JPH03227751A - Air bag - Google Patents

Abstract

PURPOSE:To obtain a seamless and light air bag with dynamical characteristic to withstand impact at the time of expansion by winding continuous threads and yarns to form the air bag by a nonwoven fiber bag body integrally formed into a three-dimensional structure. CONSTITUTION:An air bag is formed by winding continuous threads and yarns and forming a nonwoven fiber bag body integrally formed into a three- dimensional structure. In this case, the threads and yarns are continuously supplied and wound around the outer circumferential surface of a core body so as to vary the threads and yarns supplying positions continuously vary to form a three-dimensional or bag like three-dimensional surface body. Further, in order to give air-shielding property, heat resistance, fire retardance, etc., to the air bag and improve these properties, elastomers are mixed with the three dimensional surface body formed on the outer spherical surface of the core body. A seamless, light and compact air bag which is easy to fold and store, and can withstand impact at the time of expansion, can thus be obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to airbags. More specifically, the present invention relates to an airbag that has no seams, is lightweight, and has mechanical properties that can withstand impact when deployed.

[Background Art] In recent years, air bag systems have been put into practical use as safety devices for protecting occupants of various transportation systems, especially automobiles.

Usually, airbags are coated with an elastomer such as sulfur-containing rubber or laminated on the surface to improve heat resistance, flame retardance, air shielding properties, etc., as shown in JP-A No. 49-47692. It is made by cutting and sewing the base fabric.

In addition, the part where the gas generator or inflator for deploying the air bag is attached (hereinafter referred to as the "attachment"), and the gas exhaust hole that absorbs the energy when the occupant hits the deployed air bag, are as described above. It is created by punching out a circular shape from a portion of the cut base fabric.

However, when the airbag is actually activated, the reaction of the gas generating agent inside the inflator occurs in an extremely short period of time. Not only is the force applied, but when the airbag is expanded from its folded state, the high-temperature gas generated within the inflation flake can melt the seams in the seams or cause them to become unevenly tensioned. As a result, the air bag passes through small openings, such as thread holes, in a concentrated manner, causing displacement of the seam and destruction of the base fabric constituting the bag, significantly impairing the air bag's expansion function.

As mentioned above, the seamed part and punched part of the airbag are
It can be said that this is a factor that significantly reduces the mechanical properties when the airbag is deployed.

Therefore, the mechanical strength of the airbag can be improved by sewing multiple layers of seams, reinforcing several pieces of cloth around the opening of the punched part, especially when mounting it to support the impact force during expansion. There are ways to improve it. However, all of the above measures have the disadvantage that not only the processing steps are complicated, but also a large amount of materials are used, which increases the weight of the product.

[Problem to be solved by the invention]

The object of the present invention is to have no sutures, be lightweight, and not bulky.
It is an object of the present invention to provide an airbag that is easy to fold and store, and has mechanical properties that can withstand impact when expanded.

[Means to solve the problem]

The present invention is a seamless airbag made of a non-woven fiber bag whose three-dimensional horizontal structure is integrally formed by winding continuous thread.

The three-dimensional planar body used in the airbag of the present invention is obtained by continuously supplying fiber threads onto the outer circumferential surface of a core body and winding the fiber threads so that the supply positions on the surface are successively different. This three-dimensional planar body requires continuous yarn winding to achieve impact resistance and light weight. This three-dimensional planar body is a state in which fiber threads draw a trajectory with continuous and regular shifts in phase, and the fiber threads, which are responsible for the mechanical properties of the airbag, are cut and separated in all directions around the bag. Therefore, the physical properties of the fiber yarn can be utilized extremely effectively.

The airbag of the present invention is composed of the three-dimensional planar body and an elastomer. The three-dimensional planar body can be produced by a method such as rotating the core itself that rotates and moves the supplied fiber thread by an external force, a support shaft, etc., or by using the above two methods in combination.

In addition, in order to function as an airbag, the three-dimensional planar body must be three-dimensional, that is, bag-shaped, and for this purpose, it is important to wrap the fiber threads around the outer peripheral surface of the core body. .

The core used in the present invention may have a shape that is almost similar to the outer shape of the final airbag, such as a sphere, a long ellipse like a rugby ball, a disk, a pillow, a rectangular parallelepiped, a cube, etc. , it may be made into any desired shape.

Further, the core may be made of a split type such as metal, plastic, or wood, or may be made of a thin layered material such as rubber, film, or elastic sheet that is expanded under pressure.

When supplying and winding the fiber threads onto the outer peripheral surface of the core, a resin with excellent adhesiveness and fixing properties is applied to improve the adhesion between the threads and prevent them from slipping during wrapping. You can. The resin may be in any state such as a solution, paste, or powder, and can be fixed by drying, heating, or melting while winding the resin.

Furthermore, in order to create openings such as an opening and an exhaust hole for attaching an inflator to an airbag, a convex projection or the like may be provided on a part of the core body.

The types of fiber yarns constituting the airbag of the present invention include long fibers obtained by melt spinning, dry spinning, wet spinning, etc., spun yarns obtained from short fibers, a combination thereof, and bulk processed yarns. Any processed yarn that has been subjected to such processes may be used. Further, the thickness may be selected depending on the purpose. Further, the fiber yarn may be a ribbon, a tape, a braid, or the like, which has been made into a collection of thin strips in advance. Alternatively, it may be cut out or splinted from a film.

Materials for the airbag fiber yarn of the present invention include, for example, boria and mid fibers such as nylon 6.66.46; aramid fibers such as copolymers with paraphenylene terephthalamide and aromatic ether; polyalkylene fibers; Polyester fibers represented by terephthalate; wholly aromatic polyester fibers; vinylon fibers; rayon fibers; polyolefin fibers such as ultra-high molecular weight polyethylene; polyoxymethylene fibers; sulfone fibers such as phenylene sulfon and borisulfon; polyether ether ketone Fiber; polyimide fiber; polyetherimide fiber; carbon fiber, but in some cases, glass fiber,
Inorganic fibers such as ceramic fibers and metal fibers may be used alone or in combination.

The material for the fiber yarn may contain various additives that are commonly used to improve productivity or properties in the manufacturing process or processing process of the raw yarn.

For example, it may contain a heat stabilizer, an antioxidant, a light stabilizer, a smoothing agent, a plasticizer, a thickener, a pigment, a brightening agent, a flame retardant, and the like.

Further, in order to improve processing characteristics in subsequent steps such as winding around a core and coating with an elastomer, heating, gluing, resin processing, etc. may be performed.

In the three-dimensional planar body used in the present invention, the amount and density of the fiber threads wrapped around the core may be selected depending on the desired characteristics of the airbag. For example, the amount of wrapping is 50 to 300g/
The range of rd is preferred but not limited.

The elastomer used in the present invention is essential for imparting and improving the air shielding properties, heat resistance, and flame retardance of the airbag. It is possible to obtain a lightweight airbag with excellent impact resistance, which is the object of the invention.

The elastomer used in the present invention may be one that satisfies the performance required for airbags, such as halogen-containing rubbers such as EVA, fluororubber, chloroprene rubber, Hypalon rubber, and epichlorohydrin rubber; vinyl chloride, vinylidene chloride, and chlorinated rubber. polyolefin, vinyl fluoride,
Examples include, but are not limited to, halogen-containing resins such as vinylidene fluoride; polyurethane rubbers and resins; silicone rubbers and resins; silicone fluoride rubbers and resins; and mixtures of two or more thereof.

These elastomers have reinforcing agents such as carbon, anti-aging agents, which are commonly used to improve their properties.
It may contain various additives such as a vulcanizing agent, a vulcanization accelerator, a vulcanization retarder, a lubricant, a plasticizer, an antioxidant, a heat stabilizer, a flame retardant, and a pigment.

A composite of an elastomer and a planar body is produced by coating, scattering, spraying, or immersing a polymer solution such as a solvent solution or an aqueous dispersion in a state in which fiber threads are wound around the outer peripheral surface of the core body. This is done by drying, heat treating, and removing the core. In some cases, the core itself is made of a thin film such as an elastomer sheet or film, and fiber threads are wrapped around it under pressure, without the need to remove it from the product.
It can also be used as a composite as the innermost airtight layer of a product.

The amount of elastomer to be used may be selected depending on the required air shielding properties, flame retardance, etc., but for example, 5 to 50 g.
/rr? Although the degree is preferable, it is not limited to this.

〔Example〕

The present invention will be explained below with reference to Examples. In addition, performance evaluation of the airbag in the example was performed by the following measurement method.

1) Capacity Submerge the airbag in a water tank, inject water into the interior through the mouth, and determine the amount of water injected at 500IIff1 of the water column and use it as the bag capacity.

2) Weight Measured using the electronic top material shown above.

3) Bursting strength The burst test device shown in Figure 3 was used to test the airbag (balloon (8), which has a larger capacity when inflated than the force).
), and then fix the airbag to the plate (9) using the mounting tool 0ω. High pressure air (
While adjusting the supply amount of step 6), inflate the air bag (7) together with the rubber balloon, and measure the pressure when the air bag bursts using the pressure gauge 02).

Example 1 A metal disc-shaped core having an outer diameter of 65 cm and a center thickness of 1Oc+i, which can be divided into 24 parts, as shown in FIGS. 2 and 3, was assembled. On the outer surface of one panel, a convex cylinder corresponding to a 10 cm diameter inflation hole and a 3 cm diameter exhaust hole (a pair) was provided.

While slowly rotating this core around a support rod, six parallel yarns of nylon 66210' were wound around the outer peripheral surface of the core while moving the supply position while adhering the urethane resin to the surface.

After winding, the fiber yarn was dried in a hot air dryer at about 100°C, and then chloroprene latex was spray applied. The core removed from the support is heated at 120°CX5.
After heat treatment for a minute, the core was disassembled and the attachment was removed from the mouth.

An airbag with a capacity of 622 was obtained, consisting of a sheet of nylon 66 fibers and chloroprene latex.

The characteristics of the airbag are shown in Table 1. It is lightweight and has excellent burst resistance.

Example 2 As shown in FIG.
Installing a silicone rubber balloon with a convex part is approximately 25 mm in diameter.
Inflated to a size of cm. The balloon was slowly rotated around the support rod, and the four parallel yarns of nylon 66 fibers 210' were uniformly wound around the entire spherical surface while applying a silicone adhesive.

After winding, the balloon was heat-treated for about 130"CX10 minutes, and then the balloon was removed from the support rod by reducing the pressure, and the balloon was cut off without damaging either the pair of protrusions or the fiber threads.

A capacity 631 air bag was obtained consisting of a sheet of nylon 66 fibers and silicone rubber. The characteristics of the airbag are shown in Table 1. It is lightweight and has excellent burst resistance.

Comparative Example 1 Nylon 66 fiber plain weave (210', weave density 65X
Bog/rd (solid content equivalent) of a toluene solution containing 35% chloroprene rubber was applied to one side of the
It was dried for 10 minutes at 160°C and then heat treated at 160°C for 20 minutes.

Two circular pieces of cloth (diameter 76cm) were made from the obtained coated cloth.
a+) was cut. One of the circular pieces of cloth has an inflator with a diameter of 10cm.A pair of exhaust holes with a diameter of 3C is installed at the opening, and the rubber-coated surfaces are aligned with the other side. A bag with an outer diameter of 71 cm was created by sewing the periphery using thread).

The airbag was attached to the mouth by sewing two layers of the same coated base fabric as the airbag.

The properties of the obtained bag are shown in Table 1. The airbag of Comparative Example 1 is not only heavier but also has poorer burst resistance than the airbag of Example 1.2, which has approximately the same capacity.

Table 1 [Effects of the Invention] The airbag according to the present invention is extremely light compared to conventional ones, is not bulky, can be easily folded and stored, and has excellent mechanical properties when the bag is expanded.

The present invention is extremely superior in that it enhances the reliability of the airbag and enables rapid deployment of the airbag system as a safety device for protecting occupants.

[Brief explanation of drawings]

FIG. 1 is a plan view of an example of a three-dimensional planar body in the process of being manufactured, in which fiber threads are wound, as seen from the upper side as in FIG. 2. Figures 2 and 3 are diagrams for explaining the core body for creating the three-dimensional planar body used in the airbag of the present invention. Figure 2 is a schematic longitudinal cross-sectional view, and Figure 3 is a plan view from above. It is a schematic diagram. FIG. 4 shows the air vane of the present invention in Example 2. l...Support, 2...Attachment is at the eye part,
3...Exhaust hole part, 4...Outer surface of the core, 5...1 piece divided into 24 parts of the core, 6...
...High pressure air, 7... Air bag, 8...
... Balloon, 9 ... Air bag mounting plate, 10
...... Fixture, 11... High pressure air introduction pipe, 12... Pressure gauge, 13... Pressure adjustment valve.

Claims (1)

[Claims] A seamless airbag made of a non-woven fiber bag whose three-dimensional horizontal structure is integrally formed by winding continuous yarn.