JPH1095294A - Air bag device for vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To start restraining of an occupant in an early stage in an air bag device with an inflator and an air bag disposed at the central part of a steering wheel disposed almost horizontally. SOLUTION: An air bag 10 is formed of lower cloth 12 fitted to the inflator side, upper cloth 14 relative to the lower cloth 12, and side face cloth 16 connecting both cloth 12, 14. In bag shape at the time of completing expansion, the part, relative to an occupant P, of the side face cloth 16 becomes almost vertical so as to form a nearly vertical wall in front of the occupant P by the air bag 10. When the occupant P moves forward at the time of a vehicle collision, the air bag 10 therefore stops the chest and head of the occupant P in an early stage to start restraining the occupant P.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an airbag device for a vehicle, and more particularly to an airbag device used for a driver's seat in a vehicle having an upward steering wheel such as a truck, a bus and a van.

[0002]

2. Description of the Related Art An airbag used in an airbag device for a driver's seat generally includes:
Two circular cloths, an inflator-side cloth and an occupant-side cloth,
The outer peripheral edges are sewn together to form a bag, and in a folded state, are housed together with the inflator in the center of the steering wheel and are inflated by the gas generated by the inflator.

In trucks, buses, vans, and the like, the steering wheel is disposed such that its wheel plane is at an angle of 45 ° or less with respect to a horizontal plane, and is generally substantially horizontal as shown in FIG. It is arranged in.

When the above-described conventional airbag device is provided on such a substantially horizontally arranged steering wheel 2, the occupant must be restrained early because the shape of the airbag when the inflation is completed is flat. Is difficult.

That is, as shown in FIG. 10, the airbag 100 is disposed together with the inflator 104 on a boss 2a at the center of the steering wheel 2 disposed substantially horizontally. However, in the case of the above-described conventional airbag 100, the circular inflator-side cloth 101 and the occupant-side cloth 1
02 is sewn 103, so that the bag shape when the inflation is completed becomes flat. In the flatly deployed airbag 100, it is difficult to quickly restrain an occupant who falls forward in the event of a vehicle collision, when the airbag 100 is used for the steering wheel 2 arranged substantially horizontally.

Accordingly, the present invention provides an airbag device disposed on a steering wheel having a wheel plane disposed at an angle of 45 ° or less with respect to a horizontal plane, which can restrain an occupant early. The purpose is to provide.

[0007]

According to a first aspect of the present invention, there is provided an airbag apparatus for a vehicle, wherein a wheel plane is 4 degrees with respect to a horizontal plane.
An airbag device comprising an inflator and an airbag inflated by the inflator at a central portion of a steering wheel arranged at an angle of 5 ° or less, wherein the airbag is mounted on an inflator side. And an upper cloth opposed to the lower cloth, and a side cloth connecting the upper cloth and the lower cloth. In a bag shape at the time of completion of inflation, a portion of the side cloth facing the occupant is substantially vertical. It is characterized by the following.

In the above configuration, the side cloth connecting the upper cloth and the lower cloth is substantially vertical at a portion facing the occupant when the inflation of the airbag is completed. That is, the inflated airbag forms a substantially vertical wall in front of the occupant. Therefore, when the occupant moves forward during a vehicle collision, the airbag catches the occupant's chest and head early. That is, it is possible to start restraining the occupant early.

According to a second aspect of the present invention, in the airbag device for a vehicle according to the first aspect, the side cloth is formed by joining two upper and lower cloths having a hole at a central portion at peripheral edges of the hole. An outer edge of the upper cloth of the side cloth is joined to an outer edge of the upper cloth, and an outer edge of the lower cloth is joined to an outer edge of the lower cloth, thereby forming the airbag. .

As described above, by arranging the side cloth with two upper and lower cloths, the airbag can be easily folded, and as a result, the package volume of the folded airbag can be reduced.

According to a third aspect of the present invention, there is provided the airbag device for a vehicle according to the second aspect, wherein each of the joints between the upper and lower cloths of the side cloth, the upper cloth and the lower cloth is circular. And

If the joining portion is made circular as described above,
When the joint is formed by sewing, the sewing is easy, and the airbag can be manufactured using the existing sewing equipment as it is.

According to a fourth aspect of the present invention, there is provided the vehicle airbag device according to the second or third aspect, wherein, at a joint portion between the upper and lower cloths of the side cloth, both edges at opposing positions in the joint portion are connected to each other. It is characterized by being connected by a tether that regulates the interval so as not to spread beyond a predetermined length.

As described above, by connecting the opposite edges of the joint provided on the peripheral edge of the hole of the side cloth with the tether, the tension acting on the joint when the airbag is inflated can be reduced. Thus, the pressure resistance of the bag can be improved.

According to a fifth aspect of the present invention, there is provided an airbag device for a vehicle according to any one of the second to fourth aspects, wherein
The joint portion of the pieces of cloth and the inflator mounting portion of the lower cloth are connected to each other by a tether that regulates a gap between the two pieces so as not to be longer than a predetermined length.

As described above, by connecting the joint provided on the peripheral edge of the hole of the side cloth to the inflator mounting portion of the lower cloth with the tether, rebound during the deployment of the airbag is reduced, and a good deployed shape is achieved. Can be secured.

[0017]

Embodiments of the present invention will be described below with reference to the drawings.

First, an airbag device according to a first embodiment will be described.

FIG. 1 is a side view showing a state of the airbag device according to the first embodiment of the present invention when the inflation of the airbag is completed, and FIG. 2 is a longitudinal sectional view thereof.

In this airbag device, the airbag 10 is stored in a folded state together with the inflator 24 in a boss 2a at the center of the steering wheel 2 which is disposed substantially horizontally.

The steering wheel 2 provided with the airbag device is attached to the tip of a rotatable wheel shaft 3 and has an inclination with respect to a horizontal plane, that is, an angle α formed between the plane of the steering wheel 2 and the horizontal plane.
Is set to 45 ° or less. This angle α is 30
° or less.

The airbag 10 is formed of a lower cloth 12 attached to the inflator 24, an upper cloth 14 facing the lower cloth 12, and a side cloth 16 connecting these cloths 12, 14.

The lower cloth 12 is formed in a circular shape, and has a circular mounting hole 26 formed at the center thereof to which a gas outlet of the inflator 24 is mounted. Reference numeral 28 denotes a reinforcing cloth for reinforcing the mounting opening 26.

The upper cloth 14 is formed in a circular shape smaller in diameter than the lower cloth 12.

The side cloth 16 has a substantially cylindrical shape having upper and lower openings formed by stitching both ends of a single substantially band-shaped cloth 22, and the upper opening edge is smaller in diameter than the lower opening edge. . Then, as shown in FIG. 2, the lower opening edge is sewn 18 to the outer peripheral edge of the lower cloth 12, and the upper opening edge is sewn 20 to the outer peripheral edge of the upper cloth 14, whereby when the bag inflation is completed, 1, an airbag 10 having a substantially truncated cone shape with the rotation axis of the wheel shaft 3 as a central axis is configured. The height h of the airbag 10 from the plane of the steering wheel 2 at the time of completion of the bag inflation is set to be 60 to 120% with respect to the diameter Ds of the steering wheel 2, so that the restraint of the occupant P can be suppressed early. It is preferable for starting.

As shown in FIG. 1, when the inflation of the airbag 10 is completed, the portion of the side cloth 16 facing the occupant P is configured to be substantially perpendicular to the horizontal plane. That is, the angle β between the straight line connecting the upper and lower ends of the portion of the side cloth 16 facing the occupant P and the horizontal plane is 60 degrees.
° to 120 °. This angle β is 75 °
It is preferable that the angle is about 105 ° in order to receive the occupant P well.

In the airbag device of this embodiment, the airbag 10 disposed in a folded state in the boss portion 2a of the steering wheel 2 is caused by gas generated by the inflator 24 at the time of a vehicle collision as shown in FIG. In the shape at the time of completion of the expansion, the portion of the side cloth 16 facing the occupant P becomes substantially vertical. That is, a substantially vertical wall is formed by the airbag 10 in front of the occupant P. for that reason,
When the occupant P tries to fall forward due to the collision of the vehicle, the airbag 10 receives the chest or head of the occupant P early, whereby the restraint of the occupant P is started early.

The airbag 10 is disposed on the boss 2a of the steering wheel 2 and inflates therefrom into a substantially truncated cone with the rotation axis of the wheel 2 as a center axis. Even in the case of rotation, a substantially vertical wall is formed by the airbag 10 in front of the occupant P. Therefore, the restraint of the occupant P is started early regardless of the rotation angle of the steering wheel 2.

Next, an airbag device according to a second embodiment will be described.

FIG. 3 is a side view showing a state of the airbag apparatus according to the second embodiment of the present invention when the inflation of the airbag is completed, and FIG. 4 is a longitudinal sectional view thereof.

In the airbag device of this embodiment, the structure of the side cloth of the airbag is different from that of the first embodiment.

That is, in the airbag 30 of the present embodiment, the side cloth 16 is composed of two upper and lower cloths 34 and 32.

As shown in FIG. 6, the air bag 30 includes a central without the lower cloth 12 having a mounting hole 26 for the inflator mounted on the central portion a circular shape with a diameter D _0, also a circular shape having a diameter D ₀ a first side fabric 32 having a circular hole 38 of diameter D ₁ in section, a second side fabric having a circular hole 38 of diameter D ₁ in the central portion a circular shape of small consisting diameter D ₂ than D ₀ 3
4, is formed by four fabric upper cloth 14 forming a circular shape with a diameter D _2.

Then, the side cloth 16 is integrally formed by stitching the first side cloth 32 and the second side cloth 34 together at the outer peripheral edges of the holes 38 thereof, and the outer side of the first side cloth 32 is formed. The peripheral edge is stitched 18 to the outer peripheral edge of the lower cloth 12, and the outer peripheral edge of the second side cloth 34 is stitched 20 to the outer peripheral edge of the upper cloth 14 to form the airbag 30.

The airbag 30 has a shape in which, when the inflation of the bag is completed, two upper and lower circular bags stacked around the rotation axis of the wheel shaft 3 are stacked. As shown in FIG. 4, the side cloths 16 communicate with each other through holes 38. Then, the upper cloth 14 and the second side cloth 3
4 is formed smaller than the lower bag formed by the lower cloth 12 and the first side cloth 32. The height h of the airbag 30 from the plane of the steering wheel 2 at the time of completion of bag inflation is also:
As in the first embodiment, it is preferable that the diameter is set to 60 to 120% of the diameter Ds of the steering wheel 2.

As shown in FIGS. 4 and 5, a stitching portion 36 of the side cloth 16 between the first side cloth 32 and the second side cloth 34 has
Both edges of opposing positions in the suturing portion 36 are connected by a first tether 40 that regulates the interval between them so as not to extend beyond a predetermined length. That is, the first tether 40 connects the holes 38 of the side cloth 16 in the radial direction, and restricts the holes 38 from expanding beyond a predetermined length when the airbag 30 is inflated.

It is to be noted that the first tether 40 is
6, one or both of the holes 38 of the first side cloth 32 and the second side cloth 34 may be formed by cutting in advance into a shape having a tether 40 as shown in FIG. Further, a different cloth from the first and second side cloths 32 and 34 is cut into a shape shown in FIG.
The first tether 4 is sewn 36 together with the side cloths 32 and 34.
A side cloth 16 having zero may be formed.

The lower cloth 12 and the upper cloth 14 are connected to each other by a pair of second tethers 42 for restricting the space between the cloths 12 and 14 from expanding beyond a predetermined length when the bag is inflated. The pair of second tethers 42, 42 are attached to symmetrical positions around the mounting opening 26 of the lower cloth 12, and are attached to the upper cloth 14 through the holes 38 of the side cloth 16. FIG.
As shown in the figure, the first tether 40 is inserted between the pair of second tethers 42 in the hole 38 of the side cloth 16.
Is arranged.

As shown in FIG.
Also, similarly to the airbag 10 in the first embodiment, when the inflation of the bag is completed, the portion of the side cloth 16 facing the occupant P is substantially perpendicular to the horizontal plane. That is, the angle β between the straight line connecting the upper and lower ends of the portion of the side cloth 16 facing the occupant P and the horizontal plane is set to 60 ° to 120 °. In addition, it is preferable that this angle β is 75 ° to 105 ° in order to properly receive the occupant P.

Therefore, even in this airbag device, a substantially vertical wall is formed by the airbag 30 in front of the occupant P in the event of a vehicle collision. The chest or head of the occupant P is received, so that the restraint of the occupant P is started early.

The airbag 30 is also inflated into a two-stage circular bag having the rotation axis of the steering wheel 2 as a center axis, so that the airbag 30 is in front of the occupant P regardless of the rotation angle of the steering wheel 2. A substantially vertical wall is formed by 30 so that the restraint of the occupant P can be started early.

In particular, in the case of the airbag 30, the side cloth 16 is formed by stitching two upper and lower cloths 34 and 32 having a hole 38 in the center at the periphery of the hole 38. The outer peripheral edge of the upper cloth 34 of the side cloth 16 is sewn to the outer peripheral edge of the upper cloth 14 and the outer peripheral edge of the lower cloth 32 to the outer peripheral edge of the lower cloth 12, respectively. Since the airbag 30 is formed, the sewn portions 36, 20, and 18 serve as folds when the airbag 30 is folded, so that the airbag 30 can be easily folded. As a result, the package volume of the folded airbag 30 can be reduced.

Since the sewn portions 36, 20, and 18 are circular, sewing is easy, and the airbag 30 can be manufactured using existing sewing equipment as it is.

Further, the upper and lower two cloths 34 of the side cloth 16,
Since the opposite edges of the 32 stitched portions 36 are connected by the first tether 40, the tension acting on the stitched portions 36 can be reduced when the bag is inflated, and the pressure resistance of the airbag 30 can be reduced. Can be improved.

When the bag is completely inflated, the side cloth 1
As a bag shape in which the portion facing the occupant P of the sixth occupant P becomes substantially vertical, as long as it forms a substantially vertical wall capable of receiving the occupant P substantially, as in the first embodiment, In the case where the portion opposite to has a substantially flat surface, the portion may have a concave portion as in the second embodiment.

FIG. 8 is a longitudinal sectional view of the airbag device according to the third embodiment when the inflation of the airbag is completed.

In the airbag apparatus of this embodiment, the stitching portion 36 of the first side cloth 32 and the second side cloth 34 and the lower cloth 1 in the airbag apparatus of the second embodiment described above.
The second inflator 24 is characterized in that it is connected to the portion of the attachment opening 26 of the inflator 24 by third tethers 44, 44. The third tethers 44, 44 are formed by stitching a pair of band portions of the cloth sewn to the peripheral edge of the mounting opening 26 of the lower cloth 12 at positions facing the holes 38 of the side cloth 16. The gap between the sewn portion 36 and the peripheral edge of the attachment opening 26 of the lower cloth 12 is restricted so as not to be longer than a predetermined length. As described above, the sewn portion 3 provided at the peripheral portion of the hole 38 of the side cloth 16
By connecting the airbag 30 and the inflator 24 mounting portion of the lower cloth 12 with a pair of third tethers 44, rebound during deployment of the airbag 30 can be reduced, and a favorable deployed shape can be secured.

Note that the third tether 44 is
May be used together with the tether 40 or the second tether 42 of FIG.

[0049]

According to the airbag device for a vehicle according to the first aspect of the present invention, in an airbag device disposed on a steering wheel having a wheel plane formed at an angle of 45 ° or less with respect to a horizontal plane, the vehicle can be used at the time of vehicle collision. Since a substantially vertical wall formed by the airbag is formed in front of the occupant, the chest and head of the occupant falling forward can be received early, and the occupant can be restrained early.

According to the airbag device of the second aspect, the airbag can be easily folded and the package volume of the folded airbag can be reduced.

According to the airbag device of the third aspect, the manufacture of the airbag is further facilitated.

According to the airbag device of the fourth aspect, the tension acting on the joint of the side cloth when the airbag is inflated can be reduced, and the pressure resistance of the airbag can be improved.

According to the airbag device of the fifth aspect, the rebound of the airbag in the vertical direction during deployment can be reduced, and a better deployment operation and deployment shape can be ensured.

[Brief description of the drawings]

FIG. 1 is a side view showing a state of an airbag device according to a first embodiment of the present invention at the time of completion of bag inflation.

FIG. 2 is a longitudinal sectional view of the airbag device.

FIG. 3 is a side view showing a state of the airbag device according to a second embodiment of the present invention at the time of completion of bag inflation.

FIG. 4 is a longitudinal sectional view of the airbag device.

FIG. 5 is a perspective view of the airbag device when the inflation of the airbag is completed.

FIG. 6 is a plan view of four cloths constituting the airbag.

FIG. 7 is a plan view showing a modified example of the first side cloth 32 or the second side cloth 34.

FIG. 8 is a longitudinal sectional view of the airbag device according to the third embodiment of the present invention at the time of completion of bag inflation.

FIG. 9 is a schematic side view showing an arrangement state of a steering wheel in a truck.

FIG. 10 is a side view showing a state when the inflation of the conventional airbag device is completed.

[Explanation of symbols]

 Reference Signs List 2 steering wheel 10, 30 airbag 12 lower cloth 14 upper cloth 16 side cloth 18, 20, 36 stitching portion 24 inflator 32 first side cloth 34 second side cloth 38 hole 40 first tether 44 third tether

Claims (5)

[Claims] 1. An airbag device comprising: an inflator; and an airbag inflated by the inflator, at a central portion of a steering wheel having a wheel plane disposed at an angle of 45 ° or less with respect to a horizontal plane. The airbag is formed by a lower cloth attached to the inflator side, an upper cloth opposed to the lower cloth, and a side cloth connecting the upper cloth and the lower cloth. An airbag device for a vehicle, wherein a portion of a cloth facing an occupant is substantially vertical. 2. The side cloth is formed by joining two upper and lower cloths having a hole in the center at the peripheral edges of the holes, and the outer edge of the upper cloth of the side cloth is formed of the upper cloth. On the outer edge,
The vehicle airbag device according to claim 1, wherein an outer edge of the lower cloth is joined to an outer edge of the lower cloth, respectively, to form the airbag. 3. The airbag device for a vehicle according to claim 2, wherein each joint between the upper and lower cloths of the side cloth, the upper cloth and the lower cloth is circular. 4. At a joint portion between two upper and lower cloths of the side cloth, both edges at opposing positions in the joint portion are connected by a tether that regulates a distance between the two members so as not to exceed a predetermined length. The vehicle airbag device according to claim 2 or 3, wherein: 5. A joint portion between the upper and lower two cloths of the side cloth and an inflator mounting portion of the lower cloth are connected by a tether for regulating a distance between the two cloths so as not to exceed a predetermined length. The vehicle airbag device according to any one of claims 2 to 4, wherein: