JPH0481342A - Manufacture of air bag - Google Patents

Abstract

PURPOSE:To reduce width of a sealant or a tape by detecting a position of a thread different in color tone by means of an optical sensor so as to control work in a process wherein a sealant or a tape is applied to a thread which has sewn two sheets of air bag base fabric together at their outside circumferential edges. CONSTITUTION:In manufacturing of an air bag, two sheets of disc-like air bag base fabric 1, 1, are sewn together with sewing threads 2, 2, at their outside circumferential edges in such a manner that the threads 2, 2, different in color tone from the air bag base fabric 1, 1, draw a true circle each to manufacture an air bag 3. Then, the air bag base fabric 1, 1, are placed on the table 8 in such a way that a center of the threads 2, 2, each drawing a true circle coincides with a turning center of a turn tale 8. Thereafter, a position of the threads in the radial direction is detected by an optical sensor 9 while the turn table 8 is being turned. Based on the result thereof, a relative position of the turn table 8 to a sealant applying device 10 is controlled so that the position of the threads 2, 2, is always in coincidence with a central position in the width direction of a sealant 11 delivered from the sealant applying device 10 so as to perform sealing.

Description

[Detailed Description of the Invention] <Industrial Application Field> This invention relates to a method for manufacturing an airbag. Specifically, the outer peripheral edges of two airbag base fabrics are sewn together with a sewing thread, and a sealant is applied around this thread. The present invention also relates to a method of manufacturing an airbag in which a tape is applied to seal the airbag.

<Prior Art> Generally, in a part of the process of manufacturing an airbag, the outer edges of two disc-shaped airbag base fabrics are sewn together with sewing thread so that the sewing thread draws a perfect circle, and then the Place the airbag base fabric on the turntable by aligning the center of the circular thread with the center of rotation of the turntable, then rotate the turntable and place the thread above the thread. - A sealant is discharged onto the thread from a sealant application device in which a sealant discharge port is located, or a tape is supplied onto the thread from a tape pasting device in which a tape supply port is located above the thread. We are making a stop.

Conventionally, in the above manufacturing process, sealant is discharged from a sealant discharge port of a sealant applicator that is fixed at a predetermined position relative to the turntable, or the sealant is also fixed at a predetermined position relative to the turntable. This was done by supplying the tape from the tape supply port of the taping device.

However, in general, when the airbag base fabric placed on the turntable is rotating, the center position of the thread drawing a perfect circle is always aligned with the rotational center position of the turntable. The fabric does not necessarily rotate, and the threads tend to shift in the radial direction. For this reason, in conventional manufacturing processes, the width of the sealant or the width of the tape has been set large in advance in consideration of such deviation of the thread in the radial direction. For example, the width of the sealant or tape is approximately 24mm
, the weight was about 13g.

<Problems to be Solved by the Invention> However, a large width of the sealant or tape is undesirable because it increases the inertial weight of the airbag and makes the folding operation of the airbag difficult. Focusing on the above-mentioned problems, it is an object of the present invention to provide a method for manufacturing an airbag that reduces the width of the sealant or tape, reduces the inertial weight of the airbag, and facilitates the airbag folding operation. .

Means for Solving the Problem> In order to solve this problem, the method for manufacturing an airbag according to the present invention is to fabricate two disk-shaped pieces so that the sewing thread of a different color than the base fabric for the airbag draws a perfect circle. A sewing step in which the outer peripheral edge of the airbag base fabric is sewn with the sewing thread, and then the airbag base fabric is sewn so as to match the rotation center position of the turntable, which is the center position of the thread drawing the perfect circle. Next, the turntable is rotated and the radial position of the thread is detected by an optical sensor, and based on the detection result, the position of the thread is determined by applying the sealant. The relative position of the turntable and the sealant applicator is controlled so as to always match the center position in the width direction of the sealant discharged from the device, or the thread is adjusted based on the detection result by the optical sensor. so that the position always matches the center position in the width direction of the tape supplied from the tape applicator.
The present invention is characterized by comprising each step of a sealing step of controlling the relative position of the turntable and the tape applying device.

<Operations and Effects of the Invention> In the present invention, in the step of applying a sealant or pasting tape to the threads of two airbag base fabrics sewn together at the outer periphery, the optical sensor detects that the airbag base fabric is different from the airbag base fabric. The turntable and sealant applicator are designed to detect the position of the above-mentioned threads with different color tones, and to ensure that the widthwise center position of the sealant to be applied or the supplied tape always matches the detected position of the thread. Or control the relative position with the tape jam device.

Therefore, even if the center position of the perfect circle drawn by the thread sewn to the airbag base fabric deviates from the rotation center position of the turntable and the thread shifts in the radial direction, the thread The sealant is applied or the tape is supplied following the displacement in the radial direction, and even if the width of the sealant or tape is reduced, the sealant is applied or the tape is applied to the thread reliably. This makes it possible to reduce the weight of the sealant or tape, reduce the inertial weight of the airbag, and simplify the airbag folding operation.

<Example> Hereinafter, the main steps of a method for manufacturing an airbag that is an example of the present invention will be sequentially explained with reference to the drawings.

(1) Sewing process Two disk-shaped airbag base fabrics 1.
Sew the outer edge of 1 with sewing thread 2.2. This sewing process is performed using a sewing machine, as in the past.

Through this sewing process, an airbag 3 as shown in FIG. 3 in a plan view and in FIG. 4 as a sectional view taken along the line rV-IV shown in FIG. 3 is manufactured. Here, the color of the airbag base fabric 1.1 is, for example, black, and the color of the sewing thread 22 is, for example, white or yellow.

In the airbag 3 shown in Figure 3.4, the inner surface of the airbag base fabric 1, ■ appears as the outer surface, but the airbag as a final product is the airbag 3 shown in Figure 3.4. The inner and outer surfaces of the object were turned inside out. Further, in Fig. 3.4, reference numeral 4 represents an opening for installing the inflator, 5 represents a reinforcing sheet, 6 represents a hole for bolt installation, and 7 represents a vent hole.

(2) Placement process Next, align the center position of the thread 2.2 drawing the perfect circle with the rotation center position of the turntable 8, and place the airbag base fabric l, 1 on the turntable 8. Place it.

(3) Sealing process ■First embodiment of the filling process Next, the turntable 8 is rotated, and the thread 2.
The radial position of the thread 2.2 is detected by the optical sensor 9, and based on this detection result, the position of the thread 2.2 is always aligned with the center position in the width direction of the sealant 11 discharged from the sealant application device 10. Sealing is performed while controlling the relative positions of the turntable 8 and the sealant application device 10. This sealing is performed for each of the - airbag base fabric 1 and the other airbag base fabrics 1.

Here, the turntable drive mechanism 12 that rotationally drives the turntable 8 is constructed by connecting a rotation shaft 15 of the turntable 8 to a motor 13 via a deceleration mechanism 14, as shown in FIG. 1.2. be done. The rotation speed of the turntable 8 is variable, for example, from 0.15 to 2 rpm.

The sealant application device 10 uses an extrusion method to apply a sealant 11 made of RTV silicone resin or rubber glue, etc.
The sealant is configured to be discharged from the sealant discharge port 16 at the tip,
The sealant discharge port 16 is arranged above the thread 22 of the airbag base fabric 1.1 on the turntable 8.

A position control means 17 that controls the relative position between the turntable 8 and the sealant applicator 10 includes a thread detection section 18, a thread detection section horizontal movement mechanism 19, and a sealant application device vertical movement mechanism 2.
0, sealant applicator horizontal movement mechanism 21, and control circuit 22
It consists of.

The yarn detection unit 18 incorporates an optical sensor 9 arranged above the turntable 8, and the optical sensor 9 detects the radial/radial position of the yarn 2.2 when the turntable 80 rotates. The optical sensor 9 is configured to be able to detect a plurality of positions, for example, four positions, in the radial direction of the turntable 8.

The yarn detection unit horizontal movement mechanism 19 is composed of a cylinder 23 and the like, and moves the yarn detection unit 18 toward the rotation center position of the turntable 8 so that the optical sensor 9 is positioned above the yarn 2.2 immediately before the start of sealant application. Immediately after the application of the sealant is completed, the yarn detection section 18 is horizontally moved away from the rotation center position of the turntable 8.

The sealant applicator vertical movement mechanism 20 is composed of a motor 24, guide shafts 25, 25, etc., and moves the sealant applicator 10 downward just before starting sealant application to bring the sealant discharge port 16 close to the turntable 8. Immediately after the sealant application is completed, the sealant application device 10 is moved upward to move the sealant application device 10 away from the turntable 8.

The sealant applicator horizontal movement mechanism 21 includes a servo motor 26, a ball screw 27, an arm 28, gears 29, 29,
It consists of a belt 30, guide shafts 31, 31, etc.
The sealant applicator 10 is configured to move horizontally based on a control signal from the control circuit 22 when applying the sealant so that the sealant discharge port 16 is always located above the thread 2.2.

The control circuit 22 is configured to output a control signal to the sealant applicator horizontal movement mechanism 21 to constantly position the sealant discharge port 16 above the thread 22 based on the output signal of the optical sensor 9 during sealant application. has been done.

With the above-mentioned markings, the plan view is shown in Fig. 5, and the 6th
An airbag 32 as shown in FIG. 5 as a sectional view taken along the line Vl-VI in FIG. 5 is manufactured.

As shown in FIG. 7, the yarn detection section 18 is assembled integrally with the sealant application device 10, and the yarn detection section 18 is installed under the central optical sensor 9b among the three optical sensors 9a, 9b, and 9C. The radial position of the sealing material discharge port 16 may be controlled so that the sealing material discharge port 16 is always positioned. In this case, the yarn detection section horizontal movement mechanism 19 can be omitted.

■Second embodiment of sealing process Next, the turntable 8 is rotated, and the thread 2.
The radial position of the thread 2.2 is detected by the optical sensor 9, and based on this detection result, the position of the thread 2.2 always matches the center position in the width direction of the adhesive tape supplied from the tape pasting device 33 (Fig. 8). The seals are sealed while controlling the relative positions of the turntable 8 and the tape pasting device 33 so that the turntable 8 and the tape pasting device 33 are sealed.

This sealing is performed for each of the - airbag base fabric 1 and the other airbag base fabrics 1.

Here, the turntable drive mechanism that rotationally drives the turntable 8 is configured similarly to the turntable drive mechanism 12 in the first embodiment of the sealing process described above, and illustration thereof is omitted.

As conceptually shown in FIG. 8, the tape application device 33
Paper feed roll 36 on which release paper 35 with tape is wound in advance
, a winding roll 38 that winds up the release paper 37 of the release paper 35 with tape supplied from the paper feed roll 36, and a winding roll 38 that winds up the release paper 37 of the release paper 35 with tape supplied from the paper supply roll 36; An adhesive application device 40 that applies adhesive to a surface, and a discharge section 41 of the adhesive application device 40
a guide roller 43 that guides the adhesive tape 34 coated with adhesive by the adhesive applicator 40; It includes a presser roller 46 that presses against the bag base fabric 1, and tension rollers 44 and 45 that adjust the tension between the release paper 35 with tape and the release paper 37.

Although not shown, the position control means for controlling the relative position of the turntable 8 and the tape applying device 33 detects the radial position of the thread 2 using a thread detection section similar to that of the first embodiment. The position of the presser roller 46 in the rotation axis direction and the guide roller 43 are controlled based on control signals from the control circuit so that the widthwise position of the adhesive tape 34 always coincides with the detected position.

Note that in the sealing process, the sealant applicator 10 or the tape pasting device 33 is moved horizontally with respect to the turntable 8; however, in contrast to this, the sealant applicator 10
Alternatively, the tape application device 33 may be kept at a fixed position and the turntable 8 may be moved horizontally.

When an airbag was manufactured using the manufacturing method described above, a good seal was obtained even when the width of the sealant 11 or tape applied to the thread 2.2 was approximately 14 mm and the weight was approximately 7 g. It was confirmed that it was possible to secure the sex.

[Brief explanation of drawings]

FIG. 1 is a plan view of an apparatus for carrying out an airbag manufacturing method according to an embodiment of the present invention, FIG. 2 is a front view of the same apparatus, and FIG. 3 is a plan view of an airbag obtained by a sewing process. Figure 4 is a cross-sectional view of the same airbag taken along the line ■-■ shown in Figure 3, Figure 5 is a plan view of the airbag obtained by the sealing process, and Figure 6 is the fifth view of the same airbag. A sectional view taken along the line VI-Vl, FIG. 7 is a plan view of the main part of an apparatus for carrying out a method for manufacturing an airbag according to another embodiment, and FIG. 8 is a diagram illustrating manufacturing an airbag according to another embodiment It is a conceptual diagram of the taping device in the apparatus for implementing a method. DESCRIPTION OF SYMBOLS 1... Airbag base fabric, 2... Sewing thread (thread), 8... Turntable, 9.9a, 9b, 9cm/light sensor, 10... Sealant application device, 11... Sealing agent, 33... Tape pasting device. Patent applicant

Claims (1)

[Claims] A sewing step of sewing together the outer periphery of the two disc-shaped airbag base fabrics with the sewing thread so that the sewing thread of a different color tone from that of the airbag base fabric draws a perfect circle; , a placing step of placing the airbag base fabric on the turntable by aligning the center position of the thread drawing a perfect circle with the rotation center position of the turntable; Next, placing the airbag base fabric on the turntable; While rotating, the radial position of the thread is detected by an optical sensor, and based on the detection result, the thread position is always aligned with the center position in the width direction of the sealant discharged from the sealant applicator. The relative position between the turntable and the sealant applicator is controlled, or the position of the thread is always aligned with the center position in the width direction of the tape supplied from the tape applicator based on the detection result by the optical sensor. to match,
A method for manufacturing an airbag, comprising the following steps: a sealing step for controlling the relative position of the turntable and the tape applying device.