Abstract:
A process and a device for reinforcing a convertible soft top ( 34 ) or the like, especially for motor vehicle convertible tops, the convertible soft top ( 34 ) being entirely or partially underlain with reinforcing components (bow  32 ). At least one reinforcing component (bow  32 ) is molded directly onto the convertible soft top ( 34 ) in an injection mold ( 24 ). For the case in which the convertible soft top ( 34 ) is not to be joined over its entire surface to the reinforcing component (bow  32 ), the part of the convertible soft top ( 34 ) which is not to be connected to the reinforcing component is routed out of the casting mold ( 24 ) via a branch channel ( 36 ).

Description:
BACKGROUND OF THE INVENTION  
         [0001]    1. Field of the Invention  
           [0002]    This invention relates to a process and a device for reinforcing a convertible soft top or the like, especially for motor vehicle convertible tops, the convertible soft top being entirely or partially underlain with reinforcing components.  
           [0003]    2. Description of Related Art  
           [0004]    Reinforcing components are used not only to support and shape convertible soft tops, but also for acoustic and thermal insulation of the convertible top. Examples of these reinforcing components are the bows of folding-and-sliding roofs guided in side guide rails or also large area, plate-like components in modern convertible tops (for example, RHT—retractable hard top).  
           [0005]    In conventional convertible top systems, these reinforcing components are cemented under the convertible soft top or sealed to it. In doing so, generally aesthetically less attractive impressed areas or sunken spots in the region of these components are formed. Moreover, these adhesive or sealed connections have often proven less resistant so that the reinforcing components, after longer use, have detached in whole or in part from the convertible soft top. Another disadvantage of the known process is that the production of the reinforcing components and their joining to the convertible soft top are separate working steps so that the production process is relatively complex.  
         SUMMARY OF THE INVENTION  
         [0006]    A primary object of this invention is to devise a process and a device for reinforcing a convertible soft top or the like which enable good and permanent connection of the reinforcing components to the convertible soft top, which furthermore ensure a good support function and an aesthetically pleasing outer appearance of the convertible top without impressed areas and sunken spots, and which allow production which is more economical compared to the conventional process.  
           [0007]    This object is achieved in accordance with the invention in that the reinforcing components are molded directly onto the convertible soft top in an injection mold. It has been found that, in this way, a good permanent connection between the convertible soft top and the reinforcing components is achieved, the transition from the reinforced areas to the unreinforced areas being configured such that impressed areas and sunken spots are avoided. In addition, the production process becomes more economical overall due to the formation of the reinforcing components and their joining to the convertible soft top taking place in a single working process.  
           [0008]    In the process of the invention, it is provided that the convertible soft top which is to be reinforced is inserted into a plastic casting mold which corresponds essentially to the shape of the reinforcing component, so that it borders the mold cavity for forming the reinforcing component, and that the reinforcing component is injected then directly onto the convertible soft top in the casting mold by injection of a suitable plastic material. After setting of the plastic material, the finished convertible top can be removed from the casting mold.  
           [0009]    In one preferred embodiment of the process, it is provided that the plastic material is a foam. These foam materials have relatively good strength properties, good stability of shape and outstanding acoustic and thermal insulation properties.  
           [0010]    In many cases, the reinforcing component is connected only over one part of its surface facing the convertible soft top to the latter because, for example, the convertible soft top, when the convertible top is opening, will form a loop at this point. For such a case, it is provided, in accordance with the invention, that the part of the convertible soft top which is not to be connected to the reinforcing component is routed, for the molding-on process, via a branch channel away from the mold cavity, and for example, out of the casting mold.  
           [0011]    For the case in which the convertible soft top, in the area of the reinforcing component, is intended to pass into a doubled convertible soft top, according to another embodiment of the invention, it is provided that the upper layer of the doubled convertible soft top is routed out of the casting mold via a branch channel.  
           [0012]    A device for executing the process of the invention is characterized in that the casting mold is divided at least in the plane of the inserted convertible soft top into a top mold which supports the convertible soft top and a bottom mold which has the mold cavity for forming the reinforcing component. The plane of separation between the top mold and the bottom mold is essentially the plane which is defined by the convertible soft top.  
           [0013]    The branch channels which are used for routing the convertible soft top out of the casting mold are made in the top mold according to another embodiment of the invention, i.e., the branch channels each continue from the mold cavity for forming the reinforcing component.  
           [0014]    A further simplification of the casting mold arises when the top mold is divided once more in the area of the branch channel, the dividing joint being made as a branch channel.  
           [0015]    Several embodiments of the invention are shown in the drawings and are explained in detail below. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0016]    [0016]FIG. 1 is a schematic perspective view a motor vehicle with a folding-and-sliding roof;  
         [0017]    [0017]FIG. 2 is a partial section through the folding-and-sliding roof of FIG. 1 roughly corresponding to section line II-II;  
         [0018]    [0018]FIG. 3 shows a casting mold for full-surface joining of a bow to the convertible soft top;  
         [0019]    [0019]FIG. 4 shows a casting mold for partial-surface joining of a bow to the convertible soft top;  
         [0020]    [0020]FIG. 5 shows a casting mold of a doubled convertible soft top with a bow. 
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0021]    [0021]FIG. 1 shows a motor vehicle  2  with a folding-and-sliding roof  4  for selectively opening and closing a roof cutout  6 . The folding-and-sliding roof  4  comprises, essentially, a flexible convertible soft top  8  which is connected to several (in the example 4) bows  10  which are guided in lateral guide rails. To open the folding-and sliding roof  4 , the bows  10  are pushed to the rear, the convertible soft top  8  forming loops which project upward, as is generally known.  
         [0022]    [0022]FIG. 2 shows a section roughly corresponding to the section line II in FIG. 1, however, the convertible soft top  8  not being stretched, as corresponds to the closed state of the folding-and sliding roof  4  shown in FIG. 1, but instead forms a loop which projects upward when the folding-and sliding roof  4  is opening, i.e., when adjacent bows  10  are pushed together. FIG. 2 further shows that the convertible soft top  8  is not connected over its entire surface, i.e., over the entire width t of the bow  10 , but only over a range a; this enables larger, less sharply bent loops between the individual bows  10 . The bow  10  is made as an essentially flat strip  10   a  with reinforced lengthwise ribs  10   b  on its bottom.  
         [0023]    [0023]FIG. 3 schematically shows a casting mold  12  for molding the bow  14  to the convertible soft top  16 . The bow  14  is shown in cross section, as in FIG. 2. The mold  12  encompasses a top mold part  18  and a bottom mold part  20 . The bottom mold part  20  has a mold cavity  22  for forming the bow  14 . The bow  14  in turn, as in the example from FIG. 2, has the shape of a flat strip with lengthwise reinforcing ribs formed on its bottom. The bottom mold part  20  is, moreover, provided with injection channels for injecting the plastic material which forms the bow  14  in the conventional manner which is therefore not detailed.  
         [0024]    In order to join the convertible soft top  16  to the bow  14 , the convertible soft top is inserted into the casting mold  12 , the mold is closed, and then the plastic material which forms the bow  14  is injected, its being intimately joined to the convertible soft top  16 . In doing so, the transitions from the reinforced areas to the nonreinforced areas of the convertible soft top can be made such that impressed areas and sunken spots do not occur. As was already stated above, the plastic material is preferably a foam material so that the injection process can also be called a foaming-on process.  
         [0025]    [0025]FIG. 4 shows a casting mold  24  which has a top mold part  26  and a bottom mold part  28 . The bottom mold part  28  has a mold cavity  30  for forming a bow  32 . The bow  32 , in turn, has the shape of a flat strip with lengthwise ribs formed on its bottom. The convertible soft top  34  is to be joined to the bow  32  as in the example of FIG. 2, however, only over the width range a. For this purpose, part of the convertible soft top  34 , i.e., the part which is not to be connected to the bow  32 , is routed out of the casting mold  24  via a branch channel  36  which is made in the top mold  26 . As indicated in FIG. 4, the top mold part  26 , in the area of the branch channel  36  is divided into a fixed mold part  26   a  and a slide-like mold part  26   b  which can be moved in the directions of the double-arrow  38 , the dividing joint between the mold part  26   a  and the mold part  26   b  forming the branch channel  36 .  
         [0026]    In order join the convertible soft top  34  to the bow  32  in the manner shown in FIG. 4, for example, the convertible soft top  34  is placed on the bottom mold part  28 . Then, the mold part  26   a  is placed on the bottom mold part  28  and the convertible soft top is guided upward along the lower edge of the mold part  26   a  to the outside. Then, the mold part  26   b  is inserted, the joint of separation between the mold part  26   a  and the mold part  26   b  forming the branch channel  36 . Then, the plastic material is injected for forming the bow  32 . After curing of the bow  32 , the mold part  26   b  is slid into the open position and the mold part  26   a  is lifted off the bottom mold  28  so that the component comprising the convertible soft top  34  and the bow  32  can be removed.  
         [0027]    [0027]FIG. 5 shows a casting mold  40  which comprises a top mold part  42  and a bottom mold part  44 . The top mold part  42 , as in the example in FIG. 4, is divided into a fixed mold part  42   a  and a movable, slide-like mold part  42   b  which can be pushed in the direction of the double-arrow  46 . In the bottom mold part  44 , a mold cavity  48  is made for forming a bow  50 . Between the fixed mold part  42   a  and the movable mold part  42   b , a branch channel  52  is formed via which the part of the first convertible soft top  34  which is not to be connected to the bow  50  can be routed out of the casting mold  40 , as was explained relative to the example of FIG. 3. As FIG. 5 indicates, the bottom mold  44 , on the one hand, and the mold part  42   b  of the top mold  42 , on the other hand, are made such that a space remains between them for inserting a second convertible soft top  56  which is cemented to the first convertible soft top  54  in the area of the middle of the bow. In the part which is on the right in FIG. 5, accordingly, the convertible soft top is made doubled in the manner necessary for certain applications (first convertible soft top  54 , second convertible soft top  56 ).  
         [0028]    It should be pointed out here that FIGS.  3  to  5  show certain embodiments to which the invention is however not limited. Thus, for example, a casting mold can have several mold cavities for forming several or all bows of a folding-and-sliding roof, the areas of the convertible soft top which lie between the bows being guided out of the casting mold via suitable branch channels. Moreover other reinforcing components can be molded to the convertible soft top, can support large surface areas of the convertible soft top and leave exposed only small areas which are necessary for bending or folding the convertible top, as need not be explained in detail here.