JPH0930353A - Airbag device - Google Patents

Abstract

(57) 【Abstract】 PROBLEM TO BE SOLVED: To control a deployment shape of an airbag bag from an early stage when the airbag starts to deploy. SOLUTION: In the inside of the airbag bag 20, two straps 26 having the same shape are arranged at symmetrical positions on both left and right sides with an inflator 28 interposed therebetween. A front end of each strap 26 is fixed to the inner wall of the occupant-side cloth 22, and a rear end thereof is fixed to the inner wall of the vehicle body-side cloth 24. The vertical width (y-axis direction) W of each strap 26 is larger than the vertical outer diameter dimension L of the gas ejection portion 28A of the inflator 28.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an airbag device attached to a steering wheel or the like of a vehicle.

[0002]

2. Description of the Related Art In recent years, an airbag device has been proposed as a device for protecting an occupant in an emergency of a vehicle. This airbag device allows the gas ejected from the ejection holes of the inflator to flow into the inside of the airbag bag when the vehicle suddenly decelerates, so that the airbag bag is expanded from the folded state to the front of the occupant. It deploys and protects passengers.

As a conventional airbag device, for example, as disclosed in Japanese Patent Laid-Open No. 4-283145, a strap whose length can be changed in two steps is provided inside the airbag bag. There is something. FIG. 13 is a cross-sectional view showing a cross section of a conventional airbag device as viewed from above. As shown in FIG. 13, the air bag body 226.
Inside the inside of the strap is a strap 236 made of a pair of woven fabrics.
Are arranged. One end 23 of the strap 236
6A is folded back along the opening edge portion 227 of the airbag bag 226, is sandwiched between the retainer 232 and the side wall portion 222B of the case 222, and is fixed by the bolt 228 and the nut 230. Also, the strap 236
The other end portion 236B is sewn to the peripheral edge portion 226C of the body cloth 226A of the airbag bag 226 and the side surface cloth 226B. In addition, a folding portion 236C as an extension portion is formed at a substantially central portion of the strap 236. The folding part 236C is configured such that the strap 236 is folded a predetermined number of times and the folding part 23 is folded in the folded state.
The suture thread 237 is sewn to approximately the entire area of 6C with a predetermined strength. Therefore, when a tensile force of a predetermined value or more is applied to the strap 236, the suture thread 237 extends the length of the broken strap 236 from the first length to the second length. A cylindrical inflator 234 is provided on the bottom of the case 222.

Therefore, when the vehicle body is suddenly decelerated, the inflator 23
When gas is generated from No. 4 and flows into the inside of the airbag bag body 226, the airbag bag body 226 starts to deploy. Then, with the expansion of the airbag bag 226, the strap 2
When 36 extends to the first length, the airbag bag 226
The strap 236 is prevented from being deployed in the occupant direction, and is deployed in a direction orthogonal to the occupant direction to form a desired deployed shape. After that, when the internal pressure of the airbag bag 226 rises and the tensile force acting on the strap 236 reaches a predetermined value or more, the suture thread 237 is broken and the strap 236 extends to the second length. As a result, the airbag bag body 226
After the deployment is completed, it can be deployed again toward the occupant side, and the strap 236 having the second length can achieve a desired final deployed shape.

[0005]

However, in the above-mentioned conventional airbag device, the airbag bag body 2 is used.
After 26 starts to deploy, the strap 236 extends,
There is a problem in that the expanded shape of the airbag bag 226 cannot be controlled until it is in a stretched state (that is, the first length).

Therefore, an object of the present invention is to solve the above-mentioned problems of the prior art and to control the deployed shape of the airbag bag from the initial stage when the airbag bag starts to be deployed. To provide a device.

[0007]

In order to achieve the above object, the invention according to claim 1 is an inflator for ejecting gas from a gas ejecting portion when a predetermined impact is applied to a vehicle. An airbag bag body that is expanded from a folded state by causing the gas ejected from the gas ejection part to flow into the inside thereof, wherein the airbag device has a band shape and a rear end thereof is It is fixed near the inflator, and its front end is fixed to a surface of the airbag bag facing the inflator (hereinafter referred to as a facing surface), and when the airbag bag is deployed, the airbag is opposed to the inflator. While limiting the distance to the surface to a predetermined value or less, the width between the upper end and the lower end is wider than the outer diameter dimension in the vertical direction of the gas ejection portion in the inflator, Serial when the air bag body is expanded, are summarized as further comprising a partition member which prevents so as not to flow the gas ejected from the gas ejection portion in the lateral direction.

That is, according to the first aspect of the invention, when gas is ejected from the gas ejecting portion of the inflator and the airbag bag starts to be inflated, at the initial stage of inflating, the partition body causes the partition to eject the gas from the gas ejecting portion. The jetted gas is blocked from flowing in the left-right direction. The gas whose flow is blocked flows partially in the vertical direction and the rest flows in the front-back direction.
In the latter stage of deployment, the partition body is in a tensioned state, so that the distance from the inflator to the facing surface inside the airbag bag is restricted to a predetermined value or less.

The left-right direction means the vehicle width direction, and the up-down direction means the direction parallel to the surface of the steering wheel and the up-down direction viewed from the occupant. A front end indicates a front end in the vehicle traveling direction, a rear end indicates a rear end, an upper end indicates an upper end in the vertical direction, and a lower end indicates a lower end.

According to a second aspect of the present invention, in the airbag apparatus according to the first aspect, the size of the lower end of the partition body from the fixing point near the inflator to the fixing point on the facing surface is The gist is that it is shorter than the dimension of the upper end.

That is, in the invention described in claim 2, since the dimension of the lower end of the partition is shorter than the dimension of the upper end, when the partition is stretched in the latter stage of the expansion, from the inflator to the lower part of the facing surface. Is regulated to be shorter than the distance to the top. As a result, when the airbag bag is viewed from the side, the lower portion of the airbag bag has a V shape.

According to a third aspect of the present invention, in the airbag apparatus according to the first aspect, the two partition bodies are provided, and the partition bodies are arranged non-parallel to each other with the inflator interposed therebetween. Is the gist.

That is, in the invention described in claim 3, 2
Since the partitions are arranged non-parallel with the inflator in between, the gas whose flow is blocked by the partitions is
For example, in the case of flowing in the up-down direction, the flowing amount differs between upward and downward. As a result, the upward deployment speed and the downward deployment speed of the airbag bag body are different.

[0014]

Other Embodiments of the Invention The present invention can also adopt the following other embodiments. According to a first aspect, in the airbag device according to claim 1, the partition body includes a ventilation hole for flowing a part of the gas ejected from the gas ejection portion in the left-right direction. And

In the first aspect, a part of the gas ejected from the gas ejecting portion flows toward both the left and right outer sides of the partition body through the ventilation hole during the expansion of the air bag body.
The deploying speed of the airbag bag in the left-right direction can be increased to a desired speed.

[0016]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below based on Examples. FIG. 1 is a partially cutaway perspective view of a main part of an airbag device as a first embodiment of the present invention. FIG. 1 shows a state in which the airbag bag body 20 is in the final deployed state.
Only the upper half of 0 is drawn. FIG. 2 is a perspective view showing the airbag device of FIG. 1 cut along the line II-II ′. In FIG. 2, only the right half of the airbag 20 is drawn.

FIG. 3 shows the airbag device II- of FIG.
It is a sectional view showing a section along the II 'direction. Note that FIG.
Then, the shape of the airbag body 20 and the strap 26 looks a little different from the shape shown in FIG. 1 or 2, but the steering wheel pad 34 or the like is omitted in FIG. 1 or 2. It is because it is drawn.

The airbag apparatus of this embodiment is an airbag apparatus for a driver's seat, and as shown in FIG. 1, FIG. 2 or FIG. 3, is mainly composed of an airbag bag 20 and an inflator 28. There is. The airbag 20 is formed by joining the dome-shaped cloth 22 and the vehicle-side cloth 24, each of which has a dome shape, with their openings facing each other and joining the peripheral edges of the openings. An inflator hole is provided in the center of the vehicle body side cloth 24, and the airbag bag body 20 is opened from the hole.
The inflator 28 is inserted toward the inside.
The vehicle body side cloth 24 is fixed to the inflator 28 at the peripheral portion of the inflator hole.

The inflator 28 has a cylindrical shape,
A gas ejection portion 28A having a plurality of ejection holes for ejecting gas is provided on the outer periphery. Inside the inflator 28, a gas generating substance (not shown) is filled and an ignition means (not shown) is provided. The inflator 28 is arranged inside the steering wheel pad 34, and is joined to the base plate 36 at the collar portion 28B. The base plate 36 is fixed to the steering wheel pad 34 by being screwed with bolts and nuts. Further, the vehicle side cloth 24 is provided with vent holes 30 at positions symmetrical with respect to the inflator hole.

Inside the airbag bag 20, two straps 26 having the same shape are arranged at symmetrical positions on both the left and right sides with the inflator 28 interposed therebetween. A front end of each strap 26 is fixed to the inner wall of the occupant-side cloth 22, and a rear end thereof is fixed to the inner wall of the vehicle body-side cloth 24. The length H between the front end and the rear end is set to a desired dimension.

Vertical direction of each strap 26 (y-axis direction)
The width W is larger than the outer diameter dimension L of the gas ejection portion 28A in the inflator 28 in the vertical direction, and further wider than the inner diameter dimension M of the steering wheel pad 34 in the vertical direction (y-axis direction). In addition, the airbag bag body 20
Compared with the inner diameter in the vertical direction (y-axis direction) of,
The width W of each strap 26 in the vertical direction (y-axis direction) is about 1/3 or more and 1/2 or less of the inner diameter dimension of the airbag 20.

The interval between the straps 26 is set in the left-right direction (x-axis direction) of the steering wheel pad 34.
It is shorter than the inner diameter of. In addition, strap 2
The rear end of 6 is fixed to the inner wall of the vehicle body side cloth 24 as described above, but since the fixed portion is actually collected in the steering wheel pad 34 as shown in FIG. 3, The rear end portion of the strap 26 is wrinkled.

The occupant side cloth 22, the vehicle body side cloth 24 and the strap 26 are fixed to each other by stitching, bonding or the like. In addition, the strap 26 may be coated with silicon in order to improve heat resistance.

The airbag device shown in FIG. 1 is normally stored in the space between the pad cover 34A in the steering wheel pad 34 and the inflator 28 with the airbag bag 20 folded. Has been done.

Therefore, when the value based on the deceleration applied to the vehicle body exceeds a predetermined value, the ignition means in the inflator 28 is activated to ignite the gas generating substance, and gas is ejected from the gas ejection portion 28A of the inflator 28. . When the ejected gas flows into the inside of the airbag bag 20, the airbag bag 20 swells, cuts the pad cover 34A of the steering wheel pad 34 as shown in FIG. 3, and expands in front of the occupant.

FIG. 4 is a front view showing a state of the airbag bag 20 of FIG. 1 in an initial stage of deployment, and FIG. 5 is a front view showing a state of the latter stage of the same stage of deployment. As shown by the arrow in FIG.
The air bag body 2 in the steering pad 34 is generated by the gas ejected from the gas ejecting portion 28A of the inflator 28.
The internal pressure of 0 rises, the force causes the pad cover 34A to rupture, and the airbag bag 20 is deployed. After that, the gas ejected from the gas ejection portion 28A spreads in all directions. However, since the straps 26 are disposed on both the left and right sides of the inflator 28, the gas ejected in the left-right direction (x-axis direction) from the gas ejecting portion 28A is trapped by the strap 26.
Blocks the flow. As a result, the ejected gas flows along the strap 26 in the vertical direction (y-axis direction) and also in the front-back direction (z-axis direction) in the forward direction (toward the occupant). The airbag 20 has a vertically elongated shape as a whole as shown in FIG. 4, because the deployment speed is increased in the vertical direction by the gas flowing in the vertical direction (y-axis direction).

FIG. 6 is an explanatory view for explaining the positional relationship between the airbag bag 20 and the occupant when the airbag bag 20 of FIG. 1 is deployed. As shown in FIG. 6, compared with the other seats in the vehicle, the steering wheel 32 is arranged in front of the seat 39 in the driver's seat, so that the space extending in front of the abdomen of the occupant 38 is narrow. However, in this embodiment,
As described above, since the airbag bag body 20 has a vertically long shape in the initial stage of deployment, it can be easily deployed in the space in front of the abdomen of the occupant 38. It should be noted that the portion of the airbag bag 20 that has once expanded into the space will not escape from the space because gas is constantly ejected from the inflator 28 and supplied thereafter.

Subsequently, the gas flowing in the vertical direction (y-axis direction) along the strap 26 is finally blocked by the inner wall of the airbag bag body 20, so that the gas wraps around toward both the left and right outer sides of the strap 26. start. Then, as shown in FIG. 5, the air bag body 2 is circulated by the circulated gas.
0 starts to develop in the horizontal direction (x-axis direction) this time. Further, at this time, since the forward flow in the front-rear direction (z-axis direction) (the direction toward the occupant 38) also continues, the deployment amount of the airbag 20 in the front-rear direction (that is, the direction toward the occupant 38). The amount of popping out) also increases. However, as described above, the length H of the strap 26 is
Is set to a desired size, so that when the strap 26 extends and is in a stretched state, the airbag bag body 20 is prevented from expanding in the front-rear direction, and the pop-out amount is regulated to a desired value. Thus, in the latter stage of deployment, the amount by which the airbag bag 20 pops out can be regulated by the strap 26 to a desired value.

Since the vehicle body side cloth 24 is provided with the vent hole 30 as described above, during deployment, a part of the gas flowing in the airbag bag body 20 is released through the vent hole 30 to the outside. Is released to. Thereby, the internal pressure in the airbag bag 20 is adjusted to an appropriate value.

As described above, according to this embodiment, the strap 26 blocks the flow of the gas ejected in the left-right direction (x-axis direction) even before the strap 26 is in a tensioned state, and Since the flow can be changed in the direction (y-axis direction), the shape of the airbag bag 20 can be controlled to be a vertically long shape at the initial stage of deployment.

Further, the strap 26 used to regulate the amount of the air bag body 20 that pops out is provided with a function of changing the flow of the ejected gas as described above, so that a new function for fulfilling such a function is provided. Since it is not necessary to provide an additional member, the airbag bag 20 can be manufactured as it is, and the cost increase can be suppressed.

FIG. 7 is a perspective view showing a main part of an airbag apparatus as a second embodiment of the present invention, with a part thereof cut away. In FIG. 7, only the right half of the airbag 40 is drawn. In the present embodiment, as shown in FIG. 7, in the strap 46 provided in the airbag body 40, the dimension of the lower end (the length of the lower end in the z-axis direction) H2 is the dimension of the upper end (the z of the upper end).
It is shorter than the axial length) H1. For this reason,
In the latter stage of the deployment, the strap 46 becomes taut and the amount of deployment of the airbag 40 in the front-rear direction (that is,
When the amount of protrusion in the direction toward the occupant 38) is regulated, the strap 46 is regulated so that the amount of protrusion of the lower portion of the airbag bag 40 is smaller than the amount of protrusion of the upper portion.

FIG. 8 is an explanatory view for explaining the positional relationship between the airbag bag body 40 and the occupant when the airbag bag body 40 of FIG. 7 is deployed. As shown in FIG. 8, the space sandwiched between the occupant 38 and the steering wheel 32 has a V-shape when viewed from the side. On the other hand, the airbag bag 40 in the present embodiment is regulated by the strap 46 so that the protruding amount of the lower portion is smaller than the protruding amount of the upper portion as described above, and therefore the shape of the airbag bag member 40 viewed from the side. Has a V shape like the above space.

Therefore, even if an impact is applied to the vehicle in the front-rear direction and the upper body of the occupant 38 moves forward to the position indicated by 38a, as shown in FIG.
Since the shape of 0 is V-shaped as described above, the airbag 40 can be easily deployed in front of the abdomen of the occupant 38.

FIG. 9 is a perspective view showing a partially broken main portion of an airbag device according to a third embodiment of the present invention. In FIG. 9, only the right half of the airbag 50 is drawn. The difference between the present embodiment and the first embodiment is clear from a comparison between FIG. 9 and FIG.
In the figure, the position where the front end of the strap 56 is fixed to the occupant-side cloth 22 is located above (in the y-axis direction) the case of the first embodiment.

FIG. 10 is an explanatory view for explaining the positional relationship between the airbag bag body 50 and the occupant when the airbag bag body 50 of FIG. 9 is deployed. In this embodiment, as shown in FIG. 10, when the airbag bag 50 is deployed, the strap 56 itself tends to extend along the z-axis direction, so that the front end of the strap 56 is fixed at the upper position. As a result, the airbag bag 50 has a greater amount of expansion in the lower portion than in the upper portion (that is, the lower portion is more inflated). In this way, the expansion amount of the lower portion of the airbag bag 50 is increased, so that the effect of protecting the abdomen of the occupant 38 is further enhanced.

FIG. 11 is a front view showing the airbag bag body in the airbag apparatus as the fourth embodiment of the present invention from the front. In this embodiment, as shown in FIG. 11, the two left and right straps 66 provided in the airbag bag 60 are arranged so as not to be parallel to each other, and at this time, the lower ends of the straps 66 are The distance between them is wider than the distance between the upper ends.

By arranging the left and right straps 66 in this manner, the amount of gas flowing downward in the vertical direction (y-axis direction) is larger than the amount of gas flowing upward, so that the airbag bag body In the unfolding of 60, the downward unfolding speed is faster than the upward unfolding speed. As a result, the air bag body 60 expands and bulges downward in the vertical direction (y-axis direction) more quickly.

FIG. 12 is a perspective view showing a main part of an airbag device partially broken away as a fifth embodiment of the present invention. In FIG. 12, only the right half of the airbag 70 is drawn. In this embodiment, as shown in FIG. 12, the strap 76 provided in the airbag bag body 70 has a vent hole 78 in the central portion. Therefore, the airbag bag 7
During the deployment of 0, a part of the gas ejected from the inflator 28 will flow toward both the left and right outer sides of the strap 76 through the ventilation holes 78. As a result, the pressure in the space sandwiched by the left and right straps 76 can be reduced, and the deployment speed of the airbag 70 in the left-right direction (x-axis direction) can be increased. In addition,
The size, shape, or number of the ventilation holes 78 is arbitrary, and the pressure in the space and the expansion speed are adjusted to desired values by setting the sizes, shapes, and numbers of the ventilation holes 78 to appropriate values. be able to.

In each of the above embodiments, the strap has a rectangular shape or a similar shape, but the present invention is not limited to this, and at least a strap may be formed. . Therefore, for example, the entire shape may be a parallelogram shape, a trapezoidal shape, or another polygonal shape, or an oval or part of an ellipse. Further, the edges of the upper and lower edges of the strap may have a wavy line or a polygonal line shape instead of the straight line shape.

Further, in each of the above embodiments, the rear end of the strap is fixed to the inner wall of the vehicle body side cloth 24, but it may be fixed to the fixing portion between the inflator 28 and the vehicle side cloth 24. good. Further, the strap may be provided with folds or irregularities for controlling the gas flow.

[0042]

As described above, according to the first aspect of the present invention, the partition body extends in the left and right direction of the ejected gas even before the partition body extends and is in a stretched state. Since the flow can be blocked and the gas flow can be changed, the deployment shape of the airbag bag can be controlled from the initial stage when the airbag bag starts to deploy. Also, the partition body regulates the amount of protrusion of the airbag bag body,
Since it also has the function of changing the flow of gas as described above, it is not necessary to provide a new additional member to fulfill such a function, and the airbag bag can be manufactured as it is at the current time, which increases the cost. Can be suppressed.

According to the second aspect of the invention, the distance from the inflator to the lower part of the facing surface is regulated to be shorter than the distance to the upper part, and when the airbag bag is viewed from the side, the airbag bag is viewed. Since the lower part of the body is V-shaped,
The airbag bag can be easily deployed in front of the abdomen of the occupant.

In the invention described in claim 3, for example, the amount of gas flowing upward and the amount of gas flowing downward are changed,
Since the downward expansion speed can be made faster than the upward expansion speed of the airbag bag, the effect of protecting the abdomen of the occupant can be increased.

[Brief description of drawings]

FIG. 1 is a partially cutaway perspective view of a main part of an airbag device according to a first embodiment of the present invention.

FIG. 2 is a perspective view showing the airbag device of FIG. 1 cut along a II-II ′ direction.

FIG. 3 is a cross-sectional view showing a cross section along the II-II ′ direction of the airbag device of FIG.

FIG. 4 is a front view showing an initial state of deployment of the airbag bag body 20 of FIG.

FIG. 5 is a front view showing a state of the airbag bag body 20 of FIG. 1 in the latter half of the deployment.

FIG. 6 is an explanatory diagram for explaining a positional relationship between the airbag bag body 20 and an occupant when the airbag bag body 20 of FIG. 1 is deployed.

FIG. 7 is a perspective view showing a main part of an airbag device as a second embodiment of the present invention with a part thereof cut away.

8 is an explanatory diagram for explaining a positional relationship between the airbag bag body 40 and an occupant when the airbag bag body 40 of FIG. 7 is deployed.

FIG. 9 is a perspective view showing a partially broken main part of an airbag device as a third embodiment of the present invention.

10 is an explanatory diagram for explaining a positional relationship between the airbag bag body 50 and an occupant when the airbag bag body 50 of FIG. 8 is deployed.

FIG. 11 is a front view showing the airbag bag body in the airbag apparatus as the fourth embodiment of the present invention from the front.

FIG. 12 is a perspective view showing a partially broken main part of an airbag device according to a fifth embodiment of the present invention.

FIG. 13 is a cross-sectional view showing a cross section of a conventional airbag device as viewed from above.

[Explanation of symbols]

 20 ... Air bag body 22 ... Occupant side cloth 24 ... Car body side cloth 26 ... Strap 28 ... Inflator 28A ... Gas ejection part 28B ... Collar part 30 ... Vent hole 32 ... Steering wheel 34 ... Steering wheel pad 34A ... Pad cover 36 ... Base plate 38 ... Occupant 39 ... Seat 40 ... Airbag bag 46 ... Strap 50 ... Airbag bag 56 ... Strap 60 ... Airbag bag 66 ... Strap 70 ... Airbag bag 76 ... Strap 78 ... Vent 222 ... Case 222B ... Side wall part 226 ... Air bag body 226A ... Main body cloth 226B ... Side cloth 226C ... Perimeter part 227 ... Opening edge part 228 ... Bolt 230 ... Nut 232 ... Retainer 234 ... Inflator 236 ... Strap 236A ... End part 236B ... End part 236C ... Folding part 237 ... suture

Claims (3)

[Claims] 1. An inflator that ejects gas from a gas ejecting portion when a predetermined impact is applied to a vehicle, and an inflator that is inflated from the folded state by causing the gas ejected from the gas ejecting portion to flow inside. An airbag device including: an airbag device, which has a belt-like shape, a rear end of which is fixed near the inflator, and a front end of which faces the inflator in the airbag bag (hereinafter, When the airbag is deployed, the distance from the inflator to the facing surface is restricted to a predetermined value or less, and the width between the upper end and the lower end is fixed to the inflator. The outer diameter of the gas ejection portion in the vertical direction is larger than the outer diameter dimension of the gas ejection portion, and the gas ejected from the gas ejection portion in the lateral direction when the airbag bag is deployed. An airbag device that has a partition that prevents it from flowing to the inside. 2. The airbag device according to claim 1, wherein the partition body is such that a dimension of the lower end from a fixing point near the inflator to a fixing point on the facing surface is shorter than a dimension of the upper end. Bag device. 3. The airbag device according to claim 1, further comprising two partition bodies, each partition body being arranged non-parallel to each other with the inflator interposed therebetween.