JPH0820298A - Air bag and manufacture thereof - Google Patents

Abstract

PURPOSE:To provide an impact resisting-absorbing bag and a method of manufacturing it with high productivity at low cost. CONSTITUTION:Gas exhaust filter foundation 6 with an inflator fitting hole 5 is laminated on steering wheel side air bag forming foundation 4 with an inflator fitting hole 2 and at least one or more gas exhaust holes 3 bored around the inflator fitting hole 2, and these foundations 4, 6 are integrated by sewing or bonding. Occupant side air bag forming foundation 1 is then sewn or bonded to the air bag forming foundation 4 to form a bag body. The occupant side air bag forming foundation 1 is then pulled out of the inflator fitting hole of the bag body to reverse the bag body, thus forming an air bag.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a shock absorbing air bag for an automobile and a method of manufacturing the same for preventing a personal injury resulting from a vehicle accident. More specifically, it is not damaged by the high temperature gas from the inflator and the high temperature gas generating agent combustion residue, and the scattering of the combustion residue is shielded and filtered, and it has excellent impact resistance and burst resistance. The present invention relates to an easy airbag and a manufacturing method thereof.

[0002]

2. Description of the Related Art In recent years, airbags have been put into practical use as personal injury prevention devices associated with automobile collisions, and their popularity is rapidly increasing. These airbag impact absorption devices are sensors for detecting vehicle collisions. And a gas generator for explosively generating a gas for inflating the bag based on a signal from the sensor and an air bag portion for instantaneously inflating by absorbing the shock of an occupant due to filling of the generated gas. The air bag portion is generally extremely high density,
A woven or knitted fabric with a low air permeability or a woven or knitted fabric that has been subjected to an air-impermeable treatment is cut into a predetermined shape, and the outer peripheral portion thereof is sewn or adhered to form a bag having a bag-shaped space inside. At least one inflator mounting hole is formed on one surface (handle side) of the bag, and an exhaust hole for exhausting generated gas at an appropriate exhaust speed is provided, or an exhaust gas having an appropriate air permeability is provided. The woven and knitted fabric has a function (a woven and knitted fabric), and the other face is made of a woven and knitted fabric having a low air permeability.

Basic functions required of such an air bag (constituent woven or knitted fabric) are that it has sufficiently high impact strength, that it has sufficiently high (impact) tear strength, and that it has sufficiently high burst strength (pressure resistance). Sufficient heat resistance (melting point and physical properties at high temperature) Appropriate air permeability and filtration performance Excellent storageability so that it can be compactly stored when installed When gas is introduced into the air bag Is required to be developed, and in order to satisfy this required function, many devised and devised developments have been made in selection of constituent materials, constituent structure, secondary processing for reinforcement, etc. In addition, many ideas and innovations have been made in terms of streamlining the airbag manufacturing process and improving productivity.

That is, in order to satisfy the required functions of to, selection of synthetic fiber materials such as nylon 66 and polyethylene terephthalate, and spinning conditions for securing high tenacity, high knot strength, toughness, and dimensional stability. In addition to the selection of the woven and knitted fabric composition, the reinforcement method and structure (reinforcement cloth is sewn around the opening for sewing, Adhesion and reinforcement, etc.) and secondary reinforcement secondary processing (the entire surface of the reinforcing coating material, partial coating, etc.)
There are many ideas and ingenuities made in, such as selection of heat resistant synthetic fiber material suitable for satisfying the required function of
Many contrivances have been made for the selection of secondary processing that imparts additional heat resistance (such as partial coating of heat-resistant coating materials) and for the design of the structure of the bag structure. Many ideas and innovations have been made in the selection of fiber constituents (denier of constituent fibers, number of twists, etc.), woven and knitted constituents (weaving, woven density, etc.) and additional secondary processing for air permeability adjustment. In order to satisfy the required functions of ,, ~, the selection of the structure of the woven and knitted fabric and the application form of the additional secondary processing of reinforcement (the most effective partial coating method and the selection of coating material, etc.),
Many ideas and ingenuities have been made to design the bag configuration form.

As a result of the above-mentioned inventions and contrivances, in general, the structure of the shock absorbing bag portion is a woven or knitted fabric having one side (handle side) of the bag with extremely high density, low air permeability and the above-mentioned required physical properties. Alternatively, the woven or knitted fabric that has been subjected to the impermeable processing is cut into a predetermined shape, at least one inflator mounting hole is drilled to reinforce the periphery thereof, and further exhaust gas is exhausted at an appropriate exhaust speed. At least one hole is provided to reinforce the surrounding area and a filter cloth for filtering out fine powdery combustion residue of the gas generating agent is added, or this one surface (handle side) is entirely air-permeable. It is made of a surface (woven or knitted fabric) that has air permeability and is combined with another surface made of another woven or knitted fabric with low air permeability, and the outer peripheral part is sewn or bonded to form a bag shape inside. Adopted the method of making a bag with space To have.

[0006]

However, in order to reinforce the vicinity of the inflator mounting hole and the exhaust hole, an annular reinforcing cloth covering this portion is cut out, laminated and sewn or adhered to reinforce it, or The conventional method of applying the reinforcing coating process increases the number of steps, complicates the manufacturing process, lowers productivity, and contributes to cost increase. Further, in order to filter out the high temperature and fine combustion residue of the gas generating agent from the inflator and exhaust at a proper exhaust speed, the filter cloth is cut out in order to cover the exhaust hole portion with the filter cloth, and the above laminated Since it is necessary to stack it on the body or coating and integrate it by sewing or gluing, the number of steps will increase further, the manufacturing process will be complicated and productivity will deteriorate, and the types and shapes of handling base cloth will increase. However, the management of the base cloth becomes complicated, which causes a problem of further increasing the cost.

In order to solve this complicated problem, the base fabric constituting the bottom side (handle side) of the air bag having the inflator mounting hole is constructed of a woven or knitted fabric base fabric having air permeability that satisfies the gas discharging performance. However, if such a measure is taken, slipping at the sewn part will be performed when the air bag is formed by sewing the outer periphery of the woven and knitted base fabric on the occupant side (front side). Is likely to occur, and it may be difficult to obtain sufficient sewing strength, making it difficult to ensure sufficient safety and certainty.

In addition, the coating for adjusting the air permeability to lower the air permeability and the coating for imparting heat resistance and reinforcement increase the weight of the air bag and deteriorate the storability and deployability. In addition, there is a problem that the processing cost is increased due to the coating. Therefore, according to the present invention, the number of constituent members is small, the number of steps such as sewing and bonding is small, and the development of the airbag constituent member capable of manufacturing the airbag which does not require the adjustment of the air permeability by the coating and the requirement can be realized. It is earnestly desired to design various forms of components and to develop a sewing and adhesive integrated production system.
The present invention provides an impact resistant bag that solves these problems and has excellent performance, and a method for producing the bag with high productivity and low cost.

[0009]

The present invention has solved the problems by using the following means. That is, rationalization of the structure and layout of the components of the air bag, and by reducing the types and shapes of the base materials that make up the air bag as much as possible, the complexity of the base cloth management is eliminated, and the component members are laminated and sewn (bonded). ) Process is simplified, the airbag manufacturing process is simplified, and high productivity and cost reduction are possible (sewing,
We have succeeded in developing an integrated process and high-performance products. That is, in the present invention, the type of the airbag-constituting base fabric is the same as that of the front side (occupant side) airbag constituting base fabric and the bottom side (handle side) airbag constituting base fabric. One type of base cloth with air permeability, high strength, high burst strength, and high impact tear strength, the outer shape is the same, and the bottom side has an inflator mounting hole and a gas permeation hole for perforation. In addition, the reinforcement of the bottom side (handle side) air bag component base fabric and the role of both the filter material for the gas generant combustion residue and the function of adjusting the air permeation rate of the generated gas are shared. It is only necessary to prepare one type of gas exhaust filter base cloth of one shape and ring shape of size and shape that covers the hole for use, and to prepare two types of total, three shapes in total, and three component members (base cloth). Stop and write the base cloth management And rationalization.

The unification of the types and shapes of the constituent members, and the reduction in the number of parts due to compression have succeeded in significantly simplifying and rationalizing the air bag manufacturing system in which the members are laminated and combined and sewn (bonded) and integrated. Greatly contributes to productivity and production system construction and cost reduction. That is, the production of the air bag can be performed by the following simple steps. Reinforcement and air permeability adjustment are performed to cover the inflator mounting holes and the gas permeation holes of the bottom side (handle side) airbag fabric that has perforated the inflator mounting holes and the gas permeation holes. The gas exhaust filter base fabric to be carried out is laminated and arranged, and the periphery of the opening of the constituent base fabric in the laminate is sewn (bonded) and integrated to obtain a bottom surface constituent material. Next, on the front side (occupant side) air bag constituent base cloth, the surface side of this bottom surface constituent material on which the gas exhaust filter base cloth is not laminated is put together and the outer periphery is sewn (bonded) into a bag shape. The air bag member is manufactured by grasping the front side (occupant side) air bag constituent base cloth from the inflator mounting hole portion of this bag-shaped sewn product, pulling it out, reversing it and turning it over.

In the present invention, in order to further reinforce the periphery of the inflator opening, an inflator mounting hole made of the same material as that of the bottom air bag constituent base cloth and the same as that of the bottom air bag constituent base cloth is punched, Prepare a ring-shaped reinforcing cloth of a size and shape that has been punched out so that the outer circumference does not cover the generated gas permeation holes, and stack it on the gas exhaust filter base cloth when sewing the bottom surface constituent material and sew it to the bottom surface constituent material. It is also possible to produce. In this case, a component material (base cloth) having a total of four members in two types and four shapes is prepared, but the number of kinds of the constituent base material (base cloth) is 2, and the burden is not so large. Complete.

In the present invention, the explosion occurs from the inflator when the safety device (air bag) is activated,
High temperature gas accompanied by fine powdery combustion residue of gas generating agent is filtered out to keep the vehicle interior clean and prevent indoor pollution, reduce the impact on passengers and ensure safety. As a method of controlling the permeation / exhaust state of the generated gas in order to maintain the expanded state, the bottom side (handle side) of the air bag is provided with a perforated gas / permeation hole for permeation / exhaust of the generated gas. By constructing a structure in which the pores are covered with a gas exhaust filter base cloth that also has a gas permeability adjusting function that also functions as a reinforcement, we are constructing a control system that can obtain an arbitrary gas permeation state (velocity, permeation amount). That is, it corresponds to the amount of gas generating agent, bag capacity, etc., and the rough gas permeation state (velocity, permeation amount) is controlled by gas permeation, the size and number of exhaust holes, and the fine control is based on the gas exhaust filter base. A system for controlling the air permeability based on the fabric structure of the cloth has been constructed, and it is possible to easily meet the demand of any gas permeation state.

Since the air bag according to the present invention is designed so that the permeate exhaust of the generated gas is controlled by the exhaust hole provided for the permeate exhaust and the gas exhaust filter covering the exhaust hole, it constitutes the bag body. The air bag component base fabric can be designed with physical properties (strength, storage expandability, heat resistance, etc.) as standard without being limited to other functions such as permeation and exhaust capability, so that it can meet the required physical properties. Cloth setting is extremely easy. Therefore, all of the high-strength grade synthetic fibers produced under the present circumstances are targeted, but when considering the heat resistance imposed on the air bag,
Nylon, polyester, and aramid fibers are preferable, and nylon 66, nylon 46, polyester (polyethylene terephthalate), meta-type or para-type wholly aromatic polyamide, polyparaphenylene sulfonamide, polyparaphenylene sulfide, polyetheretherketone are preferable. , Polyimide, wholly aromatic polyester, and polyetherimide fiber are preferable.

As described above, the base fabric used in the present invention has a low air permeability which is designed to have physical properties (high strength, heat resistance, storage deployability, etc.), and heat resistance. There are two types of gas exhaust filter base fabric designed mainly for air permeability, but the air permeability of the air bag component base fabric is 1.0 cc / cm for the Frazier air permeability measured under a pressure of 124 Pa. ² / sec or less,
The gas exhaust filter base fabric has an air permeability of 1.0 to 35 cc / c of Frazier air permeability measured under a pressure of 124 Pa.
m ² / sec, preferably 2.0 to 20 cc / cm ² /
It is preferably sec. When the Frazier air permeability measured under a pressure of 124 Pa of the gas exhaust filter base fabric is 1.0 cc / cm ² / sec or less, the bottom side air bag constituent base fabric has a level of permeability that does not affect the air bag strength. When an air bag is constructed by perforating air and the size and number of exhaust holes, the exhaust speed of the gas generated from the air bag is insufficient, the internal pressure of the air bag is high, and the impact absorption capacity for passengers is reduced (the impact is large). , 124 Pa
Frazier air permeability measured under the pressure of 35.0cc /
If it is cm ² / sec or more, the filtration of the combustion residue of the gas generating agent will be insufficient, and if the air permeability is extremely large, the exhaust capacity will be excessive, the internal pressure of the air bag will be insufficient, and the impact absorption capacity will be lost, resulting in occupant safety. Cannot be guaranteed.

As the base cloth, a plain weave, a twill weave, a satin weave, and other textured woven fabrics, as well as multiaxial woven fabrics, multiaxial woven fabrics, non-woven fabrics, and the like can be applied, but plain weaves are used from the viewpoint of physical properties, air permeability, and filtration performance.
Twill weave and satin weave are preferably used, and the weave may be performed by selecting the woven structure, the shot density, the constituent fiber denier and the like so as to obtain predetermined physical properties and air permeability. These synthetic fibers are
It is desirable to use a multifilament yarn of 200 denier or more. It should be noted that this air bag constituent base cloth may be coated with chloroprene, chlor-sulfonated olefin rubber, silicone rubber, fluorine rubber, polyvinyl chloride, chlorinated polyolefin, etc. to be used, but it is not against the present invention, but is lightweight. In terms of storability and deployability, the one not coated with the original form of the present invention is superior.

[0016]

The embodiments of the present invention will be described in detail below with reference to specific examples. [Example 1] A plain weave having a warp / weft density of 32 filaments / inch was prepared by using nylon 668 filaments of 840 denier / 140 filaments, and the Frazier air permeability was 0.26.
A highly dense base fabric having a cc / cm ² / sec is obtained. As shown in FIG. 1, a circular cloth having a diameter of 750 mm was punched and cut from this base cloth to obtain a front side (occupant side) airbag-constituting base cloth 1. Next, a cloth of the same shape as that of the base cloth 1 is further punched and cut, a hole 2 having a diameter of 100 mm is punched in the center thereof for attaching an inflator, and a hole having a diameter of 120 mm is further positioned at a position 170 mm from the center by 90 °. Four pieces were punched out so as to form the corners, and a bottom side (handle side) air bag constituent base cloth 4 provided with gas permeation and exhaust holes (vent holes) 3 was obtained.

On the other hand, using nylon 66 filaments of 420 denier / 36 filaments, a plain weave fabric having a warp / weft density of 46 filaments / inch was prepared, and the Frazier air permeability was 4.5.
A highly breathable base cloth of cc / cm ² / sec was obtained, a circular cloth having a diameter of 600 mm was punched out from this base cloth, and a hole 5 having a diameter of 100 mm was punched in the central portion for mounting the inflator. A ring-shaped gas discharge filter base cloth 6 having both reinforcement and reinforcement around the gas discharge hole was obtained. Next, the gas discharge filter base cloth 6 is laminated on the bottom side (handle side) air bag constituent base cloth 4 together with the holes 5 punched for mounting the inflator, and the outer peripheral position of the inflator mounting hole and the gas discharge filter base cloth are laminated. The outer peripheral position of the cloth 6 and the position corresponding to the outer periphery of the vent hole 3 formed in the bottom side (handle side) airbag structure base cloth 4 are sewn with a sewing allowance of 20 mm, respectively, as shown in FIG. The bottom surface side base material 7 was obtained.

Next, the bottom surface side base material 7 is overlaid on the front side (occupant side) air bag constituent base cloth 1 with the side on which the gas exhaust filter base cloth 6 is not laminated facing up, and the outer peripheral portion thereof. Sewing machine sewing S with a seam allowance of 25 mm, Fig. 2
A bag-like material 8 was obtained as shown in (b). Then, from the hole 9 drilled for attaching the inflator of the obtained bag-like object 8, the front side (occupant side) airbag constituent base fabric (a)
The air bag was flipped over and the air bag was turned over. As a result of assembling this air bag into a module and generating explosive gas from the inflator and conducting a field deployment test of the shock absorbing bag, the amount of white smoke leaking from the vent hole and ejected was extremely small, and the area around the inflator mounting part and the vent hole No damage was found around the area.

[Example 2] Using nylon 66 filaments of 420 denier / 72 filaments, a plain weave fabric having a warp / weft density of 55 filaments / inch was prepared and a high density of Frazier air permeability of 0.26 cc / cm ² / sec. Get the base cloth. A circular cloth having a diameter of 750 mm is punched and cut from this base cloth, and the front side (occupant side) air bag constituent base cloth 1
And Next, a cloth of the same shape as that of the base cloth 1 is further punched and cut, and a hole 2 having a diameter of 100 mm is punched in the central portion for attaching an inflator, and further 170 from the center.
Bottom side (handle side) air bag constituent base cloth 4 in which four holes 3 having a diameter of 120 mm are punched out at a position of mm so as to form an angle of 90 ° with each other, and generated gas permeation and exhaust holes (vent holes) are arranged. And

Furthermore, a diameter of 200 m from this same base cloth 4
Three circular m-shaped cloths were punched and cut, and a hole 10 having a diameter of 100 mm was punched out at the center thereof to form an annular inflator mounting portion reinforcing cloth 11. On the other hand, 420 denier / 36 filament nylon 66
A filament weave is used to make a plain weave having a warp / weft density of 46 filaments / inch and a Frazier air permeability of 4.5 cc / cm ² /
A highly breathable base fabric with a sec of 600 is obtained from this base fabric.
mm of circular cloth is punched and cut, and a hole 5 with a diameter of 100 mm is punched in the center of the circular cloth for attaching an inflator, and an annular gas exhaust filter base cloth 6 that also serves as reinforcement for the inflator mounting portion and reinforcement around the gas exhaust hole is formed. Obtained.

Next, the gas discharge filter base cloth 6 is laminated on the bottom side (handle side) air bag constituent base cloth 4 together with the holes 5 punched for mounting the inflator, and further, the inflator is also mounted thereon. The three annular inflator mounting portion reinforcing cloths 11 are overlapped with each other by aligning the positions of the holes 10 drilled for use, and the outer peripheral position of the inflator mounting hole outer peripheral position, the gas exhaust filter base cloth 6, and the inflator mounting portion reinforcing cloth 11 and the bottom side. (Handle side)
The position corresponding to the outer periphery of the vent hole 3 opened in the air bag component base cloth 4 is sewn with a sewing margin of 20 mm.
Then, as shown in FIG. 3, a bottom surface side base material 12 was obtained.

Next, the gas discharge filter base cloth 6 and the inflator mounting portion reinforcing cloth 11 of the bottom surface side base material 13 are formed.
Was laminated on the front side (occupant side) of the airbag-constituting base fabric 1 with the side not laminated, and the outer peripheral portion was sewn with a sewing allowance of 25 mm to obtain a bag-like product 13. Then, the front side (occupant side) airbag-constituting base fabric 1 was grasped and pulled out from the hole 14 of the obtained bag-like material 13 for attaching the inflator, and the bag was inverted to obtain an inside-out airbag. As a result of assembling this air bag into a module and generating explosive gas from the inflator and conducting a field deployment test of the shock absorbing bag, the amount of white smoke leaking from the vent hole and ejected was extremely small, around the inflator mounting part and the vent hole. No damage was found around the area.

[Embodiment 3] The annular gas exhaust filter base fabric 6 in Embodiment 1 is a 3/1 twill weave, and has a warp / weft density of 50.
Book / inch twill weave with Frazier air permeability of 25cc /
When an air bag was made and a deployment test was conducted in the same manner except that the cm ² / sec was changed,
Although the amount of white smoke that leaked from the vent hole was a small amount,
Some damage was found around the vent hole.

[Comparative Example 1] The annular gas exhaust filter base fabric 6 in Example 1 is a 3/1 twill weave and has a warp and weft density of 45.
Book / inch twill weave with Frazier air permeability of 40cc
/ Cm ² / sec The same except that the air bag was created and the same deployment test was performed. As a result, many white smoke was ejected from the vent hole, and tear damage was found around the vent hole. .

[Comparative Example 2] The annular gas exhaust filter base fabric 6 in Example 1 is a plain weave having a warp / weft density of 52 fibers / inch and a Frazier air permeability of 0.7 cc / cm.
^An air bag was created in the same manner except that the rate was changed to ² / sec, and a deployment test was conducted in the same manner. As a result, the amount of white smoke ejected from the vent hole was extremely small, but the bag internal pressure was maintained. It was 1.5 times that of Example 1 and the internal pressure was almost the same as when the vent hole was not provided, and it was observed that the shock absorption to the occupant was not softly received.

The performance evaluation of the products in each example was carried out by the following method. (1) Frazier Air Permeability: The Frazier air permeability under a pressure of 124 Pa was measured according to the JIS-1096 Frazier air permeability measurement method. (2) Inflation test: Using a type 4 inflator manufactured by Morton International Co., Ltd., 90 ° C
A deployment test was conducted on the module kept warm. (3) Filterability: The presence or absence (state) of white smoke ejected outside the bag when the air bag was deployed was visually observed and evaluated.

[0027]

EFFECT OF THE INVENTION Since the air bag of the present invention is constructed as described above, the number of constituent members is small, and the management of the base cloth is easy because the base material is 2 kinds and the number of parts is 3 or 4. Air bag sewing (adhesion) assembly work can be easily performed with high productivity because the number of parts and the number of sewing (adhesion) steps are small. It has a good storage capacity and expandability, and has an appropriate exhaust gas exhaust capacity.
Highly functional, highly functional shock-absorbing air bags with high strength and rich filterability of gas generant combustion residue can be manufactured at low cost.

[Brief description of drawings]

FIG. 1 shows a plan view of an air bag constituent base cloth of an embodiment of the present invention, (a) a plan view of an inflator mounting portion annular reinforcing cloth, (b) a plan view of a gas exhaust filter base cloth,
(C) is a plan view of a handle-side constituent base cloth, and (D) is a plan view of an occupant-side airbag constituent base cloth.

FIG. 2 is a cross-sectional view of a sewn fabric of an airbag-constituting base fabric according to an embodiment of the present invention, in which (a) is a cross-sectional view of a bottom surface side base material,
(B) is a cross-sectional view of a bag-like object.

FIG. 3 is a cross-sectional view of a sewn base fabric for an airbag according to another embodiment of the present invention, in which (a) is a cross-sectional view of a bottom surface side base material and (b) is a cross-sectional view of a bag-like material. is there.

[Explanation of symbols]

 1 Air bag constituent base cloth 2 Inflator mounting hole 3 Vent hole 4 Handle side air bag constituent base cloth 5 Inflator mounting hole 6 Gas exhaust filter base cloth 7 Bottom surface side base material 8 Bag-shaped object 9 Inflator mounting hole 10 Inflator mounting hole 11 Inflator mounting portion annular reinforcing cloth 12 Bottom surface side base material 13 Bag-shaped material

Claims (5)

[Claims] 1. A gas exhaust filter having a handle side air bag component base cloth having at least one gas exhaust hole around the inflator mount hole, and an inflator mounting hole sewn or adhered to the air bag component base cloth. An air bag comprising a base cloth and an occupant-side air bag constituent base cloth sewn or bonded to the air bag constituent base cloth. 2. The gas exhaust filter base cloth is provided with an annular reinforcing cloth for mounting an inflator.
Air bag described in. 3. The air permeability of the air bag-constituting base fabric is 1.0 cc / cm ² / sec or less, and the gas exhaust filter base fabric has a Frazier air permeability of 1.0 to 35.0.
The air bag according to claim 1 or 2, which has a cc / cm ² / sec. 4. A handle side air bag component base cloth having an inflator mounting hole and at least one gas discharging hole formed around the inflator mounting hole, and a gas discharge filter base cloth having the inflator mounting hole and / or The annular reinforcing cloth for attaching the inflator is laminated, sewn or adhered to be integrated, and then the air bag constituent base cloth is sewn or adhered to the passenger side air bag constituent base cloth to form a bag-like material, and the bag-like material is formed. A method for manufacturing an airbag, wherein the occupant-side airbag-constituting base fabric is pulled out from the inflator mounting hole, and the bag-shaped material is inverted. 5. The method for manufacturing an air bag according to claim 4, wherein an annular reinforcing cloth for attaching an inflator is laminated on a gas exhaust filter base cloth, which is sewn or adhered to be integrated.