JP2008194218A - Sewing apparatus and manufacturing method of air bag using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a sewing apparatus without requiring a special pretreatment step and capable of executing a highly precise sewing within a prescribed tolerance using extremely simple apparatus and a method, and a manufacturing method of air bags using the same. <P>SOLUTION: The sewing apparatus for sewing a part on a joining part or near the joining part of two base fabrics joined via an adhesive sealing material, includes sewing means, detection means installed at a prescribed position relative to a planned sewing line and detecting the end part of the joining part, and control means for stopping the sewing, when the detection means detects the end of the joining part, and the manufacturing method of air bags using the same is provided. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

The present invention relates to a sewing device and an airbag manufacturing method using the sewing device, and more particularly, to a sewing device capable of performing high-precision stitching within a predetermined tolerance and an airbag manufacturing method using the sewing device.

It has been a long time since an airbag for a frontal collision such as a driver airbag, a passenger airbag, and a rear airbag has been installed as a vehicle airbag. In recent years, the use of side airbags and curtain shield airbags corresponding to side collisions has increased. Among these, curtain shield airbags corresponding to vehicle rollovers are attracting attention. In order to absorb the impact on the head of the occupant during a few seconds while the vehicle rolls over, this airbag is required to maintain internal pressure for a long time compared to an airbag corresponding to a frontal collision. .
Further, since this curtain shield airbag has a considerably longer sewing distance than other airbags, it is also required to maintain stable sewing dimensional accuracy. In other airbags as well, it is further required to increase the seam dimension accuracy of the outer periphery sewing and the reinforcing cloth sewing.

  A method of sewing an airbag with such a high seam allowance dimensional accuracy is disclosed in Patent Document 1. This method draws a colored sewing line with a light reflectance different from that of the sheet surface on the planned sewing line on the surface of the sheet, applies spot light to the vicinity of the sewing needle insertion part on the sheet surface during sewing, and detects it with an optical sensor. The operation of the sewing machine is controlled by changing the reflected light of the spot light. In this method, it is necessary to draw a sewing line that is not originally required in terms of performance in the preceding process, which becomes a factor of increasing the cost of the airbag.

  Further, the sewing is disclosed in Patent Document 2. This sewing machine is provided on the side of the needle drop position and includes a positioning member that can position the sewing product by abutting the end of the sewing product. Provided with a cutting member which is arranged with an interval of and can cut the sewing object. This makes it possible to maintain a desired seam allowance, but it is not possible to maintain the originally required sewing shape.

  In Patent Document 3, when sewing each piece of cloth with sewing means, the two pieces of cloth to be stitched are clamped while being moved in a predetermined direction, and the cloths are sewn at least immediately before the needle drop portion where the sewing is performed. By a cloth moving means for detecting a positional deviation of the outer peripheral edge in the vicinity of the stitched portion of the piece, and for moving the cloth piece in a direction substantially perpendicular to the stitching direction based on a detection signal of the detecting means. The cloth pieces are sewn while aligning the outer peripheral edge portions thereof, and the respective cloth pieces are sewn using the ones that are not formed with stitch marks when the cloth pieces are stitched together. A manufacturing method is disclosed. However, this method complicates the equipment, and it is not possible to sew a portion where the end surfaces are not aligned, such as a reinforcing cloth.

In Patent Document 4, the work cloth is guided so that the distance between the cloth feed direction line and the side edge of the work cloth is different from the distance from the side edge of the work cloth based on the first guiding means. Therefore, the second guide means arranged in proximity to the first guide means and the actual stitch formation position in relation to the stitch formation start position or the shape of the work cloth side edge are decoded. And a control means for selectively activating the first and second guide means in relation to the decoding result of the decoding means. However, this also has a problem that the equipment becomes complicated and expensive.

JP 2005-219654 A JP 2002-159771 A JP-A-5-221278 JP 59-67992 A

The present invention provides a sewing apparatus capable of performing high-precision sewing within a predetermined tolerance by a very simple equipment and method without requiring a special pre-process, and an air bag manufacturing method using the same. The purpose is to provide.

  As a result of intensive research to solve the above problems, a sensor for detecting the end of the joint or the edge of the base fabric is attached to the sewing device at a predetermined position, and the sensor is attached to the end of the joint or the base fabric. It has been found that the sewing operation is automatically stopped when the edge portion of the sewing machine is detected, so that the sewing can be performed with a desired tolerance.

That is, the present invention is a sewing apparatus that stitches on or near the joint portion of two base fabrics joined via an adhesive seal material, and is placed at a predetermined position with respect to the stitching means and the planned stitching line. The present invention relates to a sewing device provided with a detecting means that is installed and detects an end portion of the joint portion, and a control means that stops sewing when the detecting means detects the end portion of the joint portion.
It is preferable to provide two or more detection means.
Moreover, this invention is a manufacturing method of the airbag including the process of joining two base fabrics through an adhesive sealing material, and the process of further stitching the base fabrics on or near the joint. In the suturing step, the air bag manufacturing method in which the detecting means installed at a predetermined position with respect to the suturing planned line and detecting the end of the joint stops the suturing when the end is detected. About.
Furthermore, the present invention is a sewing device for sewing two base fabrics in the vicinity of at least one edge, and includes a sewing means and a detection means that is installed at a predetermined position with respect to a planned stitch line and detects the edge. Further, the present invention relates to a sewing apparatus including a control unit that stops sewing when the detection unit detects the edge.
It is preferable that two or more detection means are provided.

  Furthermore, the present invention is an airbag manufacturing method including a step of stitching two base fabrics in the vicinity of at least one edge portion, and is installed at a predetermined position with respect to a planned stitching line in the stitching step. In addition, the present invention relates to an airbag manufacturing method in which the detection means for detecting the edge portion stops the sewing when the edge portion is detected.

  According to the present invention, it is possible to perform highly accurate sewing within a predetermined tolerance by a very simple equipment and method without requiring a special pre-process.

  As shown in FIGS. 1 and 2, the airbag manufactured by the method of the present invention is obtained by further sewing together after bonding two base fabrics.

  In the airbag 1 shown in FIG. 1, two base fabrics 2 are joined via an adhesive seal material 11, and the joined portion 3 is stitched with a sewing thread 4. In the airbag 1 of FIG. 2, the two base fabrics 2 are joined together via the adhesive seal material 11, but stitching is performed not on the joint portion 3 but in the vicinity thereof. At this time, the position of the sewing thread 4 may be inside or outside the base fabric with respect to the joint portion 3, but is preferably outside the base fabric with respect to the joint portion in terms of the reinforcing effect of the joint portion.

  Another example of an airbag manufactured by the method of the present invention is obtained by stitching two base fabrics as shown in FIGS. 3 (a) and 3 (b). In FIG. 3A, the base fabrics 2 having the same size are overlapped with each other, and the vicinity of the edge is sewn with the sewing thread 4. In FIG. 3B, the base cloths 2a and 2b having different sizes are overlapped and stitched with the sewing thread 4 in the vicinity of the edge of the base cloth 2a.

The sewing device of the present invention used for manufacturing the airbag will be described below.
The sewing apparatus according to the present invention includes a detection unit that is installed at a predetermined position with respect to a planned sewing line and detects an end portion of a base fabric bonding unit, and a detection unit that is bonded to a normal sewing machine having a sewing unit. And a control means for stopping the sewing when the edge of the part or the edge of the base fabric is detected.
The suturing means is, for example, a sewing needle.

The detection means includes a laser light receiving part and a light emitting part, such as a reflective sensor, and identifies the state of the object by the difference in the reflectance of the laser light emitted from the light emitting part and reflected by the object. I can do it. That is, it is possible to detect the presence or absence of the sealing material, whether or not it is on the joint, whether there is no base fabric, whether one sheet, two sheets, or more. Of course, it is not necessary for one device to have a laser light receiving unit and a light emitting unit, and the same detection can be performed even if the infrared laser light emitting device is installed in the sewing machine body and the laser light receiving unit is installed in the lower part of the sewing machine. I can do it.

The detection means is installed at a predetermined position with respect to the suture line. Specifically, a laser light emitting unit is installed at a position where the laser aiming matches a determined dimensional tolerance (an allowable deviation from the stitching line), and the laser light emitted from the light emitting unit and reflected by the object is reflected. A laser receiver is installed at a position where it can receive light. The planned stitch line is a planned position of a stitched portion (seam) formed by the stitching means, and the predetermined position with respect to the planned stitch line is paraphrased as a predetermined position with respect to the stitching means. Can do.
Two or more detection means are preferably installed. If there are two or more, it is possible to detect any deviation in the left or right with respect to the sewing direction. Furthermore, it is preferable to install three or more detection means. Thereby, it can respond to more complicated sewing.

The control means controls the stop and start of the suturing, and when the detection means detects that the laser aiming position has deviated from the joint, or has deviated from the target base fabric. Programmed to stop the suturing operation.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In addition, although the case where two reflection type sensors are used as the detection means has been described, of course, the present invention is not limited to this.

FIG. 4 exemplifies a case of sewing on a joint portion (not shown) of two base fabrics joined via an adhesive seal material. The sewing apparatus includes a sewing apparatus main body 5, a sewing needle 6, two reflective sensors 7, and a sewing operation control panel 8.
When the width (w) of the adhesive seal material used is 20 mm and the tolerance (a) is ± 6 mm from the center of the adhesive seal material, that is, the center of the joint, the two reflective sensors 7 are laser beams 9 Are set so that the sighting is 4 mm on each side of the suture line 10. That is, the reflection type sensors are respectively installed so that the laser emission part is located 4 mm on the left and right of the sewing needle 6 with respect to the sewing direction. In FIG. 4, the distance between the aim of the laser beam 9 and the planned stitching line 10 is indicated by a symbol d. Thus, when sewing on the joint part of the two base fabrics joined through the adhesive seal material, the distance (d) between the laser beam aim and the planned stitch line is expressed by the formula: w / 2-a Based on this, the position of the reflective sensor can be determined.

FIG. 5A is a partial cross-sectional view of the airbag showing the aiming position of the adhesive seal material 11, the stitching line 10 and the laser beam 9 when the reflective sensor 7 is installed in this manner. For example, if the seam is shifted 6 mm to the left with respect to the sewing direction, the aiming position of one laser beam 9 is the end of the joint 3 as shown in FIG. 5B, and the sensor detects this. Suture is then stopped. Thereafter, the position of the base fabric is corrected, and the suturing operation is started again. Thereby, sewing can be performed within a predetermined tolerance.

FIG. 6 exemplifies a case where the outside of the vicinity of the joint portion of two base fabrics joined via an adhesive seal material (not shown) is sewn. The sewing apparatus similarly includes a sewing apparatus main body 5, a sewing needle 6, two reflective sensors 7, and a sewing operation control panel 8.

When the width (w) of the adhesive seal material used is 10 mm and the tolerance (a) is ± 3 mm centering on the outer side of the adhesive seal material 5 mm, the two reflective sensors 7 are laser beams 9 aiming is 2mm from the suture scheduled line 10 to the base fabric 2 inside direction _{(d 1)} and the so that 8mm _{(d 2),} i.e., left 2mm and 8mm of the needle 6 that the laser light emitting portion with respect to the sewing direction Alternatively, a reflective sensor is installed so that the right side is 2 mm and 8 mm. Note that whether the sewing needle is installed on the left or right side of the sewing needle with respect to the sewing direction depends on whether the inner direction of the base fabric is the left or right direction of the sewing needle. Then, it is the left side of the sewing needle. In this way, when the vicinity of the joint portion of the two base fabrics joined via the adhesive seal material is stitched outside, the distance (d) between the laser beam aiming and the stitching planned line is the distance from the end of the adhesive seal material. The distance from the planned stitching line is defined as b, and it is obtained by the formula: b ± a. Based on this, the position of the reflective sensor can be determined.

FIG. 7A shows a partial cross-sectional view of the airbag showing the aiming positions of the adhesive seal material 11, the suture line 10 and the laser light 9 when the reflective sensor 7 is installed in this manner. For example, if the seam is shifted by 3 mm toward the adhesive seal material, the aiming position of one laser beam 9 is the end of the joint 3 as shown in FIG. 7B, and the sensor detects this. Suture is stopped. On the other hand, when the seam has shifted 3 mm from the planned stitch line to the outside of the base fabric, the other aiming position of the laser beam 9 is the end of the joint 3 as shown in FIG. When this is detected, the suturing is stopped. Thereafter, the position of the base fabric is corrected, and the suturing operation is started again. Thereby, the distance of a junction part and a stitching part can be maintained at a fixed interval.

FIG. 8 illustrates a case where base fabrics of the same size are overlapped and the vicinity of the edge portion is stitched. The sewing apparatus similarly includes a sewing apparatus main body 5, a sewing needle 6, two reflective sensors 7, and a sewing operation control panel 8.

When the seam allowance is 30 mm from the edge of the base fabric and the tolerance is ± 10 mm centered on the planned stitching line, the two reflective sensors 7 have a laser beam 9 aiming 20 mm from the planned stitching line 10 toward the outer side of the base fabric 2 ( d ₁ ) and 40 mm (d ₂ ), that is, the reflective sensor so that the laser emission part is located at 20 mm and 40 mm on the left side of the sewing needle 6 or 20 mm and 40 mm on the right side with respect to the sewing direction. Is installed. Whether to install the sewing needle on either the left or right side of the sewing direction depends on whether the outer direction of the base fabric is on the left or right side of the sewing needle. Then, it is the right side of the sewing needle. In this way, when overlapping the base fabrics of the same size and stitching the vicinity of the edge portion, the distance (d) between the laser beam aim and the planned stitching line is the base fabric edge and the planned stitching line. Where c is the distance, and the position of the reflective sensor can be determined based on this formula: c ± a.

FIG. 9A is a partial cross-sectional view of the airbag showing the stitching line 10 and the aiming position of the laser light 9 when the reflective sensor 7 is installed in this way. For example, when the seam has shifted 10 mm to the outside of the base fabric, as shown in FIG. 9B, the aiming position of one laser beam 9 is the edge of the base fabric 2, and the sensor detects this and stitches it. Is stopped. On the other hand, if the seam has shifted 10 mm from the planned stitch line to the inside of the base fabric, the other aiming position of the laser beam 9 is the edge of the base fabric 2 as shown in FIG. When this is detected, the suturing is stopped. Thereafter, the position of the base fabric is corrected, and the suturing operation is started again. Thereby, a stable seam allowance can be maintained in the outer periphery sewing of the airbag that is normally performed.

FIG. 10 illustrates a case where the base fabrics 2a and 2b having different sizes are overlapped and the vicinity of the edge of the base fabric 2a is stitched. The sewing apparatus similarly includes a sewing apparatus main body 5, a sewing needle 6, two reflective sensors 7, and a sewing operation control panel 8.

When the seam allowance is 30 mm from the edge of the base fabric 2a and the tolerance is ± 10 mm centered on the planned stitching line, the two reflective sensors 7 have a laser beam 9 aiming 20 mm from the planned stitching line 10 toward the outer side of the base fabric 2a. Reflective type so that (d ₁ ) and 40 mm (d ₂ ), that is, the laser emission part is located 20 mm and 40 mm on the left side of the sewing needle 6 or 20 mm and 40 mm on the right side with respect to the sewing direction. Install each sensor. Note that whether the sewing needle is installed on the left or right side of the sewing needle depends on whether the outer direction of the base cloth 2a is the left or right direction of the sewing needle. 10 is the right side of the sewing needle. In this way, when the base fabrics having different sizes are overlapped and the vicinity of the edge of the small base fabric is sewn, the distance (d) between the aim of the laser beam and the planned stitch line is the edge of the small base fabric. The distance between the sewing line and the planned stitching line is c ′, and is obtained by the formula: c ′ ± a, and the position of the reflective sensor can be determined based on this.

FIG. 11A is a partial cross-sectional view of the airbag showing the planned stitching line 10 and the aiming position of the laser light 9 when the reflective sensor 7 is installed in this manner. For example, when the seam has shifted 10 mm to the outside of the base fabric 2a, the aiming position of one laser beam 9 is the edge of the base fabric 2a, as shown in FIG. 11B, and the sensor detects this. Suture is stopped. On the other hand, when the seam has shifted from the planned stitching line to the inside of the base fabric 2a by 10 mm, as shown in FIG. 11C, the other aiming position of the laser beam 9 is the edge of the base fabric 2a. The sensor detects this and the suturing is also stopped. Thereafter, the position of the base fabric is corrected, and the suturing operation is started again. Thereby, the stable seam allowance can be maintained in the reinforcement cloth sewing of the airbag normally performed.

The base fabric used in the present invention includes, for example, polyamide fibers such as nylon 6, 66 and 46, aromatic polyamide fibers (aramid fibers) represented by a copolymer of paraphenylene terephthalamide and aromatic ether, and the like. Polyester fibers represented by polyethylene terephthalate, wholly aromatic polyester fibers, vinylon fibers, rayon fibers, polyolefin fibers such as ultrahigh molecular weight polyethylene, polyoxymethylene fibers, sulfone fibers such as paraphenylene sulfone and polysulfone, polyether ethers Examples thereof include organic fibers such as ketone fibers, polyetherimide fibers and polyimide fibers, and inorganic fibers such as glass fibers, ceramic fibers, carbon fibers and metal fibers, and these may be used alone or in combination. Among these, polyamide fibers such as nylon 6, 66 and 46 are preferable from the comprehensive viewpoints such as strength, durability and cost.

Further, the structure may be any of a woven fabric, a knitted fabric or a non-woven fabric. For example, in the case of woven fabric, plain weave, satin weave, twill weave, panama weave, bag weave, and the like, and in the case of knitted fabric, warp knitting and circular knitting are exemplified. Among these, a woven fabric is preferable from the viewpoint of the elongation and strength of the fabric, and a plain woven fabric is more preferable.

Further, the single yarn strength of the synthetic fiber used is preferably 5.4 g / dtex or more in order to satisfy the physical characteristics as an airbag.

  The total fineness of these synthetic fibers is preferably 155 to 470 decitex. If it is less than 155 dtex, the strength of the fabric may not be maintained, and if it is greater than 470 dtex, the thickness of the base fabric may increase, and the bag storage property may deteriorate.

  In addition, the cross-sectional shape of the single fiber of these synthetic fibers is not particularly limited to round, flat, triangular, rectangular, parallelogram, hollow, star shape, etc., but in terms of productivity and cost, it has a round cross-section. Those having a flat cross section are preferred in that the thickness of the base fabric can be reduced and the bag can be easily stored.

The cover factor when the base fabric is a woven fabric is preferably 1500 to 2500. If the cover factor is less than 1500, the opening of the fabric will be large and it will be difficult to obtain the airtightness of the bag. If the cover factor is greater than 2500, the thickness of the fabric will increase, and the bag will have good storage properties. May be worse. Here, the cover factor means that the warp yarn total fineness is D ₁ dtex, the warp yarn density is N ₁ (lines / 2.54 cm), the weft total yarn fineness is D ₂ dtex, and the weft yarn density is N ₂ ( When present per 2.54 cm) represented by ^{_{(D 1 × 0.9) 1/2 ×}} N 1 + (D 2 × 0.9) 1/2 × N 2.

These fabrics may be coated with a resin or the like for the purpose of improving heat resistance and reducing air permeability.
Examples of the resin used for the coating include halogen-containing rubbers such as chloroprene rubber, high baron rubber, and fluorine rubber, silicone rubber, ethylene propylene rubber, ethylene propylene terpolymer rubber, nitrile butadiene rubber, styrene butadiene rubber, isobutylene isoprene rubber, Rubbers such as urethane rubber and acrylic rubber, and halogen-containing resins such as vinyl chloride resin, vinylidene chloride resin, chlorinated polyolefin resin and fluororesin, urethane resin, acrylic resin, ester resin, amide resin, olefin resin and silicone resin These are used, and these are used alone or in combination. Among these, a silicone resin is preferable in terms of excellent heat resistance and weather resistance.

Furthermore, it is preferable to perform a process for reducing the friction of the coating resin film for the purpose of smoothly deploying the airbag. As the treatment, specifically, a method of applying a fine powder such as talc to the coating resin film, a method of coating by coating the coating resin with a substance that reduces adhesiveness after curing, such as an organic titanium compound, And the method of providing an unevenness | corrugation to a coating resin film using an embossing apparatus etc. is mention | raise | lifted.

The adhesive seal material used in the present invention is not particularly limited as long as it is selected in consideration of adhesiveness with the base fabric. Examples thereof include silicone adhesives, polyurethane adhesives, polyamide adhesives, and nitrile rubber adhesives, and may be thermoplastic or thermosetting. These curing mechanisms include a room temperature moisture curing type, a room temperature condensation reaction type, a room temperature addition reaction type, a heat curing type, and the like. From the viewpoint of shortening the processing time, a heat curing type is preferable.

Examples of the shape of the adhesive sealing material include, but are not particularly limited to, one liquid, two liquids or three liquids, powders, films, and tapes. Of these, a liquid type or a so-called hot melt type that has fluidity when heated is preferred in that it can easily penetrate between fiber bundles or between single fibers. In addition, it is more preferable to use the same material as the coating resin because it is advantageous in terms of material cost, productivity, quality control, and the like.

  As a method for applying the adhesive sealant, a liquid one is applied by a dispenser, screen print or spray, etc., a powder one is applied through a mold, a film or tape is used. A method of cutting and sticking to a desired shape and the like can be mentioned and may be selected as appropriate.

  About the provision width | variety of an adhesive sealing material, it is preferable that it is 1.5-20 mm. If the width is smaller than 1.5 mm, there is a risk that the adhesive will be removed from the adhesive seal material when stitching on the joint, and if the width is larger than 20 mm, the joint will be bulky and the bag may be poorly stored. There is. The thickness of the adhesive seal material is preferably 0.05 to 3 mm. If the thickness is less than 0.05 mm, the airtightness of the bag may not be maintained. If the thickness exceeds 3 mm, the bag may be poorly stored.

It is the perspective view which showed a part of airbag manufactured by this invention. It is the perspective view which showed a part of other airbag manufactured by this invention. (A) And (b) is the perspective view which showed a part of other airbag manufactured by this invention. It is the schematic diagram which showed the sewing apparatus of this invention. (A) And (b) is sectional drawing of the airbag stitching | suture part for demonstrating the manufacturing method of this invention. It is the schematic diagram which showed the other sewing apparatus of this invention. (A), (b) and (c) are sectional views of an air bag stitching portion for explaining the production method of the present invention. It is the schematic diagram which showed the other sewing apparatus of this invention. (A), (b) and (c) are sectional views of an air bag stitching portion for explaining the production method of the present invention. It is the schematic diagram which showed the other sewing apparatus of this invention. (A), (b) and (c) are sectional views of an air bag stitching portion for explaining the production method of the present invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Airbag 2, 2a, 2b Base cloth 3 Joining part 4 Sewing thread 5 Sewing apparatus main body 6 Sewing needle 7 Reflection type sensor 8 Sewing operation control board 9 Laser beam 10 Stitching line 11 Adhesive sealing material

Claims (6)

A sewing device that stitches on or near a joint portion of two base fabrics joined via an adhesive seal material, and is installed at a predetermined position with respect to a stitching means and a planned stitching line. A sewing device comprising: detection means for detecting an end portion; and control means for stopping sewing when the detection means detects an end portion of a joint portion. The sewing apparatus according to claim 1, further comprising two or more detection means. A method for manufacturing an airbag, comprising: a step of joining two base fabrics via an adhesive seal material; and a step of stitching the base fabrics on or near the joint portion. The method of manufacturing an airbag according to claim 1, wherein the detecting means that is installed at a predetermined position with respect to the suture line and detects the end portion of the joint portion stops the suturing when the end portion is detected. A sewing device that stitches two base fabrics in the vicinity of at least one edge, the stitching means, a detection means that is installed at a predetermined position with respect to a planned stitch line, and detects the edge, and the detection means A sewing apparatus provided with a control means for stopping sewing when the edge is detected. The sewing apparatus according to claim 4, comprising two or more detection means. A method of manufacturing an airbag including a step of stitching two base fabrics in the vicinity of at least one edge, wherein the edge is detected at a predetermined position with respect to a planned stitching line in the stitching step. A method for manufacturing an airbag, wherein the detection means stops the stitching when the end portion is detected.

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