JP6186216B2 - Airbag belt - Google Patents

Description

  The present invention relates to an airbag that is mounted on a vehicle or the like and protects a passenger's head from an impact such as a collision or rollover. More specifically, the present invention relates to an airbag belt that can prevent a decrease in strength of a belt used for fixing an airbag to a vehicle body.

  As a safety device for protecting an occupant from an impact when a vehicle collides, an airbag device mounted on the vehicle is widely used. In particular, in recent years, in addition to the conventional airbag apparatus for the driver's seat and passenger's seat, a side collision (side collision) airbag apparatus and a rear seat airbag apparatus have been mounted on vehicles.

  For example, the airbag 2 of the airbag device for side collision shown in FIG. 1 has its upper end attached from the front pillar to the roof side rail, and the lower end via an attached bracket 3 (attachment fitting). The belt 1 is attached to the lower part of the front pillar. When an impact is detected, gas flows from the inflator into the airbag and expands. At this time, the presence of the belt 1 allows the airbag 2 to be deployed at a predetermined position.

  Therefore, the belt 1 needs to be strong enough to withstand an impact when the airbag is deployed and the airbag 2 is fixed to the vehicle body at a predetermined position. As a material of the belt 1, it is described in Patent Document 1 that a material that is difficult to stretch, for example, a woven fabric using polyamide yarn or the like is used, and Patent Document 2 is a base fabric formed in a string shape. More specifically, Patent Document 3 describes that a base fabric, that is, a woven fabric, is formed of 66 nylon of 350 dtex and 24.4 / cm (62 / inch). .

  Although none of the above-mentioned patent documents describes a specific form, usually, a plurality of base fabrics as shown in FIG. 5 are stacked (a), or one base fabric is folded from the end. As shown in (b), it is configured to satisfy the required strength during deployment.

However, in the belt formed as shown in FIG. 5, the end 4 (cut surface) of the base fabric is exposed, so that it is easy to cause fraying, and not only the work efficiency at the time of manufacturing the airbag is low, but also the sewing allowance is reduced. Then, there exists a problem that the intensity | strength required for a belt will fall.

JP 2001-122073 A JP 2002-326552 A Japanese Patent Laid-Open No. 2003-054350

  SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems and to provide an airbag belt that has a simple form but prevents a reduction in belt strength and does not reduce the efficiency of manufacturing operations.

That is, the present invention
(1) A belt for fixing an airbag to a vehicle body, wherein a base fabric forming the belt is overlapped with four or more layers so that both ends in the width direction of the belt are located inside Further, the airbag belt is formed by bending a plurality of lines in the width direction of the belt and sewing the vicinity of the center line in the width direction of the belt.
(2) The airbag belt according to (1), wherein the base fabric forming the belt is the same as the base fabric forming the airbag body.

  ADVANTAGE OF THE INVENTION According to this invention, although it is a simple form, the strength reduction of a belt can be prevented and the airbag belt which does not reduce the efficiency of manufacturing operation can be provided.

It is a schematic plan view which shows an example of the form when the airbag using the belt of this invention expand | deploys. It is the model top view which expanded and showed the belt part of this invention. It is a schematic cross section of the belt of the present invention in the AA section of FIG. It is a schematic cross section which shows another form of the belt of this invention in the AA cross section of FIG. It is a schematic cross section of the general belt conventionally used in the AA cross section of FIG.

  The airbag belt according to the present invention is a belt for fixing an airbag to a vehicle body, and is characterized in that a plurality of folds are folded so that an end portion of a base fabric forming the belt is located inside. .

The belt determines the airbag deployment direction when the airbag is deployed, and serves to fix the airbag at a predetermined position after deployment. Therefore, it is necessary to have a strength that can withstand an impact caused by gas inflow from the inflator during deployment and that the airbag is fixed to the vehicle body at a predetermined position. In general, it is said that a tensile strength of 2,500 to 3,500 (N / 12 mm) is required, and it is said that a tensile strength of 3,000 (N / 12 mm) or more is better.

  Since the belt is folded together with the airbag body and accommodated in the vehicle, the belt is also required to be flexible. In order to have the necessary strength for the belt, it increases by increasing the number of overlapping fabrics of the base fabric, but if it is increased too much, the flexibility is impaired and the storage location (space) may be affected, and there is little It is necessary to consider the balance with the required strength at the time of deployment in the number of superimposed sheets.

  With conventional belts, the base fabric is folded several times in a state where the end of the base fabric is visible, or a plurality of base fabrics that have been cut into narrow strips are stacked, mainly near the center line in the width direction. If the edge of the base fabric is frayed, there may be a decrease in the allowance for sewing after sewing, which not only reduces the work efficiency during manufacturing, but also causes fraying after sewing. If it is continuous, the required strength of the airbag belt may be impaired. On the other hand, the airbag belt of the present invention has the end of the base fabric, that is, the cut surface located inside, and exposed to the outside. Therefore, the yarn does not easily flutter from the end of the base fabric, and the strength change is small.

  The folding method for producing the airbag belt of the present invention is not particularly limited, but as shown in the cross section of FIG. It is good to fold along. In this method, the number of overlapping base fabrics is four (four layers) airbag belts. Further, as shown in FIG. 4, there is a method of folding, and the number of overlapping base fabrics may be five (5 layers) airbag belts. The number of sheets to be overlapped can be appropriately determined according to the type and thickness of the yarn used for the base fabric, the structure, the density, the thickness, the strength, and the like.

In general, the number of overlapping base fabrics of airbag belts may be four (four layers) or more. However, in consideration of fraying, six (6 layers) or more is more preferable in terms of strength. In the case of the present invention, since the end portion of the base fabric is folded into the inside of the cross section, the end portion is hardly frayed and the strength of the belt is not easily damaged. Although the number of sheets is not limited, there are cases where the number is 5 or more, which is stronger, depending on the size of the opening (window), the weight of the airbag body, the storage location (space) of the airbag body, and the like.
However, if the number of sheets exceeding eight is overlaid, the burden on the sewing machine needle during sewing becomes large, and workability may deteriorate in sewing. Therefore, the number of overlapping sheets is preferably up to eight.
In addition, it becomes preferable in terms of cost by comprising the said belt using the same base fabric as the base fabric used for an airbag main body.

  The airbag is mainly used for a driver seat of a vehicle, a passenger seat, a side collision and a rear seat, and the airbag belt of the present invention is not particularly limited in use. Useful for side impact airbags.

  Examples of the material of the base fabric used for producing the airbag belt of the present invention include fibers, woven fabrics, knitted fabrics, braided fabrics, nonwoven fabrics, sheet-like materials, net-like materials, or composites and laminates thereof. It is not specified as long as it is a material that satisfies the required performance, and may be the same as or different from the material of the base fabric used for the panels and parts of the airbag body. Then, it can be produced with the remaining base material after cutting, and can be manufactured (produced) at low cost without separately purchasing (preparing separately). Even when these are bonded together, it is preferable to use the same material in that it is easy to select the adhesive used in the airbag body.

  The fabric of the base fabric of the air bag body includes any of a weave weave (basket weave), a lattice weave (ripstop weave), a twill weave, a knit weave, a tangle weave, an imitation weave, a plain weave, or a composite structure thereof. It may be a thing. Of these, plain weave is preferable in terms of the denseness of the woven structure, physical properties, and uniformity of performance. If necessary, in addition to the two axes of warp and weft, a multi-axis design including 60 degrees obliquely may be used, and the arrangement of the threads in this case may be the same as that of the warp or weft. Moreover, you may use the multiple fabric by the loom which mounts a jacquard apparatus.

  What is necessary is just to select the manufacture of the said textile fabric suitably from the various looms used for weaving a normal industrial textile fabric. Examples include shuttle looms, water jet looms, air jet looms, rapier looms, and projectile looms.

  Moreover, the fiber yarn which comprises the said base fabric is not specifically limited, such as a natural fiber, a chemical fiber, and an inorganic fiber. Of these, synthetic fiber filaments are preferred because of their versatility and in terms of fabric manufacturing process, fabric physical properties, and the like. For example, Nylon 6, Nylon 66, Nylon 46, Nylon 610, Nylon 612 and the like, aliphatic polyamide fibers obtained by copolymerization or mixing thereof, nylon 6T, nylon 6I, and aliphatic amine represented by nylon 9T Copolymerized polyamide fiber with aromatic carboxylic acid, polyethylene terephthalate, polytrimethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate alone, polyester fiber obtained by copolymerization or mixing of these, ultra high molecular weight polyolefin fiber, Chlorine-containing fibers such as vinylidene and polyvinyl chloride, fluorine-containing fibers containing polytetrafluoroethylene, polyacetal fibers, polysulfone fibers, polyphenylene sulfide fibers (PPS), polyester Ruetherketone fiber (PEEK), wholly aromatic polyamide fiber, wholly aromatic polyester fiber, polyimide fiber, polyetherimide fiber, polyparaphenylenebenzbisoxazole fiber (PBO), vinylon fiber, acrylic Fiber, cotton, hemp, cellulosic fiber such as kenaf fiber, biodegradable fiber represented by polylactic acid, oxalic acid, silicon carbide fiber, alumina fiber, glass fiber, carbon fiber, steel fiber, etc. As appropriate, one type or two or more types may be selected. Among these, nylon 66 fiber is preferable in terms of physical properties, durability, heat resistance, and the like. From the viewpoint of recycling, polyester fiber or nylon 6 fiber is preferable.

  In order to improve spinnability, workability, durability, etc., these fiber yarns are provided with various commonly used additives such as heat stabilizers, antioxidants, light stabilizers, embrittlement ( Deterioration), lubricant, smoothing agent, pigment, water repellent, oil repellent, concealing agent such as titanium oxide, gloss imparting agent, flame retardant, plasticizer and the like may be used. .

  Although the total fineness of the said fiber yarn is not specifically limited, It is preferable that it is 200-1000 dtex, and it is more preferable that it is 400-800 dtex. If it is smaller than 200 dtex, the strength required of the airbag tends to be difficult to obtain. If it exceeds 1000 dtex, the weight becomes too large, and at the same time, the thickness of the base fabric may increase and the storage property of the airbag body may be deteriorated. is there.

The single yarn fineness is preferably 0.5 to 6.6 dtex. If the single yarn thickness is smaller than 0.5 dtex, the production quality tends to decrease, such as fuzzing, and 6.6 dtex. Beyond this, the base fabric tends to harden.
By reducing the single yarn fineness, the air permeability of the base fabric is reduced, the flexibility is improved, and the folding property of the airbag is improved. Furthermore, the cross-sectional shape of the single yarn may be appropriately selected within a range that does not hinder the manufacturing process of the yarn and the base fabric and the physical properties of the obtained base fabric, such as a circle, an ellipse, a flat shape, a polygon, a hollow, and other irregular shapes. In addition, an air bag having higher pressure resistance can be obtained as the strength of the fiber yarn is higher, but it is preferably 7 cN / dtex, and more preferably 8 cN / dtex or more.

  The base fabric may be either a non-coated base fabric that does not use an air-impermeable material or a coated base fabric that uses an air-impermeable material, and may be selected according to the required airtightness. The air-impermeable material is a material that substantially prevents air from passing through, for example, as described below, and the air-impermeable material is the 8.27.1 A method in JIS L1096 “General Textile Test Method”. In (Fragile method), it means a measured value of 0.0. This material is applied from one side or both sides of the fabric by the method described later. This air-impermeable material may intervene on the surface of the base fabric, the intersecting portion of the yarn bundles constituting the base fabric, or the gap portion of the single fiber yarn.

The amount applied to the coated base fabric using the air-impermeable material is preferably 10 g / m ² or more on one side. Moreover, when it becomes layered, it is preferable that the thickness is 10 micrometers or more. When the applied amount is less than 10 g / m ² on one side or the thickness of the layer is less than 10 μm, it tends to be difficult to obtain necessary airtightness. Further, the upper limit is preferably a small amount within a range in which airtightness can be secured, and may be, for example, 15 g / m ² or a thickness of 15 μm.

  As the air-impermeable material, a material usually used for an air bag base fabric may be used, which satisfies heat resistance, wear resistance, adhesion to the base fabric, flame retardancy, non-adhesiveness, etc. If it is. For example, silicone resin or rubber, polyurethane resin or rubber (including silicone-modified and fluorine-modified), fluorine-based resin or rubber, chlorine-based resin or rubber, polyester-based resin or rubber, polyamide-based resin, epoxy-based resin, vinyl 1 type (s) or 2 or more types, such as a system resin, a urea resin, and a phenol resin, can be used. Of these, silicones or polyurethanes are preferable in terms of adhesion to the base fabric and airtightness.

  The methods for applying to the air-impermeable material are 1) coating method (knife, kiss, reverse, comma, slot die, lip, etc.), 2) dipping method, 3) printing method (screen, roll, rotary, gravure, etc.) ), 4) transfer method (transfer), 5) laminating method, 6) spraying / injecting method, etc., which are not particularly limited. Among them, the range of application amount that can be set (adjustment amount adjustment range) is large. The coating method is preferable.

  Further, in addition to the main material, the air-impermeable material includes various commonly used additives such as a cross-linking agent, an adhesion-imparting agent, a reaction, in order to improve processability, adhesiveness, surface characteristics or durability. Accelerator, reaction retarder, heat stabilizer, antioxidant, light stabilizer, anti-aging agent, lubricant, smoothing agent, anti-adhesive agent, pigment, water repellent, oil repellent, concealing agent such as titanium oxide, gloss You may mix 1 type, or 2 or more types, such as an imparting agent, a flame retardant, and a plasticizer.

  The property of the air-impermeable material as a liquid is a solventless type, a solvent type, a water dispersion type, a water emulsification, depending on the application amount, the application method, the workability and stability of the material, the properties required as a coating material, What is necessary is just to select suitably from a type | mold, a water-soluble type | mold, etc.

  In order to improve the adhesion between the air-impermeable material and the main body base fabric, various pretreatment agents, adhesion improvers, etc. may be added to the air-impermeable treatment agent, or the surface of the base fabric may be preliminarily treated. The pretreatment may be performed. Furthermore, in order to improve the physical properties of the air-impermeable material, or to impart heat resistance, anti-aging properties, oxidation resistance, etc., after applying an air-impermeable treatment agent to the base fabric, drying, crosslinking, vulcanization, etc. , Hot air treatment, pressure heat treatment, high energy treatment (high frequency, electron beam, ultraviolet ray, etc.) may be performed.

Examples Hereinafter, the present invention will be described in more detail with examples. In addition, the evaluation method performed in the Example is shown below.

Tensile strength Based on JIS L 1096, a sample in the form of a belt (string) is used with an autograph AG-50KNIS (manufactured by Shimadzu Corporation) in an environment of room temperature 20 ± 2 ° C. and humidity 65 ± 2%. (Long) A sample (sample) prepared at 20 cm was sandwiched, and a tensile test was performed at a speed of 20 cm / min. The strength at break was measured. The number of the following samples (samples) prepared was 5, and after measuring with N = 5, the average value was calculated.

Draft state and tensile strength of durable belt After grasping both ends in the longitudinal direction of the belt-shaped sample by hand and swallowing 10 times, the state of yarn flaw of the fibers (longitudinal fibers) constituting the belt was visually confirmed. .
○: No flaws can be confirmed at both side edges in the width direction with respect to the longitudinal direction. ×: Judgment based on the ability to confirm flaws at both sides or one side edge in the width direction with respect to the longitudinal direction. After confirming, tensile strength was measured.

Thread tension (uniformity of sewing)
The uniformity of stitches when the belt was sewn was evaluated.
○: Good appearance with uniform seam △: There are rarely uneven seams or thread breakage in about 1 part.
X: It was judged that the stitch interval was remarkably uneven, or a plurality of thread breaks were heard and the appearance was very bad (the thread tension was bad).
When the thread tension is poor, the thread is loose and the sewing part is easy to open.

Example 1
Both warp and weft are 470 dtex / 72f of nylon 66 fiber (yarn strength 8.5 cN / dtex, single yarn fineness 6.5 dtex), and the weft density of both warp and weft is 51 / 2.54 cm. A woven fabric was prepared, and a solventless heat-curing silicone rubber coating material (resin physical properties of 4.0 MPa or more and elongation of 130% or more in accordance with JIS K 6249) was applied to one side of this plain woven fabric at a coating amount of 25 g / m. ² (weight after drying) and heat-treated to obtain a coated base fabric (woven fabric).
After the base fabric (woven fabric) is cut (cut) to a width of 60 mm and a length of 400 mm, it is folded into a four-ply stack as shown in FIG. 3 to form a string, and the center of the width is sewn in a linear shape to a width of 12 mm, A belt of the present invention having a length of 400 mm was produced. The evaluation results are shown in Table 1.

Example 2
Using the coated base fabric (woven fabric) obtained in Example 1, cut into a width of 75 mm and a length of 400 mm, folded into a five-layer stack as shown in FIG. A belt having a width of 12 mm and a length of 400 mm was produced. The evaluation results are shown in Table 1.

Comparative Example 1
Using the base fabric obtained in Example 1, four base fabrics having a width of 12 mm were overlapped as shown in FIG. 5A to produce a belt having a width of 12 mm and a length of 400 mm and evaluated. The evaluation results are shown in Table 1.

Comparative Example 2
A belt having a width of 12 mm and a length of 400 mm was prepared by using the base fabric obtained in Example 1 and superposing four sheets of the base fabric of FIG. And evaluated. The evaluation results are shown in Table 1.

Comparative Example 3
Using the base fabric obtained in Example 1, the base fabric was folded as shown in FIG. 5 (b), and a four-layer belt having a width of 12 mm and a length of 400 mm was prepared and evaluated. The evaluation results are shown in Table 1.

Comparative Example 4
Nylon 66 470 dtex / 72f (yarn strength 8.5 cN / dtex, single yarn fineness 6.5 dtex) for the warp yarn, Nylon 66 235 dtex / 72f (yarn strength 8.5 cN / dtex, single yarn fineness 3.2 dtex) for the weft yarn Using this, a belt having a width of 12 mm webbed with a double weave was produced and evaluated. The evaluation results are shown in Table 1.

The belt of the present invention and the comparative example 4 of the conventionally used belt are inferior in terms of tensile strength and the like, but the present invention is used in the airbag body remaining after the airbag body is manufactured. Since a belt is made of a base fabric that cannot be used, a new woven fabric is not prepared (purchased or manufactured), and a belt can be obtained at a low cost, which is excellent in terms of cost and environment. .
In addition, Comparative Examples 1 and 3 in which four sheets are stacked and Comparative Example 2 in which six sheets are stacked satisfy the initial strength that is said to be necessary, but the strength is not maintained when a fray occurs, and the results are not very interesting. became.

1 Belt 2 Airbag 3 Bracket 4 Base fabric edge

Claims (3)

A belt for fixing an airbag to a vehicle body,
The base fabric forming the belt is folded in a plurality of directions in the width direction of the belt so that both end portions in the width direction of the belt are located inside and overlaps with four or more layers. A belt for airbags that is sewn near the center line in the direction . The airbag belt according to claim 1, wherein the base fabric forming the belt is the same as the base fabric forming the airbag body. Side impact air bag comprising airbag belt according to any one of claims 1-2.

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