JP3816656B2 - Airbag device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an airbag device in which a suspension string (tether) is provided between a front base fabric and a back base fabric of an airbag main body so that the airbag main body is inflated and deployed into a predetermined shape.
[0002]
[Prior art]
2. Description of the Related Art Conventionally, airbag devices having various structures have been proposed and put into practical use as airbag devices that are mounted on automobiles and protect passengers in the event of a collision.
[0003]
For example, the one described in Japanese Patent Application Laid-Open No. 6-72267 restricts the front base fabric from inflating greatly toward the occupant side between the front base fabric and the rear base fabric of the airbag body. A suspension belt is provided, the length of the suspension belt is made larger than the width of the airbag body when it is inflated, and the middle portion of the belt portion formed long is subjected to hand stitching. Since it can be easily performed, the workability is improved.
[0004]
Japanese Patent Application Laid-Open No. 7-304411 discloses that between the suspension belt member to which the inflator is attached and the belt catch provided in front of the belt catch in order to easily and quickly perform the sewing operation between the belt catch and the tip of the suspension belt. When connecting with a plurality of suspension belt members, the positioning pin is inserted into the tip of the belt part and the belt catch that sandwiches the belt part in the vertical direction, and then the air is sewn between the belt part and the belt catch. A method for manufacturing the bag body is described.
[0005]
[Problems to be solved by the invention]
In any of the above conventional airbag devices, when an impact due to a collision is detected, the inflator instantaneously generates a large amount of gas, inflates the airbag body, and protects the occupant from the impact due to the collision. .
[0006]
However, in recent years, a combustion type inflator has been adopted in which the gas generation capacity is less likely to deteriorate even after a long period of time.
[0007]
Since this combustion-type inflator also generates heat when gas is generated, the gas generated from the inflator is directly sent into the airbag body to inflate and deploy the airbag body as in the conventional airbag device. In this case, the airbag base fabric near the insulator receives heat.
[0008]
In particular, in a side-impact airbag device in which a tether (suspending belt) that regulates the expansion of the airbag body in the width direction is provided in front of the inflator, the high-temperature gas directly hits the sewing portion of the airbag body and the tether. The sewn part receives heat.
[0009]
In view of this point, a separate cloth is applied to the sewing part of the airbag and the tether to reinforce the sewing part, or a flameproof cloth is provided in front of the inflator so that the high-temperature gas ejected from the inflator Measures are taken to prevent it from hitting the sewn part, but these methods increase the number of parts and require time and labor, which increases costs and increases the volume when the airbag body is folded. Therefore, there is a problem that the airbag device becomes large.
[0010]
The present invention has been made to remedy such a conventional problem, and provides an airbag device in which a protective cloth for preventing gas ejected from an inflator from directly hitting a sewn portion of a tether is provided integrally with the tether. Thus, it is intended to prevent the tether sewn part from being damaged by heat damage.
[0011]
[Means for Solving the Problems]
In order to achieve the above object, the present invention provides a protective piece that covers the tethered seam portion of the tether that is turned over when the gas of the inflator hits both ends of the tether that restricts the airbag body from expanding in the width direction. The high-temperature gas blown from the inflator is prevented from directly hitting the tether sewn part, and the tether sewn part will not be damaged by heat damage. Will be able to.
[0012]
DETAILED DESCRIPTION OF THE INVENTION
The present invention according to claim 1 is an airbag main body formed in a bag shape, an inflator provided in the airbag main body, and inflating and deploying the airbag main body by injecting gas when an impact is detected, A tether that connects the front base fabric and the back base fabric of the airbag body to inflate and deploy the airbag body into a predetermined shape, and the both ends of the tether are integrally extended to form an expansion of the airbag body. A pair of protective pieces that cover the tethered seam when unfolded, and the protective piece is turned up by the gas pressure ejected by the inflator with the leading end as a free end to cover the sewn part of the tether. It is comprised as follows.
[0013]
With the above configuration, when high-temperature gas is ejected from the inflator toward the tether due to the impact at the time of the collision, the protective cloth continuously provided at the end of the tether is turned up by the gas pressure to cover the sewn portion of the tether. There is no fear that the sewn part is damaged by heat damage due to the high-temperature gas.
[0014]
As a result, the airbag body is inflated and deployed in a predetermined shape instantly, so that the occupant can be reliably protected from the impact at the time of collision.
[0015]
The present invention according to claim 2 is such that the width of the protective piece is larger than the width of the tether.
[0016]
With the above configuration, it is possible to reliably prevent the hot gas from the inflator from directly hitting the sewn portion of the tether.
[0018]
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
[0019]
1 and 2 show a driver airbag device mounted on a steering handle or the like, and an airbag formed into a bag shape by sewing around the front base fabric 1a and the back base fabric 1b. It has a main body 1.
[0020]
On the inner surface of the back base fabric 1 b of the airbag body 1, there is a substantially circular reinforcing cloth 2 with a mounting portion 2 a integrally projecting at an opposing position, and a circular reinforcing cloth 3 at the center of the reinforcing cloth 2. Sewn.
[0021]
An attachment hole 3a that penetrates to the back base cloth 1b is opened at the center of the reinforcing cloth 3, and the inflator 4 is attached to the attachment hole 3a from the lower surface side of the back base cloth 1b.
[0022]
The inflator 4 has a cylindrical portion 4b in which a plurality of ejection holes 4a are opened on the peripheral surface, and the cylindrical portion 4b protrudes into the airbag body 1 from the upper surface of the reinforcing cloth 3, When a sensor (not shown) senses the impact at that time, hot gas is ejected into the airbag body 1 from the ejection hole 4a, and the airbag body 1 is inflated and deployed instantaneously.
[0023]
Further, between the front base fabric 1a and the back base fabric 1b of the airbag main body 1, the airbag main body 1 is restricted from expanding in the width direction, and the tether 6 is inflated and deployed to a predetermined shape. Is provided.
[0024]
The tether 6 is formed in a band shape with a base fabric made of the same material as the airbag body 1, and wide protective pieces 6 a are formed integrally with the tether 6 at both ends. The vicinity of the boundary is sewn in a loop shape with a sewing thread 5 to the attachment portion 2a of the reinforcing cloth 2.
[0025]
The tip of the protective piece 6a extends to the cylindrical portion 4b side of the inflator 4, and when the airbag body 1 is folded, it is in close contact with the upper surface of the reinforcing cloth 2 as shown in FIG. When a high-temperature gas is ejected from the ejection hole 4a of the inflator 4, the tip is turned by the pressure of the gas so as to cover the upper surface of the sewing portion as shown in FIG.
[0026]
On the other hand, a circular wide portion 6b is formed at an intermediate portion of the tether 6, and the wide portion 6b is sewn to the front base fabric 1a in a state of being in close contact with the inner surface of the front base fabric 1a.
[0027]
Next, the operation of the airbag device configured as described above will be described.
[0028]
The airbag main body 1 is mounted in the steering handle together with the inflator 4 in a folded state. When a sensor (not shown) detects an impact caused by a collision, high-temperature gas is injected into the airbag main body 1 from the ejection hole 4a of the inflator 4. The airbag body 1 is inflated and deployed.
[0029]
Then, the protection piece 6a at the end of the tether 6 that has been folded up so far on the upper surface of the reinforcing cloth 3 is turned up by the high-temperature gas as shown in FIG. Since the sewing thread 5 sewn on the second attachment portion 2a is covered, it is possible to prevent the hot gas from directly hitting the sewing thread 5.
[0030]
As a result, the sewn portion of the tether 6 does not receive heat, so that the airbag body 1 can be instantly inflated and deployed into a predetermined shape while restricting the expansion of the airbag body 1 in the width direction. The driver can be reliably protected from.
[0031]
In addition, although the said embodiment is a case of the airbag apparatus for drivers | operators, it can be applied also to the airbag apparatus for side collision which protects a passenger | crew from a side collision.
[0032]
Next, an embodiment of the side airbag device will be described in detail with reference to the drawings shown in FIGS.
[0033]
In the airbag body provided in FIG 10 is the side airbag apparatus, a main bag portion 10 ₁ for protecting a side collision the occupant's chest, the sub-bag unit 10 ₂ to protect an occupant's head integral It has a structured structure, and is formed into a bag shape by sewing the periphery of the front base fabric 10a and the back base fabric 10b so as to expand and develop into a predetermined shape by the gas generated from the inflator 14.
[0034]
And with the inflator 14 to the main bag portion 10 ₁ is attached to the air bag case so as to be positioned (not shown), a main bag portion 10 _1, the boundary of the sub-bag unit 10 _2, the partition wall 10c There have been formed, to the partition wall 10c, are formed communication holes 10d communicating between the main bag portion 10 ₁ and the sub bag portion 10 _2.
[0035]
The communicating hole 10d is inflated by gas generated from the inflator 14 to regulate the flow into the sub bag 10 in _2, is first inflated and deployed a main bag portion 10 _1, then the sub-bag unit 10 ₂ It is intended to be deployed and is formed by an orifice.
[0036]
On the other hand, in the airbag main body 10, the airbag main body 10 ₁ and the subbag 102 ₂ are inflated and deployed instantaneously along the gap between the door 16 and the seat back 17 during inflation and deployment. A plurality of tethers 12 for restricting the expansion in the width direction are provided.
[0037]
As shown in FIG. 6, the tether 12 is formed in a band shape by a base fabric made of the same material as that of the airbag body 10, and both end sides thereof are a front base fabric 10a of the airbag body 10 and a back base fabric 10b by sewing threads 13. Is sewn on the inside.
[0038]
Further, the tether 12 provided in front of the inflator 14 is directly hit by the high-temperature gas ejected from the inflator 14, and the tether 12 and the sewing thread 13 are thermally damaged. To prevent this, the length of the tether 12 is increased. The airbag body 10 is formed to have a length approximately twice the width when deployed, and this extended portion is used as a protection piece 12a, and is folded in a loop as shown in FIG. 6 to the front of the tether 12, that is, to the inflator 14 side. ing.
[0039]
These protective pieces 12a are formed in advance wider than the vertical width of the tether 12 so that the hot gas from the inflator 14 does not directly hit the sewn portion of the tether 12, and the end portions of the protective pieces 12a are In a state of being overlapped with each other, a sewing thread 15 is sewn to the center of the front surface of the tether 12.
[0040]
Next, the operation of the side impact airbag apparatus configured as described above will be described.
[0041]
During normal times, the airbag body 10 is housed in a folded state in an airbag case embedded in the upper part of the side surface of the seat back 17. In this state, when a sensor (not shown) detects an impact caused by a side collision, the inflator 14 a large amount of gas is generated from, is ejected toward the tether 12 as shown in FIG. 7, the main bag portion 10 ₁ of the airbag body 10 starts the expansion, on the front side of the inflator 14, the protective piece 12a Is folded in a loop shape, the high-temperature gas directly hits the protective piece 12a and does not hit the sewing thread 13 that is sewn to the airbag body 10.
[0042]
This order has never sewn portion of the tether 12 may be damaged by heat damage, to regulate the expansion of the width direction of the main bag portion 10 _1, the main bag portion 10 along the gap between the door 16 and the seat back with ₁ is quickly inflated and deployed, the gas is expanded deployed main bag portion 10 _1, and flows from the communication hole 10d into the sub-bag unit 10 _2, the sub-bag unit 10 ₂ as shown in FIG. 8 Inflate and deploy.
[0043]
The first main bag portion 10 ₁ protects the occupant's chest from an impact of a side collision, followed in order to protect an occupant's head by the sub-bag unit 10 _2, to reliably protect an occupant from an impact of a side collision Will be able to.
[0044]
Further, since the end portion of the protection piece 12a is sewn to the center of the front surface of the tether 12, the sewn portion of the tether 12 can be reliably protected without being twisted by the high temperature gas.
[0045]
In the above embodiment, the end of the protective piece 12a is sewed on the tether 12, but the end of the protective piece 12a is separately sewn on the front surface of the tether 12 as shown in FIG. As shown in FIG. 10, the same effect can be obtained by sewing the end portions of the protective pieces 12a together.
[0046]
【The invention's effect】
As described in detail above, the present invention has an airbag body in which protective pieces are extended and formed at both ends of a tether that regulates expansion of the front and back base fabrics constituting the airbag body in the separating direction. Since the protective portion covers the sewn portion of the tether during the expansion and expansion of the tether, the sewn portion of the tether can be prevented from receiving heat.
[0047]
As a result, the airbag main body is inflated and deployed in a predetermined shape, so that the occupant can be reliably protected from impact by collision.
[0048]
In addition, since the protective piece is wider than the tether, it is possible to reliably prevent the high-temperature gas ejected from the inflator from directly hitting the tether sewn part and to sew a separate fabric to the tether sewn part. Therefore, since the number of parts and the number of man-hours required for the sewing work can be reduced, the cost of the airbag apparatus can be reduced.
[Brief description of the drawings]
FIG. 1 is an exploded perspective view of a tether provided in an airbag body of an airbag device according to an embodiment of the present invention.
FIG. 2 is a perspective view of the vicinity of the inflator provided in the airbag body of the airbag apparatus according to the embodiment of the present invention.
FIG. 3 is a cross-sectional view of an airbag device according to an embodiment of the present invention.
FIG. 4 is an operation explanatory view of the airbag device according to the embodiment of the present invention.
FIG. 5 is a development view of an airbag main body provided in a side collision airbag apparatus according to another embodiment of the present invention.
FIG. 6 is a perspective view of the vicinity of a tether of an airbag main body provided in a side-impact airbag device according to another embodiment of the present invention.
FIG. 7 is an operation explanatory view of a side-impact airbag device according to another embodiment of the present invention.
FIG. 8 is an operation explanatory view of a side-impact airbag device according to another embodiment of the present invention.
FIG. 9 is an explanatory view showing a modification of the protective piece of the airbag device according to the embodiment of the present invention.
FIG. 10 is an explanatory view showing a modification of the protective piece of the airbag device according to the embodiment of the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Airbag main body 1a Front base cloth 1b Back base cloth 2 Reinforcement cloth 2a Attachment part 3 Reinforcement cloth 3a Attachment hole 4 Inflator 4a Ejection hole 5 Sewing thread 6 Tether 6a Protection piece 10 Airbag body 10 ₁ Main bag part 10 ₂ Subbag Part 10a Front base fabric 10b Back base fabric 10c Partition wall 10d Communication hole 12 Tether 12a Protection piece 13 Sewing thread 14 Inflator 15 Sewing thread 16 Door 17 Seat back

Claims (2)

An airbag main body formed in a bag shape, an inflator provided in the airbag main body and inflating and deploying the airbag main body by injecting gas when an impact is detected; and a surface base fabric of the airbag main body; A tether that connects the back base fabric to inflate and deploy the airbag body into a predetermined shape, and both ends of the tether extend integrally to form a sewn portion of the tether when the airbag body is inflated and deployed. A pair of protective pieces covering the air , wherein the protective piece is turned up by the gas pressure ejected by the inflator with its tip end as a free end so as to cover the sewn portion of the tether. Bag device.   The airbag device according to claim 1, wherein the width of the protective piece is larger than the width of the tether.

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