Airbag, preferably OPW airbag, for a vehicle, airbag arrangement, airbag triggering device and method for triggering an airbag

Abstract

The invention relates to an airbag which is designed to be changed from an uninflated state to an inflated state by an inflation process in order to protect an occupant of a vehicle, wherein the airbag has at least two fabric layers which are connected to one another in such a way that at least a first airbag chamber and a second airbag chamber separate from the first airbag chamber are formed.According to the invention, it is provided that the fabric layers are further connected to one another in such a way that the first airbag chamber and the second airbag chamber can be moved independently of one another from their respective non-inflated state into their respective inflated state, and the first airbag chamber, starting from its non-inflated state, curves outwards during a first inflation process of the first airbag chamber and / or in the inflated state of the first airbag chamber at least in sections forms a tubular shape with an oval or circular cross-section and in this case an overlapping section, preferably an outer overlapping section, of the second airbag chamber in its non-inflated state or in its inflated state overlaps, preferably radially overlaps, with an overlapping section, preferably an inner overlapping section, of the first airbag chamber.

Description

[0001] The invention relates to an airbag, preferably an OPW airbag, for a vehicle, which is designed to protect an occupant of the vehicle, such as a motor vehicle or commercial vehicle, by an inflation process from an uninflated state, for example a folded or collapsed state, into an inflated state, for example an unfolded state, in which the airbag can achieve its protective effect for the occupant.

[0002] Furthermore, the invention relates to an airbag arrangement with such an airbag and two gas generators that can be operated or activated independently of one another.

[0003] Furthermore, the invention relates to an airbag triggering device with a control device and such an airbag arrangement as well as a method for triggering such an airbag arrangement.

[0004] Such air bags used in vehicles can be manufactured in different ways and, depending on the manufacturing method, are referred to as OPW air bags, cut & sew air bags or cut, seal & sew air bags.

[0005] OPW airbags, so-called one-piece woven airbags, are airbags woven from one piece, while cut & sew airbags or cut, seal & sew airbags are made from several pieces of fabric that are glued and then sewn together if necessary.

[0006] Such airbags are widely used in vehicle restraint systems to protect vehicle occupants from collisions with components of a vehicle structure such as a steering wheel, a dashboard, a door frame, etc.

[0007] Restraint systems in the form of airbag systems with such OPW airbags or with conventional airbags manufactured using cut & sew or cut, seal & sew processes are actively activated when necessary and are widely known as active restraint systems in vehicles such as motor vehicles.

[0008] Airbags are designed differently depending on their type and location of use. Different types of airbags are known from the state of the art, for example, driver and passenger airbags, side airbags, far-side airbags, head airbags, knee airbags, window airbags, etc.

[0009] The so-called far-side airbags, also called front-center airbags, are arranged, for example, in the driver's seat of motor vehicles on the side facing the front passenger.

[0010] Front airbags such as driver or passenger airbags, which are used for frontal impact protection, are usually installed on the steering wheel of the vehicle in front of the driver or behind the instrument panel for the other occupants (passengers) in the front seats.

[0011] In addition to frontal impact protection, airbags are also used to protect against side impacts. For example, the aforementioned side airbags, such as curtain airbags, seat-mounted side airbags, or door panel airbags, are also provided. Curtain airbags or special side airbags, in particular, are usually mounted along roof rails, i.e., the roof structure of the vehicle body, and deploy there to form an energy-absorbing structure between the head and upper torso of an occupant and the vehicle's interior components.

[0012] In the event of an accident or an impending accident, a sensor on the vehicle detects abnormal deceleration of the vehicle. For example, gas is supplied to the airbag within a few milliseconds to inflate it from a deflated state, i.e., folded or collapsed, to an inflated state. This is accomplished by a device such as a gas generator, commonly referred to as an "inflator." The inflated airbag cushions the vehicle occupant from the impact forces.

[0013] In addition to the aforementioned OPW process, airbags are often manufactured using the more complex Cut & Sew or Cut, Seal & Sew processes mentioned above.

[0014] In particular, in the cut & sew process, pieces of fabric forming the respective fabric layers are first cut into the desired shape, placed on top of each other and sewn together to form the airbag, the so-called cut & sew airbag.

[0015] Known airbags manufactured using the cut, seal, and sew process for this purpose represent complex solutions and require considerable manufacturing effort. For example, two or more identical, partially identical, or different parts are cut from a silicone-coated flat fabric, a sealant is sprayed onto the edges—e.g., in the form of a circumferential bead—and the two or more fabric parts are then superimposed, and the parts are then bonded together. Additionally, the fabric layers thus formed are provided with a seam to ensure sufficient strength of the adhesive seam.

[0016] For airbags manufactured using the cut & sew process and for airbags manufactured using the cut, seal & sew process, additional components, such as retaining straps, tabs, etc., sometimes have to be sewn on in a further process step for shaping (with or without sealant).

[0017] The Cut & Sew process and the Cut, Seal & Sew process can therefore be more time-consuming and costly than the OPW process and often require numerous manual process steps.

[0018] To increase the protective effect of airbags, one approach is being pursued, particularly in the area of ​​frontal impact protection or side impact protection (e.g., driver airbags, passenger airbags, side airbags), to design the airbags with a larger contact surface or impact area, into which an occupant impacts in the event of a vehicle collision. Previously, the state of the art has been to design airbags with a larger airbag volume for this purpose. However, larger airbag volumes require larger gas generators and thus inevitably require more installation space in the vehicle, which runs counter to the design specifications for airbags.

[0019] Due to a wide variety of influencing factors such as the size, weight, seating position of the occupant, speed of the vehicle, angle of impact of the occupant in relation to the airbag, it can be advantageous in the event of a crash or collision of the vehicle in order to achieve maximum protection for the occupant if an airbag has two or more stages in terms of its inflation height and is ignited or filled accordingly depending on the accident situation.

[0020] For this purpose, airbags with two-stage inflation heights are known from the prior art. These are inflated in two stages and whose deployment is controlled by tethers, etc. However, these can currently only be manufactured using extremely complex processes. For example, complex and expensive tether constructions are required, which are cut with a so-called pyro-cutter, for example, in the event of a collision, in order to achieve a higher inflation height in a subsequent stage or to control its progression.

[0021] Such multi-stage airbags are used, for example, in adaptive restraint systems as so-called "adaptive airbags", which can be deployed in several stages depending on the severity of the accident. Based on sensor data, for example by recording the influencing factors listed above, these "adaptive airbags" can be individually adapted to the occupant and the accident situation, i.e. such an adaptive airbag can automatically adapt both the internal pressure of the airbag and its geometry to the occupant's size and other crash variables such as impact speed and seating position in the event of an accident. This can be done, for example, on the basis of the sensor data and with the help of special retaining straps, which can be used to individually adjust the airbag shape and airbag working pressure to the respective occupant.

[0022] Known airbag designs with tethers are manufactured according to the state of the art with only one airbag chamber, with a two- or multi-stage inflation height being achieved by filling the airbag with different gas volumes. For example, to achieve a first inflation height in a first stage, the airbag is filled with a corresponding gas volume and deployment is controlled via the kinematic constraints predetermined by the tethers. To achieve a second or maximum inflation height in a second stage, the airbag is then further filled with a corresponding second gas volume, with the tethers continuing to control the further deployment of the airbag. If the maximum inflation height is to be achieved directly, the airbag is filled to its maximum in a single step. Such known two-stage airbags have so far only been manufactured at great expense using the cut & sew technology described above.

[0023] However, it is problematic to optimally match the capacity of the gas generator to a corresponding two-stage airbag. For example, it may happen that the airbag is insufficiently or excessively filled with gas during the inflation process to trigger the first or second stage, resulting in either too low or too high an internal airbag pressure, and thus the specified internal airbag pressures cannot be achieved in the first or second stage. This can significantly compromise the protective effect of the airbag in the event of a crash or collision with the vehicle.

[0024] It is therefore an object of the invention to provide an airbag, preferably an OPW airbag, an airbag arrangement, an airbag triggering device and a corresponding triggering method, with which the disadvantages known from the prior art can be at least partially avoided or at least reduced; preferably, the invention is intended to provide a multi-stage airbag that can achieve an adequate protective effect.

[0025] This object is achieved by an airbag according to claim 1, an airbag arrangement according to claim 10, an airbag triggering device according to claim 11 and a method for triggering an airbag arrangement according to claim 12.

[0026] Further advantageous embodiments and developments of the invention emerge from the dependent claims.

[0027] The airbag according to the invention is preferably a woven OPW airbag and is designed to protect a vehicle occupant by an inflation process from a non-inflated state, for example a folded or collapsed state, into an inflated state in which the airbag can exert its intended protective effect for the occupant, wherein the airbag has at least two fabric layers, preferably in some areas two fabric layers and / or in some areas three fabric layers, which are connected to one another in such a way that at least one first airbag chamber and one second airbag chamber are formed which is separate from the first airbag chamber, i.e. which is not fluidically connected to the first airbag chamber, wherein the fabric layers are further connected to one another in such a way that - the first, preferably three-layered, airbag chamber and the second, preferably two-layered or three-layered, airbag chamber can be moved independently of one another from their respective uninflated state to their respective inflated state, and - the first airbag chamber, starting from its non-inflated state, curves outwards during a first inflation process of the first airbag chamber and / or in the inflated state of the first airbag chamber at least partially forms a tubular shape with an oval or circular cross-section and in this case an overlapping section, preferably an outer overlapping section, of the second airbag chamber in its non-inflated state or in its inflated state overlaps, preferably radially overlaps, with an overlapping section, preferably an inner overlapping section, of the first airbag chamber.

[0028] According to the invention, an OPW airbag with a two-stage inflation height can thus be realized, which is preferably used as a front airbag in the vehicle.

[0029] The first stage is achieved, for example, by inflating the first airbag chamber while leaving the second airbag chamber in its deflated state. The inflation height of the airbag is thus largely determined by the inflated first airbag chamber, which has a tubular shape with an oval or circular cross-section. Although the overlapping section of the second airbag chamber overlaps the overlapping section of the first airbag chamber in this state, it does not significantly contribute to the inflation height of the airbag. The second stage is achieved, for example, by inflating both airbag chambers. Accordingly, the overlapping section of the second airbag chamber further increases the inflation height of the airbag.

[0030] The automated OPW manufacturing process eliminates the complex sewing operations required for airbags manufactured using the cut-and-sew process. The inflation heights of the different inflation stages can be manufactured with greater inflation height differences than with previously known solutions.

[0031] In other words, the airbag can be manufactured with different chamber volumes for each of the airbag chambers, which can also have significantly different filling volumes. Since the inventive design of the airbag has at least two separately fillable airbag chambers, gas generators adapted to the respective chamber volume or filling volume of the respective airbag chamber can be used, thereby generating the optimal internal pressure in each of the airbag chambers.

[0032] The use of two separate or different gas generators instead of one very large gas generator can be advantageous in terms of generator type selection, as a specific gas generator can be selected for each airbag chamber and its specific properties. This allows, for example, faster inflation times, different trigger times, and, due to the two separate gas sources, also different internal pressures in the respective airbag chambers. Furthermore, alternative installation options for the two gas generators arise, as, for example, two smaller gas generators can be used instead of one large gas generator due to their respective dimensions.

[0033] The OPW airbag overlaps with the respective overlapping sections of the first and second airbag chambers at a defined or predetermined location, whereby when a second gas generator is triggered to fill the second airbag chamber, a further inflation height or further stage of the airbag is achieved, predominantly at the predetermined location where the overlapping sections are located.

[0034] Thus, when the first stage is triggered, the airbag can have a first inflation height which is formed by a sum of a diameter of the first airbag chamber in its inflated state and the thickness of the overlapping section of the second airbag chamber in its non-inflated state.

[0035] Furthermore, upon triggering of the second stage, the airbag may have a second inflation height which is formed by a sum of a diameter of the first airbag chamber in its inflated state and the thickness of the overlapping portion of the second airbag chamber in its inflated state.

[0036] In particular, the region of the airbag at which the two overlapping sections are arranged, ie at which a section of the first airbag chamber and a section of the second airbag chamber lie on top of one another or overlap in cross-section when the first airbag chamber is inflated, forms a variable region which determines the first inflation height and the second inflation height.

[0037] In the case of a circular cross-section, the diameter of the first airbag chamber in its inflated state can be the outer diameter of the circular cross-section, the inner diameter of the circular cross-section, or an average diameter formed from the inner and outer diameters.

[0038] However, in the case of an oval or elliptical cross-section of the first airbag chamber in its inflated state, the major or minor semi-axis (of the ellipse) or a value derived therefrom can be taken into account.

[0039] The activation can be controlled depending on the accident circumstances, ie the second gas generator is only activated when necessary to fill the second airbag chamber.

[0040] The respective airbag chambers form a hollow cylinder shell and are additionally located one above the other or overlap in sections, namely at their overlapping sections, but can be filled separately or independently of one another and are therefore not connected to one another in terms of flow technology, whereby a corresponding filling pressure and a corresponding filling time can be achieved depending on the design of the respective airbag chamber and the selection of the respective gas generator.

[0041] The airbag according to the invention can be further developed such that the fabric layers are connected or woven together such that the outer overlap section of the second airbag chamber in the uninflated state radially overlaps the inner overlap section of the first airbag chamber in the inflated state and / or curves outwards during a second inflation process of the second airbag chamber or extends along the inner overlap section of the first airbag chamber in the inflated state and thereby radially overlaps the inner overlap section of the first airbag chamber in the inflated state and / or forms a radially outer tube wall section or hollow cylinder wall section with respect to the radially inner overlap section of the first airbag chamber in the inflated state.

[0042] When the airbag is fully inflated, i.e., when both the first airbag chamber and the second airbag chamber are completely filled with gas or air, the airbag is shaped like a tube with a circular or oval cross-section, with the two overlapping sections forming a wall section with a greater tube wall thickness than the remaining wall sections of the tube. The two overlapping sections are also in contact with each other.

[0043] Preferably or optionally, the overlapping sections can be connected to one another, for example sewn, namely at a point where the overlap of both overlapping sections begins and at a further point where the overlap of both overlapping sections ends.

[0044] Furthermore, the airbag according to the invention can be realized in such a way that the first airbag chamber has a plurality of (fluidically) interconnected first airbag longitudinal chambers with respective first (identical or different) airbag chamber volumes, which in the inflated state are arranged next to one another in the circumferential direction and / or extend axially, transversely, obliquely or helically, and / or the second airbag chamber has a single airbag longitudinal chamber or a plurality of (fluidically) interconnected second airbag longitudinal chambers with respective second (identical or different) airbag chamber volumes, which in the inflated state are arranged next to one another in the circumferential direction and / or extend axially, transversely,extend obliquely or helically and / or the plurality of / group of the first airbag longitudinal chambers is arranged in the circumferential direction next to the single airbag longitudinal chamber or the plurality of / group of the second airbag longitudinal chambers.,

[0045] Preferably, a depth direction of the airbag in the inflated state corresponds to an axial direction of the thus formed tube or hollow cylinder. For example, the airbag longitudinal chambers thus extend transversely, i.e., at right angles, to the depth direction or axial direction of the tube in its circumferential direction and can thus take the form of a circular ring or circular ring segment. If the airbag longitudinal chambers are parallel to the depth direction or axial direction of the tube, they run, for example, in the form of elongated tubes in the longitudinal direction of the tube / hollow cylinder and are preferably distributed or offset in the circumferential direction around the tube / hollow cylinder.

[0046] Another design for the airbag's longitudinal chambers is when they extend obliquely to the depth direction, i.e., their extension runs both axially and circumferentially. For example, a tubular chamber configured in this way takes the form of a helix, i.e., a screw line or cylindrical spiral that describes a curve that winds at a constant pitch around the shell of a cylinder, i.e., in this case, the hollow cylinder, by a certain angular dimension.

[0047] Likewise, designs of the airbag are conceivable in which the multiple longitudinal airbag chambers are arranged one behind the other in the direction of their extension, for example, longitudinal airbag chambers arranged one behind the other parallel to the depth direction or longitudinal airbag chambers arranged one behind the other transversely to the depth direction and in the circumferential direction. In this case, the respective longitudinal airbag chambers arranged one behind the other are spatially separated from one another by respective seam sections, but are fluidly connected to one another.

[0048] Furthermore, the airbag according to the invention can be designed such that the first airbag chamber volumes of the first airbag longitudinal chambers are smaller, equal to or larger than the second airbag chamber volumes of the second airbag longitudinal chambers.

[0049] Furthermore, the airbag according to the invention can be implemented such that the first airbag longitudinal chambers and / or the second airbag longitudinal chambers are tubular or, at least in sections, hollow-cylindrical or in the shape of an elliptical hollow cylinder. Tubular in the context of the first and second airbag longitudinal chambers means, among other things, that they form an elongated hollow body with any cross-section, in particular with a circular, oval, semicircular, or rectangular cross-section.

[0050] Furthermore, the airbag according to the invention can be realized in such a way that the airbag has at least in sections three fabric layers, namely a first fabric layer, a second fabric layer and a third fabric layer, wherein the second fabric layer is arranged between the first fabric layer and the third fabric layer.

[0051] Preferably, the first fabric layer forms a lower fabric layer or a fabric layer forming an inner shell of the airbag, the second fabric layer forms a middle fabric layer or a fabric layer arranged at least in sections in the interior of the airbag, and the third fabric layer forms an upper fabric layer or an outer shell of the airbag.The three fabric layers are woven together in such a way that, in an area forming the first airbag chamber, first longitudinal airbag chambers extending in the axial direction and radially offset from one another are formed between the first fabric layer and the second fabric layer and the third fabric layer and the second fabric layer and / or, in an area forming the second airbag chamber, second longitudinal airbag chambers extending in the axial direction and radially offset from one another are formed between the first fabric layer and the second fabric layer and the third fabric layer and the second fabric layer, which cause an outward curvature at least in sections during their respective inflation processes.

[0052] Furthermore, the airbag according to the invention can be implemented in such a way that the airbag has at least in sections three fabric layers, namely a lower or first fabric layer, an upper or third fabric layer and a middle or second fabric layer arranged therebetween, wherein the three fabric layers are woven together in such a way that in a region forming the first airbag chamber, first airbag longitudinal chambers extending in the axial direction and radially offset from one another are formed between the first fabric layer and the second fabric layer and the third fabric layer and the second fabric layer, while only two fabric layers in a region forming the second airbag chamber form one or more second airbag longitudinal chambers extending in the axial direction between the first fabric layer and the third fabric layer.

[0053] In addition, the airbag according to the invention can be designed in such a way that the first airbag chamber is connected to a region which forms a first generator mouth for receiving a first gas generator or a first connection region for connecting a first gas generator, and the second airbag chamber is connected to a region which forms a second generator mouth separate from the first generator mouth for receiving a second gas generator or a second connection region for connecting a second gas generator, so that the first airbag chamber and the second airbag chamber can be inflated independently of one another via the respective first or second gas generator.

[0054] Furthermore, the airbag according to the invention can be further developed in such a way that the airbag is designed as an OPW airbag with warp threads and weft threads which are woven into the woven fabric layers, wherein the warp threads and weft threads are woven together in such a way that the airbag has a first partial region and a second partial region as well as a region forming the first airbag chambers, wherein the first partial region is arranged between the region forming the first airbag chambers and the second partial region, wherein the warp threads and weft threads in the second partial region are woven together in such a way that the second partial region has at least one generator mouth for receiving a gas generator for filling the airbag or a connection for connecting a generator and is formed in two layers, wherein the warp threads and weft threads in the region forming the first airbag chambers are woven together such that the region forming the first airbag chambers has the plurality of first airbag chambers and is formed in three layers, and wherein the warp threads and weft threads of the second fabric layer emerge from the second fabric layer in the first partial area and float completely between the first fabric layer and the third fabric layer and are integrated into the first fabric layer and / or the third fabric layer in the second partial area.

[0055] Thus, the first fabric layer and third fabric layer in the second partial area have the warp threads and weft threads of the second fabric layer.

[0056] In an alternative embodiment, the warp and weft threads are woven differently from the embodiment described above, particularly in the first and second partial areas.

[0057] According to the alternative variant, the weft threads of the middle fabric layer emerge from the middle fabric layer in the first sub-area of ​​the airbag and are partially attached to the upper fabric layer and partially to the lower fabric layer, whereas the warp threads of the middle fabric layer emerge from the middle fabric layer in the first sub-area of ​​the airbag and float freely between the lower fabric layer and the upper fabric layer. In the second sub-area, the weft threads and warp threads of the middle fabric layer are bound into the lower fabric layer or the upper fabric layer, or are attached to the lower fabric layer or the upper fabric layer at a few attachment points.

[0058] Of course, in principle the warp and weft directions and thus also the warp and weft threads can be swapped in both versions.

[0059] The airbag arrangement according to the invention comprises the above-mentioned airbag according to the invention and at least two independently activatable gas generators, wherein a first generator of the two gas generators is accommodated or connected in the first generator mouth or the first connection area of ​​the first airbag chamber and a second generator of the two gas generators is accommodated or connected in the second generator mouth or the second connection area of ​​the second airbag chamber.

[0060] Preferably, the two gas generators are different gas generators, which are matched to the respective first and second airbag chambers with regard to their filling behavior (e.g., with regard to the deliverable gas volume flow) or are matched to the respective first and second airbag chamber volumes. As a result, the properties and advantages explained in connection with the airbag according to the invention also apply to the airbag arrangement according to the invention in the same or similar manner. Therefore, to avoid repetition, reference is made to the corresponding explanations in connection with the airbag according to the invention.

[0061] The airbag triggering device according to the invention for triggering an airbag has a control device and the airbag arrangement according to the invention, wherein the control device is configured to activate the first generator to fill the first airbag chamber and is further configured to activate the second generator to fill the second airbag chamber when the first generator has already been activated and a predetermined condition is met, preferably a predetermined time has elapsed. As a result, the properties and advantages explained in connection with the airbag according to the invention also result in the same or similar way for the airbag triggering device according to the invention, which is why, to avoid repetition, reference is made to the corresponding explanations in connection with the airbag according to the invention.

[0062] The method according to the invention for triggering the airbag arrangement according to the invention comprises the following steps: Activating the first generator to fill the first airbag chamber of the airbag, and Activating the second generator to fill the second airbag chamber of the airbag, simultaneously or after the first generator has already been activated. This results in the properties and advantages explained in connection with the airbag according to the invention also being applied to the method according to the invention in the same or similar manner. Therefore, to avoid repetition, reference is made to the corresponding explanations in connection with the airbag according to the invention.

[0063] Preferred embodiments of the invention are explained below by way of example with reference to the figures.

[0064] They show: Fig. 1a) a schematic representation of an airbag according to the invention according to a first embodiment in a cross-sectional view in a state in which a first airbag chamber is inflated and a second airbag chamber is not inflated; Fig. 1b) a schematic representation of the airbag according to the invention of Fig. 1a) in a cross-sectional view in a state in which both the first airbag chamber is inflated and the second airbag chamber is inflated; Fig. 2) a schematic representation of the airbag according to the invention of Fig. 1 a) in the laid out or spread out state in a plan view; Fig. 3a) a schematic representation of an airbag according to the invention according to a second embodiment in a cross-sectional view in a state in which the first airbag chamber is inflated and the second airbag chamber is inflated with only a single second airbag longitudinal chamber; Fig. 3b) a schematic representation of the airbag according to the invention of Fig. 3a) in the laid out or spread out state in a plan view; Fig. 4a) a schematic representation of an airbag according to the invention according to a third embodiment in a cross-sectional view in a state in which the first airbag chamber is inflated and the second airbag chamber with two second airbag longitudinal chambers is inflated; Fig. 4b) a schematic representation of the airbag according to the invention of Fig. 4a) in the laid out or spread out state in a plan view; Fig. 5a) a schematic representation of an airbag according to the invention according to a fourth embodiment in a cross-sectional view in a state in which the first airbag chamber is inflated and the second airbag chamber with a plurality of second airbag longitudinal chambers is inflated; Fig. 5b) a schematic representation of the airbag according to the invention of Fig. 5a) in the laid out or spread out state in a top view.

[0065] The airbag or gas bag or airbag 10 according to the invention is in the Fig. 1-5 is manufactured as an OPW airbag, ie a so-called “one-piece woven” airbag 10, an airbag 10 woven in one piece.

[0066] In this specific application, the airbag 10 is designed as a front airbag in this exemplary embodiment and is accordingly provided behind an instrument panel (not shown in detail) in front of the passenger in a conventional manner not described in detail here. Alternatively, the airbag 10 according to the invention can also be used, for example, as occupant protection in the field of autonomous driving.

[0067] The airbag 10 according to the invention is designed to protect an occupant of a vehicle, such as a motor vehicle or commercial vehicle, in a conventional manner by means of an inflation process from a non-inflated state, such as a folded or collapsed state, to an inflated state in which the airbag can exert its protective effect on the occupant. This means that the airbag 10 is deployed from the non-inflated state to the inflated state in a conventional manner in response to activation of an inflation device (not shown in the figures), which in this case has two gas generators, which are activated, for example, upon detection of a vehicle collision or the like.

[0068] As in the Fig. 1 and Fig. 2 is only schematically shown, the airbag 10 has for this purpose several fabric layers 11, 12, 13 which are explained in more detail below, wherein in one or more areas of the airbag 10 two fabric layers lie on top of each other and in one or more areas three fabric layers lie on top of each other, which will be explained in more detail later.

[0069] The fabric layers 11, 12, 13 are connected to one another in such a way that in this case a first airbag chamber 14 (in detail first airbag longitudinal chambers 14 1 , 14 2 , 14 3 ) and a second airbag chamber 24 separate from the first airbag chamber 14 (in detail second airbag longitudinal chambers 24 1 , 24 2 , 24 3 , 24 4 ). The first airbag chamber 14 and the second airbag chamber 24 are not fluidically connected to each other.

[0070] In other words, the airbag 10 is designed as an OPW airbag with warp threads running in the warp direction K and weft threads running in the weft direction S (see for example Fig. 2 - warp and weft directions can alternatively also be reversed) which are woven into the woven fabric layers 11, 12, 13 to form the first airbag chamber 14 and the second airbag chamber 24, wherein a woven seam 22, in which the woven fabric layers 11, 12, 13 are combined into one layer, separates the first airbag chamber 14 and the second airbag chamber 24 from each other. Accordingly, the airbag 10 has independently fillable first and second airbag chambers 14, 24.

[0071] In this context, the fabric layers 11, 12, 13 are further connected to one another in such a way that the first airbag chamber 14 is designed in three layers and the second airbag chamber 24 is preferably designed in two layers or alternatively in three layers, wherein the first and second airbag chambers 14, 24 can be moved independently of one another from their respective non-inflated state to their respective inflated state.

[0072] Furthermore, the fabric layers 11, 12, 13 are connected to one another in such a way that the first airbag chamber 14, starting from its non-inflated state, curves outwards during a first inflation process of the first airbag chamber 14 and then, in the inflated state of the first airbag chamber 14, at least partially forms a tubular shape or hollow cylindrical shape with a substantially circular or oval cross-section.

[0073] An outer overlap section ÜA overlaps außenthe second airbag chamber 24 in its non-inflated state or in its inflated state with an inner overlap section ÜA innen the first airbag chamber 14 in the radial direction, as shown in particular in Fig. 1 is recognizable.

[0074] Fig. 1a) shows a schematic representation of the airbag 10 according to the invention according to the first embodiment in a cross-sectional view in a state in which the first airbag chamber 14 is inflated and the second airbag chamber 24 is not inflated, whereas Fig. 1b) a schematic representation of the airbag 10 according to the invention of Fig. 1a) in a cross-sectional view in a state in which both the first airbag chamber 14 and the second airbag chamber 24 are inflated. Furthermore, Fig. 2) a schematic representation of the airbag 10 according to the invention of Fig. 1 a) in the laid out or spread out state in a top view.

[0075] How to continue in the Fig. 1 and Fig. 2, the outer overlap section ÜA außen the second airbag chamber 24 in the non-inflated state with the inner overlap section ÜA innen the first airbag chamber 14 in the inflated state radially ( Fig. 1 a)). Furthermore, the outer overlap section ÜA curves außen during a second inflation process of the second airbag chamber 24 outwards and extends along the inner overlap section ÜA innen the first airbag chamber 14 in the inflated state and overlaps with the inner overlap section ÜA innen of the first airbag chamber 14 in the inflated state. As a result, the outer overlap section ÜA außena radially outer tube wall section or hollow cylinder wall section with respect to the radially inner overlap section ÜA innen the first airbag chamber 14 in the inflated state.

[0076] As in Fig. 1 and is indicated by an arrow, the overlapping sections ÜA innen and ÜA außen defined as an area in which the first airbag chamber 14 and the second airbag chamber 16 overlap in the radial direction along the circumferential direction of the airbag.

[0077] As continues to be the case, in particular Fig. 1a) and Fig. 1b), the first airbag chamber 14 has a plurality of first airbag longitudinal chambers 14 which are fluidically interconnected. 1 , 14 2 , 14 3with respective first airbag chamber volumes which, in the inflated state, are arranged circumferentially next to one another and extend axially.

[0078] In addition, the second airbag chamber 24 in this case has a plurality of interconnected second airbag longitudinal chambers 24 1 , 24 2 , 24 3 , 24 4 with respective second airbag chamber volumes which, in the inflated state, are arranged circumferentially next to one another and extend axially.

[0079] Moreover, in the Fig. 1a) and Fig. 1b) it can be seen that the plurality of or group of the first airbag longitudinal chambers 14 1 , 14 2 , 14 3 in the circumferential direction next to the plurality of or group of the second airbag longitudinal chambers 24 1 , 24 2 , 24 3 , 24 4The respective first airbag chamber volumes of the first airbag longitudinal chambers 14 1 , 14 2 , 14 3 In this embodiment, with the same longitudinal extension (warp direction in Fig. 2) smaller than the respective second airbag chamber volumes of the second airbag longitudinal chambers 24 1 , 24 2 , 24 3 , 24 4 trained.

[0080] Furthermore, from the Fig. 1a) and Fig. 1b shows that the first airbag longitudinal chambers 14 1 , 14 2 , 14 3 and the second airbag longitudinal chambers 24 1 , 24 2 , 24 3 , 24 4 are essentially hollow cylindrical or in the shape of an elliptical hollow cylinder.

[0081] In the Fig. 2) it can be seen that the airbag 10 in this state, ie with the fabric layers lying on top of one another, has a substantially rectangular shape which substantially corresponds to the outer surface of the hollow cylinder, the area with the first airbag chamber 14 is adjoined by an area with a first generator mouth 18 for receiving a first gas generator (not shown here), and the area of ​​the second airbag chamber 24 is adjoined by an area with a second generator mouth 20, separate from the first generator mouth 18, for receiving a second gas generator (not shown here), so that the first airbag chamber 14 and the second airbag chamber 24 can be inflated independently of one another via the respective first or second gas generator.

[0082] Together with two independently activatable gas generators (not shown here), the airbag 10 forms an airbag arrangement according to the invention, wherein a first generator of the two gas generators is accommodated in the first generator opening 18 and a second generator of the two gas generators is accommodated in the second generator opening 20. The respective generators are designed differently with regard to their filling behavior. Thus, the first generator connected to the generator opening 18 can generate a larger volume flow than the second generator connected to the generator opening 20 if the first airbag chamber 14 has a larger volume than the second airbag chamber 24.

[0083] To activate the generators, a control device (not shown) is provided next to the airbag arrangement, which together form an airbag triggering device configured to trigger the airbag 10. The control device (not shown in this case) is configured to activate the first generator to fill the first air chamber 14 and is further configured to activate the second generator to fill the second air chamber 24 if the first generator has already been activated and a predetermined condition is met, which in this case is the elapse of a predetermined time. Likewise, the control device can also activate both generators simultaneously, if necessary.

[0084] Accordingly, the operation of the airbag arrangement, namely the triggering of the airbag arrangement, is as follows: First, the first generator is activated to fill the first air chamber 14 of the airbag 10, whereby the first airbag longitudinal chambers 14 1 , 14 2 , 14 3 into their inflated state and thus the first stage of the inflation height of the airbag 10 is reached.

[0085] Subsequently, ie after a predetermined time has elapsed, or simultaneously, depending on the type of vehicle collision, for example the extent of the detected acceleration values, the second generator is activated to fill the second air chamber 24 of the airbag 10. This also fills the outer overlap section ÜA außen the second airbag chamber 24 is filled, whereby the air in the outer overlap section ÜA außen arranged second airbag longitudinal chambers 24 1 , 24 2 , 24 3 , 24 4into their inflated state and thereby the second stage of the inflation height of the airbag 10 is achieved.

[0086] The basic structure of the airbag 10 has been described above.

[0087] In order to form the aforementioned chamber structure from the first airbag chamber 14 with its first airbag longitudinal chambers 14 1 , 14 2 , 14 3 and the second airbag chamber 24 with its second airbag longitudinal chambers 24 1 , 24 2 , 24 3 , 24 4 In order to achieve this, the airbag 10 is constructed from the aforementioned superimposed fabric layers 11, 12, 13, which are specifically woven into three fabric layers in an area LKB of the airbag 10 forming the first airbag chamber 14 and can be woven into two or three fabric layers in a further area forming the second airbag chamber 24.

[0088] The concrete structure of the airbag 10 with regard to the chamber structure achieved by weaving the respective fabric layers is explained in more detail using the embodiments described below.

[0089] Fig. 3a) shows a schematic representation of an airbag 10 according to the invention according to a second embodiment in a cross-sectional view in a state in which the first airbag chamber 14, 16 with a plurality of airbag longitudinal chambers is at least partially inflated and the second airbag chamber 24 with a single airbag longitudinal chamber is at least partially inflated. Fig. 3b) shows a schematic representation of the airbag 10 according to the invention of Fig. 3a) in the laid out or spread out state in a top view.

[0090] As can be seen from the Fig. 3a) and Fig. 3b), the airbag 10 has three fabric layers 11, 12, 13 in the area LKB forming the first airbag chamber 14, namely a lower or first fabric layer 11, an upper or third fabric layer 13 and a middle or second fabric layer 12 arranged therebetween, wherein the three fabric layers 11, 12, 13 are woven together in such a way that in the area LKB forming the first airbag chamber 14, the first airbag longitudinal chambers 14 extending in the axial direction and arranged next to one another in the circumferential direction 1 , 14 2 , 14 3 and 16 1 , 16 2 ,..., 16 8 In particular, the first (inner) airbag longitudinal chambers 16 are formed between the lower / inner fabric layer 11 and the middle fabric layer 12. 1 , 16 2 ,..., 16 8 formed and between the upper / outer fabric layer 13 and the middle fabric layer 12 the first (outer) airbag longitudinal chambers 14 1 , 142 , 14 3 , 14 BK ,... formed.

[0091] As continues from Fig. As can be seen in Figure 3a, the first (inner) airbag longitudinal chambers 16 1 , 16 2 ,..., 16 8 radially to the first (outer) airbag longitudinal chambers 14 1 , 14 2 , 14 3 , 14 BK ,... offset, ie offset radially further inwards. In this embodiment, three of the first (outer) airbag longitudinal chambers 14 1 , 14 2 , 14 3 each from one of the first (outer) airbag longitudinal chambers 14 1 , 14 2 , 14 3 , 14 BK radially covered, whereby a respective first (outer) airbag longitudinal chamber 14 BK (also called airbag longitudinal bridge chamber) two adjacent of the first (inner) airbag longitudinal chambers 16 1 , 16 2 ,..., in the circumferential direction.

[0092] Based on this chamber structure of the first inner and outer airbag longitudinal chambers 14 1 , 14 2 , 14 3 and 16 1 , 16 2 ,..., 16 8 a very stiff and stable outwardly curved structure of the airbag 10 is created in the inflated state, which forms a hollow cylinder or tube with an almost circular or oval hollow cylinder cross-section.

[0093] As continued in Fig. 3a), the fabric layers 11, 12, 13 are woven into a single woven seam WN in an intermediate region between the region LKB forming the first airbag chamber 14, 16 and the region forming the second airbag chamber 24, which in the region forming the second airbag chamber 24 again merges into two fabric layers 11 and 13, a lower / inner fabric layer 11 and an upper / outer fabric layer 13, which are woven together such that in the region forming the second airbag chamber 24, the second airbag chamber 24 forms a single, axially extending second airbag longitudinal chamber between the lower / inner fabric layer 11 and the upper / outer fabric layer 13. The region forming the second airbag chamber 24 with the second airbag longitudinal chamber forms in this case the outer overlap section ÜA außenwhile the radially further inward section of the area LKB forming the first airbag chamber 14, 16 forms the inner overlap section ÜA innen forms, as in Fig. 3a is indicated.

[0094] As continued in Fig. 3a), a start and end of the outer overlap section ÜA can optionally be außen with a beginning and end of the inner overlap section ÜA innen connected, for example, via a fixing seam FN, which is only indicated schematically. This serves, among other things, to ensure the stability of the airbag 10 when both the first airbag chamber 14, 16 and the second airbag chamber 24 are inflated.

[0095] As continued in Fig. 3b, the airbag 10 has a first partial region ETB and a second partial region ZTB as well as a region LKB forming the first airbag chamber 14, wherein the first partial region ETB is arranged between the region LKB forming the first airbag chamber 14 and the second partial region ZTB.

[0096] The warp threads and weft threads in the second partial region ZTB are woven together in such a way that the second partial region ZTB forms the generator mouth 18 for receiving a gas generator for filling the airbag and is designed in two layers, wherein the warp threads and weft threads in the region LKB forming the first airbag chamber 14, 16 are woven together in such a way that this region has the first airbag chamber 14, 16 and is designed in three layers. The warp threads and weft threads of the second fabric layer 12 emerge from the second fabric layer 12 in the first partial region ETB and float completely between the first fabric layer 11 and the third fabric layer 13 and are integrated into the first fabric layer 11 or the third fabric layer 13 in the second partial region ZTB.

[0097] Fig. 4a) shows a schematic representation of an airbag 10 according to the invention according to a third embodiment in a cross-sectional view in a state in which the first airbag chamber 14, 16 is inflated and the second airbag chamber 24 with two second airbag longitudinal chambers 24 1 and 24 2 is inflated. Fig. 4b) shows a schematic representation of the airbag 10 according to the invention of Fig. 4a) in the laid out or spread-out state in a top view. To avoid repetition, the description of this third embodiment will only focus on the differences from the second embodiment explained above, with identical or similar components being designated by the same reference numerals.

[0098] In this embodiment, the area forming the second airbag chamber 24 is formed in two layers, wherein - as in Fig. 4a - the fabric layers 11 and 13 are woven together in such a way that in the second area two second airbag longitudinal chambers 24 arranged next to each other in the circumferential direction 1 and 24 2 which are formed by a woven seam 24 WN are spaced apart from each other.

[0099] Fig. 5a) shows a schematic representation of an airbag 10 according to the invention according to a fourth embodiment in a cross-sectional view in a state in which the first airbag chamber 14, 16 is inflated and the second airbag chamber 24 with a plurality of airbag longitudinal chambers is inflated. Fig. 5b) shows a schematic representation of the airbag 10 according to the invention of Fig. 5a) in the laid out or spread-out state in a top view. To avoid repetition, the description of this fourth embodiment will only focus on the differences from the second embodiment explained above, with identical or similar components being designated by the same reference numerals.

[0100] In this embodiment, the area forming the second airbag chamber 24 is designed in three layers, wherein - as in Fig. 5a is particularly evident - the fabric layers 11, 12 and 13 are woven together in such a way that in the second area four second upper woven seams 24 arranged next to one another in the circumferential direction OWN spaced airbag longitudinal chambers 24 10 , 24 20 , 24 30 and 24 40 are formed and on the other side, in relation to the middle fabric layer, two second lower airbag longitudinal chambers 24 arranged next to each other 12u and 2434u which are formed by a woven seam 24 WN are spaced apart from each other and two of the second upper airbag longitudinal chambers 24 10 , 24 20 , 24 30 and 24 40 overlap in the radial direction.

[0101] The features of the invention disclosed in the above description, in the drawings and in the claims may be essential for the realization of the invention both individually and in any combination. Reference symbol 10 airbag 11 first / lower / outer fabric layer 12 second / middle fabric layer 13 third / upper / inner fabric layer 14 first (outer) airbag chamber 14 1 first (outer) airbag longitudinal chamber 14 2 first (outer) airbag longitudinal chamber 14 3 first (outer) airbag longitudinal chamber 14 BKfirst (outer) airbag longitudinal chamber (bridge longitudinal chamber) 16 1 first (inner) airbag longitudinal chambers 16 2 first (inner) airbag longitudinal chambers 16 3 first (inner) airbag longitudinal chambers 16 4 first (inner) airbag longitudinal chambers 16 5 first (inner) airbag longitudinal chambers 16 6 first (inner) airbag longitudinal chambers 16 7 first (inner) airbag longitudinal chambers 16 8 first (inner) airbag longitudinal chambers 18 first generator mouth 20 second generator mouth 22 Edge or peripheral woven seam 24 second airbag chamber 24 1 second airbag longitudinal chambers 24 2 second airbag longitudinal chambers 24 3 second airbag longitudinal chambers 24 4 second airbag longitudinal chambers 24 WNWoven seam between second airbag longitudinal chambers 24 OWN Woven seam between upper second airbag longitudinal chambers 24 1o second upper airbag longitudinal chambers 24 2o second upper airbag longitudinal chambers 24 3o second upper airbag longitudinal chambers 24 4o second upper airbag longitudinal chambers 24 12u second lower airbag longitudinal chambers 24 34u second lower airbag longitudinal chambers ÜB transition area S firing direction K Warp direction WN woven seam FN fixation suture ÜA außen outer overlap section ÜA innen inner overlap section

Claims

[1] Airbag (10), preferably a woven OPW airbag, which is designed to be changed from an uninflated state to an inflated state by an inflation process for the protection of an occupant of a vehicle, wherein the airbag (10) has at least two fabric layers (11, 12, 13), preferably in some areas two fabric layers (11, 12, 13) and / or in some areas three fabric layers, which are connected to one another in such a way that at least one first airbag chamber (14) and one second airbag chamber (24) separate from the first airbag chamber (14) are formed, wherein the fabric layers (11, 12, 13) are further connected to one another in such a way that - the first, preferably three-layered, airbag chamber (14) and the second, preferably two-layered or three-layered, airbag chamber (24) can be moved independently of one another from their respective uninflated state to their respective inflated state, and - the first airbag chamber (14), starting from its non-inflated state, curves outwards during a first inflation process of the first airbag chamber (14) and / or in the inflated state of the first airbag chamber (14) forms at least in sections a tubular shape with an oval or circular cross-section and in the process an overlapping section (ÜA außen ), preferably an outer overlapping section, of the second airbag chamber (24) in its non-inflated state or in its inflated state with an overlapping section (ÜA innen), preferably an inner overlapping section, which overlaps the first airbag chamber (14), preferably radially. [2] Airbag (10) according to claim 1, wherein the fabric layers (11, 12, 13) are connected to one another in such a way that the outer overlapping section (ÜA außen ) of the second airbag chamber (24) in the non-inflated state with the inner overlapping section (ÜA innen ) of the first airbag chamber (14) in the inflated state and / or curves outwards during a second inflation process of the second airbag chamber (24) or along the inner overlapping section (ÜA innen ) of the first airbag chamber (14) in the inflated state and thereby engages with the inner overlapping section (ÜA innen) of the first airbag chamber (14) in the inflated state and / or a radially outer tube wall section or hollow cylinder wall section with respect to the radially inner overlap section (ÜA innen ) of the first airbag chamber (14) in the inflated state. [3] Airbag (10) according to claim 1 or 2, wherein the first airbag chamber (14) comprises a plurality of interconnected first airbag longitudinal chambers (14 1 , 14 2 , 14 3 ) with respective first airbag chamber volumes which, in the inflated state, are arranged next to one another in the circumferential direction and / or extend axially, transversely, obliquely or helically, and / or the second airbag chamber (24) comprises a single airbag longitudinal chamber or a plurality of interconnected second airbag longitudinal chambers (24 1 , 24 2 , 24 3 , 24 4) with respective second airbag chamber volumes which, in the inflated state, are arranged next to one another in the circumferential direction and / or extend axially, transversely, obliquely or helically and / or the plurality of first airbag longitudinal chambers (14 1 , 14 2 , 14 3 ) in the circumferential direction next to the single airbag longitudinal chamber or the plurality of second airbag longitudinal chambers (24 1 , 24 2 , 24 3 , 24 4 ) is arranged. [4] Airbag (10) according to claim 3, wherein the first airbag chamber volumes of the first airbag longitudinal chambers (14 1 , 14 2 , 14 3 ) smaller, equal to or larger than the second airbag chamber volumes of the second airbag longitudinal chambers (24 1 , 24 2 , 24 3 , 24 4 ) are trained. [5] Airbag (10) according to claim 3 or 4, wherein the first airbag longitudinal chambers (14 1 , 14 2 , 14 3) and / or the second airbag longitudinal chambers (24 1 , 24 2 , 24 3 , 24 4 ) are tubular or at least partially hollow cylindrical or in the form of an elliptical hollow cylinder. [6] Airbag (10) according to one of the preceding claims 3 to 5, wherein the airbag (10) has at least in sections three fabric layers (11, 12, 13), namely a first fabric layer (11), a third fabric layer (13) and a second fabric layer (12) arranged therebetween, wherein the three fabric layers (11, 12, 13) are woven together in such a way that in a region (LKB) forming the first airbag chamber (14) there are first airbag longitudinal chambers (14 1 , 14 2 , 14 3) are formed between the first fabric layer (11) and the second fabric layer (12) and the third fabric layer (13) and the second fabric layer (12) and / or in a region forming the second airbag chamber (24) second airbag longitudinal chambers (24 1 , 24 2 , 24 3 , 24 4 ) are formed between the first fabric layer (11) and the second fabric layer (12) and the third fabric layer (13) and the second fabric layer (12), which cause an at least partial outward curvature during their respective inflation processes. [7] Airbag (10) according to one of the preceding claims 3 to 5, wherein the airbag (10) has at least in sections three fabric layers (11, 12, 13), namely a first fabric layer (11), a third fabric layer (13) and a second fabric layer (12) arranged therebetween, wherein the three fabric layers (11, 12, 13) are woven together in such a way that in a region (LKB) forming the first airbag chamber (14) there are first airbag longitudinal chambers (14 1 , 14 2 , 14 3 ) between the first fabric layer (11) and the second fabric layer (12) and the third fabric layer (13) and the second fabric layer (12), while only two fabric layers (11, 13) in a region forming the second airbag chamber (24) form one or more axially extending second airbag longitudinal chambers (24 1 , 24 2 , 24 3 , 24 4) between the first fabric layer (11) and the third fabric layer (13). [8] Airbag (10) according to one of the preceding claims, wherein the first airbag chamber (14) is connected to a region which forms a first generator mouth (18) for receiving a first gas generator or a first connection region for connecting a first gas generator, and the second airbag chamber (24) is connected to a region which forms a second generator mouth (20) separate from the first generator mouth (18) for receiving a second gas generator or a second connection region for connecting a second gas generator, so that the first airbag chamber (14) and the second airbag chamber (24) can be inflated independently of one another via their respective first or second gas generator. [9] Airbag (10) according to one of the preceding claims, wherein the airbag (10) is designed as an OPW airbag with warp threads and weft threads woven into the woven fabric layers (11, 12, 13), wherein the warp threads and weft threads are woven together in such a way that the airbag (10) has a first partial region (ETB) and a second partial region (ZTB) as well as a region (LKB) forming the first airbag chamber (14), wherein the first partial region (ETB) is arranged between the region (LKB) forming the first airbag chamber (14) and the second partial region (ZTB), wherein the warp threads and weft threads in the second partial region (ZTB) are woven together in such a way that the second partial region (ZTB) has at least one generator mouth (18) for receiving a gas generator for filling the airbag or a connection for connecting a generator and is designed in two layers, wherein the warp threads and weft threads in the region (LKB) forming the first airbag chamber (14) are woven together in such a way that the region (LKB) forming the first airbag chamber (14) has the plurality of first airbag longitudinal chambers and is formed in three layers, and wherein the warp threads and weft threads of the second fabric layer (12) emerge from the second fabric layer (12) in the first partial area (ETB) and float completely between the first fabric layer (11) and the third fabric layer (13) and are integrated into the first fabric layer (11) and / or the third fabric layer (13) in the second partial area (ZTB). [10] Airbag arrangement with an airbag (10) according to one of the preceding claims, and at least two independently activatable gas generators, wherein a first generator of the two gas generators is accommodated or connected in the first generator mouth (18) or the first connection area of ​​the first airbag chamber (14) and a second generator of the two gas generators is accommodated or connected in the second generator mouth (20) or the second connection area of ​​the second airbag chamber (24). [11] Airbag triggering device for triggering an airbag (10) with a control device and an airbag arrangement according to claim 10, wherein the control device is configured to activate the first generator to fill the first air chamber and is further configured to activate the second generator to fill the second air chamber when the first generator has already been activated and a predetermined condition is met, preferably a predetermined time has elapsed. [12] A method for deploying an airbag assembly according to claim 10, comprising the following steps: Activating the first generator to fill the first air chamber of the airbag (10), and Activating the second generator to fill the second air chamber of the airbag (10), simultaneously or after the first generator has already been activated.

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