends linearly in the vertical direction, so the rear surface of the secondary inflatable main body portion 61 also has a shape that extends linearly in the vertical direction.

As a result, when the head PH rotates and moves diagonally forward and outward in response to an impact to the vehicle 10, the head PH comes into contact with the rear surface of the secondary expanding main body portion 61, which extends straight in the vertical direction. At this time, the area over which the rear surface of the secondary expanding main body portion 61 comes into contact with the head PH (contact area) is wider than if the rear surface were a convex curved surface. As a result, the head PH can be received by the wider rear surface of the secondary expanding main body portion 61, improving its ability to protect the head PH from impact.

(3-5) When the sub-inflating main body portion 61 deploys and inflates, the rear portion of the connecting margin portion 62 is positioned diagonally forward and outward of the occupant P1.
In this regard, in this embodiment, the rear portion of the connecting margin 62 is disposed within the secondary expanding main body portion 61. Therefore, the head PH only contacts the rear surface of the secondary expanding main body portion 61, and does not contact the rear portion of the connecting margin 62. While avoiding contact with the rear portion of the connecting margin 62, movement of the head PH diagonally forward and outward, which involves rotation, can be suppressed by contact with the rear surface of the secondary expanding main body portion 61.

(3-6) As explained in section (1) above, in order to position a portion of the connection margin portion 62 (remaining portion 62b) inside the secondary expansion main body portion 61, it is necessary to position a portion of the connection margin portion 62 (portion 62a) outside the secondary expansion main body portion 61 when creating the secondary expansion portion 41.

In this regard, in this embodiment, only the portion 62a, which is a part of the front portion of the connection margin 62, is positioned outside the secondary expansion main body portion 61. This portion 62a is located at the front of the connection margin 62, which is the part of the connection margin 62 that is farthest from the head PH. This makes it more difficult for the head PH to come into contact with the portion 62a of the connection margin 62 that is positioned outside the secondary expansion main body portion 61.

(3-7) If the head PH rotates and moves diagonally forward and outward in response to an impact to the vehicle 10, the head PH may come into contact with the rear of the auxiliary expanding main body portion 61 at a portion corresponding to the upper rear boundary portion 58 or the lower rear boundary portion 59.

In this regard, in this embodiment, both the upper and lower rear boundaries 58 and 59 are convex arc-shaped. The surfaces of the auxiliary inflatable main body 61 at the locations corresponding to the upper and lower rear boundaries 58 and 59 are convexly curved. Therefore, the head PH comes into contact with these convexly curved surfaces. This prevents the head PH from coming into contact with sharp points when coming into contact with the upper and lower rear boundaries 58 and 59.

<(4) Actions and effects other than those mentioned above>
(4-1) As shown in Fig. 7, in this embodiment, the secondary peripheral joint portion 51 is composed of a secondary front peripheral joint portion 52, a secondary rear peripheral joint portion 55, a secondary upper peripheral joint portion 53, and a secondary lower peripheral joint portion 54, each of which is linear. This configuration makes the secondary peripheral joint portion 51 rectangular and annular, and the secondary inflatable main body portion 61 rectangular in side view (see Fig. 3).

Therefore, the expanded thickness of the sub-expansion main body portion 61 when deployed and expanded can be made larger more efficiently than when the sub-expansion main body portion 61 has another shape in side view, for example, a triangular shape.
(4-2) In this embodiment, the secondary outer cloth portion 42 and the secondary inner cloth portion 43 are formed using rectangular pieces of cloth as the base, with the corners formed in a convex arc shape. This allows the secondary outer cloth portion 42 and the secondary inner cloth portion 43 to be smaller than when the corners are right-angled. This reduces the amount of cloth required to form the secondary outer cloth portion 42 and the secondary inner cloth portion 43.

As a result, the size of the airbag 31 when folded, and therefore the size of the airbag module ABM when in its storage configuration, can be reduced, improving the ease of installation on the vehicle seat 13.

In addition, in this embodiment, the upper front border 56, lower front border 57, upper back border 58, and lower back border 59 are each formed in a convex arc shape to match the shapes of the corners of the secondary outer cloth portion 42 and secondary inner cloth portion 43. Therefore, compared to when these portions are formed by bending them at right angles, the lengths of the upper front border 56, lower front border 57, upper back border 58, and lower back border 59, and ultimately the length of the secondary peripheral joining portion 51, can be shortened.

[Example of change]
The above embodiment can also be implemented as a modified example in which it is modified as follows: The above embodiment and the following modified example can be implemented in combination with each other within a range where no technical contradiction occurs.

<About the airbag 31>
As shown in Figure 8, the main inflation section 32 may assume a posture aligned with the front-to-rear direction when fully deployed and inflated. In this case, the posture (inclination with respect to the front-to-rear direction) of the main inflation section 32 and the sub-inflating section 41 relative to the upper body of the occupant P1, particularly the head PH, differs from that of the above embodiment. However, in this case, as in the above embodiment, the main inflation section 32 and the sub-inflating section 41 can receive the head PH and suppress any movement of the head PH diagonally forward and outward, which may involve rotation.

In this case, as in the above embodiment, contact of the head PH with the rear of the connecting portion 62 can be prevented. Furthermore, the head PH can be brought into contact with the convex curved surfaces corresponding to the upper rear boundary portion 58 and the lower rear boundary portion 59.

The shape or size of the main inflatable portion 32 may be changed to enlarge, reduce, or change the area of the occupant P1 that is to be protected by the main inflatable portion 32.
The main inflation section 32 may be one that inflates almost entirely as in the above embodiment, or it may have a non-inflatable section that is not supplied with inflation gas and does not inflate.

The number of combinations of the main communication hole portions 36, the sub-communication hole portions 45, and the annular connecting portions 46 in FIG. 6 may be changed to one.
The main communication hole 36 and the sub communication hole 45 may have, for example, a circular, elliptical, or polygonal shape such as a square.

The main communication hole 36 and the sub-communication hole 45 may be formed as elongated spaces such as slots or slits.
The location of the connecting portion 62 inside the secondary expanding main body portion 61 may be changed, provided that at least the rear portion of the connecting portion 62 is positioned inside the secondary expanding main body portion 61.

- The portion of the connecting portion 62 that is positioned outside the secondary expanding main body portion 61 may be changed. For example, the entire front portion of the connecting portion 62 may be positioned outside the secondary expanding main body portion 61. Also, the upper or lower portion of the connecting portion 62 may be positioned outside the secondary expanding main body portion 61.

At least one of the upper rear boundary portion 58 and the lower rear boundary portion 59 may be formed in a shape other than a convex arc shape.
<Regarding the control device 72>
When the impact sensor 71 detects an impact from the side in addition to the obliquely outward front direction, the control device 72 may output an activation signal to the gas generator 25. This modification provides the following effects.

When an impact is applied to the side wall portion 12 from the outside due to a side collision or the like, as indicated by the dashed-dotted arrow in Figure 1, the upper body of occupant P1 will tend to move toward the side of the impact due to inertia.

However, when inflation gas is supplied, the main inflation section 32 deploys and inflates outside the upper body of the occupant P1. As a result, the main inflation section 32 receives the upper body and protects the occupant P1 from the impact.

The specifications of the control device 72 may be modified to output an activation signal to the gas generator 25 when it is predicted that an impact will be applied to the vehicle 10 from the diagonally outward front of the vehicle seat 13 .
<Applicable locations for far side airbag devices>
The far side airbag device may be applied to the vehicle seat 14 instead of or in addition to the vehicle seat 13 .

The far side airbag device is not limited to being applied to the front seats (driver's seat and passenger seat) of the vehicle 10, but may also be applied to the rear seats (seats in the second row and beyond).
In the case of a vehicle in which the vehicle seat is positioned with the seat back 16 facing in a direction other than forward, for example, facing to the side, the far side airbag device can also be applied to such vehicle seats.

If the vehicle is of a type in which three or more vehicle seats are arranged side by side in the width direction, the far side airbag device can also be applied to these vehicle seats.
<Others>
The airbag device is not limited to a far-side airbag device, and may be applied to a normal side airbag device (also called a near-side airbag device). In this case, the airbag module ABM is housed in the side of the seat back 16 of the vehicle seat 13, 14 that is far from the adjacent vehicle seat 14, 13, or in other words, in the side that is closer to the adjacent side wall portion 11, 12.

Vehicles to which the airbag device is applied include not only private cars but also various industrial vehicles.
The airbag device may also be applied to an airbag device mounted on a seat in a vehicle other than a car, such as an aircraft or a ship.

10...Vehicle (vehicle)
13, 14... Vehicle seat (vehicle seat)
DESCRIPTION OF SYMBOLS 16: Seat back 16c: Central portion 31: Airbag 32: Main inflatable portion 41: Sub-inflatable portion 42: Sub-outer fabric portion 43: Sub-inner fabric portion 51: Sub-peripheral joint portion 53: Sub-upper peripheral joint portion 54: Sub-lower peripheral joint portion 55: Sub-rear peripheral joint portion 58: Upper rear boundary portion 59: Lower rear boundary portion 61: Sub-inflatable main body portion 62: Joint margin portion PH: Head P1, P2: Occupant

Claims (4)

An airbag device that deploys and inflates an airbag with inflation gas when an impact is applied to a vehicle from a diagonally outward front of a vehicle seat, or when such an impact is predicted, to protect an occupant seated in the vehicle seat from the impact,
When a direction toward a center of the seat back in the width direction of the vehicle seat is defined as an inward direction and a direction away from the center of the seat back in the width direction is defined as an outward direction, the airbag includes a main inflation portion that deploys and inflates outside the occupant, and a sub-inflatable portion that is disposed adjacent to and inward of the main inflation portion,
The secondary inflatable portion comprises a secondary outer cloth portion joined to the main inflatable portion in a state of being connected to the main inflatable portion, a secondary inner cloth portion positioned inside the secondary outer cloth portion, and an annular secondary peripheral joining portion joining the peripheral edge of the secondary outer cloth portion and the peripheral edge of the secondary inner cloth portion,
the secondary inflation portion includes a secondary inflation main body portion that is surrounded by the secondary peripheral joint portion and that is deployed and inflated diagonally forward and outward of the occupant's head by the inflation gas that has passed through the main inflation portion, and a joint margin portion that is formed for each of the secondary outer fabric portion and the secondary inner fabric portion and that is positioned around the secondary peripheral joint portion;
The rear portion of the connecting portion is disposed inside the sub-inflatable main body portion. The airbag device according to claim 1, wherein the rear portion of the secondary peripheral joint is configured as a secondary rear peripheral joint extending linearly in the vertical direction. an upper portion of the secondary peripheral joint portion is formed by a secondary upper peripheral joint portion, and a lower portion of the secondary peripheral joint portion is formed by a secondary lower peripheral joint portion;
a rear end of the secondary upper peripheral joint portion is connected to an upper end of the secondary rear peripheral joint portion via an upper rear boundary portion;
a rear end of the secondary lower peripheral joint portion is connected to a lower end of the secondary rear peripheral joint portion via a lower rear boundary portion;
3. The airbag device according to claim 2, wherein the upper and lower rear boundary portions are formed in a convex arc shape. An airbag device according to any one of claims 1 to 3, wherein at least a portion of the front of the connecting portion is positioned outside the sub-inflatable main body portion.