Abstract:
The invention relates to a vehicle steering wheel, comprising a steering wheel skeleton encased in foam and consisting of a steering wheel rim, a hub and at least one spoke connecting the hub with the steering wheel rim. The steering wheel further comprises a panel which is visible from outside on the steering wheel rim. A clip is provided which is constructed as a separate part and engages on the steering wheel rim. the panel is fastened to the steering wheel rim by means of the at least one clip and the panel together with the clip completely surround the steering wheel rim.

Description:
TECHNICAL FIELD 
     The invention relates to a vehicle steering wheel. 
     BACKGROUND OF THE INVENTION 
     Steering wheels having an expensive appearance increasingly have a panel or cover of hard material, visible from outside, on the steering wheel rim, preferably on the inner face of the steering wheel rim facing the hub. Such panels generally have on their outer face an imitation of wood, which is intended to give the steering wheel a higher-quality appearance. The fastening of such panels to the steering wheel is complicated and expensive. The embedding of the panel into the foam casing of the steering wheel rim or the direct attachment on the steering wheel skeleton, more precisely on the steering wheel rim of the steering wheel skeleton, are provided as fastening possibilities. 
     BRIEF SUMMARY OF THE INVENTION 
     The invention provides a vehicle steering wheel in which the fastening of the panel can take place quickly, simply and at a favorable cost. This is achieved in a vehicle steering wheel which comprises a steering wheel skeleton encased in foam and consisting of a steering wheel rim, a hub and at least one spoke connecting the hub with the steering wheel rim. The steering wheel further comprises a panel which is visible from outside on the steering wheel rim. A clip is provided which is constructed as a separate part and engages on the steering wheel rim. The panel is fastened to the steering wheel rim by means of the at least one clip, and the panel together with the clip completely surround the steering wheel rim. The panel and the clip form a unit which fully embraces the steering wheel rim in the circumferential direction, seen in a cross-sectional view through the rim. In steering wheels known hitherto, the steering wheel skeletons had to be coordinated with the fastening of the panel, which made the skeleton more complicated in its construction. In the steering wheel according to the invention, on the other hand, the clip is a separate part which is only fastened to the steering wheel skeleton when required and in addition can be positioned at various points. Through the use of the clip, a greater flexibility is achieved in the production of different steering wheels with and without a panel, or with various panels. In addition, it is possible through the flexible clip to hold the clips on the steering wheel skeleton and/or the panel on the clip permanently with pre-stressing, so that a loosening of the parts from each other or a vibrating after several years of driving operation can be avoided which is achieved by the panel and the clip completely surrounding the steering wheel rim. 
     Preferably, the panel and the clip are connected with each other by means of a clip connection, i.e. a very simple type of fastening which requires little installation time. 
     The clip can embrace the steering wheel rim and is thereby securely positioned. For example, provision is made for this that the clip, according to a preferred embodiment, has a C-shaped cross-sectional profile. The panel can engage on the outer or inner face on the free edges, lying opposite each other. Through the C-shaped profile with the free edges, the clip achieves a sufficiently high flexibility in order to realize the desired clip connection 
     Hook-shaped extensions on the panel engage behind the free edges, in accordance with the preferred embodiment, to provide a secure connection. 
     According to another development of the invention, the panel presses the free edges towards each other so that it endeavors to close the clip which is open in cross-section. The clip and panel thereby reciprocally secure each other on the steering wheel skeleton. 
     The clip is of course also encased in foam, the panel, the clip and the foam casing being coordinated with each other such that with the steering wheel encased in foam, the panel can be clipped onto the clip from outside. Preferably, this clipping on should still be possible even after a covering of the steering wheel with leather, if a covering with leather takes place at all, in order to avoid the panel having to be integrated into the process of encasing in foam. 
     The clip can in addition have a dual function by on the one hand arresting the panel and on the other hand arresting an additional mass on the steering wheel rim. Separate additional masses, fastened at desired sites on the steering wheel rim, are intended to increase the inert mass of the vehicle steering wheel as a whole and to largely prevent vibrations. 
     Between the clip and the steering wheel rim, a form-fitting connection can also be provided, so that the positions of the parts to each other are fixed. This prevents faulty installations. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 shows a top view onto a diagrammatically illustrated steering wheel skeleton according to the invention, with several clips, 
     FIG. 2 shows a cross-section through a steering wheel rim, encased in foam and covered with leather, of a steering wheel according to the invention, in accordance with a first embodiment, 
     FIG. 3 shows a cross-section through a steering wheel rim, encased in foam and covered with leather, of the steering wheel according to the invention, in accordance with a second embodiment, 
     FIG. 4 shows a cross-section through a steering wheel rim, encased in foam and covered with leather, of a steering wheel according to the invention, in accordance with a third embodiment. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     In FIG. 1 a steering wheel skeleton is illustrated, consisting of a steering wheel rim  3 , a steering wheel hub  5  and several spokes  7  connecting the steering wheel rim  3  with the steering wheel hub  5 . Several additional masses are arranged on the periphery of the steering wheel rim  3 , uniformly distributed, to increase the inertia of the steering wheel and hence to reduce the vibrations in driving operation. The additional masses can be seen in the following figures; in FIG. 1 only clips  9  are visible, which serve inter alia for arresting the additional masses on the steering wheel rim  3 . 
     In FIG. 2, which is a greatly enlarged view through a steering wheel in the region of the steering wheel rim, the steering wheel rim  3  of the skeleton is illustrated as an open hollow profile. The hollow profile is open to the rear face of the steering wheel (at the bottom in the drawings). From this side, an additional mass  11  is inserted into the hollow profile. The additional mass is adapted in its shape to the inner face of the hollow profile, so that no transverse movements can occur between the steering wheel rim  3  and the additional mass  11 . The additional mass of forged steel is accommodated almost completely inside the steering wheel rim  3 . Only two lateral extensions  13  surround the free edges  15  of the steering wheel rim  3  and serve for the additional fixing of the additional mass  11  on the steering wheel rim  3 . The arresting of the additional mass  11  on the steering wheel rim  3  takes place by a clip  9  bent in a C-shape, which can be clipped from outside onto the steering wheel rim  3  which is not yet encased in foam and not yet covered with leather. The clip is formed from a wide spring steel band and presses the additional mass  11  under prestressing into the interior of the steering wheel rim  3 . So that the steering wheel rim  3  is positioned exactly to the clip  9  and the latter is exactly positioned to the additional mass  11 , and so that the sites on the periphery of the steering wheel rim  3  on which the additional mass  11  is to be fastened are preset, form-fitting connections are provided between steering wheel rim  3  and clip  9  and also between clip  9  and additional mass  11 . The form-fitting connections are each formed by at least one projection  17  on the front face of the steering wheel rim  3  and one projection  19  on the additional mass  11  and also by recesses  21  and  23  in the clip  9 , into which the projections  17  and  19 , respectively, project. The projections  17  can also be seen in FIG.  1 . 
     The illustrated steering wheel which has a high-quality appearance, has externally visible panels  25  of plastic, composite material, aluminum, wood or of another suitable material, which panels have for example on the exterior an imitation of wood. A panel  25  of plastic, arranged on the inner face of the steering wheel rim, is shown in FIG.  2 . On the periphery of the steering wheel rim, on the inner face, a panel  25  sits in the region of each clip  9 , which panel  25  covers on the inner face a segment of the steering wheel rim, the latter encased in foam. The panel  25  has outer edges  27 , which are directed towards each other. These edges  27  each engage an associated, outwardly bent edge  29  of the clip  9 . Thereby, a form-fitting clip connection is produced between the free edges  29  of the clip  9  and the edges  27  of the panel  25 . The panel  25  endeavors to press the edges  29  together and serves as additional arresting of the clip  9 . The clip  9  is pressed in a prestressed manner against the steering wheel rim. The clip  9  in turn serves for arresting the panel  25 , because the panel  25  does not require an additional means for its arresting on the steering wheel rim. 
     As can be seen in addition from FIG. 2, the shape of the clip  9  is largely adapted to the outer contour of the steering wheel rim  3  and also to the additional mass  11 , so that an extensive abutment of the clip  9  is produced against the steering wheel rim  3  on the front face and against the additional mass  11  on he rear face. Further, it can be seen from FIG. 2 that the panel together with the clip completely surrounds the steering wheel rim in the circumferential direction in those sections of the rim where both panels and clips are provided. 
     The steering wheel rim  3  together with the clips and the additional masses  11  arranged thereon is surrounded by a foamed casing  31 , adjoining which on the outer face is a leather covering  33 . The leather covering  33  has ends  35  towards the panel  25 , which ends  35  are deflected into the interior of the foam casing of the steering wheel rim. 
     The production of the illustrated steering wheel is explained in detail hereinbelow. After the production of the steering wheel skeleton, the additional masses  11  are fastened by means of the clips  9  to the sites marked by the projections  17 . Here, firstly, each additional mass  11  is pressed into the hollow interior of the steering wheel rim  3 . Then the clip  9  is placed in position, the projections  17 ,  19  engaging into their recesses  21  and  23 , respectively. Then the steering wheel is encased in foam and covered with leather. Finally, the panels  25  are inserted from the inner face of the steering wheel rim, the edges  27 ,  29  forming a latching connection, for which reason the panels only have to be clipped onto the clips. 
     The embodiment illustrated in FIG. 3 corresponds substantially to the one previously discussed, with the parts already discussed having the reference numbers already introduced, increased by the number 100. In contrast to the embodiment shown in FIG. 2, the additional mass  111  is accommodated completely inside the hollow interior of the steering wheel rim  103 . It can also be pushed completely into this hollow interior. So that the flexible clip  109  lies with a prestressing against the additional mass  111 , it has a projection  141 , by which it contacts the additional mass  111 . A further projection  143  serves to provide a prestressing in a transverse direction. In this embodiment, the clip  109  is provided with edges  129  which are bent towards each other. The panel  125  in turn has hook-shaped extensions  151  which engage behind the free edges  129 . With the clip  109  inserted, the edges  129  are pressed away from each other. 
     The embodiment illustrated in FIG. 4 corresponds substantially to that shown in FIG.  3  and already discussed. Here, also, the reference numbers which have already been used are used again, however again increased by the number 100. In contrast to the embodiment shown in FIG. 3, the clip  209 , which is surrounded by foam  231 , embraces the steering wheel rim  203  still more, so that it engages more securely on the steering wheel rim  203 , with the additional mass  211 , of the skeleton. In this embodiment, the clip has edges  229  which are bent outwards more intensively and which engage behind the hook shaped extensions  251  of the panel  225  and press them towards each other.