JP6801385B2 - Driver's airbag and driver's airbag device - Google Patents

Description

The present invention relates to an airbag and an airbag device for restraining an occupant in the event of a collision of an automobile, and more particularly to an airbag and an airbag device for the driver's seat.

The driver airbag device provided on the steering wheel activates an inflator (gas generator) to eject gas in an emergency such as a vehicle collision, supplies gas to the airbag, and drives this airbag with the steering wheel. It is configured to be deployed with the seat occupants.

As a driver's seat airbag, one in which the peripheral edges of the front panel and the rear panel are sewn together is known.

Patent Document 1 describes an airbag for a driver's seat provided with a notch having a shape that cuts into a substantially V shape from the peripheral edge of the rear panel toward the center of the rear panel. In the expanded state of the driver's seat airbag of Patent Document 1, the distance from the sewn portion between the front panel and the rear panel to the front surface (maximum occupant surface) of the front panel is compared with the distance from the sewn portion to the rear end of the rear panel (central portion of the front panel). ) Is large. Notches are provided at two locations in the circumferential direction of the rear panel.

Patent Document 2 describes a driver's seat airbag having a conical rear portion, which is manufactured by providing a V-shaped notch in a rear panel and suturing the rear panel.

Patent Document 3 describes that a tack (referred to as "wrinkle" in Patent Document 1) extending in the radial direction is formed by pinching and sewing the peripheral edge portion of the rear panel near the vent hole. Has been done. This tack is for reducing the opening area of the vent hole at the initial stage of expansion of the driver's airbag. In Patent Document 3, tacks are provided at two locations in the circumferential direction of the rear panel.

Japanese Unexamined Patent Publication No. 2016-141279 U.S. Pat. No. 8,608,199 JP-A-2015-58919

In the driver's seat airbag of Patent Document 1, since V-shaped notches are provided at two locations facing each other in the diameter direction of the rear panel, the shape of the rear panel in the expanded state is short in the diameter direction. , It tends to be an elliptical cone with a major axis in the direction orthogonal to it, and the stability of the expanded form is insufficient.

In Patent Document 2, since the tack portion is provided only near the peripheral edge of the rear panel, the inflated shape of the driver's seat airbag is substantially the same on the front panel side and the rear panel side.

The present invention is an airbag for a driver's seat in which the distance from the sewn portion to the rear end of the rear panel is larger than the distance from the sewn portion between the front panel and the rear panel to the frontmost occupant surface in the expanded state. It is an object of the present invention to provide a driver's seat airbag having excellent morphological stability on the rear panel side in the completed state.

The driver's seat airbag of the present invention is a driver's seat airbag in which the peripheral edges of the front panel and the rear panel are connected to each other, and the rear panel has three or more peripheral edges to reduce the circumferential length. It is characterized in that a length reduction portion is provided.

In one aspect of the present invention, the peripheral length reduction portion is a notch portion provided from the peripheral edge of the rear panel toward the center side, and the side sides of the notch portion are connected to each other.

In one aspect of the present invention, the peripheral length reduction portion comprises a tack portion.

In one aspect of the present invention, a first tether is provided that connects the occupant facing surface of the driver airbag and the rear end of the driver airbag. In one aspect of the invention, the first tether is configured to increase in length when a predetermined or greater tension is applied.

In one aspect of the present invention, the cutout portion has a narrow portion in the middle portion in the radial direction of the rear panel in which the distance between the side surfaces is smaller than that on the center side of the rear panel, whereby the expansion is completed. A constriction is formed in the driver's airbag.

In one aspect of the present invention, a second tether is provided to reduce the diameter of the constricted portion.

In one aspect of the present invention, the area of the rear panel inside the suture line between the front panel and the rear panel is 1.1 to 1.3 times, preferably 1.15 times the area of the front panel inside the suture line. ~ 1.2 times.

The driver's seat airbag device of the present invention includes the driver's seat airbag of the present invention and an inflator that inflates the driver's seat airbag.

In the driver's seat airbag of the present invention, since the peripheral portion of the rear panel is provided with three or more peripheral length reduction portions, the peripheral length reduction amount by one peripheral length reduction portion is not excessive. Therefore, it is excellent in morphological stability on the rear panel side in the expanded state.

The driver's seat airbag of the present invention has a bowl shape in which the circumference of the rear panel is reduced by the circumference reduction portion, and the airbag diameter at the completion of expansion is not increased. The thickness can be increased.

It is a top view of the panel of the driver's seat airbag which concerns on embodiment. It is a perspective view of the expansion completion state of the driver's seat airbag which concerns on embodiment. FIG. 2 is a sectional view taken along line III-III of FIG. It is a vertical sectional view of the driver airbag in FIGS. 1 to 3 in the expanded state. It is a top view of the rear panel which concerns on another embodiment. It is a perspective view of the rear panel which concerns on still another Embodiment. FIG. 6 is a sectional view taken along line VII-VII of FIG. It is a vertical cross-sectional view of the expansion completion state of the driver's seat airbag which concerns on still another Embodiment. It is a front view of a tether belt. It is a top view of the rear panel of still another embodiment. It is a vertical sectional view in the expanded state of the driver's seat airbag using the rear panel of FIG. It is a top view of the rear panel of still another embodiment. It is a vertical sectional view in the expanded state of the driver's seat airbag using the rear panel of FIG.

Hereinafter, embodiments will be described with reference to the drawings.

1 to 4 show the driver airbag 1 according to the first embodiment. The airbag 1 includes a front panel 2 forming an occupant facing surface and a rear panel 3 forming a rear surface opposite to the occupant facing surface. The front panel 2 is composed of a circular panel (base cloth).

The rear panel 3 is provided with notches 4 at four locations on the peripheral edge of the circular panel. The notch 4 is provided at an equally divided position in the circumferential direction of the rear panel 3. In this embodiment, the notch 4 is V-shaped and has a pair of side sides 4a and 4b that are closer to the center side of the rear panel 3.

An inflator opening 5 is provided in the center of the rear panel 3, and a small hole 6 for inserting a bolt is provided around the inflator opening 5. A vent hole 7 is provided on the central side of a predetermined distance from the peripheral edge of the rear panel 3. The front panel 2 is circular. The area of the rear panel 3 inside the suture line between the front panel 2 and the rear panel 3 is 1.1 to 1.3 times the area of the front panel 2 inside the suture line, particularly 1.15 to 1.2. It is preferably doubled.

The rear panel 3 is formed into a bowl shape by suturing the side sides 4a and 4b of the notch 4 with suture thread 8. The diameter of the outer peripheral edge of the bowl-shaped rear panel 3 is substantially the same as the diameter of the circular front panel 2. The driver's seat airbag 1 is configured by suturing the peripheral edge of the bowl-shaped rear panel 3 and the peripheral edge of the front panel 2 with suture thread 9 (see FIG. 4).

The driver seat airbag 1, since the rear panel 3 has a cup-shaped, as in FIG. 4, a distance L ₁ from the sewn portions of the rear panel 3 and the front panel 2 in a state in which the completed inflated to the front the front panel compared with, a large distance L ₂ to the airbag 1 rear driver's seat from the suture engaging portion. Therefore, the expansion thickness L ₁ + L ₂ of the driver airbag 1 is larger than the expansion thickness of the driver airbag using a circular panel having the same diameter as the front panel as the rear panel. It is preferable that L ₂ is 1.5 to 4 times that of L ₁ and particularly 2 to 3 times.

Further, since the driver's seat airbag 1 is provided with four notches 4 on the rear panel 3, it has an expanded form on the rear panel 3 side as compared with the driver's seat airbag having only two notches. Excellent stability.

In the above embodiment, the rear panel 3 is provided with notches 4 at four locations, but the rear panel 3 may be provided at three locations as in the driver airbag 10 of FIG. Also in FIG. 5, the cutout portion 4 is provided at a position equally divided in the circumferential direction of the rear panel 3. Other configurations of the driver's seat airbag 10 are the same as those of the driver's seat airbag 1, and the same reference numerals indicate the same parts. Although not shown, the cutouts 4 may be provided at five or more locations. The number of notches 4 is preferably about 3 to 6. The depth of the notch 4 (the radial length of the rear panel 3) is preferably about 30 to 75%, particularly about 50 to 60% of the radius of the rear panel 3, but is not limited thereto.

In the above embodiment, the notch 4 is V-shaped, but it may be U-shaped, semi-circular or semi-elliptical, or Ω-shaped with a narrow inlet side.

In the above embodiment, the rear panel 3 is provided with the notch 4, and the side sides 4a and 4b of the notch 4 are sewn to form the rear panel 3 in a bowl shape. However, as shown in the rear panel 3A of FIG. A bowl shape may be formed by providing tack portions 11 at three or more locations on the peripheral edge of the circular panel not provided with.

A part of the peripheral edge of the circular panel is pinched toward the center side of the rear panel 3A, and the tack portion 11 is formed by suturing the base portion of the picked up portion with the suture thread 12.

In FIG. 6, the tack portions 11 are provided at four locations, but may be three locations or five or more locations. The number of tack portions 11 is preferably about 3 to 6.

In the present invention, as shown in the driver airbag 1'in FIG. 8, a first tether 13 may be provided that connects the peripheral portion of the inflator opening 5 of the rear panel 3 and the occupant facing surface of the front panel 2. The tether 13 is attached to the front panel 2 and the rear panel 3 by suture threads 13a and 13b.

The first tether may be of a type in which the length is short at the initial stage of expansion of the driver's seat airbag and the length is increased at the later stage. FIG. 9 shows an example of such a tether.

The first tether 14 of FIG. 9 is provided with a large portion 14a extending in a direction orthogonal to the longitudinal direction in an intermediate portion in the longitudinal direction, and the large portion 14a is provided with a large portion 14a in a direction orthogonal to the longitudinal direction. A cleaveable portion 14b extending to the surface is provided.

Since the tension applied to the tether 14 is small at the initial stage of expansion of the driver's airbag, the cleaving portion 14b does not cleave and the total length of the tether 14 is relatively short. In the latter stage of expansion near the completion of expansion, the tension applied to the tether 14 increases, the dissociable portion 14b cleaves, and the total length of the tether 14 increases.

A first tether that can be increased in length other than the tether provided with the cleaving portion may be used. For example, although not shown, the tether may be folded in the middle and sewn with a tether. In this case, the tether does not cut at the initial stage of expansion, and the tether is relatively short. When the tension applied to the tether increases in the later stages of expansion, the tether ruptures and the length of the tether increases.

10 and 11 show the driver airbag 18 according to still another embodiment, FIG. 10 is a plan view of the rear panel, and FIG. 11 is a vertical cross section of the driver airbag in the expanded state. It is a figure.

The airbag 18 includes a front panel 19 forming an occupant facing surface and a rear panel 20 forming a rear surface opposite to the occupant facing surface. The front panel 19 is made of a circular panel (base cloth).

The rear panel 20 is provided with notches 21 and 22 at four locations on the peripheral edge of the circular panel. The cutouts 21 and 22 are provided at four equal parts in the circumferential direction of the rear panel 20. The two first notches 21 and 21 face each other in the radial direction of the rear panel 20. The two second notches 22, 22 face each other in the radial direction of the rear panel 20. In this embodiment, the second notch 22 is V-shaped and has a pair of side sides 22a and 22b that are closer to the center side of the rear panel 20.

The first notch 21 has a pair of side sides 21A and 21B. The side sides 21A and 21B are curved, and the side sides 21A and 21B are close to each other in the middle portion in the radial direction of the rear panel 20. As a result, the first notch 21 is formed with an inner portion 21a on the center side of the rear panel 20, an inlet portion 21c on the inlet side, that is, an outer peripheral side of the rear panel 20, and a narrow portion 21b between the two. .. The minimum width of the narrow portion 21b is smaller than the maximum width of the back portion 21a.

An inflator opening 25 is provided in the center of the rear panel 20, and a small hole 26 for inserting a bolt is provided around the inflator opening 25. A vent hole 27 is provided on the central side of a predetermined distance from the peripheral edge of the rear panel 20.

In this embodiment, one or two or more (for example, two in the orthogonal direction) second tethers 23 extending in the radial direction of the rear panel 20 are provided. Both ends of the tether 23 are sewn to the rear panel 20 by sutures 23a. The sewing position between the end of the tether 23 and the rear panel 20 is the same radius as the notch 22b with respect to the center of the rear panel 20 in the radial direction of the rear panel 20.

The rear panel 20 is formed into a bowl shape by suturing the side sides 21A and 21B of the first notch 21 and the side sides 22a and 22b of the second notch 22 with sutures. The diameter of the outer peripheral edge of the bowl-shaped rear panel 20 is substantially the same as the diameter of the circular front panel 19. The driver's seat airbag 18 is configured by suturing the peripheral edge of the bowl-shaped rear panel 20 and the peripheral edge of the front panel 19 with suture thread 29.

Since the rear panel 20 of the driver airbag 18 is also sewn in a bowl shape, as shown in FIG. 11, the distance from the sewn portion between the rear panel 20 and the front panel 19 to the front surface of the front panel in the fully expanded state is compared with the distance. Therefore, the distance from the sewn portion to the rear end of the driver airbag 18 is large. Therefore, the expansion thickness of the driver airbag 18 is larger than the expansion thickness of the driver airbag using a circular panel having the same diameter as the front panel as the rear panel.

Further, since the driver's seat airbag 18 is provided with four notches 21 and 22 on the rear panel 20, the rear panel 20 side is expanded as compared with the driver's seat airbag having only two notches. Excellent morphological stability.

Further, in this embodiment, the narrow portion 21b is provided in the first notch portion 21 and the second tether 23 is provided, so that the driver airbag in the expanded state is completed. A constriction portion P is provided at 18. That is, the diameter of the driver's seat airbag 18 in the constricted portion P is larger than the diameter of the first maximum diameter portion F on the occupant side of the constricted portion P and the second maximum diameter portion E on the steering wheel 30 side of the constricted portion P. Is also small. The second maximum diameter portion E on the steering wheel 30 side is located closer to the occupant than the steering wheel 30, and its diameter is larger than the diameter of the steering wheel 30. Therefore, the second maximum diameter portion E covers the steering wheel 30 from the occupant side. By engaging the second maximum diameter portion E with the steering wheel 30 in this way, the posture of the driver's seat airbag 18 at the time of an oblique collision is stabilized.

The driver airbag 18'in FIGS. 12 and 13 is further provided with a narrow portion 21b so that the constricted portion P is formed at a position where the constricted portion P overlaps the steering wheel 30 from the inner peripheral side and avoids spokes (not shown). It is provided on the center side of the rear panel 20'. As shown in FIG. 13, the constricted portion P engages with the steering wheel 30 from the inner peripheral side. Further, the second maximum diameter portion E is located on the anti-occupant side of the steering wheel 30. Other configurations of the driver airbag 18'are the same as those of the driver airbag 18, and the same reference numerals have the same parts.

The driver's seat airbag 18'also has the same effect as the driver's seat airbag 18. In the driver's seat airbag 18', the steering wheel 30 is sandwiched between the second maximum diameter portion E of the driver's seat airbag 18'and the portion on the occupant side of the constricted portion P, so that the steering wheel 30 collides with the driver's seat. The stability of the driver airbag 18'at the time is high.

The driver airbags 18 and 18'in FIGS. 10 to 13 are provided with two second notch portions 21 and two second notch portions 22, but the number of each is limited to these. Instead, for example, only three or more first notch portions 21 may be provided.

The above embodiment is an example of the present invention, and the present invention may be an embodiment other than the above.

1,1', 10,18,18'Driver's airbag 2,19 Front panel 3,20 Rear panel 4,21,22 Notch 5,25 Inflator opening 7,27 Vent hole 11 Tuck part 13,14, 23 Tether 21b Narrow width part

Claims (8)

In a driver airbag that connects the periphery of the front panel and the rear panel
The rear panel is provided with peripheral length reducing portions for reducing the peripheral length at three or more locations on the peripheral edge .
The driver's seat airbag is characterized in that the area of the rear panel inside the suture line between the front panel and the rear panel is 1.1 to 1.3 times the area of the front panel inside the suture line. .. The driver's seat airbag according to claim 1, wherein the peripheral length reducing portion is a notch portion provided from the peripheral edge of the rear panel toward the center side, and the side sides of the notch portion are connected to each other. .. The driver's seat airbag according to claim 1, wherein the peripheral length reducing portion comprises a tack portion. The operation according to any one of claims 1 to 3, wherein a first tether for connecting the occupant facing surface of the driver airbag and the rear end of the driver airbag is provided. Seat airbag. The driver's seat airbag according to claim 4, wherein the first tether increases in length when a tension equal to or higher than a predetermined value is applied. In claim 2, the cutout portion has a narrow portion in the middle portion in the radial direction of the rear panel, in which the distance between the side surfaces is smaller than that on the center side of the rear panel, whereby the driver's seat in the expanded state is completed. An airbag for the driver's seat, which is characterized in that a constriction is formed in the airbag. The driver's seat airbag according to claim 6, wherein a second tether for reducing the diameter of the constricted portion is provided. An airbag device for a driver's seat, which comprises the airbag for the driver's seat according to any one of claims 1 to 7 and an inflator for inflating the airbag for the driver's seat.

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