Patent Abstract:
An airbag module with a gas generator, a gas bag, a housing containing an exit opening for the deploying gas bag, and a holder. The gas generator and holder are located inside the gas bag, and the gas generator is fixed to the housing. The holder ( 19 ) has a support area ( 20 ) and at least one deflector segment ( 21, 22 ) directed toward the exit opening ( 13 ). The holder is placed between the gas generator ( 14 ) and the housing ( 10 ). The deflector segment at least partially surrounds the gas generator ( 14 ) and directs the gas generated by the gas generator ( 14 ) into at least one of a plurality of fold packets ( 16, 17, 18 ) of the gas bag ( 15 ) placed on both sides of the deflector segment ( 21, 22 ).

Full Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The invention concerns an airbag module with a gas generator, a gas bag, a housing with an exit opening for the deploying gas bag, as well as a holder. The gas generator and the holder are located inside the gas bag and the gas generator is fixed radially and axially to the housing. 
     2. Description of Related Art 
     A related airbag module is described in DE 298 06 402 U1. In this regard, a holder, placed inside the gas bag and which fastens the gas bag to the housing using separate bolts passing through the fabric of the gas bag, is connected to the housing. The application piece is U-shaped which corresponds in its shape to the housing, which is also U-shaped. The housing has an exit opening, between its U-legs. The gas bag is folded up in the housing, and exit opening is closed with a cover. The U-shaped holder is coordinated in its dimensions to the housing in such a manner that a narrow region exists between the housing walls and the holder to house the gas bag. The gas bag itself is folded into the U-shaped housing between the exit opening and the holder. 
     Generally, in airbag modules, the requirement also exists to direct the gases released by the gas generator when it fires into predetermined areas of the folded gas bag by placing deflectors as gas directing surfaces, in this manner assuring a controlled or even sequential deployment of the gas bag. For example, DE 197 36 243 A1 discloses an air bag device in which the interior of a module housing is subdivided into differing areas or internal spaces for the placement of the gas generator, on the one hand, and of at least one or more fold packets of the folded gas bag, on the other hand. The intermediate walls cause a pre-determined introduction of the gas stream into a pre-determined folding area of the gas bag, which then, as it unfolds, extracts further folding regions of the gas bag from the housing and releases them for the introduction of gas. 
     The problem to be solved by the invention, therefore, is to provide an airbag module with the general characteristics of simple attachment for the folded gas bag and simple construction of the gas direction system. 
     The solution to this problem is shown in the content of the patent claims that follow this description, including advantageous embodiments and further developments of the invention. 
     SUMMARY OF THE INVENTION 
     In its basic form, the invention provides a holder placed between the gas generator and the housing with an attachment area. The holder has a deflector segment directed toward the exit opening and surrounding the gas generator externally. The deflector segment has a deflector surface to direct the gas generated by the gas generator into at least one of the fold packets of the gas bag placed on both sides of the deflector segment. 
     The invention also provides an advantage that the holder provided for attaching the gas bag may also be made in the shape of a deflector. The deflector, due to its shape, divides the interior of the housing into various partial spaces or into various inside rooms, in which at least two fold packets are placed and through which, as a result of the gas conducted by the holder itself, receive gas differently. As a result of the double function so arranged for the holder to fasten the gas bag, on the one hand, and to direct the gas, on the other hand, a decrease in the size and weight of the air bag module as well as simplification of its structure is provided. This results in saving manufacturing time and manufacturing costs. 
     According to a first embodiment of the invention, the gas generator may be placed in a corner area of the housing. The holder has a section which, on one side, encloses the gas generator, where a fold packet is placed between the gas generator and the exit opening, and a further fold packet in the interior space formed by the outside wall of the housing facing away from the gas generator. In this connection, the U-shaped holder may be provided with an additional segment running along the facing outside wall of the housing. 
     In an alternative embodiment, the gas generator may be placed in a central area of the housing. The holder is designed to be U-shaped with two deflector segments enclosing the gas generator between them. In this connection, the gas bag may be provided with two fold packets, each of which is placed in the interior space that exists between the deflector segment of the holder and the facing outside housing wall. A gas bag location connecting the two fold packets bridges the space located between the deflector segments and the gas generator placed therein. For the purpose of good deployment of the fold packets, the individual folds of the fold packets of the gas bag may be placed transversely to the direction of ejection of the gas bag from the housing. 
     In another alternative embodiment of the invention, three fold packets of the gas bag are provided, of which two fold packets are placed, each in the interior space between the deflector segments and the outer housing wall, and an intermediate fold packet between the gas generator and the exit opening. The individual folds of the outer packets may run transversely to the ejection direction of the gas bag and the individual folds of the central fold packet run in the ejection direction. 
     In order to obtain a greater variety in inflating the fold packets of the gas bag folded in the housing, according to one sample embodiment of the invention, at least one deflector segment passage opening is placed in the interior space defined by the deflector segment for the passage of gas from the gas generator. 
     In alternative embodiments of the invention, then, each deflector segment serving as a deflector surface may extend along a portion of the extension of the gas generator in the direction of the exit opening or corresponding to the extension of the gas generator in this direction or also extend beyond the gas generator in the direction of the exit opening. 
     The end of each deflector segment may be directed toward the exit opening from the housing is bent inward or outward with respect to the gas generator. 
     In an alternative embodiment of the invention, the gas generator may be placed centrally in the housing. The holder includes a gas generator with a deflector segment placed on one side, where three fold packets of the gas bag are provided, of which one fold packet is placed between the deflector segment and the outside housing wall. The other two fold packets are placed in the interior space of the housing divided off by the deflector segment in which the gas generator is placed. In this case, the deflector segment is placed on one side, and an extension that extends parallel to the exit opening from the housing surround the gas generator. One of the three fold packets is placed in the space between the extension of the deflector segment running parallel to the exit opening and the exit opening itself. According to one embodiment of the invention, the holder is connected to the housing. 
     In an especially suitable embodiment of the invention, the holder is placed without fastening between the gas generator and the housing. In this regard, the holder, in particular, is held fast by the gas generator without being firmly fixed to the gas bag or the gas generator or the housing on the side of the gas generator opposite the exit opening between the housing wall of the module housing and the gas generator. The holder absorbs the forces that arise during deployment of the gas bag and transmits them to the gas generator and its fastening to the module housing. Thus, the fastening of the gas bag in this sample embodiment is done in a kind of floating fastening because the gas bag fabric is guided without separate fixation or attachment around the holder. The holder is placed inside the gas bag, where the holder braces against the gas generator fastened inside the module housing, in the case of stressing due to the tensile forces applied to the gas bag as it deploys, and thereby transmits the forces. This has the advantage that the gas bag fabric is braced against the surface of the holder for the transmission of forces, and there is no point stress. As a result, no reinforcement will be applied in the manufacture of the gas bag. Also, the manufacture and installation of the airbag module are simplified, because no special measures are required on the gas bag fabric for the fastening of the holder. 
     Finally, according to one sample embodiment of the invention, the holder has a dimension coinciding with the parallel length of the gas generator in its support area oriented parallel to the housing floor; in this manner, an especially small design is assured for the airbag module, because only the necessary area of extension of the holder is used for the fastening of the gas bag fabric. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       In order that the manner in which the above-recited and other features and advantages of the invention are obtained will be readily understood, a more particular description of the invention briefly described above will be rendered by reference to specific embodiments thereof which are illustrated in the appended drawings. Understanding that these drawings depict only typical embodiments of the invention and are not therefore to be considered to be limiting of its scope, the invention will be described and explained with additional specificity and detail through the use of the accompanying drawings in which: 
         FIGS. 1   a – 1   c  show an airbag module with a gas generator placed in a corner area and a holder with a one-legged deflector segment in its original condition and in different stages of deployment of the gas bag. 
         FIGS. 2   a – 2   c  show another sample embodiment of the airbag module in the representation in accordance with  FIGS. 1   a – 1   c , with additional gas passage openings in the deflector segment of the holder. 
         FIGS. 3   a – 3   c  show an air bag module with a centrally placed gas generator and a U-shaped holder placed on both sides of the gas generation, with deflector segments in a representation corresponding to  FIGS. 1   a – 1   c.    
         FIGS. 4   a – 4   c  show the subject of  FIGS. 3   a – 3   c  with the addition of gas passage openings. 
         FIGS. 5   a – 5   c  show a further sample embodiment of the airbag module in a representation according to  FIGS. 1   a – 1   c , with a centrally placed gas generator and a one-legged holder. 
         FIGS. 6   a – 6   c  show the subject of  FIGS. 5   a – 5   c  with an extension added to the deflector segment of the holder extending parallel to the passage opening of the housing. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     The presently preferred embodiments of the present invention will be best understood by reference to the drawings, wherein like parts are designated by like numerals throughout. It will be readily understood that the components of the present invention, as generally described and illustrated in the figures herein, could be arranged and designed in a wide variety of different configurations. Thus, the following more detailed description of the embodiments of the apparatus, system, and method of the present invention, as represented in  FIGS. 1   a  through  6   c , is not intended to limit the scope of the invention, as claimed, but is merely representative of presently preferred embodiments of the invention. 
     The housing  10  represented in  FIGS. 1   a  through  1   c  of an airbag module consists of a floor area  12  and outside walls  11  extending upward therefrom, which, between themselves, define an exit opening  13  for the gas bag  15  folded in the interior of the housing  10 . In the housing  10 , generally a gas generator  14  is placed and fixed to the housing  10 . The gas generator  14  may be fixed radially, axially, or radially and axially to the housing. 
     In the sample embodiment represented in  FIGS. 1   a  through  1   c , the gas generator  14  is placed in a corner area of the housing  10  near the floor area  12 , where the gas generator  14  is inside the folded gas bag  15  and placed in the interior of a U-shaped holder  19 . The holder  19  has a leg  22  extending parallel to the outside wall  11  of the housing  10 , which, in the sample embodiment represented, works not as a deflector, but only encloses a gas bag position for the folded gas bag  15  between it and the outside wall  11 . The same applies for the support area  20  of the holder  19 . The deflector segment  21 , which extends in the direction of the exit opening  13  on the inside of the attachment area of the holder  19 , serves at the same time as a limitation for two partial spaces in which two fold packets  16  and  18  of the gas bag  15  are placed. A fold packet  18  is placed between the gas generator  14  and the exit opening  13  of the housing  10 , while a second fold packet  16  is accommodated in the space lying between the deflector segment  21  and the opposite outside wall  11  of the housing. Both folding bags  16 ,  18  have individual folds  30  running parallel to the exit opening  13  or transverse to the expulsion direction of the gas bag. In the embodiment represented in  FIGS. 1   a – 1   c , the end  24  of the deflector segment  21  is bent outward, that is, away from the gas generator  14 . 
     In all sample embodiments represented and to be described below, the holder, with deflector segment or deflector segments, is laid, without being firmly fixed to the gas bag  15  or the gas generator  14  or the housing  10 , into the interior of the gas bag  15 , so that, upon deployment of the gas bag, as shown in  FIGS. 1   b  and  1   c , the holder is pulled with its support area  20  from the gas bag position between the support area  20  and the floor area  12  of the housing, against the gas generator  14  and thereby transfers the corresponding forces to the gas generator and its fastening to the housing  10 . The support area  20  may be oriented parallel to the housing floor  12 , and it has a dimension that substantially coincides with the dimension of the gas generator, along a plane parallel to the support area. 
     In  FIGS. 1   b  and  1   c , the incipient deployment of the gas bag  15  due to the arrangement described of the fold packets in the housing can be recognized; it can be seen in which sequence the fold packets  18  followed by  16  are thrown out. 
     The sample embodiment represented in  FIGS. 2   a  through  2   c  differs from the sample embodiment described in  FIGS. 1   a  through  1   c  only through the placement of at least one additional gas passage opening  26  in the deflector segment  21 , so that substantially parallel to the gas flow in the direction of the fold packet  18 , simultaneously gas also flows through the gas passage opening  26  into the fold packet  16  beside the gas generator  14 , and provides for its early deployment. 
     The sample embodiment represented in  FIGS. 3   a  through  3   c  has a gas generator  14  placed centrally in the housing  10 . In this orientation, leg  22  functions as a deflector segment, so that the U-shaped holder  19  has two deflector segments  21  and  22  with the gas generator  14  disposed between the deflector segments  21  and  22 . Correspondingly, in this sample embodiment, three fold packets are provided, of which the outside two fold packets  16  and  17  are each placed in the intermediate space existing between the outer wall  11  and the neighboring deflector segment  21  or  22 . In addition, there is placed a third fold packet  18  in the central area between the gas generator  14  and the exit opening  13 . While the individual folds of the two outside fold packets run parallel to the exit opening  13 , the individual folds  30  of the central fold packet  18  run in the expulsion direction of the gas bag  15  from the housing  10 .  FIGS. 3   b  and  3   c  show, in detail, the effect of the gas flow from the gas generator  14  on the deployment of the fold packets  18  as well as  16  and  17 . 
     The embodiment represented in  FIGS. 4   a  through  4   c  shows, as a supplement to the embodiment described in  FIGS. 3   a  through  3   c , supplementary deflector segments  21  and  22  of the holder  19 , through which a more rapid deployment of the outside fold packets  16  and  17  is initiated. The ends  23  of the deflector segments  21  and  22  facing the exit opening  13  are bent inward to the gas generator. In addition, openings  26  allow gas from the gas generator  24  to enter fold packets  16  and  17  beside the gas generator  14  and provide for early deployment of the gas bag  15 . 
     The sample embodiment shown in  FIGS. 5   a  through  5   c  shows a centrally placed gas generator  14  and a holder  19  with one deflector segment  21 , where the placement of the fold packets  16 ,  17 ,  18  corresponds in principle to that of the sample embodiments described in  FIGS. 3   a – 3   c  and  4   a – 4   c . The removal of a deflector segment and the asymmetrical shape of the holder with respect to the deflector segments results in the deployment process represented in  FIGS. 5   b  and  5   c.    
     In the sample embodiment shown in  FIGS. 6   a  through  6   c , with a centrally located gas generator  14  and a holder  19 , with only one leg and therefore only one deflector segment  21 , the free end of the deflector segment  21 , unlike the sample embodiment according to  FIGS. 5   a – 5   c , transitions into an extension  25  which extends parallel to the exit opening  13 , where the center fold packet  18  is located in the area between the extension  25  and the exit opening  13 . As a result, the beginning of the deployment sequence is transferred to the fold packet  17  facing the open side of the holder  19 , which provides for the pulling out of the further fold packet  18  and then  16 . 
     The characteristics of the subject of these documents revealed in this description, in the patent claims, in the summary and the drawings, can be utilized individually or in any combination for the creation of the invention in its various embodiments. The present invention may be embodied in other specific forms without departing from its structures, methods, or other characteristics as described herein and claimed hereinafter. The described embodiments are to be considered only as illustrative, and not restrictive.

Technology Classification (CPC): 1