GB2290061A

GB2290061A - Air bag with flaps round inflator opening

Info

Publication number: GB2290061A
Application number: GB9511667A
Authority: GB
Inventors: Ryoichi Yoshida; Noriyuki Kosugi; Eiji Yanagi; Yoshihiko Tanaka; Akira Kokeguchi; Tadayuki Atoh; Yoshihiko Minami
Original assignee: Takata Corp
Current assignee: Takata Corp
Priority date: 1994-06-10
Filing date: 1995-06-08
Publication date: 1995-12-13
Anticipated expiration: 2015-06-08
Also published as: GB2290061B; DE19521071A1; JPH07329687A; DE19521071B4; GB9511667D0

Description

2290061

Title of the invention

Air Bag Field of the Invention and Related Art Statement

The present invention relates to an air bag of an air bag device for protecting an occupant in a passenger seat or a rear seat when a vehicle comes into collision.

A conventional air bag for a passenger seat will be described with reference to Fig.13.

The air bag 1 for a passenger seat has an opening 2 for introducing gas from an inflator (not shown) which is disposed at the rear portion of the air bag 1. The air bag 1 is made of cloth and provided with flaps 3 which are made by impregnating synthetic resin or piling up and sewing reinforcing cloths on the periphery of the opening 2. The flaps 3 are provided with a plurality of through holes for inserting bolts or rivets for connecting the air bag 1 to a container (not shown) of the air bag device.

The air bag 1 is made by sewing the peripheries of side panels 7 on the periphery of a long centre panel 6 as shown in Fig. 14.

The side panels 7 are each provided with a vent hole 5 previously. When the occupant plunges into the air bag 1, the vent holes 5 allow gas to flow out to absorb an impact applied to the occupant.

In the conventional air bag for a passenger seat as mentioned above, it takes many man-hours to sew the side 1 panels 7 on the centre panel 6 of a predetermined size because of a three- dimensional sewing.

That is, when each of the side panels 7 is sewed on the centre panel 6, the peripheries of them are superposed on each other and sewed by a sewing machine. For superposing the peripheries, it is necessary to curve the centre panel 6 along the periphery of the side panel 7. Therefore, it is difficult to superpose the edge portion of the centre panel 6 on each of the peripheries of the side panels 7. Because the centre panel 6 and the side panels 7 are sewed up with curving the centre panel 6, it is difficult and needs a lot of time and labour to sew them up.

When one of side panels is sewed on the centre panel after the other side panel has been sewed on the centre panel, it is particularly difficult to sew them up because the other side panel sewed up is bulky and is an obstacle to sew them up.

Object and Summary of The invention

It is therefore an object of the present invention to provide an air bag which can be made easily and of which production cost can be remarkably reduced.

An air bag according to the present invention relates to an air bag of an air bag device for a passenger seat or a rear seat and is characterized by that the air bag is made by superposing two panels and connecting the peripheral portions of the panels, the air bag is provided with an opening for introducing gas from an inflator at the rear end 2 i, il.

thereof, and the panels are integrally provided with flaps surrounding the opening to fix the air bag to a container of the air bag device.

Preferably, the container has a rectangular front opening, and the air bag is characterized by that f irst f lap is extended from a lower panel to dispose along one side edge of the front opening of the container, and second, third, and fourth flaps are extended from an upper panel to dispose along the other three side edges of the front opening of the container.

Since the air bag of the present invention Is made by superposing panels such as two sheets of cloth and connecting the peripheries of them by sewing or the like, the air bag is produced easily.

Flaps are extended from the lower panel and the upper panel integrally, so that the air bag can be f ixed to a container using the flaps.

Brief Description of the Drawings

Fig 1 is a perspective view of an air bag according to an embodiment of the present invention; Fig 2 is a section view of the air bag according to the embodiment; Fig 3 is an exploded perspective view of the air bag according to the embodiment; Fig 4 is a perspective view of a part of the air bag according to the embodiment; 3 Fig 5 is a perspective view of a part of the air bag according to the embodiment; Fig 6 is a perspective section view taken along VI-VI line in the Fig 5; Fig 7 is a side view of the inside of a vehicle mounted with an air bag device according to the embodiment; Fig 8 is a side view of the inside of the vehicle mounted with the air bag device according to the embodiment; Fig 9 is a side view of the inside of the vehicle mounted with the air bag device according to the embodiment; Fig 10 is a side view of the inside of a vehicle mounted with an air bag device according to another embodiment; Fig 11 is an enlarged section view of a portion XI in Fig 10; Fig 12 is an exploded perspective view of an air bag 18A according to an embodiment; Fig 13 is a perspective view of a conventional air bag for a passenger seat; and Fig 14 is an exploded view showing the structure of the conventional air bag for a passenger seat.

Detailed Description of The Preferred Embodiment

Embodiments will now be described with reference to the attached drawings. Figs 1-6 are explanatory views of an air bag according to an embodiment of the present invention and Figs 7-9 are side views showing the inside of a vehicle mounted with an air bag device according to the embodiment.

4 1 Q i As shown in Fig 9, the air bag device 14 is mounted in an instrument panel 12 of the vehicle 10. The air bag device 14 has a casing 16, an air bag 18 folded and accommodated in the casing 16, an inflator 20 for generating gas for deploying the air bag 18, and a lid 22 covering the casing 16. The lid 22 has one side connected to the casing 16 to allow the lid to rotate into the cabin 24 of the vehicle. The other side of the lid 22 opposite to the one side is connected to the casing 16 such that it comes apart from the casing 16 upon pushing force of the air bag 18 when the inflator 20 operates to deploy the air bag 18.

The air bag 18 is f ormed in an envelope shape by sewing up two sheets of cloth which are a lower panel 34 at the lower side thereof and an upper panel 36 at the upper side thereof, as shown in Figs 1-6. The air bag 18 is structured to extend toward the portion about the corner 32 where a seat cushion 28 and a seat back 30 of a seat 26 in the vehicle 10 cross each other.

The air bag 18 has an opening 38 for introducing gas from the inflator 20 at its rear portion. Flaps 42, 44, 46 and 48 are disposed on the periphery of the opening 38 and are connected to the casing 16. A vent hole 40 may be disposed in the lower panel 34 or in the upper panel 36.

The panels 34 and 36 are formed in a shape extending longer in the longitudinal direction than the width direction of the vehicle 10. The opening 38 in the air bag 18 is positioned near the front of the vehicle.

The first flap 42 is integral with the lower panel 34. The second, third and fourth flaps 44, 46 and 48 are integral with the upper panel 36.

The flaps 42, 44, 46, 48 are provided with a plurality of through holes (circular holes or slits may be employed) 50 for inserting bolts or rivets.

Each vent hole 40 is provided with a ring-shaped patching cloth 54 sewed on the periphery thereof. The panels 34 and 36 are, as shown in Fig 3, superposed each other on a work bench (not shown) of a sewing machine. The peripheral portions of the panels 34 and 36 are, as shown in Fig 2, sewed up securely with a thread 58.

It is quite easy to sew them up because the two panels 34 and 36 are sewed in a state that the panels 34 and 36 are superposed on the flat work bench as mentioned above.

The panels 34 and 36 are preferably structured so as to cross aslant textures of the panels to each other.

When the vehicle mounted with the air bag device 14 as structured above comes into collision, the inflator 20 spouts out gas to deploy the air bag 18. The lid 22 is pushed by the air bag 18 deploying and opens toward the cabin 24 of the vehicle. The air bag 18 then extends into the cabin 24 of the vehicle, as shown in Fig 7. The air bag 18 extends toward the portion about the corner 32 where the seat cushion 28 and the seat back 30 cross each other, as shown in Fig 8. The air bag 18 finally touches the waist 60 of the occupant to restrain the waist 60 of the occupant.

6 9 X I- As a result of various kinds of experiments, it is proved that the air bag 18 restraining the waist 60 can protect enough the occupant as well as a conventional air bag deployed widely in front of the upper part of the occupant, such as a part from the chest to the head, of the occupant. The air bag device 14 has an effect of restricting a forward movement of the lower part of the occupant without a seat belt when the vehicle comes into collision.

The air bag 18 of the air bag device 14 has a small volume as compared with a conventional air bag which deploys widely in front of the upper part of the occupant. Therefore, the air bag 18 is completely deployed in a short time. Furthermore, it is possible to reduce the capacity of the inflator 20.

The air bag 18 made by sewing up two panels 34 and 36 is employed in the above embodiment, but the invention is not limited thereto. An air bag according to the present invention may be an air bag such as a an air bag 18A shown in Fig 12 which is structured by folding one sheet of panel 62 in two and sewing up the peripheral portions of an upper panel 62a and a lower panel 62b.

Fig 10 is a side view of the inside of a vehicle mounted with an air bag device according to another embodiment of the present invention and Fig 11 is an enlarged section view of a portion XI in Fig 10.

In the air bag 18B used for this embodiment, one part of the lower side surf ace is lapped and sewed up with a 7 thread 64. The thread 64 has characteristics to snap when a tensile force applied to the thread 64 exceeds a predetermined value due to an inner pressure of the air bag 18B exceeding a predetermined value.

In the air bag device as structured above, the air bag 18B is deployed by an operation of the inflator. The thread 64 does not snap until the air bag 18B becomes in an intermediate deployed state as shown in Fig 11. After the intermediate deployed state, the inner pressure in the air bag 18B is increased so that the tensile force applied to the thread 64 exceeds the strength of the threat 64, thereby the thread 64 snaps. The tip portion of the air bag 18B extends toward the seat cushion 28 f irst as shown by the arrow 99 and, by a snap of the threat 64, the air bag then extends toward the portion about the corner 32 where the seat cushion 28 and the seat back 30 meet each other, as shown by the arrow 100.

The air bag according to the present invention is suitable for a topmount-type air bag device.

The top-mount-type air bag device is mounted in the upper part of the instrument panel.

The air bag device is mounted on the instrument panel 12 in the above mentioned embodiments, the air bag device may be mounted also on the seat back 30 for protecting an occupant in a rear seat.

The panels are made of cloth in the above mentioned embodiments, the panels may be instead made of synthetic resin sheet or woven synthetic resin fibres.

a 9 1P Z The upper panel and the lower panel are connected by sewing up, these panels may be connected also by adhesion or heat sealing.

As mentioned above, according to the present invention, an air bag can be made easily and the production cost of an air bag for a passenger seat or an air bag for a rear seat can be remarkably reduced.

The specification refers to the disclosure of application Serial No. 322, 515 filed on October 14, 1994.

9

Claims

WHAT IS CLAIMED IS:

1. An air bag of an air bag device for a passenger seat or a rear seat comprising: a lower panel and an upper panel, said panels being superposed and connected at the peripheral portionS thereof, an opening for introducing gas from an inflator being disposed at a rear end of said air bag, and flaps being integral with the panels and surrounding said opening to fix the air bag to a container of an air bag device.

2. An air bag as claimed in claim 1, wherein said container has a rectangular front opening, a f irst f lap is extended from said lower panel to dispose along one side edge of said front opening of said container, and second, third, and fourth flaps are extended from said upper panel to dispose along the other three side edges of said front opening of said container respectively.

3. An air bag as claimed in claim 1 or claim 2, wherein said lower panel and said upper panel are not integral.

4. An air bag as claimed in claim 1 or claim 2, wherein said panels are formed by folding back a long sheet of a panel.

Y_ 1 1 X1

5. An air bag as claimed in any one preceding, wherein the peripheral portions of said panels are connected by at least one of the methods including sewing, bonding, and heat sealing.

6. An air bag as claimed in any one preceding claim wherein edges of said flaps are joined to each other to form a rectangular opening prior to connecting to a casing of an air bag device.

7. An air bag according to claim 6 wherein said edges are joined by a method selected from the group comprising sewing, bonding, and heat sealing.

8. An air bag substantially as herein before described with reference to the accompanying specification and Figures 1 - 6; or Figures 7 to 9; or Figures 10 and 11; or Figure 12 or the drawings.