Manufacturing method for an airbag and manufacturing equipment for producing airbags

Abstract

Manufacturing method for an airbag (2) comprising the following steps: -feeding the airbags (2) in a fabric web (1) in a feeding device (I), -Cutting out the airbags (2) from the fabric web (1) in a cutting device (IV), -Arrangement of aids (4) influencing the inflation behavior and the inflation geometry based on markings (3) provided on the airbags (2), whereby -the markings (3) are arranged on the airbags (2) by means of a marking device (VIII) before the airbags (2) are cut out of the fabric web (1), whereby -with the marking device (VIII) different markings (3) are arranged in a fixed positional relationship to one another on each airbag (2), characterized in that -the different markings (3) are arranged simultaneously on one airbag (2), whereby -several marking devices (VIII) are provided which arrange the markings (3) simultaneously on different airbags (2).

Description

[0001] The present invention relates to a manufacturing method for an airbag having the features of the preamble of claim 1 and a manufacturing device for producing airbags having the features of the preamble of claim 5.

[0002] Airbags are generally used in vehicles to protect occupants in the event of a crash, preventing serious injury. These airbags are located at a predetermined location on the vehicle structure or in components attached to the vehicle structure, such as the steering wheel or dashboard. When activated, a gas generator instantly inflates them into a large bag that covers the vehicle structure or component, thereby preventing the occupant from impacting the vehicle structure or component in the event of a crash. Instead, the occupant falls into a soft cushion without sustaining serious injuries.

[0003] The airbag is either sewn together from two layers of fabric with a cavity in between, or made of two layers in an OPW (One Piece Woven Technology) with a cavity, whereby the cavity is inflated by the gas generator when the airbag is activated.

[0004] The fabric layers, or airbags manufactured using OPW technology, are produced in large numbers in a wide fabric web and must then be individually cut out of the wide fabric web. For this purpose, the airbags are fed into a production facility in the wide fabric web via a feeder and cut out of the fabric web using a cutting device, e.g., a laser.

[0005] Furthermore, to ensure optimal occupant restraint, the airbag must have a defined geometry when inflated and a defined inflation characteristic during inflation. This is achieved by providing aids such as section-by-section connections between the fabric layers with tear-open seams, attached tensioning straps, or anti-twist straps. These tensioning straps, tear-open seams, and anti-twist straps are attached or sewn to the fabric layers after the airbags have been cut out. For this purpose, markings are manually applied to the fabric layers of the airbags using a pen in an intermediate step. These markings are applied using a marker pen based on a model and then serve to show the further processing person where, for example, the tensioning strap should be sewn.

[0006] From the document US 5 222 932 A a manufacturing method for producing airbags is known, in which the airbags are cut out of a supplied fabric web, wherein markings are provided on the fabric web, which markings are arranged on the fabric web before cutting.

[0007] From the document DE 10 2016 015 751 A1 a device for producing gas bags is known, in which various gas bags with a different shape are cut out of a supplied fabric web.

[0008] Against this background, the object of the invention is to provide a manufacturing method and a manufacturing device which enable the airbags to be cut out of the fabric web with increased accuracy and process speed.

[0009] To achieve the object, a method having the method steps of claim 1 and a manufacturing device having the features of claim 5 are proposed. Further preferred developments of the manufacturing method according to the invention and the manufacturing device according to the invention can be found in the subclaims, the figure and the associated description.

[0010] According to claim 1, a manufacturing method comprising the following steps is proposed to solve the problem: -Feeding the airbags in a fabric web in a feeding device, -Cutting the airbags out of the fabric in a cutting device, -Arrangement of aids influencing the inflation behavior and the inflation geometry based on markings provided on the airbags, whereby -the markings are placed on the airbags by means of a marking device before the airbags are cut out of the fabric web, whereby -using the marking device, various markings are arranged in a fixed positional relationship to one another on each airbag, whereby -the different markings are arranged simultaneously on one airbag at a time, whereby -several marking devices are provided which arrange the markings on different airbags at the same time.

[0011] The advantage of the proposed manufacturing process is that the markings are applied to the airbags in a single process step while the airbags are still in the fabric web, i.e., not yet cut out of it. Using the data required to produce the fabric web with the airbags arranged therein, or the previously determined data on the positional relationship of the airbags in the fabric web, the markings can be arranged on the airbags simply by determining the position of the fabric web, as this is closely related to the position of the airbags arranged therein. A further advantage is that the airbags are fixed in position at the time the markings are arranged due to their arrangement in the fabric web. This alone simplifies the handling of the airbags, as they no longer have to be individually fixed in order to arrange the markings.Furthermore, the inventive solution allows the use of an automated marking device due to the use of available data, which, on the one hand, eliminates the error source of manual handling and, on the other hand, eliminates the need for pins, thus reducing waste. Furthermore, the use of an automated marking device also increases the process speed, and the data of the arranged markings, such as coordinates, type of marking, etc., can be reused and logged for further processing, particularly for the arrangement of the aids.

[0012] It is further proposed that the marking device is used to arrange various markings in a fixed positional relationship to one another on each airbag. The predetermined inflation characteristics and geometry in the inflated state are specifically achieved through the interaction of the aids, such as the tensioning straps and the tear seams, so that their arrangement in relation to one another is of particular importance. This arrangement of the aids is now improved by the markings being in a fixed positional relationship to one another. Furthermore, for example, the tensioning straps are attached to two different points on each airbag, the arrangement of which in relation to one another is of particular importance for the geometry of the airbag enforced by the tensioning strap, the accuracy of which is in turn improved by the markings being in a fixed positional relationship to one another.

[0013] The various markings will be placed simultaneously on each airbag, further increasing the accuracy of their positional relationship. Furthermore, this can increase the process speed.

[0014] It is further proposed that multiple marking devices be provided, which simultaneously apply the markings to different airbags. This allows the manufacturing process speed to be increased, or at least does not require a reduction in speed for the application of the markings.

[0015] The markings can be printed, lasered, or applied to the airbags using the marking device. If the markings are printed or lasered, this can be done contactlessly, for example, so that the fabric web can perform the transport movement required for production relative to the marking device, meaning it does not need to be stopped.

[0016] It is further proposed that the markings be personalized for different purposes. By customizing the markings, it is immediately apparent which aid is to be attached to them, or whether, for example, a tear seam needs to be sewn. This information contained in the marking itself can be used, for example, to simplify automated or manual application of the aid.

[0017] Furthermore, at least one of the markings can have a course representing a seam. The marking thus indicates not only the location of the seam, but also its course and extent. Depending on the seam to be sewn, it can be linearly straight or curved in various lengths.

[0018] The invention will be explained below using preferred embodiments with reference to the attached figures. Fig. 1 a manufacturing device according to the invention for carrying out a manufacturing method according to the invention.

[0019] In the Fig. 1 shows a manufacturing device according to the invention, which has a feeding device I in which a fabric web 1 with airbags 2 or fabric layers of the airbags 2 arranged therein is pulled off a large roll and placed on a guide device II in the form of a table.

[0020] A marking device VIII is provided on the guide device II, which is directed towards the fabric web 1 from above, i.e. from the viewpoint of the observer in the illustration. The airbags 2 are provided with a plurality of markings 3 by the marking device VIII, which mark the position of the fastening seam for the tensioning straps 4 that are ultimately to be fastened. The marking device VIII can be formed by a printing device such as a screen printing device, an offset printing device, an inkjet printing device or the like. Alternatively, the marking device VIII can also be formed by a laser processing device which has a low-power laser directed towards the fabric web 1, which slightly melts the fabric web 1 in the area of the airbags 2 to apply the markings 3 and may, but not necessarily, discolor it in the process.Alternatively, the marking device VIII can also be used to apply markings 3 in the form of stickers to the airbags 2. The markings 3 are applied in predetermined positions on the airbags 2 and serve to mark the locations at which the auxiliary means, such as the tensioning straps 4, anti-twist straps, tear seams, or the like, are subsequently arranged, which in turn serve to achieve a predetermined inflation characteristic and / or geometry of the airbag 2 in the inflated state.

[0021] After the markings 3 have been applied, the fabric web 1 is fed to a synchronization device III and then to a cutting device IV. In the cutting device IV, the airbags 2 are cut out of the fabric web 1, e.g., by means of a laser cutting device. The airbags 2 are then removed from the fabric web 1 in a removal device V and stacked laterally on a table VI. The auxiliary devices, in the present embodiment the tensioning straps 4, are then attached to the airbags 2 at the positions marked by the markings 3, e.g., by sewing, in a further processing station VII.

[0022] The advantage of the described manufacturing device and the described manufacturing method is that the markings 3 are applied to the airbags 2 when they are still in the fabric web 1. Since the position and orientation of the airbags 2 in the fabric web 1 are known, e.g., through the data used to produce the fabric web 1 or the detection of the data in a previous step, the markings 3 can be applied by the marking device VIII solely by knowing the position of the fabric web 1. During the application of the markings 3, the airbags 2 are fixed in position by the fabric web 1 itself, since they have not yet been cut out of it. Furthermore, the markings 3 can be applied to the airbags 2 automatically using the known data, thereby eliminating the source of human error. If, for example,If tensioning straps 4 are to be attached to the airbags 2, the position of at least two of the markings 3 relative to one another is of particular importance for the inflation characteristics, since this results from the combination of the length of the tensioning straps 4 and the position of the fastening points of the tensioning straps 4 relative to one another. Thus, due to the improved, precise arrangement of the markings 3, the inflation characteristics of the airbag 2 can also be indirectly improved with regard to compliance with a predetermined inflation characteristic.

[0023] Furthermore, the markings 3 can be applied simultaneously, so that the process time required to apply the markings and the associated extension of the throughput time of the fabric web 1 can be kept as small as possible.

[0024] The further advantage of the solution according to the invention compared to the solution known from the prior art is that the manual marking of the airbags 2 and the associated waste of used marking pens are eliminated.

[0025] The markings 3 are individualized for their purpose, i.e., they have different shapes and / or colors assigned to the aid to be attached. The markings 3 thus indicate which aid is to be attached, in which orientation, and in which position. If the aid is a tear-off seam, the marking 3 can also indicate the course and length of the seam to be applied.

[0026] The marking device VIII is arranged between the feed device I and the cutting device IV, so that the fabric web 1 passes the marking device during the transport movement from the feed device I to the cutting device IV. The markings 3 are applied in the marking device VIII without contact to the fabric web 1 moved by the marking device VIII. The movement of the fabric web 1 forms the feed movement, and the application of the markings 3 can be realized by a linear application, which is supplemented by the feed movement to form the two-dimensional shape of the markings 3.

[0027] If markings VIII are to be provided in the form of recesses or cutouts, these are preferably cut out in the form of zigzag seams to avoid straight edges. Furthermore, the zigzag shape of the edges allows for a certain degree of flexibility, which, for example, allows for the recesses to be widened.

Claims

[1] Manufacturing method for an airbag (2) comprising the following steps: -feeding the airbags (2) in a fabric web (1) in a feeding device (I), -cutting out the airbags (2) from the fabric web (1) in a cutting device (IV), -Arrangement of aids (4) influencing the inflation behavior and the inflation geometry based on markings (3) provided on the airbags (2), whereby -the markings (3) are arranged on the airbags (2) by means of a marking device (VIII) before the airbags (2) are cut out of the fabric web (1), whereby -using the marking device (VIII), various markings (3) are arranged in a fixed positional relationship to one another on each airbag (2), characterized by , that -the different markings (3) are arranged simultaneously on each airbag (2), whereby -several marking devices (VIII) are provided which arrange the markings (3) simultaneously on different airbags (2). [2] Manufacturing process according to claim 1, characterized by , that -the markings (3) are printed, lasered or arranged on the airbags (2) using the marking device (VIII) by means of adhesive markers. [3] Manufacturing process according to one of the preceding claims, characterized by , that -the markings (3) are individualised for different purposes. [4] Manufacturing process according to one of the preceding claims, characterized by , that -at least one of the markings (3) has a course representing a seam. [5] Manufacturing facility for the production of airbags (2) with -a feeding device (I) for feeding the airbags (2) in a fabric web (1), -a cutting device (IV) for cutting out the airbags (2) from the fabric web (1), wherein -a marking device (VIII) is provided for applying various markings (3) to the airbags (2), which mark the arrangement of aids (4) influencing the inflation behavior and the inflation geometry on the airbags (2), wherein -the marking device (VIII) is arranged between the feeding device (I) and the cutting device (IV), wherein -the marking device (VIII) is designed to print, laser or arrange the markings (3) on the airbags (2) by means of adhesive markers, characterized by , that -several marking devices (VIII) are provided which arrange the markings (3) simultaneously on different airbags (2). [6] Manufacturing device according to claim 5, characterized by , that -the marking devices (VIII) are designed to arrange different markings (3) in a fixed positional relationship to one another on each airbag (2).

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