JP7004177B2 - Side airbag device - Google Patents

Description

The present invention relates to a side airbag device.

The side airbag device mounted on a vehicle such as an automobile is provided with an airbag that is stored in a folded state. The device supplies gas from the inflator to the airbag in the event of a side collision of the vehicle, so that the airbag is placed between the occupant seated in the seat of the vehicle and the body side portion of the vehicle. Deploy and inflate from the back to the front of the. The airbag that expands and expands in this way protects the occupant in the event of a side collision of the vehicle. In the above airbag, for the purpose of adjusting the mode of expansion and expansion thereof, for example, a non-expandable portion is formed or a tether is provided as shown in Patent Document 1.

Japanese Patent No. 6131935

By the way, when the above-mentioned airbag is folded and stored, a wrapping cloth or the like is wrapped around the folded airbag and temporarily fixed to keep the airbag folded. When the airbag expands and expands due to the supply of gas from the inflator, the temporary fixing of the wrapping cloth is released along with the expansion and expansion of the airbag, so that the expansion and expansion of the airbag is described above. It is prevented from being hindered by the wrapping cloth.

However, when the folding of the airbag is held by the above-mentioned wrapping cloth or the like, the number of parts of the side airbag device increases due to the need to provide such a wrapping cloth or the like, which leads to an increase in the cost of the device.

An object of the present invention is to provide a side airbag device capable of suppressing an increase in the number of parts.

Hereinafter, means for solving the above problems and their actions and effects will be described.
The side airbag device that solves the above problems supplies the gas from the inflator to the folded and stored airbag, so that the airbag is seated on the seat of the vehicle and the occupant seated on the seat of the vehicle and the body side portion of the vehicle. In between, the vehicle is deployed and expanded from the rear to the front. A non-expandable portion that does not expand due to the supply of gas from the inflator is formed in the central portion in the front-rear direction of the vehicle in the above-mentioned airbag in the expanded and expanded state. At a position inside the width direction of the vehicle in the airbag when deployed and inflated and corresponding to the non-expanded portion, the front portion extends in the front-rear direction of the vehicle and is joined to the front portion of the airbag. At the same time, a tether is provided in which the rear portion is joined to the rear portion of the airbag. The length between the front and rear parts of the tether that are joined to the airbag is shorter than the length between the front and rear parts of the tether that are joined in the airbag. ing. The airbag is folded so that the part between the front part and the rear part of the tether is shortened in the front-rear direction of the vehicle, and the tether is wrapped around the folded part and temporarily fixed. It is stored in a state where the folding of the above part is held.

According to the above configuration, the folding of the folded portion of the airbag is held by using the above tether. When the gas from the inflator is supplied to the folded airbag, the temporary fixing of the tether is released by the expansion and expansion of the airbag, so that the tether expands and expands the airbag. Is not disturbed. Further, the tether is provided in the airbag for the following reasons. That is, when the inflator is downsized to reduce the weight of the airbag device, the amount of gas supplied to the airbag is reduced, but the same air can be properly deployed and expanded even with such a small amount of gas. The non-inflated portion is formed on the bag. Then, for the purpose of maintaining the occupant protection function of the airbag when such a non-expandable portion is formed, the tether is provided inside the airbag in the width direction of the vehicle. Specifically, when the airbag is expanded and expanded, the tether located corresponding to the non-expanded portion receives tension based on the expansion and expansion of the airbag, and the tension acts on the non-tether in the airbag. The occupants are protected at the part corresponding to the inflated part. Therefore, even when the non-expandable portion is formed in the airbag, the occupant protection function of the airbag can be maintained by the tether. By using the above-mentioned tether provided for maintaining the occupant protection function of the airbag in order to hold the fold of the part to be folded when the airbag is stored, a wrapping cloth or the like for holding the fold can be used. There is no need to add new parts.

In the airbag device, the airbag is stored in a folded state in the seat back of the seat, and the rear portion in the front-rear direction of the vehicle under the expanded and inflated state of the airbag is stored. It is fixed to the frame of the seat back. Further, in the above tether, a band portion having a fragile portion, which is a fragile portion, is formed on the front side of the vehicle with respect to the front portion joined to the airbag. Further, the tether is wrapped around the folded portion of the airbag, and the band portion is fixed to the frame of the seat back to realize temporary fixing while holding the folded portion of the airbag. It is supposed to be done.

According to the above configuration, when the folded airbag is unfolded and expanded, the band portion of the tether wound around the airbag is cut at the fragile portion. As a result, the temporary fixing of the airbag while holding the fold of the airbag by the tether is released.

In the airbag device, the portion of the tether between the front and the rear that is joined to the airbag slackens in the tether when the tether is wound around the folded portion of the airbag. A locking portion for locking is provided in a state of holding the.

According to this configuration, when the tether is wound around the folded portion of the airbag, even if there is an excess in the tether in realizing the winding, the tether will be loosened due to the slack in the locking portion. It can be suppressed by adjusting the amount of slack. Then, when the airbag is expanded and expanded through the supply of gas from the inflator to the folded airbag, the locking at the locking portion is released along with the expansion and expansion of the airbag, and the airbag is released with respect to the tether. It becomes possible to apply tension based on expansion and expansion.

According to the present invention, it is possible to suppress an increase in the number of parts.

Side view showing the whole side airbag device. A cross-sectional view showing an enlarged view around the airbag inside the seat back. The plan view which shows the positional relationship between a seat and a body side part in a vehicle. (A) and (b) are a side view showing a state in which the airbag when deployed and inflated is viewed from the inside in the width direction of the vehicle, and a state in which the airbag is viewed from the outside in the width direction of the vehicle. Side view shown. FIG. 4B is a cross-sectional view schematically showing a state in which the airbag is viewed from the direction of arrows AA under the expanded and inflated state of the airbag of FIG. 4 (b). A side view showing the state in which the airbag is folded to be stored in the seat back together with the retainer (inflator). FIG. 6 is a cross-sectional view schematically showing a state in which the airbag of FIG. 6 is viewed from the direction of arrows BB.

Hereinafter, an embodiment of the side airbag device applied to a vehicle such as an automobile will be described with reference to FIGS. 1 to 7.
As shown in FIG. 1, the side airbag device supplies an airbag 3 folded and stored inside a seat back 2 in a vehicle seat 1 and an expansion gas to the airbag 3. Inflator 4 and. The inflator 4, together with the airbag 3, is fixed to a frame 6 extending substantially in the vertical direction along the seat back 2 inside the seat back 2. In the airbag 3 of FIG. 1, the state of being folded and stored in the seat back 2 is shown by a broken line, while the state of being expanded and expanded by receiving the supply of expansion gas from the inflator 4 is a two-dot chain line. It is shown by.

FIG. 2 shows an enlarged view around the airbag 3 inside the seat back 2. As can be seen from FIG. 2, the inflator 4 housed inside the seat back 2 is fixed to the retainer 5 surrounding the inflator 4 by caulking or the like. Further, the retainer 5 is fixed to the frame 6 together with the folded airbag 3 by bolts 7 and nuts 8 (only the upper one is shown in FIG. 2) provided in the upper and lower two stages, respectively. As a result, the inflator 4 is fixed to the frame 6 of the seat back 2 via the retainer 5, and the airbag 3 is also fixed to the frame 6.

As shown in FIG. 1, the side airbag device also includes a control device 9 that controls the supply of expansion gas to the airbag 3 by the inflator 4, and an impact sensor 10 for detecting a side collision of the vehicle. ing. The impact sensor 10 outputs a detection signal to the control device 9 when an impact based on a side collision is applied to the vehicle. The control device 9 operates the inflator 4 based on the detection signal from the impact sensor 10 to supply the expansion gas to the airbag 3. Then, when expansion gas is supplied from the inflator 4 to the folded airbag 3, the airbag 3 expands and expands, leaving a portion near the inflator 4 in the seat back 2 and the same seat. It jumps out from the back 2 to the front (to the right in FIG. 1).

As shown by the alternate long and short dash line in FIG. 3, the airbag 3 protruding from the seat back 2 is located behind the vehicle between the occupant P1 seated in the seat 1 and the body side portion 11 such as a door and a pillar in the vehicle. It is expanded and expanded from (left side of FIG. 3) to the front (right side of FIG. 3). The airbag 3 that expands and expands in this way protects the occupant in the event of a side collision of the vehicle. The white arrows in FIG. 3 indicate the direction in which the impact is applied when the impact is applied to the body side portion 11 due to the side collision of the vehicle.

Next, the airbag 3 will be described in detail.
4 (a) and 4 (b) show a state in which the airbag 3 when deployed and inflated is viewed from the inside in the width direction of the vehicle and a state in which the airbag 3 is viewed from the outside in the same width direction, respectively. .. In the airbag 3, one piece of cloth 13 is folded in two along the fold line L1 and overlapped in the thickness direction (direction orthogonal to the paper surface of FIG. 4), and the peripheral edges of the overlapped portions are overlapped with each other by a thick broken line. It is formed in a bag shape by joining to each other at the position indicated by L2. An opening 14 that communicates the inside and outside of the airbag 3 is formed in a portion (a portion other than the thick broken line L2) where the cloth pieces 13 are not joined to each other in the upper part of the airbag 3 and in the vicinity of the folding line L1. Has been done. Then, the retainer 5 (inflator 4) can be inserted into the inside of the airbag 3 through the opening 14.

Further, it is one of the portions of the cloth piece 13 that are folded in two at the fold line L1 and overlapped in the thickness direction (the one located inside in the width direction of the vehicle), and is the lower side of the opening 14. A pair of upper and lower mounting holes 15 are formed in the portion located at. These mounting holes 15 are for mounting the rear end portion (left end portion of FIG. 4B) of the airbag 3 to the frame 6 (FIG. 2) of the seat back 2. That is, with the retainer 5 inserted inside the airbag 3, the bolt 7 for fixing the retainer 5 to the frame 6 (FIG. 2) is the mounting hole 15 of the cloth piece 13 (FIG. 4 (a)). The airbag 3 is fixed to the frame 6 together with the retainer 5 by using the bolt 7 and the nut 8 (FIG. 2). The fixing of the airbag 3 to the frame 6 is performed so that the portion of the airbag 3 away from the retainer 5 is located on the front side (right side of FIG. 4B) of the vehicle.

A non-expanding portion 16 that does not expand due to the supply of gas from the inflator 4 is formed in the central portion of the airbag 3 in the front-rear direction of the airbag 3 when it is deployed and expanded. Specifically, the central portion of the cloth pieces 13 folded in two along the fold line L1 and stacked in the thickness direction in the front-rear direction of the vehicle is shown in FIGS. 4 (a) and 4 (b). As shown by L3, the parts are joined in an annular shape, and the portion surrounded by the parts joined in the annular shape is referred to as the non-expanding portion 16. By providing the non-expanding portion 16 in the airbag 3 in this way, the amount of expansion gas required to properly deploy and inflate the airbag 3 is reduced, so that the inflator 4 is miniaturized to the side. The weight of the airbag device can be reduced.

On the inner surface (surface of FIG. 4A) of the airbag 3 (cloth piece 13) in the width direction of the vehicle, the position corresponding to the non-expandable portion 16 is located in the substantially front-rear direction (FIG. 4A). A band-shaped tether 17 extending in the left-right direction of FIG. 4B) is provided. As shown in FIG. 4A, the front portion 17a of the tether 17 is joined to the front portion of the airbag 3, more specifically, to the front peripheral edge at the position indicated by the thick broken line L2. Further, the rear end portion 17b of the tether 17 is joined to the rear portion of the airbag 3, more specifically, the portion of the cloth piece 13 in which the mounting hole 15 is formed.

A connecting hole 18 through which a bolt 7 for fixing the retainer 5 to the frame 6 (FIG. 2) is passed is formed in the rear end portion 17b of the tether 17. Then, under the state where the bolt 7 is passed through the connecting hole 18 and the mounting hole 15 of the cloth piece 13, the retainer 5 is fixed to the frame 6 with the bolt 7 and the nut 8 to fix the retainer 5 to the rear end of the tether 17. The portion 17b is joined to the rear portion (rear end portion) of the airbag 3.

In the tether 17, the length between the front portion 17a and the rear end portion 17b joined to the airbag 3 is such that the portion of the airbag 3 to which the front portion 17a is joined and the rear end portion 17b are joined. It is shorter than the length between the parts to be made. Note that FIG. 5 schematically shows a state in which the airbag 3 in FIG. 4B is expanded and inflated, and the airbag 3 is viewed from the direction of arrows AA. As can be seen from FIG. 5, when the airbag 3 is expanded and expanded, the tether 17 located corresponding to the non-expanding portion 16 receives tension based on the expansion and expansion of the airbag 3.

This is because, in the tether 17, the length between the front end portion 17a and the rear end portion 17b joined to the airbag 3 is set as described above. As described above, the tether 17 that receives tension based on the expansion and deployment of the airbag 3 is provided for the purpose of maintaining the occupant protection function in the airbag 3 forming the non-expandable portion 16. That is, by applying tension to the tether 17 as described above, the occupant P1 (FIG. 1) is protected by the tether 17 at the portion corresponding to the non-expanding portion 16 in the airbag 3.

As shown in FIG. 4A, in the tether 17, a fragile portion that is vulnerable to other portions on the front side of the vehicle than the front portion 17a joined to the front peripheral edge of the airbag 3 A band portion 17c having 19 is formed. Specifically, the fragile portion 19 is formed in the portion of the band portion 17c in which the notch 21 is made by making a notch 21 in the band portion 17c. Further, a connecting hole 22 through which a bolt 7 for fixing the retainer 5 to the frame 6 (FIG. 2) is passed is formed on the front side of the band portion 17c in front of the fragile portion 19. Then, under the state that the bolt 7 is passed through the connecting hole 22 and the mounting hole 15 of the cloth piece 13, the retainer 5 is fixed to the frame 6 with the bolt 7 and the nut 8, so that the tether 17 (band portion) is used. The front end portion 17d of 17c) is also fixed to the frame 6.

6 and 7 show the folded state in which the airbag 3 is stored together with the retainer 5 (inflator 4) in the seat back 2 (FIG. 2), and the folded airbag 3 shown in FIG. 6 is indicated by an arrow. The state seen from the BB direction is shown. As can be seen from these figures, the folded state of the airbag 3 is held by the tether 17. Specifically, the tether 17 is wound around the folded airbag 3 and temporarily fixed, so that the folding of the airbag 3 is maintained. In the airbag 3 at this time, the portion between the portion where the front portion 17a of the tether 17 is joined and the portion where the rear end portion 17b of the tether 17 is joined is folded so as to be shortened in the front-rear direction of the vehicle. The tether 17 is wound around the folded portion and temporarily fixed, so that the folded portion of the above portion is maintained.

As shown in FIG. 7, in the tether 17 wound around the folded airbag 3, the retainer 5 (inflator 4) is fixed to the frame 6 (FIG. 2) in the connecting hole 22 of the band portion 17c. Bolt 7 is passed through. Further, when the tether 17 is wound around the folded portion of the airbag 3, the portion between the front portion 17a and the rear end portion 17b joined to the airbag 3 in the tether 17 is the same. A locking portion 23 for locking the tether 17 with a slack is provided. The locking portion 23 is realized by a tear seam formed by stitching together the slackened portions of the tether 17 so that the tether 17 has slack and the slack is not eliminated.

The airbag 3 held in the folded state is housed in the seat back 2 (FIG. 2) and is fixed to the frame 6 of the seat back 2 by using bolts 7 and nuts 8. Then, when the airbag 3 is fixed to the frame 6 in this way, the front end portion 17d of the band portion 17c provided with the fragile portion 19 in the tether 17 is also fixed to the frame 6, whereby the tether 17 is around the airbag 3. It is temporarily fixed while being wrapped around.

Next, the operation of the side airbag device will be described.
When the gas from the inflator 4 is supplied to the airbag 3 held in the folded state by the tether 17, the airbag 3 is expanded and expanded accordingly, and the airbag 3 is wound so as to surround the periphery of the airbag 3. The fragile portion 19 of the band portion 17c in the tether 17 is cut. As a result, the temporary fixing of the tether 17 while being wound around the airbag 3 is released, so that the tether 17 does not hinder the deployment and expansion of the airbag 3.

Further, when the airbag 3 is deployed and expanded, the locking at the locking portion 23 of the tether 17 is released accordingly. Specifically, the stitching of the tear seams forming the locking portion 23 is released as the airbag 3 expands and expands, so that the slackening of the tether 17 due to the tear seams is eliminated. As a result, tension acts on the tether 17 based on the expansion and deployment of the airbag 3 shown in FIG. 7.

The tether 17 is provided to maintain the occupant protection function of the airbag 3 when the non-expandable portion 16 is formed in the airbag 3 with the intention of reducing the weight of the side airbag device. For this reason, by using the tether 17 provided in the airbag 3 to hold the fold of the airbag 3 that is folded at the time of storage, it is necessary to newly add parts such as a wrapping cloth for holding the fold. Will disappear.

According to the present embodiment described in detail above, the following effects can be obtained.
(1) It is possible to suppress an increase in the number of parts in the side airbag device.
(2) When the airbag 3 held in the folded state is expanded and expanded, the band portion 17c of the tether 17 wound around the airbag 3 is cut by the fragile portion 19. As a result, the temporary fixing of the airbag 3 while holding the fold of the airbag 3 by the tether 17 is released.

(3) When the tether 17 is wound around the folded airbag 3, even if there is an excess in the tether 17 in realizing the winding, the tether 17 is loosened due to the slack in the locking portion 23. It can be suppressed by adjusting the amount of slack. Then, when the airbag 3 is expanded and expanded through the supply of gas from the inflator 4 to the folded airbag 3, the locking at the locking portion 23 is released along with the expansion and expansion, and the tether 17 is released. It becomes possible to apply tension based on the expansion and deployment of the airbag 3 to the airbag 3.

The above embodiment can be changed as follows, for example.
-Although the tear seam is exemplified as the locking portion 23 of the tether 17, other than that may be adopted.

-If there is no excess in the tether 17 wound around the folded airbag 3, it is not necessary to provide the locking portion 23 on the tether 17.
-The fragile portion 19 formed in the band portion 17c of the tether 17 is formed by making a notch in the band portion 17c, but it does not necessarily have to be formed in that way. For example, a portion in which the band portion 17c is thinned may be designated as a fragile portion 19, or a portion in which the fiber density is reduced may be designated as a fragile portion 19 when the band portion 17c is formed of fibers.

-In the tether 17, a rear portion other than the rear end portion 17b may be joined to the rear portion of the airbag 3.

1 ... Seat, 2 ... Seat back, 3 ... Airbag, 4 ... Inflator, 5 ... Retainer, 6 ... Frame, 7 ... Bolt, 8 ... Nut, 9 ... Control device, 10 ... Impact sensor, 11 ... Body side part, 13 ... cloth piece, 14 ... opening, 15 ... mounting hole, 16 ... non-expanding part, 17 ... tether, 17a ... front part, 17b ... rear end part, 17c ... band part, 17d ... front end part, 18 ... connecting hole , 19 ... fragile part, 21 ... notch, 22 ... connecting hole, 23 ... locking part.

Claims (3)

By supplying gas from the inflator to the folded and stored airbag, the airbag is placed between the occupant seated in the seat of the vehicle and the body side portion of the vehicle from the rear to the front of the vehicle. In a side airbag device that deploys and inflates towards
A non-expandable portion that does not expand due to the supply of gas from the inflator is formed in the central portion of the airbag in the expanded and expanded state in the front-rear direction of the vehicle.
At a position inside the width direction of the vehicle in the airbag when deployed and inflated and corresponding to the non-expanded portion, the front portion extends in the front-rear direction of the vehicle and is joined to the front portion of the airbag. At the same time, a tether is provided in which the rear part is joined to the rear part of the airbag.
The length between the front and rear parts of the tether that are joined to the airbag is greater than the length between the front and rear parts of the tether that are joined to the airbag. Is also shortened,
The airbag is folded so that the portion between the portion where the front portion of the tether is joined and the portion where the rear portion of the tether is joined is shortened in the front-rear direction of the vehicle, and the folded portion. A side airbag device, characterized in that the tether is wound around the tether and temporarily fixed so that the portion is stored in a folded state. The airbag is stored in a folded state in the seat back of the seat, and the rear portion of the vehicle in the front-rear direction under the expanded and inflated state of the airbag is the frame of the seat back. Is fixed to
In the tether, a band portion having a fragile portion, which is a fragile portion, is formed on the front side of the vehicle with respect to the front portion joined to the airbag.
The tether is wound around a folded portion of the airbag, and by fixing the band portion to the frame of the seat back, temporary fixing while holding the folded portion of the portion is realized. The side airbag device according to claim 1. The portion of the tether between the front and the rear that is joined to the airbag is provided with slack when the tether is wrapped around the folded portion of the airbag. The side airbag device according to claim 1 or 2, wherein a locking portion that locks in a closed state is provided.

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