JPH04146838A - Bag body for air bag - Google Patents

Abstract

PURPOSE:To produce an inexpensive air bag imparted with stable and reliable air non-permeability by causing an unwoven fabric to be closely contacted and integrated, by melting, with an inward portion of a bag body prepared by using a synthetic fiber textile as a base member. CONSTITUTION:An air bag body 1 is produced using a laminated cloth sheet which is prepared by laminating a synthetic fiber textile 2a, a polyolefin-based resin film 3, and an unwoven fabric 4 so that they may be located on an outward passenger side of the bag body 1, on an immediately inward side therefrom and on a further inward side therefrom in this order when mounted to a vehicle body. On the other hand, at a vehicle body side, i.e., a side facing a handle, a synthetic fiber textile 2b is used. The resulting lamination at an inner peripheral end portion 6 thereof is unified for bondage by being sewn in plural sewing-strand rows. Further, an inflator mount opening 5 is formed at a central portion of the driver-side textile 2b. According to this structure, the air permeation of the textile is prevented by the polyolefin-based resin film 3. On the other hand, the presence of the unwoven fabric 4 prevents the high-pressure gas during the air-bag system operation from directly impinging upon the polyolefin-based resin film 3 which is therefore prevented from being damaged by a high-temperature gas.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a bag body for an air bag. More specifically, the present invention relates to an airbag body that has a novel structure and can be usefully used as an airbag for a driver's seat, a passenger's seat, or a rear seat.

In recent years, air bag systems have been put into practical use as a safety device for protecting occupants to prevent personal injuries caused by automobile collisions. The airbag system consists of a sensor that detects a car collision, a gas generator (inflator) that inflates the bag based on a signal from the sensor, and an airbag that inflates with gas and absorbs the impact on the occupants in the event of a collision. .

Airbags vary in shape and size depending on their purpose, i.e., driver seat, passenger seat, or rear seat, but they are formed as a bag body, and the bag body is provided with an inflator mounting hole and, if necessary, a vent hole. .

The airbag body is usually formed by sewing a fabric made of synthetic fiber or by weaving a hollow weave structure in order to maintain durability when inflated by gas. On the other hand, when the airbag system is activated, high gas pressure is applied to the airbag from the inside. In this case, the synthetic fiber fabric alone has a high permeability to the generated gas, so that the generated gas can already escape from the fabric within the time required to protect the occupant, and as a result, the necessary inflation of the airbag cannot be maintained. Therefore, in conventionally known airbag bodies, as disclosed in JP-A No. 49-47692, the inside and/or outside of the bag is coated with an elastomer such as chloroprene or silicone to prevent ventilation. ing.

[Problem to be solved by the invention]

As previously stated, the airbag body using a base material coated with a conventionally known elastomer has an excellent structure in terms of keeping the bag in an inflated state within a predetermined period of time through air-proof treatment, but the bag has a heavy basis weight. In addition, stable impermeability may not be achieved due to pinholes and the like that occur during the coating process. Furthermore, coating a fabric made of synthetic fibers with an elastomer requires a high cost, resulting in an increase in the cost of the entire airbag body.

The present invention solves the above-mentioned problems of conventionally known airbag bodies, and provides an airbag body that can provide stable and reliable air impermeability and can be manufactured at low cost. The purpose is to

[Means to solve the problem]

The object of the present invention is to provide a bag body based on a woven fabric made of synthetic fibers, in which a nonwoven fabric is closely integrated with at least a portion of the inside of the bag body through a polyolefin resin film by melting the polyolefin resin. This is achieved by an airbag body.

An airbag body having the above-described structure can be used as an airbag body for a driver's seat, a passenger's seat, or a rear seat by appropriately selecting its shape and size.

Also, the part where the nonwoven fabric is closely integrated with the inside of the bag through the polyolefin resin film may be only a part of the bag, for example, the part that faces the passenger when attached to the car body, or it may be the inside of the bag. It may be all of them. In the former case, the portion of the airbag body facing the vehicle body has gas permeability, and a vent hole can be omitted in this type of airbag body. In the latter case, since the entire bag is impermeable, it is necessary to provide a vent hole in the portion of the airbag that faces the vehicle body.

In the airbag body of the present invention, the polyolefin resin film prevents the air permeability of the fabric.

On the other hand, since a non-woven fabric is placed on the outside of the polyolefin resin film (on the inside when viewed from the bag body), high-pressure gas when the airbag system is activated is prevented from directly hitting the polyolefin resin film. The system resin film will not be damaged. With this structure, a polyolefin resin that melts at a relatively low temperature is melt-extruded into a sheet shape, a synthetic fiber fabric is laminated on one side of the sheet-shaped molten resin, and a nonwoven fabric is laminated on the other side at the same time or one after another, and then press treatment is performed. It is possible to impart impermeability to the airbag body by this simple method. Therefore, the airbag body of the present invention can be manufactured at a lower cost than conventionally known elastomer coated bags. The airbag body is folded and stored when attached to the vehicle body. For this purpose, in the case of a conventionally known elastomer coated bag, an anti-blocking agent is added to the applied elastomer so that the air bag can be rapidly inflated. On the other hand, in the airbag body of the present invention, since the surface of the bag body is made of woven or non-woven fabric, it does not have adhesive properties, and therefore does not require the use of expensive anti-stick agents.
It is possible to provide an airbag body that can be reliably inflated.

As the synthetic fibers used for weaving the bag body of the airbag of the present invention, high-strength synthetic fiber multifilaments such as polyamide multifilament and polyester multifilament are preferably used, but are not limited to these. As the nonwoven fabric, it is preferable to use a nonwoven fabric made of long or short fibers such as polyamide fibers or polyester fibers. The basis weight of non-woven fabric is 20g/m'~25g
/rnO is preferably used.

In addition, as polyolefin resins, high density polyethylene resins, low density polyethylene resins, polypropylene resins,
Ethylene propylene copolymer resin, ethylene vinyl acetate copolymer resin, ionomer resin, etc. can be used.

J of the part where the nonwoven fabric is closely integrated with the polyolefin resin film of the air bag body obtained in this way.
Air permeability by IS-L-1096 Frazier method is 2cc
/c++f/min or less, the air impermeability can be sufficiently maintained, and the basis weight of this part can be made to be 280 g/m' or less.

〔Example〕

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail below with reference to the accompanying drawings showing an example of an air bag body of the present invention.

FIG. 1 shows an example in which the airbag body according to the present invention is used as an airbag for a driver. The airbag body 1 shown in FIG. 1 has a synthetic fiber fabric 2a on the outside, a polyolefin resin film 3 on the inside, and a nonwoven fabric 4 on the inside, on the side facing the passenger when attached to the vehicle body. A synthetic fiber fabric 2b is used on the vehicle body side, in this case, the side facing the steering wheel, and each peripheral portion 6 is sewn and joined using multiple rows of sewing threads 7. An inflator attachment opening 5 is provided in the center of the driver side fabric 2b.

FIG. 2 shows another example of the airbag body for a driver according to the present invention. The driver air bag body 11 shown in FIG. 2 differs from the embodiment shown in FIG. 1 in that a laminated cloth is also used on the side facing the driver. That is, on the side facing the passenger, the synthetic fiber fabric 12a is placed on the outside, and the polyolefin resin film 13a1 is placed on the inside, and the nonwoven fabric 1 is placed on the inside.
4a is used, a synthetic fiber fabric 12b is placed on the outside facing the driver, a polyolefin resin film 13b is placed on the inside, and a non-woven fabric 14b is placed on the inside.
The peripheral portions 16 of each of the laminated fabrics are sewn and joined using multiple rows of sewing threads 17.

An inflator mounting opening 15 is provided in the center of the laminated fabric on the driver side, and a plurality of vent holes 18 are provided.

FIG. 3(A) shows a perspective view of an example of an airbag body for a passenger seat. In the bag body 21 for a passenger seat air bag according to the present invention shown in the cross-sectional view (FIG. 3 (B)) taken along the plane indicated by arrow II [B-IB in Figure 3 (A), the air bag bag body is attached to the vehicle body. The synthetic fiber fabric 22 is placed on the outside on the side facing the passenger when installed on the vehicle, and a polyolefin resin film 23 and a nonwoven fabric 24 are laminated on the inside. On the other hand, the portion where the vent hole 27 is provided is formed of the synthetic fiber fabric 22. End face cloths 28a, 2 of the passenger seat airbag body 21 shown in FIG.
8b may also have a laminated structure only on the upper side. The airbag body 21 for the passenger seat shown in FIGS. 3 and 4 has a partially laminated structure, and this is the end portion 25a.

25b with multiple rows of sewing threads 26, a polyolefin resin film and a nonwoven fabric may be partially laminated on the inside of the synthetic fiber fabric 22, or the laminated fabric and the synthetic fiber fabric may be prepared separately. After that, the two may be joined by sewing or the like (not shown).In addition, in the passenger seat airbag body shown in FIG.
All of the constituent fabrics are woven fabrics, polyolefin resin layers,
It may also be formed from a laminated fabric made of non-woven fabric.

〔Effect of the invention〕

The airbag body according to the present invention has a laminated structure in which the fabric is placed on the outside and the nonwoven fabric is closely integrated with all or part of the inside of the fabric through a polyolefin resin film, so the airbag body is impermeable to air. The nonwoven fabric protects the film that imparts properties from high-temperature gases, and since the film is free from pinholes, stable and reliable impermeability can be achieved. In addition, since the amount of resin can be reduced compared to coating treatment, the weight of the resulting airbag body can be reduced, and
The cost of the airbag obtained through inexpensive processing can be reduced.

[Brief explanation of drawings]

FIG. 1 is a sectional view showing an example of the airbag bag of the present invention used as a driver's airbag bag, and FIG. 2 is a sectional view showing another example of the driver's airbag bag of the present invention. FIG. 3(A) is a perspective view showing an example of a bag body for an airbag for a passenger seat; FIG.
FIG. 3(B) is a sectional view taken along line IB-I [IB in FIG. 3(A), showing an example of the bag body for a passenger seat airbag of this invention. 1.11... Driver airbag bag, 2a
, 2b, 12a, 12b, 22...Synthetic fiber fabric, 3
．． 13a 13b, 23... Polyolefin resin film, 4.14a, 14b, 24... Nonwoven fabric, 5.15
...Inflator installation port, 18...Vent hole, 21...Passenger seat air bag body. Engraving of the drawings (no change in content) Figure ] 8 ] 5 ] 8 Figure (A) (B) Written amendment of cause procedure (method) % formula % Indication of the case Patent Application No. 269324, 1990 2゜Name of the invention Airbag bag body 3゜Relation to the person making the amendment Patent name (003) Asahi Kasei Kogyo Co., Ltd. 4゜Agent's address: 5゜8-10-chome, Toranomon, Minato-ku, Tokyo 105 Date of amendment order January 22, 1991 (dispatch mill) 6゜7゜8゜Object of amendment 1) Specification 2) Contents of drawing amendment 1) Engraving of specification (no change in content) 2) Drawings Engraving (no change in content) List of attached documents 1) Engraved specification 2) 1 copy of engraving drawings

Claims (1)

[Claims] 1. A bag body made of a woven fabric made of synthetic fibers,
A bag body for an air bag, in which a nonwoven fabric is closely integrated with at least a portion of the inside of the bag body through a polyolefin resin film by melting the polyolefin resin.