JP2000062563A - Side air bag - Google Patents

Abstract

PROBLEM TO BE SOLVED: To simply provide a side bag to be provided with both the functions of breast protection and head protection, be robust and excellent in a develop ment shape and initial developing ability. SOLUTION: At a boundary part between the breast protection part and the head protection part of an air bag, at least parts (, for example, 15b and 15d in a Fig) of a sewn part between air bag base cloths, except an outer periphery, are intercoupled at intervals of a distance of 3-100 mm by a sewing thread not broken during development. Further effectiveness is provided by using a heat resistant material as a sewing thread.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a vehicle collision,
The present invention relates to an airbag for protecting an occupant, and particularly to a side airbag, which provides a robust bag easily.

[0002]

2. Description of the Related Art In recent years, an airbag system has become widespread as a safety device for protecting an occupant, and the number of wearing parts has increased, such as from a driver's seat to a passenger's seat, a side collision protection, and a rear seat.

[0003] In particular, an airbag for protecting an occupant from a side collision, that is, an airbag for side collision protection (hereinafter referred to as a side bag), has been attracting attention as a means for further enhancing safety for an occupant.

However, since the side bag is deployed in a narrow space between the occupant seat and the vehicle body, it is necessary to protect the occupant with a bag having a small shape and a small capacity. It is necessary not to give. In addition, since the distance between the door and the occupant is small when a collision occurs, it is necessary to inflate the bag in an extremely short time. Especially, first of all, the chest protection to reduce the impact on the occupant's chest. It was required to prioritize the development of the department.

Therefore, a belt-like body, which is provided on the driver's seat bag or the passenger seat bag and corresponds to a hanging string for controlling the bag deployment shape, is indispensable. For example, in Japanese Unexamined Patent Publication No. 6-227348, a connecting portion having a ventilation hole is provided at the boundary between the chest bag and the head bag, and a hanging strap called a tether is provided on the head bag. It has been proposed that the bag be unfolded, then the head bag be unfolded, and the tether control the shape of the head bag. However, the side bag has a smaller shape and a smaller capacity than a driver's seat bag and the like, and the work of providing these connecting parts and hanging strings in the bag is extremely complicated.

On the other hand, Japanese Patent Application Laid-Open No. 9-39710 discloses that
A method of intermittently stitching the middle part of the chest bag and the head bag and ventilating hot gas from the inflator from the non-sewn part is also proposed, but in this case, the bag can be easily manufactured. Since the deformation of the non-sewn portion due to the bulge is remarkable and an extremely large impact force is generated in the stitched portion, it is necessary to repeatedly stitch the end of the stitched portion to reinforce it. Further, since the stitches are intermittently sewn, only one stitching portion can be sewn by one sewing operation. Therefore, it is necessary to perform sewing work for each stitching part,
The work of intermittently stitching the stitched portions together was extremely complicated.

[0007]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a side bag which is easy to sew and is robust while maintaining the same deployability as a conventional side bag.

[0008]

Means for Solving the Problems As a result of the inventor of the present invention, as a result of earnest efforts regarding the structure and sewing technique of a bag for realizing initial deployment performance and robustness suitable for a side bag having a small shape and a small capacity, I was able to solve the problem.

That is, the present invention relates to (1) an airbag for side impact protection, which is constructed by stitching members together and is mounted to protect the occupant's chest and head. At the boundary between the chest protection portion and the head protection portion, at least a part of the stitching portion between the airbag body base fabrics except the outer peripheral portion is 3 to 100 mm by a sewing thread that does not break during deployment.
Side airbags, which are connected to each other with a space between them, (2) The connecting portion further includes a chest protection portion and / or a head protection portion of the airbag. (3) The melting point or decomposition point higher than the melting point or decomposition point of the fiber material constituting the airbag body base cloth, A side airbag according to the above (1) or (2), characterized by comprising a heat-resistant fiber yarn having (4), wherein the sewing thread is provided with heat resistance by a heat-resistant material. The side airbag according to any one of (1) to (3), (5) the connecting portion is sewn by continuous stitching or intermittent stitching, (1) to (4) The side airbag according to any one of the above.

The side airbag according to the present invention has a structure in which airbag body base fabrics are removed except for the outer peripheral portion of the boundary between the chest protection portion and the head protection portion in order to obtain an appropriate airbag deployment shape and deployment performance. At least a part of the sutured part of 3-10
It is important to connect them with an interval of 0 mm, preferably 5 to 80 mm. Furthermore, in addition to the boundary portion, by forming the connecting portion also on the chest protection portion and / or the head protection portion, it is possible to control the shape of the bag that restricts the excessive inflation of the airbag.

The interval between the connecting portions is a chest protection portion and / or an alternative to the suspension string for controlling the bulge when the airbag is deployed.
Alternatively, at least a part of the sewn portions of the airbag body base fabrics except for the outer peripheral portion of the head protection portion may be connected to each other with a space of 20 to 100 mm, preferably 40 to 80 mm.

Further, in order to ensure the initial deployment of the chest protection part, the gas flow from the inflator directly communicates with at least a part of the seam at the boundary between the chest protection part and the head protection part. So that the spacing is narrower than that of the part to replace the sling string, that is, 3 to 30 mm, preferably 5 to 20 m
They may be connected to each other with a space of m.

The sewing thread used for connecting the base fabrics of a specific portion except the outer periphery of the airbag main body fabric with a constant interval is used as the sewing thread number which is usually used for stitching an airbag, for example, 5 Count yarn, 8 count yarn, in some cases,
A thicker thread or a thinner thread may be used at a normal number of needle movements of 2 to 6 needles / cm.

Further, since the sewing threads interconnecting the airbag body base fabrics are exposed to the hot gas from the inflator when the airbag is deployed, the melting point or the decomposition of the fiber material constituting the airbag body base fabric is decomposed. Using a heat-resistant fiber yarn having a melting point or decomposition point higher than the point,
Further, the effects of the present invention can be effectively exhibited.

That is, usually, the fiber material constituting the airbag body base cloth is often a material having a melting point of about 260 ° C. such as nylon 66 and polyester, and has a higher melting point or decomposition point than these materials. Fiber materials having, for example, polyphenylene sulfide fiber, polyether ether ketone fiber, polytetrafluoroethylene fiber, polyethylene naphthalate fiber, polyarylate fiber, aramid fiber, nylon 46 fiber, carbon fiber, alumina fiber, silicone carbide fiber, steel One or more filaments such as fibers, spun yarn, mixed yarn, mixed yarn, mixed twisted yarn, wound yarn and the like may be used, but the present invention is not limited thereto. Furthermore, a method such as 1) coating a heat-resistant resin or paint on a sewing thread that is usually used for sewing airbags, and 2) compounding the heat-resistant fiber may be used. For example, the heat-resistant resin includes, but is not limited to, silicone-based resin or rubber, fluorine-based resin or rubber, epoxy-based resin, phenol-based resin, and polyimide-based resin. Further, the heat resistant fiber and a normal sewing thread may be combined by winding, interlacing or the like. Further, a material to which a resin, an oil agent, a wax or the like which is generally used for improving sewability is applied may be used.

In the side bag of the present invention, at least a part of the sewn portions between the main body base cloths at specific portions except the outer periphery of the airbag has a constant interval in order to regulate the swelling of the bag at the time of deployment and the initial deployability. Although they are connected to each other while being kept, the connection can be made by a method such as 1) a binding stitch method, 2) a lock stitch thread loosening method, but is not limited thereto.

For the stitching of the connecting portion, for example, a continuous stitch or a staggered stitch, a castle stitch, a loop stitch, a wavy stitch or the like may be appropriately selected by a lock stitch, or a combination thereof may be appropriately selected. Either one or a plurality may be used.
Also, in order to prevent the sewing thread used to sew the connecting part from being damaged by the shock at the time of unfolding, the connecting part of the main body base cloth is the same base cloth as the main body base cloth or a separately prepared reinforcing base. You may apply cloth etc. and connect.

In order to prevent the sewing thread used for the connecting portion from sliding during the deployment of the air bag to change the distance between the two main body base fabrics of the connecting portion, the sewing thread is first connected and then the adhesive, The thread of the connecting portion may be fixed to the base cloth by applying a rubber paste, an adhesive, a resin liquid, or the like, or by applying a patch cloth or tape applied with the various substances in advance.

The spacing between the base fabrics of the connecting portion may be the same over the entire stitched portion or may be partially varied, and can be selected according to the required control shape of the airbag and the initial deployability. Good.

Since the storage space of the side airbag is small, it is possible to further enhance the effect of the present invention by thinning the raw yarn used for the base fabric of the airbag body and lightly folding the airbag to reduce the capacity. Is effective in.

That is, a yarn that is thinner than 840 denier, 420 denier, or 315 denier that has been conventionally used as a base fabric of an air bag, for example, 200
By using a woven fabric having a denier or less and a basis weight of 150 g / m ² or less, the folding volume of the airbag is reduced, and the structure of the seat for accommodating the airbag can be simplified. The side airbag of the present invention is preferably mounted on the seat, but may be mounted on the vehicle body side.

In this case, since the base cloth may be damaged by the same sewing method as the conventional one, not only the sewn portion between the airbag main body base cloths at a specific portion in the present invention, but also the main body base cloth outer peripheral portion, It is advisable to sew a sewn portion such as a reinforcing cloth attachment portion for attaching an inflator under the sewing conditions specified by the following formula and a thread count T satisfying the formula and the number of stitches S (needle / cm).

20≤T≤60 2 ≦ T / S ≦ 8 The sewing conditions will be described below.

In the conventional single yarn constituting the original yarn of 315 denier or more, the single yarn denier is 3 denier or more, and 1
Book, one thread is relatively thick, while 200
A single thread of a denier or less original thread is often a thin thread of 2 denier or less. When sewing with a thick sewing thread count and a corresponding thick sewing needle, the single thread is damaged by the tip of the sewing needle, The penetration of the thick thread count tends to force the fabric to form large stitch holes.

As a preferred measure of the present invention, when a thin fabric having a basis weight of 200 g or less and a basis weight of 150 g / m ² or less is used as the airbag body base fabric, it is used for sewing the body fabric base. Set the sewing thread count T of the sewing thread to 20.
It is desirable that the range is ≦ T ≦ 60, preferably 20 ≦ T ≦ 50. With a count smaller than 20 count, that is, a thick sewing thread, a large stitch hole is formed in the fabric,
When the number of stitches is larger than 60, that is, when the sewing thread is thin, the effect of reinforcing the sewn portion is small. The sewing thread count here is
JIS L-2510, L-2511, and L-251
The number of the sewing thread called the synthetic fiber sewing thread specified in 2 is shown, and in the case of the filament thread sewing thread, the relationship between the number and the denier is
The outline is as follows: 20th is 600-720 denier, 30th is 400-480 denier, 40th is 270-330 denier, 50th is 200-240.
Denier and 60th are 140-170 denier.
In the case of spun yarn, it may be converted from the decitex in the numerical table described in each JIS.

Further, the proper number of stitches S for the thread count T
By using (needle / cm), the optimum stitch strength can be obtained. That is, 2 ≦ T / S ≦ 8, preferably 3
Number of stitches S for sewing thread count T so that ≦ T / S ≦ 7
It is desirable to specify (needle / cm).

If T / S is less than 2, the stitches become dense,
Not only is the sewn part rough and hard, but the man-hours for sewing also increase. On the other hand, if T / S is larger than 8, the seams become too coarse and it is impossible to secure an appropriate seam strength.
The sewing machine needle used for sewing according to the present invention is 20 times thicker than the thick needle having a needle number of 20 or more, which is used in a conventional airbag.
It is advisable to use a fine sewing needle having a count less than or equal to the count, for example, 18 count or 16 count. Further, it is more effective to use a sewing machine needle having a rounded tip end called a ball point type.

When the sewing thread to be used is an upper thread, a lower thread or the like, it is desirable that all the sewing threads satisfy the relational expressions and the relations of the present invention. Only one of them may satisfy the formula and the relation of the formula.

The side airbag according to the present invention is a side bag for protecting a vehicle from a side impact, and is stored in a folded state in a seat bag portion of an occupant, and a side on which a high load acts on the airbag bag body. By the gas ejected from the inflator at the time of the collision, the side windows and the occupant's head,
The airbag is a side impact protection airbag that is deployed in the space between the chests, and can be applied to an airbag having a structure for arranging these airbags. The airbag may have any shape as long as it can protect the occupant's chest and head at the same time, and may have a quadrangular shape, an oval shape, an L shape, an inverted L shape, or a modified combination thereof. In addition, in the present specification, the chest means the abdomen.

The fabric constituting the airbag of the present invention may be subjected to impermeable processing by laminating rubber or resin in a laminated manner, depending on the performance of the inflator, the capacity of the airbag, the site of use, etc. A non-coated woven fabric that is not processed to be impermeable may be used. In the case of an uncoated fabric, scouring, drying, heat setting, etc. may be carried out, and conditions such as heat setting temperature may be selected in consideration of air permeability, mechanical properties and the like. Further, the fiber yarns constituting this woven fabric are not particularly limited, and examples thereof include nylon 6, nylon 66, nylon 46, nylon 610, etc., or a polyamide fiber or polyethylene obtained by copolymerization or mixing thereof. Terephthalate, polybutylene terephthalate,
Alone of polyethylene naphthalate or the like, or copolymerization thereof, polyester fiber obtained by mixing, paraphenylene terephthalamide, and aramid fiber typified by a copolymer of this and aromatic ether, wholly aromatic polyester fiber, Vinylon fiber, polyolefin fiber such as ultra high molecular weight polyethylene, vinyl chloride type and vinylidene chloride type fiber, fluorine type fiber including polytetrafluoroethylene type, polysulfone (PS) fiber, polyphenylene sulfide type fiber (PPS), polyether ether ketone From PEEK fiber, polyimide fiber, polyetherimide fiber, cellulosic fiber including high-strength rayon, acrylic fiber, carbon fiber, glass fiber, silicone carbide (SiC) fiber, alumina fiber, etc. May be constant, but, in some cases,
Inorganic fibers such as metal fibers represented by steel may be included.

In these fiber yarns, various additives usually used for improving the spinnability, processability, and durability of the material, such as heat stabilizer, antioxidant, light stabilizer,
Anti-aging agent, lubricant, smoothing agent, pigment, water repellent, oil repellent,
One or more kinds of hiding agents such as titanium oxide, gloss imparting agents, flame retardants, plasticizers and the like may be used. Further, depending on the case, twisting, bulkiness processing, crimping processing, winding processing and the like may be performed.

Further, the yarn is not particularly limited to filaments of long fibers, spun yarns of short fibers, composite yarns of these, and the like.

[0033]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described more specifically with reference to Examples. In the examples, the performance evaluation of the airbag was performed by the following method.

(1) Inflated state The inflator insertion part of the bag is partially sewn, pressurized air is injected into the bag in a sealed state except the pressurized air supply part, and the bag inner pressure is set to 100 kpa. I observed the deployment situation of.

(2) Folding thickness The bag is folded three times from the head protection portion toward the inflator insertion opening, and is bent and bent once toward the chest protection portion. The acrylic resin is about 5 mm thick. It was sandwiched between the plates, a load of 1 kg was placed on the resin plates, and after 1 minute, the distance between the resin plates was measured. The measured value is 10 in the case of Comparative Example 1.
The relative comparison value was set to 0.

Example 1 Nylon 66 fiber 420 was used as the base fabric for the airbag body.
A non-coated plain woven fabric using d / 70f (original yarn strength of 9.2 g / d) with a warp density of 55 yarns / inch for each weft was prepared. Then, two pieces of base fabric having the shape shown in FIG. 1 were cut. The dimensions of each part in FIG. 1 are A = 300 mm and B =
100 mm, C = 250 mm, D = 270 mm, E = 3
It was 50 mm, F = 800 mm, and G = 450 mm.
Two base fabrics were overlapped and the outer circumference was sewn with a seam allowance of 20 mm (6a, 6b). The upper thread and the lower thread were both nylon 66 fiber, 5th count thread, and were sewn in two rows with a double chain stitch at a needle movement rate of 3.5 needles / cm. Then, as sutures for replacing the hanging string of the airbag, the base cloth 9 is formed in two straight lines such as 4a and 4b.
Sewing was performed with a lock stitch sewing machine equipped with a thread loosening device so that the distance between a and 9b was 60 mm. Incidentally, such a sewing machine is commercially available, and it performs an operation of inserting a nail into one needle and one needle of an upper thread and hooking the needle to loosen the thread. As the sewing thread, both the upper thread and the lower thread were connected with a number of hand movements of 2 needles / cm by a No. 5 yarn of aramid fiber (Kevlar, manufactured by DuPont Toray).

Further, a suture line 5 was provided at the boundary between the chest protection portion and the head protection portion as a gas flow rate control member for the head protection portion. Using a lockstitch sewing machine equipped with a thread loosening device, base cloth 9
Suture lines 4a, 4 so that the distance between a and 9b is 5 mm.
The same sewing thread as that of b was used, and the needles were connected at 2.5 needles / cm.

The side bag according to the present invention can be manufactured very easily, and controls the gas flow to the head protection part,
Moreover, a developed shape was obtained.

Example 2 Nylon 66 fiber 140d / 68f as the base fabric for the main body
A non-coated plain woven fabric having a yarn density of 92 yarns / inch was prepared using (original yarn strength of 8.2 g / d). As shown in FIG. 2, two cut pieces having a size according to Example 1 were sampled and used as reinforcing cloths in the stitched portions 14 and 15 of the respective base cloths in the main body cloth in Example 1. The same base cloth as the one was sewn. For sewing, both needle thread and bobbin thread were made of nylon 66 fiber, 20 count thread, and the number of stitches was 4.
5 stitches / cm, lock stitching was performed. Then, the two base fabrics were overlapped and the outer periphery was sewn. For stitching, a nylon 66 fiber, 20 count yarn is used as the sewing thread, and the number of needles moved is 5.5 needles / cm.
Double chain stitching (two rows) was performed. Next, the sutured portions 14 and 15 were connected using a lock stitch sewing machine with a thread loosening device. Using aramid fiber (Nomex, manufactured by Toray-Dupont Co., Ltd.) No. 20 yarn, (1) the stitching portion 14 has a zigzag stitch (folding angle 90 °, swing width 20 m) as shown in FIG.
m), the number of stitches moved is 2.5 needles / cm, the distance between the base fabrics 19a and 19b is 60 mm, and (2) the suture portion 15
Is the base cloth 19a, 19c for the portions 15a, 15c, 15e.
b closely, 15b, 15d part (length 80m
In (m), (1) and (2) were respectively connected at a needle movement rate of 3 needles / cm so that the distance between the base fabrics 19a and 19b was 30 mm.

The bag obtained had a very small folding thickness and there was no problem in the developed shape.

Comparative Example 1 In Example 1, an airbag was formed by using the same woven fabric as the main body base cloth without forming the connecting portions (4a, 4b, and 5) between the main body base cloths with the sewing thread. Created. That is, instead of connecting 4a and 4b, the sewing width to the base cloths 9a and 9b is 100 mm, and the space between 9a and 9b is 60 mm so as to block the space between the base cloths 9a and 9b at the central portions of the 4a and 4b portions. Sew the fabric so that
30 mm in diameter instead of connecting to each other, with a cut piece cut so that the distance between 9a and 9b is 60 mm over the entire length of 5 stitched portions.
The fabric having three ventilation holes was sewn. The sewing was carried out by using each of the cut pieces on the main body base fabrics 9a and 9b as a sewing thread by using the upper thread and the lower thread as the fifth thread of nylon 66 fiber and the main stitch having the number of hands of 3.5 stitches / cm. Then, the outer periphery was sewn according to Example 1.

The obtained bag had no problem in the developed shape, but the manufacturing process was extremely complicated, and the storage capacity of the bag was large.

Comparative Example 2 In Example 2, the connecting portion 15 was sewn with 15b and 15d.
15a, 15c and 15e without any suturing
Example 2 was carried out in the same manner as in Example 2 except that the portion was sewn by lock stitch without using the thread loosening device at all.

The obtained bag has a small folding thickness, but the stitching of the base cloth at the end of the sewn portion of the connecting portion 15 as a gas flow control member occurs, and the unevenness of the bag surface around the connecting portion 15 occurs. It got bigger.

[0045]

[Table 1]

[0046]

As described above, according to the present invention, it is possible to easily provide a side bag which has the functions of protecting the chest and the head and is robust and which is excellent in the expanded shape and the initial expandability.

[Brief description of drawings]

FIG. 1 is a side view of a side bag that is an embodiment of the present invention.

FIG. 2 is a side view of a side bag which is another embodiment of the present invention.

FIG. 3 is a sectional view taken along the line AA of FIG. 2 after being developed. Of the connected suture portions 15, 15a, 15c, and 15e are in close contact with the main body base cloths 19a and 19b, and 15b and 15d are in the main body base cloths 19a and 19b.

[Explanation of symbols]

1, 11 ... Side bag 2, 12 ... Chest protection part 3, 13 ... Head protection part 4a, 4b, 14 ... Spaced connection part 5, 15 ... Spaced connection part 15a, 15c, 15e ... Portions 15b, 15d of the connecting portion to which the main body base cloth is in close contact ... Portions 6a, 6b, 16a, 16b of the connecting portion where the main body base cloth is spaced. , 7b, 17a, 17b ... Inflator mounting hole 8, 18 ... Inflator insertion opening 9a, 9b, 19a, 19b ... Bag body base cloth 20 ... Suture thread used for connection

Claims (5)

[Claims] 1. An airbag for side collision protection, which is formed by stitching members together and is mounted so as to protect the occupant's chest and head. The chest protector and head protector of the airbag are provided. In the boundary portion with the portion, at least a part of the stitched portion of the airbag body base cloth except for the outer peripheral portion is connected to each other with a 3 to 100 mm interval by a sewing thread that does not break during deployment. An airbag for a side part, which is characterized in that 2. The side airbag according to claim 1, wherein the connecting portion is further formed on a chest protection portion and / or a head protection portion of the airbag. 3. The heat-resistant fiber yarn having a melting point or a decomposition point higher than the melting point or the decomposition point of the fiber material constituting the airbag body base cloth, wherein the sewing thread is made of a heat-resistant fiber thread. Side airbag. 4. The side airbag according to claim 1, wherein the sewing thread is provided with heat resistance by a heat resistant material. 5. The side airbag according to claim 1, wherein the connecting portion is sewn by continuous stitching or intermittent stitching.