JP6992466B2 - Airbag - Google Patents

Description

The present invention relates to an airbag.

Airbag devices are widely used as safety devices for vehicles such as automobiles. The airbag device is a device that protects an occupant from an impact by expanding and deploying a small folded airbag when an impact of a predetermined value or more is applied to the vehicle from the outside. As an airbag used in this type of device, an airbag that is integrally woven by the One Piece Woven (OPW) method is known (see, for example, Patent Document 1). The airbag manufactured by the OPW method includes a double woven portion constituting the bag portion and a single woven portion surrounding the bag portion.

In this type of airbag, a closed portion made of a single woven portion is formed so as to enter the region of the bag portion in order to adjust the thickness and shape of the bag portion when expanded. The end portion of such a closed portion is formed in a curved shape (particularly, a circular shape or an annular shape) for the purpose of relaxing the stress received when the bag portion expands. A silicone film for preventing air leakage is formed on the surface of this type of airbag.

Japanese Unexamined Patent Publication No. 2011-99198

However, if the outer edge of the end of the closed portion is in contact with the bag portion by a curved line such as a circular shape, a hole large to some extent is formed in the structure of the OPW-type woven fabric constituting the portion when the airbag is inflated. Was sometimes formed. The warp and weft of the single woven portion constituting the closed portion are firmly fixed so as to intersect each other even when the airbag is inflated. On the other hand, since the bag portion at the boundary with the closed portion is composed of a double woven portion having a pair of woven fabrics, the weaving density of each woven fabric is lower than that of the single woven portion, and the warp and weft constituting each woven fabric. And / or the wefts are strongly pulled and easily deformed when the air bag is inflated, so that holes are formed between them. In that case, holes are likely to be formed in the silicone film formed on the surface of the bag portion. As described above, if a hole is formed at the boundary portion between the closed portion and the bag portion when the airbag is expanded, air leakage occurs from the hole and the internal pressure of the airbag is lowered.

It is conceivable to increase the airtightness of the airbag by increasing the thickness of the silicone film formed on the surface of the airbag, but the manufacturing cost will increase. As described above, in the airbag manufactured of the OPW type woven fabric, there is room for improving the shape of the closed portion in contact with the bag portion.

An object of the present invention is to provide an airbag manufactured of an OPW type woven fabric in which air leakage from a boundary portion between a bag portion and an inner closed portion is suppressed.

The airbag according to the present invention is an airbag made of a woven fabric manufactured by an OPW method including a single woven part and a double woven part, and has a bag part made of the double woven part and having a pair of woven fabrics facing each other. , The peripheral closed portion which is composed of the single woven portion and surrounds the peripheral portion, and the peripheral closed portion which is composed of the single woven portion and which surrounds the peripheral portion and is arranged inside the peripheral closed portion. The end of the inner closed portion is annular and has a polygonal portion having a polygonal shape, and the internal angle of the polygonal portion is 150 ° or more. Is.

In the airbag, it is preferable that the polygonal portion has a side along the warp direction of the woven fabric and a side along the weft direction of the woven fabric.

In the airbag, it is preferable that the polygonal portion has a hexagonal shape or a 24-sided shape.

It is preferable that the airbag has a supply path connected to the bag portion and supplies air generated from the inflator to the bag portion, and the polygonal portion is arranged at a position facing the supply path. ..

According to the present invention, it is possible to provide an airbag manufactured of an OPW type woven fabric in which air leakage from a boundary portion between a bag portion and an inner closed portion is suppressed.

Explanatory drawing which shows the state which the airbag of Embodiment 1 was deployed in a plane. Enlarged view of the end of the inner closed portion shown in FIG. Explanatory drawing schematically showing the texture angle of the single woven part and the double woven part In the airbag of Comparative Example 1 before expansion, the boundary portion between the end portion of the inner closed portion composed of the single woven portion and the bag portion composed of the double woven portion, and the texture angle between them is 11.3 °. Explanatory drawing of Explanatory drawing showing how the airbag of Comparative Example 1 shown in FIG. 4 expands and a gap is generated at the boundary portion between the end portion of the inner closed portion and the bag portion. A table in which information on each polygonal portion of Embodiments 1 and 2 and Comparative Examples 2 and 3 is collectively shown. A graph showing the test results of the amount of air leak in each of the airbags of Embodiments 1 and 2 and Comparative Examples 2 to 4.

<Embodiment 1>
Hereinafter, the airbag 1 according to the first embodiment of the present invention will be described with reference to FIGS. 1 to 3. FIG. 1 is an explanatory diagram showing a state in which the airbag 1 of the first embodiment is deployed in a plane. The airbag 1 of the present embodiment is a curtain airbag used in a curtain airbag device for a vehicle. The left side of FIG. 1 corresponds to the front side of the vehicle, and the right side of FIG. 1 corresponds to the rear side of the vehicle. Further, the upper side of FIG. 1 corresponds to the upper side of the vehicle, and the lower side of FIG. 1 corresponds to the lower side of the vehicle.

The airbag 1 has a substantially rectangular shape that extends long along the front-rear direction of the vehicle as a whole. When an impact of a predetermined value or more is applied to the vehicle from the outside (for example, in the case of a rollover or an oblique collision), the airbag 1 is supplied with gas from an inflator (not shown) to provide a side portion of the passenger compartment. It expands and expands along the road to protect the occupants while covering the side window glass and center pillar (B pillar) of the vehicle.

It should be noted that the airbag 1 in a normal state is folded so as to be elongated along the longitudinal direction (vehicle front-rear direction), and in such a folded state, it is attached to the upper end portion of the vehicle interior side portion. It is stored together with the inflator in a certain roof side part.

Such an airbag 1 is made of a bag-shaped woven fabric manufactured by the One Piece Woven method, which is abbreviated as OPW. In the OPW method, a non-sewn bag is formed by weaving two pieces of cloth at the same time (double weaving) and weaving the necessary parts in a single layer. That is, the woven fabric manufactured by the OPW method used for the airbag 1 has a single woven fabric and a double woven fabric. Both the single woven portion and the double woven portion are plain weave, and the weaving density of the single woven portion is higher than that of the double woven portion. The warp threads (warp threads) of the fabric constituting the airbag 1 are arranged in the longitudinal direction (vehicle front-rear direction), and the warp threads (weft threads) are arranged in the lateral direction (vehicle vertical direction). The weaving density of the warp threads of the woven fabric is 54.5 threads / inch, and the weaving density of the weft threads is 45.5 threads / inch. The warp and weft of the woven fabric are made of synthetic fibers such as polyester.

Further, a silicone film (not shown) is formed on each surface (both sides) of the OPW type woven fabric used for the airbag 1 by a known method. The OPW type woven fabric in the original state is cut into a predetermined shape in order to form the airbag 1 after the silicone films are formed on both sides.

The airbag 1 is composed of a main body portion 2 having a substantially rectangular bag body extending in the front-rear direction of the vehicle and a portion protruding outward from the main body portion 2, and a supply unit 3 to which gas from an inflator is supplied. And have. The supply portion 3 is provided substantially in the center of the upper edge portion of the main body portion 2 extending in the longitudinal direction.

The airbag 1 is provided in the main body portion 2 and includes a bag portion 4 made of two woven fabrics (double woven portions) manufactured by the OPW method. FIG. 1 shows a woven fabric 41 on the front side of a pair of woven fabrics constituting the bag portion 4 facing each other. Further, the airbag 1 is composed of a single woven portion manufactured by the OPW method, and is composed of a peripheral edge closing portion 5 surrounding the bag portion 4 and a single woven portion manufactured by the OPW method, and is a peripheral closed portion surrounding the bag portion 4. It is arranged inside the 5 and includes an inner closing portion 6 for adjusting the shape and thickness of the bag portion 4 at the time of expansion. As shown in FIG. 1, the inner closing portion 6 is shaped so as to enter the region of the bag portion 4 when the airbag 1 is unfolded and viewed in a plane. The inner closing portion 6 is formed so as to border the bag portion 4 together with the peripheral closing portion 5.

The inner closing portion 6 includes an inner closing portion 6a formed on the front side of the vehicle of the main body portion 2, an inner closing portion 6b formed substantially in the center of the main body portion 2, and a rear side of the vehicle from the substantially central side of the main body portion 2. It is provided with an inner closing portion 6c formed over the sides. The ends 61, 62, 63, 64 of each inner closing portion 6 are formed in an annular shape, respectively. As will be described later, the end portion 61 of the inner closed portion 6 is formed so that a part of the annular portion forms a part of a polygonal shape (hexagonal shape).

The supply unit 3 is a portion that has a substantially cylindrical shape when expanded, and is connected to the bag portion 4 of the main body portion 2. The entrance 3a of the supply unit 3 is shaped so as to face the rear side of the vehicle. The side edge portion of the supply portion 3 is formed of a single woven portion manufactured by the OPW method, and a closed portion 3b for the supply portion connected to the peripheral edge closed portion 5 is formed.

An inflator (not shown) is attached to the entrance 3a of the supply unit 3. The gas ejected from the inflator is supplied into the bag portion 4 of the main body portion 2 via the supply portion 3. A diffuser (not shown) is provided inside the supply unit 3, and the gas ejected from the inflator is distributed to the front side of the vehicle and the rear side of the vehicle by the diffuser. As shown in FIG. 1, a part of the gas from the inflator supplied into the bag portion 4 via the supply portion 3 is the end portion 61 of the inner closing portion 6a formed on the vehicle front side of the main body portion 2. It is supplied toward the side (see arrow G in FIG. 1). Then, the partial bag portion 4a or the like formed between the inner closed portion 6a and the other inner closed portion 6b, which is a part of the bag portion 4, expands vigorously.

FIG. 2 is an enlarged view of the end portion 61 of the inner closed portion 6a shown in FIG. As shown in FIG. 2, the end portion 61 of the inner closed portion 6a forms an annular shape drawn with a predetermined line width, and a part thereof forms a part of a hexagonal shape. As described above, the inner closed portion 6 such as the inner closed portion 6a is composed of the single woven portion W1 manufactured by the OPW method, and the bag portion 4 is composed of the double woven portion W2 manufactured by the OPW method. The peripheral edge closing portion 5 surrounding the bag portion 4 is also made of the single woven portion W1 manufactured by the OPW method, like the inner closing portion 6. The inside of the annular end 61 of the inner closing portion 6 is composed of the double woven portion W2, but does not expand. Further, in the main body portion 2, the margin portion on the outside of the peripheral edge closing portion 5 is a connecting portion to which the double woven portion is partially connected.

Of the annular end 61, the hexagonal polygonal portion 61a occupies about 50% of the end 61. The outer edge of the polygonal portion 61a (the edge on the side in contact with the bag portion 4) is 0 °, 26.6 °, or 45 with respect to the warp direction (horizontal direction in FIG. 2) or the weft direction (vertical direction in FIG. 2). It has an angle of °. That is, the outer edge of the polygonal portion 61a is formed by three types of lines: a line forming an angle of 0 °, a line forming an angle of 26.6 °, and a line forming an angle of 45 ° with respect to the warp direction or the weft direction. It is expressed. The polygonal portion 61a has a side along the warp direction of the woven fabric (a side forming 0 ° with respect to the warp direction) and a side along the weft direction of the woven fabric (a side forming 0 ° with respect to the weft direction). Have.

FIG. 3 is an explanatory diagram schematically showing the texture angles of the single woven portion W1 and the double woven portion W2. FIG. 3A is an explanatory diagram when the texture angle between the single woven portion W1 and the double woven portion W2 is 0 °, and FIG. 3B is an explanatory diagram when the texture angle between the single woven portion W1 and the double woven portion W2 is 11. It is an explanatory diagram in the case of 3 °, FIG. 3 (C) is an explanatory diagram in the case where the texture angle of the single woven portion W1 and the double woven portion W2 is 18.4 °, and FIG. 3 (D) is an explanatory diagram of the single woven portion. It is explanatory drawing when the cloth angle of W1 and the double woven part W2 is 26.6 °, and FIG. 3 (E) is the explanatory view when the cloth angle of a single woven part W1 and a double woven part W2 is 33.7 °. 3 (F) is an explanatory diagram when the texture angle between the single woven portion W1 and the double woven portion W2 is 45 °.

One of the squares separated by the grid shown in FIG. 3 represents a place where one warp and one weft intersect. Further, the uncolored square portion corresponds to the outer edge (boundary portion) of the double woven portion W2 constituting the bag portion, and the colored square portion corresponds to the single woven portion W1 constituting the peripheral edge closing portion. Corresponds to the outer edge (boundary part) of. The polygonal portion 61a of the inner closed portion 6a in the present embodiment shown in FIG. 2 has texture angles of 0 °, 26, 6 shown in FIGS. 3 (A), 3 (D), and 3 (F), respectively. Expressed by ° and 45 °.

In the airbag 1 of the present embodiment, the formation of holes in the woven fabric at the boundary between the end portion 61 of the inner closing portion 6 and the bag portion 4 is suppressed during expansion and deployment. For example, gas is supplied from the inflator, and the bag portion 4 (for example, the partial bag portion 4a formed between the inner closed portion 6a and the other inner closed portion 6b) is vigorously supplied. Even if each warp and weft of the double woven portion W2 (partial bag portion 4a) at the boundary portion with the single woven portion W1 (end portion 61a) is pulled due to expansion, that portion (end portion 61 of the inner closing portion 6a) is pulled. It is possible to prevent the formation of a gap that causes air leakage in the portion of the bag portion 4 in contact with the bag portion 4).

<Comparative Example 1>
Next, with reference to FIGS. 4 and 5, the gap S generated at the boundary between the end portion of the inner closed portion and the bag portion when the airbag of Comparative Example 1 is expanded will be described. FIG. 4 shows the boundary portion between the end portion 61P of the inner closed portion 6P made of the single woven portion W1 and the bag portion 4P made of the double woven portion W2 in the airbag of Comparative Example 1 before expansion, and the texture thereof. It is explanatory drawing when the angle is 11.3 °, and FIG. 5 shows in FIG. 5 that the airbag of Comparative Example 1 shown in FIG. It is explanatory drawing which shows the state that the gap S occurs.

In the airbag of Comparative Example 1 described here, a part of the end portion 61P of the inner closed portion 6P is a polygonal portion 61Pa, but the outer edge of the polygonal portion 61Pa is a warp (FIGS. 4 and 5). It includes a portion where the angle with respect to the weft (vertical direction in FIGS. 4 and 5) is 11.3 °. The airbag of Comparative Example 1 is the same as the airbag 1 of the first embodiment except for the configuration of the polygonal portion 61 Pa.

As shown in FIG. 4, the polygonal portion 61Pa of the inner closed portion 6P composed of the single woven portion W1 is represented by the colored squares among the squares divided in a grid pattern. On the other hand, the bag portion 4P composed of the double woven portion W2 is shown by vertically long and horizontally long rectangles smaller than the squares for convenience of explanation. In FIGS. 4 and 5, the bag portion 4P is represented by alternating rectangles long in the warp direction and rectangles long in the weft direction. Here, the warp is expressed by arranging a plurality of rectangles long in the warp direction, and the weft is expressed by arranging a plurality of rectangles long in the weft direction.

As shown in FIG. 5, when the airbag of Comparative Example 1 expands, the warp and weft constituting the bag portion 4P adjacent to the polygonal portion 61a of the inner closed portion 6P are pulled. Then, as shown in FIG. 5, a gap S that causes air leakage is formed between the warps adjacent to each other. Further, although not shown in FIG. 5, a gap is formed between adjacent wefts depending on the location. Even if the airbag expands, the warp and weft of the single woven portion W1 constituting the inner closed portion 6P are fixed so as to cross each other, and a gap for air leakage is not formed. However, when the bag portion 4P composed of the double weave portion W1 is adjacent to such a single woven portion W1 at a predetermined angle, the bag portion 4P is connected to the bag portion 4P as described above. At the time of expansion, a gap is formed between the warp and weft constituting the bag portion 4P.

<Embodiment 2>
An airbag having the same configuration as that of the first embodiment (air of the second embodiment) except that the shape of the polygonal portion 61a of the inner closing portion 6a in the airbag 1 of the first embodiment is changed from a hexadecagon to a 24-square shape. Bag) was made. The outer edge of the polygonal portion of the inner closed portion of the second embodiment is 0 °, 18.4 °, 26.6 ° or 45 ° with respect to the warp and weft direction. That is, the outer edge of the polygonal portion of the second embodiment is a line forming an angle of 0 °, a line forming an angle of 18.4 °, a line forming an angle of 26.6 °, and a line forming an angle of 26.6 ° with respect to the warp direction or the weft direction. It is represented by four types of lines forming an angle of 45 °.

<Comparative Example 2>
An airbag having the same configuration as that of the first embodiment (air of Comparative Example 2) except that the shape of the polygonal portion 61a of the inner closed portion 6a in the airbag 1 of the first embodiment is changed from a hexadecagon to an octagon. Bag) was made. The outer edge of the polygonal portion of the inner closed portion of Comparative Example 2 is 0 ° or 45 ° with respect to the warp and weft direction. That is, the outer edge of the polygonal portion of Comparative Example 2 is represented by two types of lines, a line forming an angle of 0 ° and a line forming an angle of 45 ° with respect to the warp and weft direction.

<Comparative Example 3>
An airbag having the same configuration as that of the first embodiment (air of Comparative Example 3) except that the shape of the polygonal portion 61a of the inner closing portion 6a in the airbag 1 of the first embodiment is changed from a hexadecagon to a 40-sided shape. Bag) was made. The outer edge of the polygonal portion of the inner closed portion of Comparative Example 3 is 0 °, 11.3 °, 18.4 °, 26.6 °, 33.7 ° or 45 ° with respect to the warp direction or the weft direction. Is doing. That is, the outer edge of the polygonal portion of Comparative Example 3 is a line forming an angle of 0 ° with respect to the warp or weft direction, a line forming an angle of 11.3 °, and a line forming an angle of 26.6 °. It is represented by six types of lines, a line forming an angle of 33.7 ° and a line forming an angle of 45 °.

<Comparative Example 4>
An airbag having the same configuration as that of the first embodiment (airbag of Comparative Example 4) except that the shape of the polygonal portion 61a of the inner closing portion 6a in the airbag 1 of the first embodiment is changed from a hexadecagon to a circular shape. ) Was produced.

In addition, the polygonal shape used for each polygonal portion of Embodiments 1 and 2 and Comparative Examples 2 and 3, the relationship between the outer angle and the inner angle of the polygonal portion, the constituent angle (outer angle) and the constituent angle (inner angle) are summarized in a table. The thing is shown in FIG.

<Confirmation test of air leak amount>
For each of the airbags of Embodiments 1 and 2 and Comparative Examples 2 to 4, the amount of air leak was measured by the method shown below. The measurement results are shown in FIG.

The tip of a hose connected to the air source via a pressure gauge was inserted into the airbag through the inlet of the supply path. A pressure sensor for measuring the pressure inside the airbag is attached to the tip of the hose. Next, with the hose inserted, the entrance of the supply path was crimped so that the air in the airbag did not leak to the outside from the entrance of the supply path. Then, air was supplied from the air source into the airbag via a hose to inflate the airbag. Then, after confirming that the air pressure display of the pressure measuring instrument is 0 kPa, air of a predetermined pressure is supplied into the airbag from there, and the pressure (kPa) in the airbag and the air leak amount (L / min). Was measured. The amount of air leak (L / min) is measured by a flow meter provided in the middle of the hose as the amount of air supplied into the airbag via the hose. While gradually increasing the air supply pressure, the pressure inside the airbag (kPa) and the amount of air leak (L / min) are measured, and finally, until the air supply pressure reaches 100 kPa, the inside of the airbag The pressure (kPa) and the amount of air leak (L / min) were measured.

FIG. 7 is a graph showing the test results of the air leak amount of each of the airbags of the first and second embodiments and the comparative examples 2 to 4. The horizontal axis of the graph shown in FIG. 7 represents the internal pressure (kPa) of the airbag (bag portion), and the vertical axis thereof represents the amount of leakage (L / min) from the airbag (bag portion). As shown in the graph of FIG. 7, when the shape of the polygonal portion of the inner closed portion is a hexadecagon, when it is a 24-sided portion, and when the end portion of the inner closed portion is an annular shape, there is a case of Comparative Example 4. In comparison, it was confirmed that the amount of air leak was reduced. The internal angle of the polygonal portions of the first and second embodiments is 150 ° or more.

On the other hand, in the case of Comparative Example 2 in which the shape of the polygonal portion of the inner closed portion is an octagon and in the case of Comparative Example 3 in which the shape of the polygonal portion of the inner closed portion is an octagon, in Comparative Example 4 in which the end portion of the inner closed portion is annular. It was confirmed that the amount of air leak was larger than in the case. In the case of Comparative Example 2, it is presumed that an air leak occurred because the internal angle of the polygonal portion was 135 ° and a hole was formed in the bag portion near the corner portion. In the case of Comparative Example 3, 11.3 ° and 33.7 ° are used as the outer angles constituting the polygonal portion (see FIGS. 3B and 3E). It is presumed that air leaks occur in these outer angles because gaps are more likely to be formed in the fabric as compared with other outer angles.

<Other embodiments>
The present invention is not limited to the embodiments described above and the drawings, and for example, the following embodiments are also included in the technical scope of the present invention.

(1) The airbag of the present invention is not particularly limited as long as the object of the present invention is not impaired. For example, side airbags, knee airbags, driver airbags, passenger airbags, ITS head airbags, etc. Used for vehicle airbags such as pedestrian protection airbags. Further, the airbag of the present invention may be used for an airbag other than that for a vehicle as long as the object of the present invention is not impaired.

(2) In the first embodiment and the like, the polygonal portion is provided only at the end of the inner closed portion formed on the front side of the vehicle of the main body portion, but in other embodiments, other embodiments are provided. A polygonal portion may be formed at the end of the inner closed portion of the portion.

(3) In the first embodiment and the like, the polygonal portion is formed so as to occupy about 50% of the end portion of the inner closed portion, but the polygonal portion is one end portion as long as the object of the present invention is not impaired. The ratio to the above is not limited, but for example, 30% or more is preferable, and 40% or more is more preferable.

1 ... Airbag (curtain airbag), 2 ... Main body, 3 ... Supply, 4 ... Bag, 5 ... Peripheral closed, 6 ... Inner closed, 61 ... Inner closed end, 61a ... Polygonal , S ... Gap, W1 ... Single weave, W2 ... Double weave

Claims (4)

An airbag made of a woven fabric manufactured by the OPW method including a single woven fabric and a double woven fabric.
A bag portion composed of the double woven portion and having a pair of woven fabrics facing each other, and a bag portion.
A peripherally closed portion composed of the single woven portion and surrounding the bag portion,
It is composed of the single woven portion, is arranged inside the peripheral edge closing portion that surrounds the bag portion, and is provided with the peripheral edge closing portion and an inner closing portion that borders the bag portion.
The end of the inner closed portion has an annular shape and, in a part thereof, has a polygonal portion having a polygonal shape.
An airbag in which the internal angle of the polygonal portion is 150 ° or more, and the polygonal portion has a hexagonal shape or a 24 -sided shape. An airbag made of a woven fabric manufactured by the OPW method including a single woven fabric and a double woven fabric.
A bag portion composed of the double woven portion and having a pair of woven fabrics facing each other, and a bag portion.
A peripherally closed portion composed of the single woven portion and surrounding the bag portion,
It is composed of the single woven portion, is arranged inside the peripheral edge closing portion that surrounds the bag portion, and is provided with the peripheral edge closing portion and an inner closing portion that borders the bag portion.
The end of the inner closed portion has an annular shape and, in a part thereof, has a polygonal portion having a polygonal shape.
An airbag in which the internal angle of the polygonal portion is 150 ° or more, and the texture angle between the polygonal portion and the bag portion is not larger than 0 ° and smaller than 18.4 °. The airbag according to claim 1 or 2 , wherein the polygonal portion has a side along the warp direction of the woven fabric and a side along the weft direction of the woven fabric. It is connected to the bag portion and has a supply path for supplying air generated from the inflator to the bag portion.
The airbag according to any one of claims 1 to 3, wherein the polygonal portion is arranged at a position facing the supply path.

Images