Patent Publication Number: US-2021170978-A1

Title: Side airbag and vehicle-occupant restraint system having a side airbag

Description:
RELATED APPLICATIONS 
     This application corresponds to PCT/EP2018/083732, filed Dec. 6, 2018, which claims the benefit of German Applications Nos. 10 2017 129 286.1, filed Dec. 8, 2017; 10 2018 107 885.4, filed Apr. 4, 2018; and 10 2018 120 880.4, filed Aug. 27, 2018. 
    
    
     BACKGROUND OF THE INVENTION 
     The invention relates to a side airbag of a vehicle occupant restraint system that is provided to be mounted on a vehicle seat and to a vehicle occupant restraint system comprising such side airbag. 
     For better protecting the torso and especially the head of a vehicle occupant by an airbag, said body parts are intended to be restrained as early as possible by an airbag. 
     It is also known from prior art to dispose an airbag between two vehicle seats so as to prevent the vehicle occupants from colliding in the event of a lateral collision. Such airbag is also referred to as center airbag. The airbag protects the vehicle occupant assigned thereto even from over-oscillating beyond his/her seat so that the vehicle occupant will not impact on hard structures of the vehicle interior of the adjacent side. 
     Known center airbags, but also other side airbags, are kept in position via tethers and/or outwardly mounted positioning means to prevent the vehicle occupant e.g. form over-oscillating. Tethers and positioning means further serve for defining the inflation behavior of the airbag. The use of tethers and/or positioning means is complicated, however, and increases the space required as well as the manufacturing costs. 
     SUMMARY OF THE INVENTION 
     It is the object of the invention to provide a side airbag for vehicle occupants which requires only little space and by which quick and safe positioning in the final inflated shape thereof can be attained. 
     This object is achieved by a side airbag comprising the features of claim  1 . The side airbag of a vehicle occupant restraint system is provided for being mounted especially on a vehicle seat, such as e.g. a driver seat of a vehicle, and includes an inflatable head gas cushion and an inflatable torso gas cushion connected to the head gas cushion, both of them forming separate inflatable compartments of the side airbag. The head gas cushion and the torso gas cushion are formed by separate inflatable cushions which are fastened to each other in a connecting section. 
     Said design allows to realize even complex three-dimensional shapes in the inflated condition with little effort, as the head gas cushion and the torso gas cushion are manufactured independently of each other as separate cushions. The fastening of the two cushions to each other in the connecting section allows to easily adapt the shape of the entire side airbag to the respective application. 
     Preferably, the head gas cushion is fastened to an upper end of the torso gas cushion. This helps form a side airbag in which the head gas cushion is connected to the torso gas cushion, when viewed in the vehicle vertical direction. The position of the inflated head gas cushion in space can be adapted, with this design, to the respective requirements without difficulties by attaching the head gas cushion to the torso gas cushion in the appropriate orientation. 
     Alternatively, the head gas cushion may be fastened in an upper end section on a side of the torso gas cushion close to the vehicle occupant. This helps form a side airbag in which, in the vehicle vertical direction and when viewed from the front, the head gas cushion is connected to the torso gas cushion as an element extending the torso gas cushion upwards and toward the vehicle occupant. The upper end section of the side of the torso gas cushion close to the vehicle occupant preferably describes the upper 40%, especially the upper 20% to 35%, of the longitudinal extension of the torso gas cushion in the vehicle vertical direction. 
     Above all, a curved shape of the inflated side airbag can thus be easily achieved, although both the head gas cushion and the torso gas cushion may have a simple cushion shape comprising e.g. merely two connected cut parts. 
     The side airbag includes especially a constriction between the head gas cushion and the torso gas cushion that is formed by the connecting section. 
     Both the head gas cushion and the torso gas cushion may be elongate flat cushions the inflated thickness of which is e.g. significantly smaller than their length from their lower end to their upper end in the mounted and inflated condition of the side airbag. 
     The outer wall of the respective gas cushion in this case has an outer wall portion close to the vehicle occupant in the inflated condition of the side airbag and an outer wall portion far from the vehicle occupant, the distance of said outer wall portions defining the thickness of the inflated side airbag. 
     As a result, an elongate, optionally curved, but in total flat side airbag is formed, when both cushions are interconnected in the edge sections of the outer wall portions. It would also be imaginable, however, to dispose the head gas cushion quasi transversely and to connect it on a surface of the outer wall portion close to the vehicle occupant to the upper end of the torso gas cushion so as to impart a complex three-dimensional configuration to the side airbag. It is further imaginable to dispose the head gas cushion in an upper end section of the torso gas cushion. In such embodiment, preferably the outer wall portion far from the vehicle occupant of the head gas cushion, especially an edge section of the outer wall portion far from the vehicle occupant of the head gas cushion, is connected to the outer wall portion close to the vehicle occupant of the torso gas cushion. 
     Preferably, the head gas cushion is connected to the torso gas cushion so that, in the inflated condition of the side airbag, the head gas cushion is bent vis-à-vis the torso gas cushion. This shape can be obtained by basically obliquely attaching and connecting two separate cushions to each other. Advantageously, the angle is selected so that the head gas cushion in the inflated condition is inclined toward the assigned vehicle seat so that the head of the vehicle occupant in the vehicle seat can be absorbed early and gently. 
     In general, this allows to achieve that an occupant side of the side airbag formed by the outer wall portions close to the vehicle occupant of the head gas cushion and of the torso gas cushion extends in a concavely curved manner. 
     This shape of the side airbag causes the head gas cushion to be positioned toward the vehicle occupant during inflation already so that early and gently contact can be established with the occupant. 
     A head gas cushion whose outer wall portion far from the vehicle occupant is connected to the outer wall portion close to the vehicle occupant of the torso gas cushion further results in the advantage that the head gas cushion in the deployed and filled condition can bear against the upper end section of the torso gas cushion which is located above the connecting section in the vehicle vertical direction. 
     The outer wall of the head gas cushion may include two outer wall portions interconnected along a peripheral line. Said peripheral line defines a head gas cushion parting plane. Correspondingly, the outer wall of the torso gas cushion may include two outer wall portions interconnected along a peripheral line, the peripheral line defining a torso gas cushion parting plane. The head gas cushion parting plane is preferably inclined at an angle of about 20° to 90° vis-à-vis the torso gas cushion parting plane. 
     The peripheral line is formed by the connection of the outer wall portions into a cushion shape. In the simplest case, two separate outer wall portions are provided which are interconnected along their edges in the peripheral line so as to form a cushion. One variant provides only one single cut part for each gas cushion that is folded once back onto itself so that two superimposed outer wall portions are formed which are interconnected at the free edges, thus forming the cushion. The connection of the edges may be made in any proper way, especially by stitching, gluing or welding. It is also possible, of course, to produce the two outer wall portions in a joint weaving operation in which the entire cushion is woven in one piece and warp and weft threads of the outer wall portions merge into a joint peripheral line at the edges of the outer wall portions. 
     For bending the head gas cushion relative to the torso gas cushion, the connecting section between the head gas cushion and the torso gas cushion is advantageously located on the side close to the vehicle occupant of the parting planes of the two gas cushions. This results in curvature of the inflated side airbag toward the vehicle occupant, when viewed along the vehicle vertical direction. 
     As an alternative, the head gas cushion can be bent relative to the torso gas cushion by the connecting section between the head gas cushion and the torso gas cushion being located at the torso gas cushion in an upper end section on the side close to the vehicle occupant of the parting plane of the torso gas cushion, whereas at the head gas cushion the connecting section is located on the side far from the vehicle occupant of the parting plane of the head gas cushion. Thus, during inflation of the side airbag, the head gas cushion is pressed toward the vehicle occupant (when viewed along the vehicle vertical direction), which equally results in a curvature of the inflated side airbag toward the vehicle occupant. In the vehicle vertical direction, the connecting section is preferably located in the upper 40% of the torso gas cushion. In preferred embodiments, the connecting section is especially located in the upper third and/or in the area of the upper 25% to 35% of the torso gas cushion. Each of the % values relates to a length of the torso gas cushion in the vehicle vertical direction. 
     An extension of the head gas cushion and the torso gas cushion along the respective parting plane, when viewed in the vehicle longitudinal direction, is preferably larger than a thickness of the inflated head or torso gas cushion, i.e. larger than the distance of the respective outer wall portions. 
     It is possible to manufacture the side airbag so that all cut parts of the outer wall portions can be separately flatly spread. Basically, the entire side airbag could be formed of only two cut parts one of which forms the head gas cushion and the other forms the torso gas cushion. It is also possible, of course, to impart a three-dimensional shape to the outer wall portions, for example by introducing gathered seams or darts to originally flat cut parts or by weaving the two cushions three-dimensionally from the start. 
     Moreover, a three-dimensional shape can be imparted to the outer wall portions of the torso gas cushion and/or of the head gas cushion by one or more shaping tethers introduced to the respective gas cushion. 
     It is further possible that at least one outer wall portion and/or one cut part of the head gas cushion and/or of the torso gas cushion comprises a shaping portion. Such shaping portion may help adapt the thickness of the head gas cushion and/or of the torso gas cushion, for example, to increase an impact surface for the vehicle occupant or to improve vehicle occupant restraint. For example, such shaping portion may help change the shape and the thickness of the head gas cushion and/or the torso gas cushion even in portions only. 
     Moreover, the head gas cushion and/or the torso gas cushion may be provided to include, by a shaping tether and/or a shaping portion, in a section forward in the vehicle longitudinal direction a bulging deformation by which the respective gas cushion is partially thickened in the front section. 
     The shaping tether is preferably disposed, in the head gas cushion and/or the torso gas cushion, behind the section including the bulged deformation and the resulting partial thickening. By the at least one shaping tether the outer wall portions close to the vehicle occupant and far from the vehicle occupant of the head gas cushion and/or of the torso gas cushion are held together partially more closely in this section so that the bulged deformation is especially formed in the front section. 
     In the head gas cushion such bulged deformation may serve, especially in an oblique frontal collision, for establishing an early contact with the occupant and limiting a forward movement of the vehicle occupant along the side airbag. Alternatively, or additionally, also such bulged deformation of the torso gas cushion may serve, especially in oblique frontal collision, for establishing an early and gentle contact with the occupant and for limiting a forward movement of the vehicle occupant along the side airbag. Thus, especially by such side airbag the movement of the vehicle occupant both in the vehicle transverse direction and in the vehicle longitudinal direction can be limited in the situation of restraint. 
     Apart from an enlarged impact surface, such shaping may also be utilized e.g. for stabilizing the side airbag. 
     Alternatively, and/or additionally, the shaping can be brought about by the shaping portion. Such shaping portion is preferably formed integrally with the respective cut part and/or outer wall portion so that the cut part and/or the outer wall portion initially can be flatly spread. 
     Preferably, the cut part comprising the shaping portion is larger in the flatly spread state than the cut part to which it is connected along the peripheral line to form the head gas cushion or the torso gas cushion. In such embodiment, preferably a respective one of the outer wall portions is formed by one of the cut parts. For enabling the cut parts to be connected, initially outer edges of the shaping portion are interconnected in the area of connecting portions so that, in a top view, the cut part has substantially the same cut shape as the cut part without the shaping portion. Then the cut parts can be interconnected along the peripheral line. Alternatively, connecting the connecting portions of the shaping portion and connecting the cut parts along the peripheral line may be performed in one working step. 
     If the head gas cushion or the torso gas cushion is made from one single cut part, the shaping portion is arranged in an area forming one of the two outer wall portions. In order to connect the two areas of the cut part that form the outer wall portions to each other, the connecting portions of the shaping portion are interconnected such that the areas of the cut part forming the outer wall portions can be interconnected along the peripheral line. Connecting the connecting portions and the areas of the cut part forming the outer wall portions may be take place in successive separate working steps or during the same working step. 
     It is equally imaginable to provide non-inflatable sections in which for example opposite outer wall portions are interconnected while being directly superimposed in one or both of the gas cushions so as to increase the stability of the side airbag and to obtain individual forming. 
     Furthermore, an upper edge of the head gas cushion (relating to the inflated condition of the side airbag) may have a concave curvature. The concave curvature is configured especially such that the length of the trailing edge of the head gas cushion facing the vehicle occupant is shorter than the length of the leading edge of the head gas cushion facing away from the vehicle occupant. Alternatively, the length of the trailing edge of the head gas cushion facing the vehicle occupant moreover may be shorter than the length of the leading edge of the head gas cushion facing away from the vehicle occupant, the upper edge being substantially configured as a straight line without any curvature. 
     Such configuration, especially a concavely curved forming of the upper edge of the head gas cushion may help, for example during oblique frontal collision, to establish an early gentle contact with the vehicle occupant and to limit a forward movement of the vehicle occupant along the side airbag. 
     The inflatable volume of the head gas cushion may be smaller than that of the torso gas cushion. 
     Advantageously, the connecting section has at least one overflow orifice that fluidically connects the head gas cushion to the torso gas cushion so that both cushions can be filled through one single inflator. The connecting section further may include plural overflow orifices arranged especially along a substantially straight line. 
     The connecting section between the head gas cushion and the torso gas cushion may especially take an elongate shape. A longitudinal axis of the connecting section substantially corresponding to a line that connects the two points of the connecting section which are most distant from each other constitutes a pivot axis in typical embodiments of the side airbag. During deployment and filling of the side airbag, the head gas cushion swivels about the pivot axis to the position bent vis-à-vis the torso gas cushion. 
     The pivot axis formed by the connecting section between the torso gas cushion and the head gas cushion is preferably arranged at an angle from 20° to 90° with the vehicle vertical axis. Especially in one embodiment in which the head gas cushion is arranged at an upper edge section of the torso gas cushion, the pivot axis is preferably arranged at an angle from 85° to 90° with the vehicle vertical axis. Particularly in an embodiment in which the head gas cushion is arranged at an upper end section of the torso gas cushion, the pivot axis is preferably arranged at an angle from 30° to 70°, preferably from 40° to 55°, with the vehicle vertical axis. Especially by arranging the pivot axis at an angle of less than 90°, the connecting section directed obliquely forwardly downward in the inflated condition (relating to the vehicle vertical and longitudinal directions) may help establish early contact between the side airbag and the shoulder and arm area of the vehicle occupant. 
     Furthermore, the side airbag may comprise a positioning element. In a typical embodiment, the positioning element is fastened both to the torso gas cushion and to the head gas cushion of the side airbag. The positioning element may be, for example, a fabric element which is fastened, relating to the inflated condition of the side airbag, to a leading edge at the peripheral line of each of the torso gas cushion and the head gas cushion. The positioning element may be a one-part or multi-part element. For example, the positioning element may consist of two fabric elements that are interconnected by a connecting line. By arranging the connecting line of the fabric elements, the positioning of the head gas cushion relative to the torso gas cushion can additionally be influenced. 
     The positioning and/or the location of the head gas cushion relative to the torso gas cushion can be especially optimized and/or stabilized by the positioning element. For example, a positioning element can help minimize the risk of buckling of the head gas cushion. 
     The object according to the invention is also achieved by a vehicle occupant restraint system comprising the features of claim  19  in which a side airbag as afore-described is mounted as a center airbag on a driver seat of a vehicle on the side facing a passenger seat of the vehicle. Thus, the side airbag does not only offer a protective effect to the driver but also prevents any contact between the driver and the front passenger. 
     The torso gas cushion advantageously includes an injecting portion which is fixed to a backrest, especially to a side face of a seat, of a vehicle seat assigned to the vehicle occupant and via which the entire side airbag is fastened on the vehicle seat. 
     Typically, just as for known side airbags, a mounting space is provided inside the backrest of a vehicle seat. The mounting space may be located in the area of a medium height of a side face of the seat, when mounting takes place at sitting areas having separate vehicle seats. Alternatively, the mounting space may also be provided at a central armrest of a continuous bench. 
     It is possible to design the side airbag without any outer stabilizing straps or other outwardly attached positioning means and to fix the side airbag on the vehicle side especially only in the area of the injection mouth. 
     Designations such as “downward” and “upward” are always referred to a consideration along the vehicle vertical direction. 
    
    
     
       DESCRIPTION OF THE DRAWINGS 
       In the following, the invention shall be described in greater detail by way of an example embodiment and with reference to the attached drawings, wherein: 
         FIG. 1  is a schematic sectional view of a completely inflated side airbag according to the invention of a vehicle occupant restraint system according to the invention; 
         FIG. 2  is a schematic perspective representation of the vehicle occupant restraint system from  FIG. 1  in a front view; 
         FIG. 3  shows the vehicle occupant restraint system from  FIG. 2  in a lateral view; 
         FIG. 4  is a schematic front view of another embodiment of a completely inflated side airbag according to the invention of a vehicle occupant restraint system according to the invention; 
         FIG. 5  is a schematic view of an embodiment of a flatly spread non-inflated side airbag according to the invention; 
         FIG. 6  is a schematic front view of an embodiment of a completely inflated side airbag according to the invention of a vehicle occupant restraint system according to the invention in a situation of restraint; 
         FIG. 7  is a schematic top view of the side airbag of the vehicle restraint system according to  FIG. 6 ; 
         FIG. 8  is a schematic front view of another embodiment of a completely inflated side airbag according to the invention of a vehicle occupant restraint system according to the invention in a situation of restraint; 
         FIGS. 9 a   ) and  b ) show a schematic front view of another embodiment of a completely inflated side airbag according to the invention of a vehicle occupant restraint system according to the invention at different times in a situation of restraint; 
         FIG. 10  is a schematic view of another embodiment of a flatly spread non-inflated side airbag according to the invention; 
         FIG. 11  is a schematic lateral view of the flatly spread non-inflated side airbag according to  FIG. 10  in a location positioned facing a vehicle occupant; 
         FIGS. 12 a   ) and  b ) are schematic representations of an embodiment of cut parts of a head gas cushion of the side airbag according to the invention as set forth in  FIG. 4 ; 
         FIGS. 13 a   ),  b ) and  c ) are schematic representations of another embodiment of cut parts of a head gas cushion for a side airbag according to the invention of a vehicle occupant restraint system according to the invention; and 
         FIG. 14  is a schematic front view of another embodiment of a completely inflated side airbag according to the invention of a vehicle occupant restraint system according to the invention comprising a head gas cushion according to  FIG. 13 . 
     
    
    
     DESCRIPTION 
     The Figures illustrate a vehicle occupant restraint system  10  comprising a side airbag  12  that is arranged on a backrest of a vehicle seat  14 , in this case on a vehicle seat  14  (partly indicated in the Figures) on the side facing a passenger seat  16 . 
     The side airbag  12  includes an inflatable head gas cushion  18  and an inflatable torso gas cushion  20  connected downwards thereto along a vehicle vertical direction V. Each of the head gas cushion  18  and the torso gas cushion  20  forms an inflatable compartment of the side airbag  12 . The head gas cushion  18  constitutes an upper end of the side airbag  12  in the mounted and inflated condition of the side airbag  12 . 
     The head gas cushion  18  and the torso gas cushion  20  are formed by separate prefabricated inflatable cushions which are fastened to each other in a connecting section  22  so that the head gas cushion  18  is attached in the area of an upper end  24  of the torso gas cushion  20 . 
     The connecting section  22  includes at least one overflow orifice  26  fluidically connecting the head gas cushion  18  to the torso gas cushion  20  and allowing filling gas to overflow from the torso gas cushion  20  into the head gas cushion  18 . 
     In this example, the head gas cushion  18  and the torso gas cushion  20  are attached to each other by sewing in the connecting section  22 , the seamline enclosing the overflow orifice  26  and sealing it from the environment of the side airbag  12  in a gastight manner. 
     In the embodiment illustrated in the Figures, the head gas cushion  18  is obliquely attached to the torso gas cushion  20  so that, in the inflated condition of the side airbag  12 , it is bent vis-à-vis the torso gas cushion  20  toward a head of a vehicle occupant  28  seated on the vehicle seat  14 . 
     Both the head gas cushion  18  and the torso gas cushion  20  in this case are substantially flat cushions, each having an outer wall portion  30   a ,  30   b  close to the vehicle occupant and facing the vehicle occupant  28  and an outer, wall portion  32   a ,  32   b  far from the vehicle occupant and facing away from the vehicle occupant  28 . Here, the reference numerals  30   a ,  32   a  are associated with the head gas cushion  18 , while the reference numerals  30   b ,  32   b  refer to the torso gas cushion  20 . 
     Therefore, an occupant side  34  of the side airbag  12  formed of the two outer wall portions  30   a ,  30   b  close to the vehicle occupant extends to be concavely curved toward the vehicle occupant  28 . 
     A thickness dT of the torso gas cushion  20  and, resp., dK of the head gas cushion  18  that is defined as a distance between the respective outer wall portions  30   a ,  32   a  and  30   b ,  32   b  is definitely smaller in this example than a longitudinal extension of the outer wall portions  30   a ,  32   a  and, resp.,  30   b ,  32   b.    
     The outer wall portions  30   a ,  32   a  of the head gas cushion  18  are interconnected along a first peripheral line  36   a . The peripheral line  36   a  is circumferential in the case of a flat cushion in the area of the maximum periphery of the cushion. The first peripheral line  36   a  defines a head gas cushion parting plane EK. The outer wall portions  30   b ,  32   b  of the torso gas cushion  20  are correspondingly interconnected along a second peripheral line  36   b  defining a torso gas cushion parting plane ET. 
     Since the head gas cushion  18  is arranged to be inclined toward the vehicle occupant  28 , the head gas cushion parting plane EK is located at an angle α from about 20° to 90° with the torso gas cushion parting plane ET, the angle α opening toward the vehicle occupant  28 . 
     In a possible example, each of the outer wall portions  30   a ,  32   a  and the outer wall portions  30   b ,  32   b  are separate cut parts, the outer wall portions  30   a ,  32   a  being interconnected along the first peripheral line  36   a  and forming the head gas cushion  18 , while the outer wall portions  30   b ,  32   b  being interconnected along the second peripheral line  36   b  and forming the torso gas cushion  20 . 
     The torso gas cushion parting plane ET in this case is approximately in parallel to the vehicle vertical plane V as well as approximately in parallel to the vehicle longitudinal direction x (viz. directed into the image plane in  FIG. 1 , cf. also  FIGS. 2 and 3 ). 
     In the embodiment shown here, the connecting section  22  is located on the outer wall portions  30   a ,  30   b , i.e. in the area of each of the head gas cushion  18  and the torso gas cushion  20  which is located on the side of the parting planes EK, ET facing the vehicle occupant  28  and the vehicle seat  14 . 
     The connecting section  22  is provided on the surface of each of the outer wall portions  30   a,    30   b.    
     However, it would also be possible to arrange the connecting section  22  e.g. at the second peripheral line  36   b  of the torso gas cushion  20  and on the surface of the outer wall portion  30   a  of the head gas cushion  18  or at the first peripheral line  36   a  of the head gas cushion  18  and on the surface of the outer wall portion  30   b  of the torso gas cushion  20 , which would equally result in the head gas cushion  18  being bent vis-à-vis the torso gas cushion  20 . 
     For manufacturing the side airbag  12 , the head gas cushion  18  and the torso gas cushion  20  are separately prefabricated, e.g. by connecting their respective outer wall portions  30   a ,  32   a  and  30   b ,  32   b  to the respective peripheral lines  36   a ,  36   b . Subsequently, the head gas cushion  18  and the torso gas cushion  20  are fastened to each other in the desired spatial alignment of the head gas cushion  18  in the connecting section  22 , with the overflow orifice  26  being also disposed in the connecting section  22 . 
     As is evident especially from  FIGS. 2 and 3 , in this example the volume of the head gas cushion  18  is larger than that of the torso gas cushion  20 . 
     In the inflated condition of the side airbag  12 , the connecting section  22  between the torso gas cushion  20  and the head gas cushion  18  in this case is approximately level with a shoulder of the vehicle occupant  28  (relating to a 95% dummy). The head gas cushion  18  is inclined toward the head of the vehicle occupant  28  above the shoulder. 
     Both the head gas cushion  18  and the torso gas cushion  20  in this example have a stabilizing non-inflatable area  38  (see  FIG. 3 ) in which the outer wall portions  30   a ,  32   a  and, resp.,  30   b ,  32   b  are directly interconnected. 
     In this embodiment, neither inside nor outside the gas cushions  18 ,  20  are provided any tethers, stabilizers or further inflatable compartments. However, it is easily possible to provide fastening straps located outside the head gas cushion  18  and the torso gas cushion  20 , for example, which connect the torso gas cushion  20  to the vehicle seat  14  so as to increase the stability of the side airbag  12 . 
     Further, instead of the non-inflatable sections  38  in the head gas cushion and/or in the torso gas cushion, a shaping and preferably stabilizing tether may be disposed. 
     The side airbag  12  is filled, as conventionally known, via an inflator that is arranged at a mounting position approximately at half height of a backrest of the vehicle seat  14 , relating to the vehicle vertical direction V, where also a receptacle for the folded side airbag  12  is located. The side airbag  12  is housed in said receptacle prior to deployment thereof, wherein it is fixed to the vehicle seat  14  by an injection portion  40  (only indicated in  FIG. 1 ). 
     During inflation, the entire side airbag  12  is aligned with the vehicle occupant  28  due to the head gas cushion  18  obliquely attached to the torso gas cushion  20 , without any tensile force having to be exerted on the head gas cushion  18 , as this corresponds to the natural configuration of the side airbag  12  predetermined by the shape of the outer wall portions  30   a ,  30   b ,  32   a ,  32   b.    
     The filling rate of the head gas cushion  18 , for example, can be adapted via the size and the design of the at least one overflow orifice  26 . 
       FIG. 4  illustrates the vehicle occupant restraint system  10  showing a second embodiment of the side airbag  12 . The side airbag  12  of  FIG. 4  substantially corresponds to the afore-described side airbag  12 . In the following, only differences in the embodiments shall be emphasized and described in detail. 
     The side airbag  12  illustrated in  FIG. 4  includes a positioning element  42 . The positioning element  42  (shown in hatched lines) in the shown embodiment is a fabric element which is connected to the head gas cushion  18  and the torso gas cushion  20  in the area of the peripheral line  36   a  and  36   b . The positioning element  42  especially configured as fabric element is disposed and fastened at the leading edge formed by the peripheral line  36   a  and  36   b  on each of the head gas cushion  18  and the torso gas cushion  20  (relating to the vehicle longitudinal direction x according to  FIG. 3 ). 
       FIG. 5  illustrates an embodiment of a side airbag  12  according to the invention comprising a positioning element  42  in a non-inflated and flatly spread condition. The head gas cushion  18  is fastened to the upper end  24  of the torso gas cushion  20  via a seam  44 . The overflow orifices  26  are disposed in the connecting section substantially along a straight line forming a pivot axis SK. During inflation and filling of the side airbag  14 , the head gas cushion  18  swivels about the pivot axis SK into the position directed toward the vehicle occupant  28  as shown in  FIG. 4 , for example. The pivot axis SK is arranged, in the shown embodiment, at an angle α of about 90° with the vehicle vertical axis V. The positioning element  42  may help additionally optimize and/or stabilize the positioning and/or the position of the head gas cushion relative to the torso gas cushion. 
       FIG. 5  further illustrates that the upper edge  53  of the head gas cushion  18  of the side airbag  12  has a concave curvature  80 . In an inflated condition of the side airbag  12 , the upper edge  53  corresponds to the top edge of the head gas cushion  18 . In addition, the trailing edge  54  of the head gas cushion  18  has a smaller length than the leading edge  56  of the head gas cushion  18 . In  FIGS. 12 a   ) and  b ), the cut parts  50   a  and  52   a  are schematically shown with possible further contours of the upper edge  53  of the head gas cushion  18 . On the one hand, a contour of the upper edge  53  is shown without a concave curvature (continuous line) and, on the other hand, a contour of the upper edge is shown with a strong concave curvature  80  (broken line). 
     Such forming can help, for example in the event of an oblique frontal collision, establish early contact with the vehicle occupant  28  and limit forward movement of the vehicle occupant  28  along the side airbag  12 . 
       FIG. 6  illustrates the side airbag  14  comprising the positioning element  42  in a situation of restraint in the inflated and deployed condition. The arrows  62   a  and  62   b  show that in the area of the connecting section  22  the curved outer contours  64   a  of the head gas cushion  18  and  64   b  of the torso gas cushion  20  support rotation or swiveling of the head gas cushion  18  about the pivot axis SK during inflation and deployment of the side airbag  14 . 
     In  FIG. 7 , the vehicle occupant restraint system  12  from  FIG. 6  is shown in a top view. In the head gas cushion  18  a shaping tether  48  (see also  FIG. 5 ) is integrated. The shaping tether  48  helps to produce a bulged deformation  66  (shown in broken lines in  FIG. 7 ) at the head gas cushion  18  toward the leading edge. The bulged deformation  66  can help establish early contact of the vehicle occupant  28  (in the Figures partly shown as a dummy) with the head gas cushion  18  and limit a forward movement of the vehicle occupant  28  along the head gas cushion  18  in a situation of restraint caused by oblique frontal collision, for example. Upon impact of the vehicle occupant, the head gas cushion  18  can adopt the contour shown by the line  68 , for example, and, as afore-described, can limit the forward movement of the vehicle occupant  28  along the outer wall portion  30   a  close to the vehicle occupant of the head gas cushion. The limitation of the movement of the vehicle occupant  28  by the side airbag  14  is schematically shown by the arrows  70 . 
     In  FIG. 8  another embodiment of a side airbag  12  according to the invention is illustrated. The side airbag  12  differs from the afore-shown side airbags  12  by the fact that the connecting section  22  is located between the head gas cushion  18  and the torso gas cushion  20  in such embodiment at the head gas cushion  18  on the side of the parting plane EK far from the vehicle occupant on the outer wall portion  32   a  far from the vehicle occupant. In addition, the connecting section  22  is located in an upper end section  72  of the torso gas cushion  20 . The upper end section  72  of the torso gas cushion  20  preferably describes the upper 40% of the torso gas cushion  20 , especially the upper third (when viewed in the vehicle vertical direction V). 
     The arrows  62   a  and  62   b  show that even in such embodiment the curved outer contour  64   a  of the head gas cushion  18  and  64   b  of the torso gas cushion  20  supports rotation and, resp., swiveling of the head gas cushion  18  about the pivot axis SK (see  FIG. 11 ) during inflation and deployment of the side airbag  14 . The additional airbag volume of the torso gas cushion  20  disposed in the upper end section  72  above the connecting section  22  may allow an additional support element for the head gas cushion  18  to be provided in the shown situation of restraint. Especially by the upper end section  72  of the torso gas cushion  20  the positioning and/or the position of the head gas cushion  18  relative to the torso gas cushion  20  can be additionally optimized and/or stabilized. For example, in the situation of restraint, the head gas cushion  18  can thus be prevented from “buckling” to the side by the upwardly protruding end section  72  of the torso gas cushion  20 . 
     In  FIGS. 9 a   ) and  b ), another embodiment of a side airbag  12  according to the invention of a vehicle occupant restraint system  10  according to the invention is shown at different times in a situation of restraint. In  FIG. 9 a   ), the vehicle occupant restraint system  10  is shown at the beginning of the situation of restraint, immediately after the side airbag  12  has been completely deployed and inflated. In  FIG. 9 b   ), the vehicle occupant restraint system  10  is shown at a later time in the situation of restraint at which the vehicle occupant  28  is restrained by the side airbag  12 . 
     The connecting section  22  between the head gas cushion  18  and the torso gas cushion  20  in this embodiment of the side airbag  12  is equally located at the head gas cushion  18  on the side of the parting plane EK far from the vehicle occupant  28  on the outer wall portion  32   a  far from the vehicle occupant. The connecting section in this embodiment is located at the torso gas cushion  20  in the upper end section  72  on the side of the parting plane ET close to the vehicle occupant on the outer wall portion  30   b  close to the vehicle occupant. The side airbag  12  of  FIG. 9  differs from the side airbag of  FIG. 8  by a larger head gas cushion  18 . The head gas cushion  18  has a larger expansion especially in the vehicle vertical direction V, which allows to enlarge the protective area for avoiding interaction with adjacent vehicle components or with another vehicle occupant on a passenger seat  16 , for example. 
     In  FIG. 10 , an embodiment according to the invention of a side airbag  12  is illustrated in a non-inflated and flatly spread condition. In contrast to the embodiment according to  FIG. 5  in which the connecting section  22  is located at the head gas cushion  18  on the outer wall portion  30   a  close to the vehicle occupant, the connecting section  22  of the side airbag  12  according to  FIG. 10  is located at the head gas cushion  18  on the outer wall portion  32   a  far from the vehicle occupant. 
     The pivot axis SK of the side airbag  12  in the shown embodiment is disposed at an angle α of about 50° with the vehicle vertical axis V. 
     Alternatively to the head gas cushion  18  shown in  FIG. 10 , the side airbag  12  may equally have a head gas cushion  18  that has a contour according to a head gas cushion  18  formed by the cut parts  50   a  and  52   a  shown in  FIG. 12 . The overflow orifices  26  are disposed, in such embodiment, in the outer wall portion  32  far from the vehicle occupant which is formed by the cut part  52   a.    
       FIG. 11  illustrates the side airbag  12  from  FIG. 10  positioned relative to the vehicle occupant  28  (shown by a dummy) in a flatly spread non-inflated condition. The arrangement of the connecting section  22  and the pivot axis SK inclined about the angle α helps provide a contour shown by the line  77  at the side airbag  12 , which contour may limit a forward movement (shown by the arrows  74 ) of the vehicle occupant  28  by “arresting” the shoulder and arm area  78 . Due to the inclined arrangement of the lower edge of the head gas cushion  18  in the connecting section  22 , in a situation of restraint the head gas cushion exerts a force (schematically shown by the arrows  76 ) limiting the forward movement on the shoulder and arm area  78  of the vehicle occupant  28 . Thus, accelerations acting on the vehicle occupant  28 , for example, may be additionally minimized in the situation of restraint. 
       FIGS. 12 a   ) and  b ) schematically illustrate the cut parts  50   a  and  52   a  of the head gas cushion  18  of the preceding Figures. For forming the head gas cushion  18 , the cut parts  50   a  and  52   a  are interconnected, for example sewn, along the peripheral line portions  53   a  to  56   a  and  53   b  to  56   b . During connection, the peripheral line portion  53   a  is connected to the peripheral line portion  53   b , the peripheral line portion  54   a  is connected to the peripheral line portion  54   b , the peripheral line portion  55   a  is connected to the peripheral line portion  55   b  and the peripheral line portion  56   a  is connected to the peripheral line portion  56   b . The cut parts  50   a  and  52   a  constitute the outer wall portions  30   a  and  32   a  of the head gas cushion  18  in the shown embodiment. 
     In the cut part  50   a  moreover overflow orifices  26  as well as the seam line  44  which encloses the overflow orifices and at which the head gas cushion  18  is connected to the torso gas cushion  20  are shown. 
       FIGS. 13 a   ) to  c ) schematically show equally cut parts  50   a  and  52   a ′ of a head gas cushion  18 . The cut part  50   a  is identical to the cut part  50   a  shown in  FIG. 5 . The cut part  52   a ′ differs from the cut part  52   a  in that the latter comprises a shaping portion  57 . The shaping portion  57  may help adapt the volume and the shape of the head gas cushion  18  in the inflated condition. 
     For interconnecting the peripheral line portions  55   a  and  55   b ′ as well as  53   a  and  53   a ′ of the cut parts  50   a  and  52   a ′, in the shown embodiment in a first step the shaping portion  57  is folded along the folding edge  60  so that the connecting portions  58   a  and  58   b  to the connecting line  58  and the connecting portions  59   a  and  59   b  to the connecting line  59  can be interconnected. In this way, the cut part  52   a ′ shown in  FIG. 13 c   ) is formed, with the shaping portion  57  being shown in broken lines for better overview. In a second step, subsequently the peripheral line portion  53   a  is connected to the peripheral line portion  53   b ′, the peripheral line portion  54   a  is connected to the peripheral line portion  54   b ′, the peripheral line portion  55   a  is connected to the peripheral line portion  55   b ′ and the peripheral line portion  56   a  is connected to the peripheral line portion  56   b ′ of the cut parts  50   a  and  52   a′.    
     As is evident from  FIG. 14 , the head gas cushion  18 ′ being formed has a larger thickness dk′ between the outer wall portions  30   a  and  32   a ′ as compared to the head gas cushion  18  shown in  FIGS. 1 to 4 . The shaping portion helps increase and adapt the volume and the thickness dk′ of the head gas cushion and thus the lateral impact area for the head of the vehicle occupant  28 . For better overview, the broken line shows the contour of the outer wall portion  32   a  of the head gas cushion  18  without any shaping portion  57 . The side airbag  12  corresponds to the side airbag  12  of  FIG. 4  except for the head gas cushion  18 ′. 
     Such shaping portion  57  may be arranged, depending on the embodiment and the requirements, in each of the outer wall portions of a side airbag  12  according to the invention. The shaping portion and the folding edge of the shaping portion may also be freely aligned, in response to the requirements, within a cut part and/or an outer wall portion. 
     Although the invention has been described for a side airbag in the form of a center airbag, the illustrated principle can also be conferred upon other airbags at the discretion of those skilled in the art, of course.