JP3922764B2 - Airbag - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to airbags that bulges deployed by the inflow of gas.
[0002]
[Prior art]
Conventionally, for example, an airbag device (airbag module) that protects an occupant with respect to, for example, a steering wheel of an automobile, an instrument panel that faces an occupant in the front passenger seat, or a back portion of a front seat that faces an occupant in the rear seat Is provided. For example, as shown in FIG. 11, the airbag apparatus 1 for a steering wheel is folded so as to cover a base plate 2 fixed to the steering wheel body, an inflator fixed to the base plate 2, and the inflator. The bag-like airbag 4 stored in the housing, the cover body 5 that covers the airbag 4 and is attached to the base plate 2, and a control device that operates the inflator, and the like. And this airbag apparatus 1 starts an inflator in the state which the collision of the vehicle detected by the control apparatus, discharge | releases gas into the inside of the airbag 4 from this inflator, and expands and deploys the airbag 4. FIG. Then, by the pressure of inflation of the airbag 4 by the gas, the cover body 5 is cleaved at a predetermined tear line to form a projecting port 6, and the airbag 4 is inflated and deployed from the projecting port 6 to the occupant side. Is restrained to relieve the impact on the passenger. Further, as shown in FIG. 12, the airbag 4 of the airbag apparatus 1 provided in the steering wheel as described above is formed into a bag shape by stitching the outer peripheral portions of two base cloths 4a and 4b having a substantially circular plane shape. The so-called two-piece bag can be sewn on a flat surface and is easy to manufacture.
[0003]
On the other hand, in the airbag device for the passenger seat and the airbag device for the rear seat, as shown in FIG. 13, between the mounted portion 7 such as an instrument panel provided with the airbag device 1 and the position of the occupant , And a large bulge dimension in the occupant direction, that is, a stroke, is ensured. And in order to ensure sufficient stroke and the restraint performance with the limited output of the inflator, the airbag 4 is formed in a substantially cubic bag shape having side surfaces.
[0004]
However, the substantially cubic bag-like shape requires a large number of base fabrics and an operation for sewing these base fabrics, and has a problem that it is difficult to reduce the manufacturing cost.
[0005]
In this regard, for example, a configuration described in JP-A-8-175304 is known. And in this structure, it aims at obtaining a desired deployment shape by picking and sewing the part which opposes the passenger | crew of an airbag.
[0006]
However, in the configuration described in this publication, three-dimensional sewing is required, and the volume of the airbag is reduced by picking and sewing the airbag, so that the base fabric is wasted and it is difficult to reduce the manufacturing cost. I have a problem. Furthermore, since the portions sewn and sewn are relatively harder than other portions, there is a problem that it is not easy to improve the effect of buffering the impact.
[0007]
[Problems to be solved by the invention]
As described above, the configuration in which two base fabrics are sewn on a plane has a problem that it is difficult to increase the stroke at the time of bulging and unfolding. In addition, as described in JP-A-8-175304, in the configuration in which the portion of the airbag facing the occupant is sewn and sewn, three-dimensional sewing is required, and the air bag is sewn and sewn. Since the volume of the bag is reduced, the base fabric is wasted, and it is difficult to reduce the manufacturing cost, and the parts sewn and sewn are relatively harder than the other parts, so that the impact is buffered. There is a problem that improvement is not easy.
[0008]
The present invention has been made in view of the above problems, with the bulge size when swollen greater can be secured, and an object thereof is to provide a airbags that manufacturing cost can be reduced.
[0009]
[Means for Solving the Problems]
The airbag according to claim 1 is a bag-like airbag in which gas flows in and inflates and expands in a predetermined bulging direction, and includes a first base fabric and the bulge of the first base fabric. A first folded portion provided on the first base fabric, and a folding line of the first folded portion provided on the second base fabric. The first and second base fabrics are formed by folding each folded portion into a plane shape substantially the same as the other, and stitched to form a bag shape. It has been done.
[0010]
In this configuration, when the airbag is inflated, the folded-back portion expands as a gusset so that the bulge dimension in the bulge direction is easily set large. Further, since the first and second base fabrics are stitched with substantially the same planar shape, the stitching operation is facilitated and the manufacturing cost is reduced. Furthermore, the bulging dimension is easily increased by providing the folded portion on each base fabric. Further, by arranging the folded portions so that the folding lines cross each other, the overlap of the folded portions in the stitched portion is reduced or eliminated, and the workability at the time of stitching and the strength of the stitched portion are easily improved.
[0011]
Airbag according to claim 2, wherein, in the airbag according to claim 1 Symbol placement, turned-back portion are those folded is folded substantially parallel pair of fold lines.
[0012]
In this configuration, the folded portion has a substantially Z-shaped cross section, whereby the thickness dimension of the airbag is reduced, and the bulk when the airbag is folded is easily reduced.
[0013]
According to a third aspect of the present invention, in the airbag according to the first or second aspect , the folded portion is constrained so as to be ruptured by a gas inflow pressure at the time of inflation.
[0014]
And in this structure, the expansion | deployment to the side at the time of expansion | swelling of an airbag is controlled in multiple steps within a predetermined dimension, and the expansion | swelling dimension to an expansion | swelling direction is easily set large.
[0015]
DETAILED DESCRIPTION OF THE INVENTION
DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an embodiment as a premise of an airbag according to the present invention will be described with reference to the drawings.
[0016]
1 to 4, 11 is an airbag. As shown in FIG. 11, the airbag 11 is provided in a steering wheel of an automobile to protect the driver. As shown in FIG. It is provided in an instrument panel and used in an airbag device that protects a passenger in a passenger seat or an airbag device that is provided in the back of a front seat and protects a passenger in a rear seat. For example, as shown in FIG. 11, with respect to the airbag device provided in the steering wheel, a base plate 2 fixed to the steering wheel main body, a substantially cylindrical inflator fixed to the base plate, and the inflator are covered. A bag-like airbag 11 that is folded and stored, a cover body 5 that covers the airbag 11 and is attached to the base plate 2, a control device that operates the inflator, and the like. And this airbag apparatus 1 starts an inflator in the state which the control apparatus detected the collision of the vehicle, discharge | releases gas into the inside of the airbag 11 from this inflator, and expands and deploys the airbag 11. FIG. Then, by the pressure of inflation of the airbag 11 by the gas, the cover body 5 is cleaved at a predetermined tear line to form a projecting port 6, and the airbag 11 is inflated and deployed from the projecting port 6 to the occupant side. Is restrained to relieve the impact on the passenger.
[0017]
Hereinafter, the bulging direction side, which is the occupant side, will be described as the upper side, and the vehicle body side as the lower side.
[0018]
As shown in FIGS. 1 to 4, the airbag 11 has an upper base fabric 21 as a second base fabric and a lower base fabric 22 as a first base fabric stacked one above the other. The outer peripheral portion is stitched with a sewing means 23 such as a thread to form a bag shape. The upper base fabric 21 has a planar circular shape, while the lower base fabric 22 is folded at predetermined four folding lines a, b, c, d, and three base fabrics are stacked. It is formed in the same circular shape as the upper base fabric 21 with the folded portions 25, 25 having a substantially Z-shaped cross section formed in two places. That is, the lower base fabric 22 is formed so that its outer shape is larger than that of the upper base fabric 21 in a state where the lower base fabric 22 is developed on a plane. The folding lines a, b, c, and d are formed in a straight line that is parallel to each other and reaches from one edge of the lower base fabric 22 to the other edge. Further, a circular gas inlet 27 is formed at the center of the lower base fabric 22, and the inflator gas is allowed to flow in. The outer periphery of the gas inlet 27 is A mounting portion 28 is formed, and a plurality of mounting holes 29 are formed in the mounting portion 28.
[0019]
In the airbag 11, a mounting portion 28 is sandwiched between an annular retainer disposed inside the airbag 11 and the base plate 2, and fixing bolts protruding from the retainer are inserted into the mounting holes 29. The base plate 2 is fixed to the base plate 2 by tightening with a nut from the lower side. Then, it is folded into a predetermined shape and stored inside the cover body 5.
[0020]
Next, the manufacturing process of the airbag 11 will be described.
[0021]
First, the upper base fabric 21 is cut into a circular shape, and the lower base fabric 22 is formed in a predetermined shape larger than the upper base fabric 21.
[0022]
Then, the upper base fabric 21 is spread and placed, and the lower base fabric 22 having the same outer shape as the upper base fabric 21 is folded on each of the folding lines a, b, c and d. Put.
[0023]
In this state, the outer peripheral portions of the upper base fabric 21 and the lower base fabric 22 are stitched together, and the front and back are reversed, whereby the bag-like airbag 11 is completed.
[0024]
And according to the airbag 11 of this Embodiment, it is what is called a 2 piece bag which consists of the two base fabrics 21 and 22, and while the number of parts is small, these base fabrics 21 and 22 are substantially the same planar shape. The sewing work can be performed on a flat surface. Therefore, the suturing operation is facilitated, automation by a machine can be facilitated, and the manufacturing cost can be reduced.
[0025]
Further, when the gas flows into the airbag 11 and swells, as shown in FIGS. 2 and 3, the folded portions 25 and 25 are expanded, and the expanded portion 41 spreads out as a town. With respect to the developed shape 42, the bulging direction, that is, the bulging dimension toward the occupant, that is, the stroke can be easily set large. Therefore, for example, it is possible to provide a highly restrictive airbag 11 suitable for an airbag device for a passenger on the passenger seat and an airbag device for a passenger on the rear seat.
[0026]
Further, since the upper base fabric 21 is not provided with the folded portion, and the folded portion 25 is provided only on the lower base fabric 22, the upper base fabric 21 can be easily secured and the buffering effect can be easily improved. At the same time, the upper base fabric 21 can be used as a base fabric at the time of sewing work, and the lower base fabric 22 folded on the upper base fabric 21 can be placed on the work, thereby improving workability. Further, since the lower base fabric 22 can ensure a larger stroke than the diameter dimension at the time of deployment, there is a structure such as the cover body 5 around the mounting portion 28 so that the diameter dimension at the time of deployment can be reduced. Even in this case, the cover body 5 can be smoothly inflated and deployed, the capacity of the airbag 11 can be used effectively, the tension applied to the portion to be squeezed can be reduced, and the load applied to the mounting portion 28 can be reduced. This can be reduced, and the mounting structure can be simplified.
[0027]
Further, the outer shape of the airbag 11 is the same as that of a general airbag for a conventional steering wheel, and the shape of the folded portion 25 of the airbag 11 is held by sewing, and in particular, two parallel folding lines. Since it is folded back into a substantially Z shape at a, b, c, and d, it is possible to facilitate the folding work for storing in the airbag device, and it is possible to reduce the bulk in the folded state.
[0028]
In the above embodiment, as shown in FIG. 4, after the upper base fabric 21 and the lower base fabric 22 are stitched together, the front and back are reversed, and the outer peripheral edges of the base fabrics 21 and 22 are airbags. However, as shown in FIG. 5, the upper and lower base fabrics 21 and 22 are sewn together and the front and back sides are not reversed, so that the number of man-hours can be reduced and the manufacturing cost can be reduced.
[0029]
Further, the folding line and the folding part of the airbag can take various numbers and arrangement patterns, and by changing the arrangement of the folding line and the folding part, air bags having various deployment shapes or capacities with almost the same outer shape. A bag can be manufactured and manufacturing cost can be reduced.
[0030]
In the embodiment of the present invention , not only the folded portions 25, 25 as the first folded portions are formed on the lower base fabric 22, as in the airbag 11 shown in FIG. The cloth 21 can also be folded back along the folding lines a, b, c, d to form the folded portions 25, 25 as the second folded portions, and the stroke can be easily secured. Further, as shown in FIG. 6, the folded portions 25 of the upper and lower base fabrics 21 and 22 can be overlapped with each other at a predetermined angle to reduce overlapping of the folded portions 25 at the stitched portions. Therefore, the workability at the time of stitching and the strength of the stitched portion can be easily improved.
[0031]
Moreover, a deployment shape can also be controlled by the relationship between the direction of the folding line (folded part) of the airbag and the direction of weaving of the base fabric. That is, one base fabric is stretched by the development of the folded portion of the other base fabric. In addition, the base fabric itself is woven by weaving yarns that intersect each other, but there is little elongation in the direction along any of these weaving yarns (yarn direction), and in the direction that intersects any of these weaving yarns (bias direction). Elongation is large and it becomes possible to receive the impact at the time of deployment well. Therefore, it is arranged so that the folded portion of the other base fabric expands along the bias direction of the weave of one base fabric, that is, the bias direction of the weave of one base fabric and the fold line of the other base fabric. By arranging the cloths so as to be substantially orthogonal to each other and stitching the base cloths together, the impact at the time of deployment can be reduced, and a base cloth woven with relatively thin threads can be used. Moreover, the shape after the expansion | deployment of a folding | turning part can also be naturally corrected by the elongation to the bias direction of a base fabric.
[0032]
Further, as shown in FIG. 1 and the like, in addition to forming the folded portions 25 and 25 symmetrically with respect to the center of the lower base fabric 22, for example, four folding lines are arranged on one side of the gas inlet 27. And a pair of folding | returning parts 25 and 25 can also be formed.
[0033]
Further, as shown in FIGS. 7 and 8, the bent hole 44, that is, the exhaust port for the gas that has flowed in, can be formed in the intermediate base cloth sandwiched between the base cloths at each folding portion 25. According to this configuration, at the initial stage of deployment of the airbag 11, the gas injected from the inflator can be made difficult to escape directly from the vent hole 44, and the folded portion 25 is also deployed after the airbag 11 is deployed. Therefore, the exhaust function of the vent hole 45 can be ensured.
[0034]
Further, the folded portion is releasably restrained by a restraining means such as a thread that can be broken by the pressure (tension) of gas inflow during inflation, and the deployment shape of the airbag 11 during inflation is controlled step by step. You can also. For example, with this configuration, the lateral expansion of the airbag 11 when it is inflated can be controlled in multiple stages within a predetermined dimension, and the bulge dimension toward the occupant can be easily set large. Even in this configuration, the outer periphery of the airbag 11 is sewn with a predetermined strength and does not break when the airbag 11 is inflated and deployed. Further, the breakable restraint location is usually set on the inner side of the outer periphery of the airbag 11.
[0035]
And as a configuration for restraining the folded portion, for example, as shown in FIG. 9, the folded portion 25 provided on one base fabric 22 is sewn with a breakable thread 46, that is, a stitch is provided, or As shown in FIG. 10, the folded portion 25 provided on one base fabric 22 can be sewn together with the other base fabric 21 with a breakable breaking thread 46, and these are shown in FIGS. 9 and 10. The configurations can be combined as appropriate.
[0036]
【The invention's effect】
According to the airbag according to claim 1, when the airbag is inflated, the folded portion provided on at least one of the first and second base fabrics expands as a gusset so that the inflation in the inflation direction occurs. The dimensions can be easily set large. In addition, the first and second base fabrics can be sewn with substantially the same planar shape, thereby facilitating the stitching operation and reducing the manufacturing cost. Furthermore, the bulging dimension can be easily increased by providing the folded portion on each base fabric. Further, by arranging the folded portions so that the folding lines cross each other, the overlap of the folded portions in the stitched portion can be reduced or eliminated, and the workability at the time of stitching and the strength of the stitched portion can be easily improved.
[0037]
According to the airbag of the second aspect , in addition to the effect of the first aspect , the folded portion is folded and folded by a pair of substantially parallel folding lines, and the folded portion has a substantially Z-shaped cross section. Thereby, the thickness dimension of an airbag can be made small and the volume at the time of folding this airbag can be made small easily.
[0038]
According to the airbag of the third aspect , in addition to the effect of the first or second aspect , the folded portion is constrained by the pressure of the gas inflow at the time of inflation so as to be ruptured. The lateral expansion can be controlled in multiple stages within a predetermined dimension, and the bulging dimension in the bulging direction can be easily set large.
[Brief description of the drawings]
FIG. 1 is an exploded perspective view showing an embodiment as a premise of an airbag of the present invention.
FIG. 2 is a side view when the airbag is deployed.
FIG. 3 is a perspective view when the airbag is deployed.
FIG. 4 is a sectional view of the airbag.
FIG. 5 is a cross-sectional view showing another embodiment of the airbag of the present invention.
FIG. 6 is an exploded perspective view showing an embodiment of the airbag of the present invention.
FIG. 7 is a cross-sectional view showing still another embodiment of the airbag of the present invention.
FIG. 8 is an exploded perspective view of the airbag.
FIG. 9 is a partial cross-sectional view showing still another embodiment of the airbag of the present invention.
FIG. 10 is a partial cross-sectional view showing still another embodiment of the airbag of the present invention.
FIG. 11 is an explanatory view showing an airbag device.
FIG. 12 is a side view with a part cut away showing a conventional airbag.
FIG. 13 is an explanatory view showing a deployed state of the airbag device.
[Explanation of symbols]
11 Airbag
21 Upper base fabric as second base fabric
22 Lower base fabric as first base fabric
25 Folding part a, b, c, d Folding line

Claims (3)

A bag-like airbag in which gas flows in and inflates and expands in a predetermined inflating direction,
A first base fabric and a second base fabric positioned on the bulging direction side of the first base fabric;
These include a first folded portion provided on the first base fabric, and a second folded portion provided on the second base fabric and having a fold line intersecting with the fold line of the first folded portion. The airbag according to claim 1, wherein the first and second base fabrics are formed by folding each folded portion into a plane shape substantially the same as the other, and stitched into a bag shape. Folded portion is claim 1 Symbol placement airbag, characterized in that folded is folded substantially parallel pair of fold lines. The airbag according to claim 1 or 2 , wherein the folded portion is constrained to be ruptured by a pressure of gas inflow during expansion.

Images