JP2010023718A - Airbag - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an airbag that can be easily produced by arbitrarily adjusting its airtightness. <P>SOLUTION: There are provided a first welding portion formed by stacking a plurality of cloths and welding peripheral edges thereof and a second welding portion, in an embossed form or a linear form inside the first welding portion, to be formed into a bag-like shape as a whole. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an airbag that is mounted on a vehicle or the like and protects an occupant from an impact such as a collision or rollover, and in particular, can provide a joint that can secure or adjust the confidentiality of the airbag. It relates to airbags.

  Conventionally, as an airbag, a joint portion by an isocyanate-terminated polyurethane-based hot melt adhesive is reinforced by stitching, and a void formed in the joint portion by the stitching is sealed by remelting and solidifying the hot melt adhesive. There has been proposed an air bag characterized by the above.

  Certainly, such an airbag is excellent in that it can provide an automotive airbag having excellent characteristics of impact resistance during high-temperature expansion.

  However, airbags are used in various places such as for driver's seats, passenger seats, and rear seats, and are used properly depending on the manner of frontal collision or side collision. In addition, automobiles in which airbags are used vary from general sedan types to mini cars, RV cars, and the like. The airbag needs to have a change in its airtightness depending on the position and use of the airbag. For example, in the case of a general sedan type automobile, since there are many normal collision accidents, it is preferable to immediately contract after inflating instantaneously. The air bag used for such an automobile does not require such high confidentiality. On the other hand, if the airtightness is too high, it is difficult for the occupant to escape from the automobile. On the other hand, in the case of a so-called SUV or RV vehicle having a high vehicle height, there are many cases where the vehicle rolls over due to an accident as compared with a general sedan type vehicle. In the case of such an automobile with a high possibility of rollover, it is necessary to protect the occupant by maintaining the inflated state for several seconds to several tens of seconds. In such a case, an air bag having higher airtightness is required.

Japanese Patent Laid-Open No. 10-102029

  Therefore, the present inventor has been made in view of the above problems, and provides an airbag that can be arbitrarily adjusted in airtightness and can be easily manufactured.

  In order to solve the problems as described above, the measures taken by the present invention are as follows.

  The airbag according to the first aspect of the present invention includes a first welded portion in which a plurality of fabrics are overlapped to weld an outer peripheral edge portion, and an embossed or linear second on the inner side of the first welded portion. A welding part is provided, and the whole is formed in a bag shape.

  The airbag according to claim 1 employs a means of welding at the joint. By adopting the means of welding, the first welded portion formed on the outer peripheral edge can be joined with the entire outer peripheral edge being completely sealed. Further, the first welded portion may be formed so that a part or the whole is peeled off by adjusting the weld width of the first welded portion when the airbag is inflated due to an accident of an automobile or the like. That is, when expanded due to the welding width, the joined state can be maintained completely and the sealed state can be maintained, or the joined state can be peeled off at a considerable portion, so that an air hole can be formed at the time of expansion. it can. Therefore, the airtightness during expansion can be changed by the bonding strength of the first welded portion. Further, by using the means of welding, the outer peripheral edge can be welded at the same time as the outer peripheral edge is joined, and the outer circumference can be cut by melting at the same time as joining in the bag shape. Further, by adopting a means of fusing, the outer peripheral edge portion is formed in a molten state, and a function to prevent the fabric from fraying can be provided.

  On the other hand, as a general rule, the second welded portion is welded so as not to be peeled off even when the airbag is inflated. The joining shape of the second welded portion can be variously changed, and for example, if formed on a straight line as shown in FIG. Further, as shown in FIGS. 5B to 5D, an air passage can be provided by combining dotted lines and diagonal lines. The degree of air escape can be adjusted by the shape of the second welded portion.

  The airbag according to the second aspect of the present invention is the airbag according to claim 1, wherein a sewing portion is provided inside the second welded portion.

  This is reinforced by sewing the inside of the welded portion with a thread when a higher bonding strength is required.

  Further, the airbag according to the invention of claim 3 is characterized in that an adhesive sheet or a hot melt adhesive is provided between the fabrics of the welded portion.

  In this case, when a higher bonding strength is required, an adhesive sheet or a hot melt adhesive is provided between the fabrics to be bonded to ensure a high bonding strength.

  Further, the airbag according to the invention of claim 4 is characterized in that the sewing portion is coated with a covering material for preventing air leakage.

  In order to improve the sealing property of the sewing part, it is coated with a covering material after sewing.

  The effects obtained by adopting the above means are as follows.

  According to the present invention, by adopting the means of welding, it is possible to join in various forms of welding, so that airbags having various sealing properties can be manufactured in a short process.

  Hereinafter, an optimum embodiment of an airbag will be described in detail with reference to the drawings. In addition, the Example and drawing demonstrated below illustrate the optimal form of the Example of this invention, and is not used for the objective limited to these structures.

The airbag of the present invention will be described below by taking an airbag used for a driver's seat handle as an example. FIG. 1 is a perspective view of the airbag according to the first embodiment. 2 and 3 are cross-sectional views thereof. It is a top view of the state before making the front and back of the airbag of FIG. 4 reverse.

The airbag 100 of Example 1 has the front side fabric 10 and the back side fabric 11, as shown in FIGS. 1-4, The circumference | surroundings are joined by ultrasonic welding and it is made into a bag shape. In FIG. 1, since the front and back are reversed, the outer peripheral welded portion is formed on the inner side. FIG. 4 shows a state prior to turning upside down. A gas hole 12 for inserting a high-pressure gas into the airbag at the time of a collision is provided at the approximate center of the back fabric 11. Further, a plurality of small mounting holes 13 and air vent holes 14 for venting air once introduced into the airbag are provided around the periphery.

  Since the fabric used for the airbag according to Example 1 needs to be joined by welding, a synthetic fiber fabric is used. The synthetic fiber is not particularly limited, and various synthetic fibers such as polyethylene, polyester, PET, and polyamide can be used. The structure may be any of plain weave, twill, satin fold, etc., and is not particularly limited.

  As shown in FIGS. 3 and 4, the outer periphery of the fabric has a first welded portion 20 formed by welding the outer peripheral edge. The entire outer periphery of the first welded portion 20 is welded and is completely sealed. A second welded portion 21 is provided inside the first welded portion 20. The second welded portion 21 is provided with an embossed welded portion (FIG. 4 is shown in an embossed shape) having a straight line or an interval without any spacing on the inner side of about 3 mm to about 1 cm from the first welded portion 20. Yes. As an example of the shape of the emboss, it may be a simple point as shown in FIG. 4 or may be a wavy line as shown in FIG. 5-b, and is applied obliquely as shown in FIG. 5-d. It may be a thing. Further, as shown in FIG. 5C, two lines may be provided by embossing. By appropriately selecting the form of welding in this way, in the case of a straight line as shown in FIG. 5-a, it is possible to achieve complete sealing in addition to the outer periphery, as shown in FIGS. If it is adopted, it is possible to adjust the degree of escape of internal air depending on the form. Therefore, the sealing property can be freely adjusted by appropriately selecting the welding form.

Further, a welded portion other than the first welded portion 20 and the second welded portion 21 may be provided. For example, a cloth for securing strength may be welded to a portion where a large force is applied, such as the gas hole 12, and the periphery of the gas hole 12, the mounting hole 13 and the air vent hole 14 may be welded to fray the cloth. A stop function may be provided.

  When higher bonding strength is required, a hot melt adhesive may be provided between the fabrics to be bonded, or a sheet having adhesiveness may be disposed. As the welding means, for example, hot pressing, high-frequency heating or the like can be used, but ultrasonic welding is preferable.

  Furthermore, when the bonding strength is not sufficient only by welding, the sewing part 22 may be provided on a part or the whole inside the second welding part 21. The sewing in the sewing may be a sewing method normally used for airbags such as main sewing and double chain stitching. Moreover, the thread | yarn used for sewing is not limited.

  Further, at least the seam portion may be coated with a covering material in order to prevent air from coming off due to the seam. The covering material may be appropriately selected from silicone resin, polyurethane resin, chloroprene rubber and the like.

  The airbag as described above first prepares an original fabric used for the airbag and cuts the back side fabric. For the cutting, the gas hole 12, the mounting hole 13, and the air vent hole 14 are simultaneously blown using ultrasonic fusing so as to be a circle that is slightly larger than the outer peripheral edge. Furthermore, this back side fabric is overlapped on the raw fabric for the front side fabric, and the outer peripheral edge portion is melted, and at the same time, the first welded portion 20 and the second welded portion 21 are provided to join the front side fabric. Then, if necessary, the airbag is completed by sewing the inside of the second welded portion and reversing the front and back as shown in FIGS. Of course, it can also be used as it is, without reversing the front and back.

  Thus, the airbag of the present invention can be manufactured in a very short process.

  Although the above embodiment has been described using a driver's seat airbag, it can of course be applied to a rear seat airbag or a side airbag.

1 is a perspective view of an airbag according to Embodiment 1. FIG. 1 is a side sectional view of an airbag according to Embodiment 1. FIG. It is the elements on larger scale of the side sectional view of the airbag concerning Example 1. It is a front view before making the airbag which concerns on Example 1 upside down. It is the figure on which the variation of the welding part which concerns on Example 1 was drawn.

Explanation of symbols

DESCRIPTION OF SYMBOLS 100 Airbag 10 Front side fabric 11 Back side fabric 12 Gas hole 13 Attachment hole 14 Air vent hole 20 1st welding part 21 2nd welding part 22 Sewing part

Claims (4)

A first weld portion in which a plurality of fabrics are overlapped to weld the outer peripheral edge portion;
An embossed or linear second welded portion is provided inside the first welded portion,
An air bag characterized by being formed into a bag shape as a whole.   The airbag according to claim 1, wherein a sewing part is provided inside the second welding part.   The airbag according to claim 1, wherein an adhesive sheet or a hot melt adhesive is provided between the fabrics of the welded portion. The airbag according to claim 2, wherein the sewing portion is coated with a covering material that prevents air leakage.

Images