JPH09272388A - Manufacture of vehicle air bag - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a manufacture of a vehicle air bag which is provided with holes on the predetermined portions of a base cloth comprising the air bag, putting stitches around the holes, wherein the stitches are firmly put from the beginning so as to improve productivity. SOLUTION: On putting stitches around a mounting hole and vent hole 5, stitching is started from the inside of an area 51 to be bored therewithin, and proceeded so as to put stitches around the periphery of the area 51. Thereafter, the boring intended area 51 is bored so that the starting portion with loose stitches is removed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of manufacturing an airbag in a vehicle airbag device which is an occupant protection device.

[0002]

2. Description of the Related Art An air bag for a vehicle is designed to expand and protect an occupant in the event of a vehicle collision, and a gas generator is installed in an air bag device arranged in a vehicle instrument panel or a central portion of a steering wheel. It is stored together with an inflator and inflated by the gas emitted by the inflator.

Such an airbag is formed in a bag shape from one or a plurality of base cloths, and is usually used for attaching an inflator and for letting out gas in the airbag after inflation. Has a vent hole.
Then, reinforcement sewing is applied around these holes.

For example, in the conventional driver airbag 100 shown in FIG. 6, two substantially circular bases are formed by known cutting means such as punch cutting, knife cutting and laser cutting of cloth such as woven cloth. Cut into a piece of cloth, and inflate the cloth on one side (101)
The other side is used as the occupant side cloth (102), and the both sides are polymerized and the outer peripheral edge portion is sewn to form a bag shape.
The inflator side cloth (101) is formed with a circular mounting hole (103) for mounting the inflator in the central portion, and two circular vents having a diameter smaller than the mounting hole (103) are formed in the slightly outer periphery thereof. Holes (104) (104) are formed and both cloths (10
1) After the outer peripheral edge of (102) is sewn (as shown in FIG. 6), the occupant side cloth (102) is pulled out from the mounting hole (103) and turned over to form a bag-shaped airbag (100). .

The holes (103), (104) and (104) provided in the inflator side cloth (101) are provided before the suture with the occupant side cloth (102).
A circular reinforcing cloth (1
It is formed by overlapping 05), sewing (106) so as to surround the outer periphery of the planned drilling area, sewing the reinforcing cloth (105), and then punching the drilled area.

[0006]

[Problems to be Solved by the Invention] The holes (103) (104) (1)
Since the sewing (106) to be performed on 04) is performed using a sewing machine such as a sewing machine, a sewing run-up portion of about 10 stitches is usually provided to ensure that the upper thread and the lower thread are entangled at the sewing start portion. However, in consideration of this sewing run-up part and the thread play length before the sewing machine is activated, the thread end (1
The play amount of 07) is considerably long (about 50-60 mm),
As a result, it may be unfavorable for the subsequent workability in assembling the airbag (100) and the inflator. Therefore, when the play amount of the thread end (107) at the sewing start portion is large, there is a problem that the thread end (107) must be manually cut.

Therefore, according to the present invention, when an airbag provided with a hole in a base cloth and sewn to reinforce the hole is manufactured, the amount of play of the yarn end is reduced and the workability is excellent. An object of the present invention is to provide a method for manufacturing a vehicle airbag.

[0008]

The method for manufacturing a vehicle airbag according to claim 1 of the present invention is provided with a hole at a predetermined position of the base fabric constituting the airbag, and sewing is performed around the hole. In the method of manufacturing an airbag for a vehicle, the sewing is started from within a region in which the hole is to be drilled so as to surround the outer periphery of the region, and the region is punched after the sewing.

According to a second aspect of the present invention, there is provided a method for manufacturing an airbag for a vehicle, wherein a base cloth forming the airbag has holes at predetermined positions,
In a method for manufacturing a vehicle airbag in which a reinforcing cloth for reinforcing the hole is sewn to the base cloth by sewing around the outer periphery of the hole, the sewing is started from within a planned drilling area of the hole. It is characterized in that it is carried out so as to surround the outer periphery of the region, and the region is perforated after this sewing.

According to the vehicle airbag manufacturing method of the first and second aspects of the invention, the sewing around the hole is started from within the area where the hole is to be drilled, and then the area outside the area is opened. The sewing is performed so as to surround the outer periphery thereof, and after the sewing, the area to be drilled is punched, so that the sewing start portion including the sewing start point is removed by the punching. Therefore, even if the play amount of the thread end at the sewing start portion is large, that part is removed by perforation, so that the play amount of the thread end on the sewing start side becomes 1 pitch or less of the seam, and the thread play amount is reduced. be able to.

A method for manufacturing a vehicle airbag according to a third aspect is the method according to the first or second aspect, in which an area where seam lines overlap is provided outside the planned drilling area and the sewing is completed. Is characterized by.

As described above, since the sewn end portion is sewn on the outside of the perforated region, the fraying of the sewing thread at the end portion can be prevented.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION A method of manufacturing a driver airbag (1) according to an embodiment of the present invention will be described below with reference to the drawings.

As shown in FIG. 1, the airbag (1) is formed of a substantially circular inflator side cloth (2) and an occupant side cloth (3) in a bag shape, and the inflator side cloth (2) is formed. , A circular mounting hole (4) in the center thereof, and two circular vent holes (5) (5) having a diameter slightly smaller than the mounting hole (4) near the outer periphery, and these holes (4 ) (5)
Reinforcing cloth (6) (7) (7) for reinforcing (5) is sewn (8) (9) surrounding the outer circumference of each hole (4) (5) (5).
It is sewn by (9).

When manufacturing this airbag (1),
First, a woven cloth (made of nylon 6,6, 420d, 53 threads / inch) is cut to the same diameter (diameter = 750 mm) by cutting means such as punching, knife cutting, and laser cutting.
The inflator side cloth (2) and the passenger side cloth (3) are cut. Then, after forming the mounting holes (4) and the vent holes (5) and (5) in the inflator side cloth (2), the outer peripheral edge portions of the inflator side cloth (2) and the passenger side cloth (3) are sewn together. Then, by pulling out the occupant side cloth (3) from the mounting hole (4) and turning it over, the bag-shaped airbag (1) shown in FIG. 1 is obtained.

The method of forming the vent holes (5) and (5) and the mounting hole (4) in the inflator side cloth (2) will be described below.

First, a method of forming the vent hole (5) will be described.

As shown in FIG. 2, a circular (diameter = 40 mm) planned drilling area (51), which is an area for forming the vent hole (4) of the inflator side cloth (2), is provided in the area (51).
A circular reinforcing cloth (7) having a larger diameter (diameter = 90 mm) is superposed so as to cover the. As the reinforcing cloth (7), the same woven cloth as that forming the inflator side cloth (2) may be used.

Then, in order to sew the reinforcing cloth (7) to the inflator side cloth (2), a sewing machine (sewing thread; nylon 6,6 (1260d)) is used, and a perforated area (5) is prepared.
Perform sewing (9) surrounding the outer circumference of 1). Sewing (9)
As shown in FIG. 3A, the process starts from inside the perforation-scheduled region (51), goes out of the region (51), and surrounds the outer periphery in a circular shape. That is, the sewing start point (91) is set within the perforated area (51), and the sewing start point (91) is set.
From the specified area to the outside of the area (51).
2) is provided, and the area (5) is provided outside the planned drilling area (51).
A first sewn portion (93) having a concentric seam line with 1) is formed, and a first sewn overlapped portion (94) having the seam line overlapped is formed at the end of the first sewn portion (93). Here, the length of the sewing run-up portion (92) is 30 mm, the diameter of the first sewing portion (93) is 60 mm, and the length of the first sewing overlap portion (94) is 20 m.
m.

After forming the first sewn-over portion (94), the outer periphery of the first sewn portion (93) is further surrounded by a circle, and finally the sewn portion is overlaid to complete the sewing (9). That is, a second sewn portion (95) composed of concentric stitch lines is formed outside the first sewn portion (93), and a terminal stitch overlapped portion where the stitch line overlaps at the end of the second sewn portion (95). (96) is formed, the sewing machine is stopped after this formation, and the upper thread and the lower thread are cut leaving a thread end of about 5 mm. Here, the diameter of the second sewing portion (95) is 75 mm, and the length of the end stitching overlapped portion (96) is 20 mm.
Is set to

After the sewing (9) is performed in this manner, the planned drilling area (51) is punched. The perforation is preferably performed by a fusion cutting means such as a heat cutter that does not cause fraying of the yarn by fusing the cut ends. As a result, FIG.
As shown in (b), the sewing start point (91) and the sewing run-up portion (92) are removed together with the central portion of the reinforcing cloth (9) to form the vent hole (5).

When forming the mounting hole (4), as shown in FIG. 2, as in the case of the vent hole (5), the circular planned drilling area (41) should cover the area (41). The circular reinforcing cloths (6) are overlapped, and the sewing (8) is started from within the area (41), and the sewing run-up portion (82) and the first and second sewing portions (83) (85) are formed. After arranging, the sewn end overlapped part (86) is provided and the sewing (8) is finished, and the reinforcing cloth (6) is sewn to the inflator side cloth (2) by this sewing (8), and then drilling is planned. The area (41) is perforated to remove the sewing start point (81) and the sewing run-up portion (82).

As described above, according to the method of manufacturing the airbag (1) of the present embodiment, the sewing start points (81) (91) are provided in the perforated regions (41) (51), and the subsequent Since the sewing start points (81) and (91) are removed by piercing, the thread play amount on the sewing start side can be set to 1 pitch or less of the seam. Therefore, the play amount of the thread end on the sewing start side can be substantially reduced. It can be lost.

Further, the sewing run-up portions (82) (92) having a predetermined length are provided in the planned drilling areas (41) (51), and the sewing run-up portions (82) (92) are removed by punching. It is possible to eliminate thread play due to the degree of entanglement between the upper thread and the lower thread when the sewing machine is operated.

The lengths of the sewing run-up portions (82) and (92) are the same as those of the inflator side cloth (2) and the reinforcing cloths (6) and (7), and the threads used for sewing (8) and (9). Although it depends on the type and other configurations, it is usually preferable that it is 20 to 50 mm from the viewpoint of reducing the play amount of the yarn end.

Further, the end portions of the sewing (8) (9) arranged on the outside of the planned drilling areas (41) (51) are sewn together,
Since the terminal end stitching overlapped portions (86) (96) are formed, it is possible to prevent the thread from fraying at the terminal end portions of the sewing (8) (9). In order to sufficiently secure the effect of preventing the thread fraying, the length of the end stitching overlapped portions (86) (96) is 5
It is preferably about 20 mm.

FIG. 4 shows a constitutional example of the vent hole (5) in another embodiment of the present invention. In this example, the reinforcing cloth (7) is not sewn on the outer periphery of the vent hole (5), and only the sewing (9) is applied around the vent hole (5). In the sewing (9), the sewing start point (91) is set in the planned drilling area (51) and a predetermined sewing runner (92) is provided in the area (51), as in the above-described embodiment. , The outer periphery of the region (51) is surrounded. However, in this embodiment, the sewing (9) forms a sewing portion (97) consisting of a circular seam line that surrounds the outer periphery of the planned drilling area (51), and the sewing portion (97) Finally, the end stitch overlapped portion (96) where the seam lines overlap is formed, and the process ends.

As described above, the sewing (9) provided around the vent hole (5) may have a single seam line, and the present invention can be applied even when the reinforcing cloth (7) is not provided. is there. The mounting hole (4) can also have the same structure.

FIG. 5 shows a constitutional example of the mounting hole (4) in still another embodiment of the present invention. Also in this example, when sewing (8) around the attachment hole (4), the sewing start point (81) and the sewing run-up portion (82) are provided in the planned drilling area (41), and the sewing (8) is performed. An end stitching overlap portion (86) is provided at the end portion of. However, in this example,
The sewn portion (88) provided around the attachment hole (4) is formed by a quadruple seam line, and the shape of the seam line is not limited to the circular shape as in the above-mentioned embodiment, There is also a substantially rectangular shape.

As described above, when the sewing start point (81) is provided in the planned drilling area (41) and the terminal stitch overlapping portion (86) is provided at the end of the sewing (8), the attachment hole (4 The shape of the sewing (8) surrounding the outer periphery of () is not particularly limited.

The present invention is not limited to the mounting hole (4) and the vent hole (5) described above, but can be applied to various holes of a vehicle airbag, and the type of airbag is also a driver's seat. The present invention is not limited to a passenger airbag, but can be applied to a passenger airbag or a vehicle airbag arranged in another place.

[0032]

According to the vehicle airbag manufacturing method of the first and second aspects of the present invention, the sewing start portion for sewing around the hole is provided in the planned drilling area of the hole, and the area is punched after the sewing. Since the sewing start portion is provided and the play start portion is removed, it is possible to reduce the play amount of the thread end on the sewing start side where the play amount of the thread end tends to be large, and thus the workability in the subsequent manufacturing process is excellent.

According to the vehicle airbag manufacturing method of the third aspect of the present invention, it is possible to further prevent the thread fraying at the sewn end portion, so that the play amount of the thread end at the end portion can be reduced. .

[Brief description of drawings]

FIG. 1 is a partially cutaway plan view of a driver airbag (1) according to an embodiment of the present invention.

FIG. 2 is a plan view of the inflator side cloth (2) before forming the mounting hole (4) and the vent hole (5) in the embodiment.

3A and 3B are views for explaining a method of forming a vent hole (5) in the embodiment, where (a) is a plan view after the sewing and (b) is a plan view after the drilling.

4A and 4B are views for explaining a method of forming a vent hole 5 according to another embodiment, wherein FIG. 4A is a plan view after sewing and FIG. 4B is a plan view after punching. is there.

FIG. 5 is a plan view of a mounting hole (4) in yet another embodiment.

FIG. 6 is a plan view of an airbag (100) in a conventional manufacturing method.

[Explanation of symbols]

 (1) …… Airbag for driver seat (2) …… Inflator side cloth (3) …… Passenger side cloth (4) …… Mounting hole (5) …… Vent hole (6) (7) …… Reinforcement cloth (8) (9) ...... Sewing (41) (51) …… Expected drilling area (81) (91) …… Sewing start point (86) (96) …… End stitch overlapped part

Claims (3)

[Claims] 1. A method of manufacturing an airbag for a vehicle, wherein a hole is provided at a predetermined position of a base fabric forming an airbag, and sewing is performed around the hole, wherein the sewing is performed in a region to be punched. A method for manufacturing a vehicle airbag, comprising: starting from the inside so as to surround an outer periphery of the region, and then punching the region after the sewing. 2. A vehicle airbag in which a base cloth constituting an airbag has holes at predetermined positions, and a reinforcing cloth for reinforcing the holes is sewn to the base cloth by sewing around the outer periphery of the holes. In the manufacturing method of the vehicle airbag, the sewing is started from within a region in which the hole is to be drilled so as to surround the outer periphery of the region, and the region is perforated after the sewing. Production method. 3. The method for manufacturing an airbag for a vehicle according to claim 1, wherein an outer peripheral portion of the perforated region is provided with a seam line overlapping portion to terminate the sewing.