Abstract:
A side impact protective device for vehicle occupants is arranged along a roof frame of a vehicle and includes a cladding part for covering the roof frame, a head gas bag and mounting members. The head gas bag is convertible from a folded state to an unfolded state and has, in its unfolded state, an upper part with two outer end portions. The head gas bag is arranged underneath the cladding part in the folded state extended in a longitudinal direction substantially parallel to the roof frame and only folded in a direction transversely to the longitudinal direction. The mounting members serve to attach the head gas bag at least at the outer end portions to the roof frame.

Description:
This application is a continuation-in-part of application application Ser. No. 08/800,262 filed on Feb. 13, 1997, now abandoned. 
    
    
     FIELD OF THE INVENTION 
     The present invention relates to a side impact protective device for vehicle occupants. 
     BACKGROUND OF THE INVENTION 
     A side impact protective device is disclosed in the German patent publication 3,422,263 C2. The device comprises a gas-filled supply container for the inflation of the head gas bag which is arranged in a longitudinal beam of the vehicle, i.e., in the door sill region and is connected by a duct with a head gas bag. In an accident the folded gas bag arranged underneath the cladding part on the roof frame either bursts open the cladding part or deforms it and upon inflation deploys to the side of an occupant between his head and the side window. The position of the inflated head gas bag and its direction of deployment are however not completely regular and controlled, something possibly leading to a delay in the inflation step and to safety risks, if the gas bag is not exactly arranged to the side of the head of such vehicle occupant or if during a side impact it can shift in relation to the head of the occupant. 
     The German patent publication 2,249,988 A discloses a side impact protective device comprising an inflatable head gas bag which together with a pressurized gas container is secured in a recess in a cladding part on the roof frame so that the cladding part does not surround the folded head gas bag and the bag is likely to be accidentally or otherwise damaged by same. Furthermore, the container extends along the entire length of the head gas bag and is made correspondingly large in size, which makes it more difficult to accommodate the gas bag in the vehicle. 
     SUMMARY OF THE INVENTION 
     The invention provides a side impact protective device with which the position of the head gas bag both in the deployed state and in the course of inflation itself is consistently controlled. 
     The side impact protective device according to the invention is arranged along a roof frame of a vehicle and includes a cladding part for covering the roof frame, a head gas bag and mounting means. The head gas bag is convertible from a folded state to an unfolded state and has, in its unfolded state, an upper part with two outer end portions. The head gas bag is arranged underneath the cladding part in the folded state extended in a longitudinal direction substantially parallel to the roof frame and only folded in a direction transversely to the longitudinal direction. The mounting means serve to attach the head gas bag at least at the outer end portions to the roof frame. 
     The head gas bag is accordingly arranged in a predetermined manner even in its unfolded condition for its full longitudinal extent in the vehicle, since it is not folded in the longitudinal direction. The unfolding operation must consequently take place principally only in the vertical direction and in the direction toward the head of the vehicle occupant. It is hence possible to avoid disordered unfolding. Furthermore, the position of the head gas bag is consequently defined and regular in the inflated state as well so that displacement of the head gas bag in relation to the vehicle may not occur with the side crash protective device of the invention. 
     In accordance with a preferred embodiment the head gas bag is provided on its ends attached to the roof frame with attachment eyes to facilitate fitting to the roof frame. Thus it is only necessary to provide hooks or screws on the roof frame. 
     In accordance with a further embodiment an associated elongated gas generator is arranged parallel to the folded head gas bag underneath the cladding part so that long gas ducting means as in the said German patent publication 3,422,263 C2 are not required. 
     The gas generator may have a cylindrical outline and may have gas outlet openings on its external peripheral surface with the result that there is a rapid inflation operation. 
     It is preferred for the gas generator to extend in the longitudinal direction of the folded head gas bag along the middle third of the head gas bag at the most to increase the compactness of the protective device of the invention. 
     The protective device of the invention is, in accordance with a preferred embodiment, adapted to be attached on the roof frame using a mounting plate on which the gas generator and the head gas bag are pre-mounted. This means that the protective device can be supplied as a completely pre-mounted module able to be rapidly installed in a vehicle. 
     If the gas generator is mounted in the interior of the head gas bag, the attachment of the gas generator to the head gas bag is simplified. 
     Furthermore, the mounting plate may be arranged in the interior of the head gas bag. Preferably at least one part of a screw/nut connection for attachment of the side impact protective device is fixed to the mounting plate in a non-rotatable fashion. An opening must be present at the associated point in the head gas bag through which the shank of a screw may extend. If a screw is welded to the mounting plate, for instance at its head, then the screw shank will extend through the opening in the gas bag to the outside, where the mating nut may be screwed on for attachment of the side impact protective device. If on the contrary a nut is secured to the mounting plate, it is then possible to drive a screw from the outside into the nut. 
     Furthermore, it is in some circumstances dependent on vehicle geometry an advantage to provide an adapter plate outside of the head gas bag, the adapter plate being able to be connected with the mounting plate and, furthermore, to be locked on the roof frame. Assembly is simplified by the adapter plate, for it can extend to readily accessible parts in the roof frame part. 
     A particularly simple and secure attachment of the gas generator on the mounting plate is achieved in accordance with an advantageous embodiment if the mounting plate is designed in the form of a clip and engages around the gas generator. The diameter of the clip-like mounting plate is reduced by a clamping means, such means serving at the same time as the means for the attachment of the mounting plate so that there is a saving in parts. 
     The mounting plate may, furthermore, naturally also be arranged outside the head gas bag. 
     In order to hold the head gas bag during shipping in its folded condition, the same and the gas generator are pre-mounted on the mounting plate with the aid of a foil surrounding them or of a plastic tube. 
     If in accordance with a further preferred embodiment the cladding part is a door which is opened by the unfolding of the head gas bag and which is defined, as a possible measure, by intentional points of weakness in the cladding part, the unfolding operation will take place more rapidly and the direction of unfolding will be under full control, since the head gas bag will not have to provide any great forces for deformation of parts. 
     The door can contribute to setting and holding of the direction of unfolding of the head gas bag, if it is provided with a means for limiting its maximum opening angle, such means for instance comprise a tethering tape attached on the one hand to the door and on the other hand to the roof frame. 
     The geometry of the door and its maximum opening angle are preferably so adapted to the head gas bag that the door steers the unfolding direction of the gas bag to be oblique in relation to the side window and the head gas bag assumes a position in front of the side window. 
     Moreover, in accordance with a further embodiment, the cladding part is so attached to the roof frame that the head gas bag may move into a position between the cladding part and the roof frame during unfolding so that a fish mouth-like opening results. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The foregoing and other features of the present invention will become apparent to those skilled in the art to which the present invention relates upon reading the following description with reference to the accompanying drawings, wherein: 
     FIG. 1 shows the side impact protective device in accordance with the invention with the head gas bag not yet unfolded. 
     FIG. 2 shows the side impact protective device in accordance with FIG. 1 with the head gas bag unfolded. 
     FIG. 3 shows a cross sectional view taken through the side impact protective device of FIG. 1 in accordance with a first embodiment. 
     FIG. 4 shows a cross sectional view of a side impact protective device in accordance with a second embodiment in the unmounted condition. 
     FIG. 5 shows a longitudinal view of the side impact protective device in accordance with FIG.  4 . 
     FIG. 6 is a side elevation of the side impact protective device of the invention in accordance with a further embodiment with the head gas bag unfolded. 
     FIG. 7 is a cross sectional view of the side impact protective device taken on the line  7 — 7  in FIG.  6 . 
     FIG. 8 is a cross sectional view of the side impact protective device taken on the line  8 — 8  in FIG.  6 . 
    
    
     DESCRIPTION OF PREFERRED EMBODIMENT 
     In FIG. 1, a side impact protective device  1  is illustrated having a head gas bag  3  folded only in a longitudinally elongated or extended manner, said head gas bag being attached to a roof frame  5  of a vehicle above the door opening underneath a cladding part  17  which represents the ceiling of the vehicle interior. In order to render the drawing more clear, the cladding part  17  is shown as being omitted in FIGS. 1 and 2 adjacent to the side impact protective device  1 . The folded head gas bag  3  extends from the A column of the vehicle to the B column thereof and is secured at two points to the roof frame  5 , such points being at its two outer end portions  7  which are at the top in the unfolded condition, as is best seen in FIG.  2 . At such points, the head gas bag  3  has ears with attachment eyes through which there extend screws  15  illustrated in FIG. 2, said screws being able to be screwed into the roof frame  5 . A gas generator  11  extends in the longitudinal direction of the folded head gas bag  3  along approximately the middle third of the head gas bag  3  and is secured to the roof frame with the aid of a mounting plate  9 , as is clearly illustrated in FIG.  3 . 
     As shown in FIG. 3, the gas generator  11  which is arranged in the interior of the head gas bag  3  has a cylindrical outline with numerous gas outlet openings  33  distributed over its outer peripheral surface, such openings being directed toward a folded region of the head gas bag  3 . A male threaded stud  39  molded on the peripheral surface extends right through an opening in the head gas bag  3  to the outside and, furthermore, through an opening in a Y-shaped mounting plate  9 . A web of the mounting plate  9  to which the gas generator  11  is attached by its stud  39  and a nut  41  is adapted in its form to the outline of the gas generator  11  and surrounds same partly so that the gas generator  11  is thrust against the web of the mounting plate  9  on screwing up the nut  41  tight with the result that the opening in the head gas bag  3  is sealed off adjacent to the stud  39  in order to prevent escape of gas. openings are also provided in the other web of the Y-shaped mounting plate  9  through which screws  13  extend for the attachment of the side impact protective device  1  on the roof frame  5 . The side impact protective device  1  may be simply screwed on the roof frame  5  as a completely pre-assembled unit, such pre-assembly being performed on the one hand by using the studs  39  and on the other hand by using a foil  2  surrounding the mounting plate  9 , the folded head gas bag  3  and the gas generator  11 . The cladding part  17  underneath which the side impact protective device  1  is arranged without being visible from the outside is partially designed in the form of a door  19  or flap which is able to be opened by the unfolding of the head gas bag  3 . The door  19  is defined by a U-like line of intentional weakness  21  in the cladding part  17 . The edge of the door  19  which is pointed toward a vehicle door  31  is latched in a rail-like holding part  43  secured to the roof frame  5 . A device for limiting the maximum angle of opening of the door  19  in the form of a tether tape  27  is on the one hand secured to the door  19  and on the other hand by means of screws  23  to the roof frame  5 . The opened door  19  is indicated in FIG. 3 in chained lines. 
     FIG. 4 shows a second embodiment of the side impact protective device  1 ′, adapted to be pre-mounted as a complete unit, in the case of which the mounting plate  9 ′ as well is also arranged within the head gas bag  3 ′ since it extends like a clip about the gas generator  11 ′. A screw/nut connection, comprising a screw  37  and a nut  35 , serves on the one hand as a means for the attachment of the mounting plate  9 ′ on an adapter plate  29  located outside the head gas bag  3 ′, and on the other hand as a means for clamping the clip-like formed mounting plate  9 ′. For this purpose, the head of the screw  37  is welded to the mounting plate  9 ′. An associated screw shank extends right through an opening in the mounting plate  9 ′ and in the head gas bag  3 ′ to the outside and further through an opening in the adapter plate  29 . The mounting plate  9 ′ together with head gas bag  3 ′ is thrust against the adapter plate  29  by means of the nut  35  and fixed on the plate  29  with the result that the opening in the head gas bag  3 ′ does not permit any escape of gas therethrough. The adapter plate  29  and accordingly the entire side impact protective device  1 ′ is able to be screwed to the roof frame  5  by means of the screws  13 ′. In order to improve fitting and for facilitating shipping, a thin, slotted plastic tube  28  surrounds the folded head gas bag  3 ′ and accordingly the gas generator  11 ′ and partially also the adapter plate  29 . 
     FIG. 5 shows the head gas bag  3 ′ with partial sectioning at the mounting plate  9 ′ and at the gas generator  11 ′. In this case, it will be seen that the mounting plate  9 ′ and, furthermore, the adapter plate  29  do not extend laterally as far as the top end portions  7 ′ of the head gas bag  3 ′, but only as far as the side ends of the gas generator  11 ′. 
     The assembly of the side impact protective device  1 ,  1 ′ as a complete module takes place quite simply using the two screws  13 ,  13 ′ and by then driving the screws  15 ,  15 ′ through the attachment eyes into the roof frame  5 . 
     Since the head gas bag  3  is unfolded in the longitudinal direction, that is to say is already secured in and locked on the vehicle for its entire longitudinal extent, the position of the gas bag is stable in the unfolded state. Unfolding as such is commenced following a side impact by firing of the pyrotechnic material located in the gas generator  11  whereupon the gas will flow out of the gas generator  11  via the gas outlet openings  33  and will unfold the head gas bag  3 , whereupon the door  19  will fly out of the holding part  43  and will fold so far toward the middle of the vehicle as is permitted by the tether tape  27 . The geometry of the door  19  and the maximum opening angle thereof are so matched to the head gas bag  3  that the door  19  will steer the direction of unfolding of the head gas bag  3  obliquely toward a side window  25 . Once the head gas bag  3  is completely unfolded, an intermediate space between the opened door  19  and the side window  25  will be occupied by the head gas bag  3 . The head gas bag  3  will extend immediately adjacent to the side window  25  downwardly and is partially supported by the same. The head gas bag  3  itself can unfold principally only downwardly in the longitudinal direction and toward the head of a vehicle occupant owing to its fixed position in the longitudinal direction with the result that a rapid, fully controlled unfolding action will ensue. The door  19  is extremely narrow in design and will hardly project inward at all in its pivoted open setting in order not to present any danger to the head of the vehicle occupant. 
     Instead of the door  19 , the cladding part  17 ″ may, as shown in FIGS. 6 through 8, be so secured to the roof frame  5 ″ that the head gas bag  3 ″ moves through between the same and the roof frame  5 ″ in the course of unfolding and, accordingly, produces an aperture like the mouth of a fish. For this purpose, the cladding part  17 ″ is secured to the roof frame  5 ″ using the holding part  43 ″. The cladding  17 ″ comes clear of the holding part  43 ″ as is illustrated in FIGS. 7 and 8 during unfolding of the head gas bag  3 ″ and does, however, remain secured to the roof frame  5 ″ by way of the holding part  43 ″ in the part past the end portions  7 ″. The cladding part  17 ″ bulges somewhat inwardly so that a wider slot is produced in the middle of the head gas bag  3 ″ through which the head gas bag  3 ″ may slip. In the case of this embodiment, no additional tear-open means are required. 
     From the above description of the invention, those skilled in the art will perceive improvements, changes and modifications. Such improvements, changes and modifications within the skill of the art are intended to be covered by the appended claims.