Abstract:
A convertible includes an automobile body and a movable roof having at least a rear roof part and an upper roof part, wherein the rear roof part extends at least between a belt line and the upper roof part. The upper roof part is located above a passenger compartment and in front of the rear roof part. The rear roof part has a middle section that encloses a rear window and is located between lateral main posts of the automobile body when the roof is closed. The main posts and the middle section are each rotationally connected with the automobile body and with the upper roof part by joints which form a multijoint linkage whose axis of rotation lie in a common plane in at least one movement position of the roof, so that at least one additional support of the upper roof part located in front of the rear roof part is provided for supporting the upper roof part with respect to the automobile body, wherein the additional support is active in the at least one movement position of the roof.

Description:
BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   The invention concerns a convertible and a movable roof for the convertible 
   2. Description of the Related Art 
   DE 44 45 580 C1 describes a convertible that has rigid roof parts that can be folded towards each other. A rear roof part comprises two main posts that project laterally upward and a rear window that lies between them. Following the course of the main posts, two parts of a linkage are installed on each side of the vehicle, one so-called link and one main link, which extend between a main bearing situated below the belt line and a front roof part, which, in its closed position, lies essentially horizontally above the passenger compartment. The link and the main link lie essentially parallel to each other in a side view and form parts of an articulated parallelogram, with which the opening and closing movement of the roof parts can be effected. 
   The main link can also be formed by the main post of the rear roof part itself. However, at least the link lying parallel to this juts out in any case relative to the rear roof part and thus limits the head clearance in the passenger compartment—as is also the case with an upper horizontal link (referred to there as guide element  15 ), which is arranged below the front roof part and connects the link and the main link with each other to close the parallelogram. Precisely in the case of two-seater vehicles, in which the head of the driver or passenger must be held in the vicinity of the transition between the front and rear roof parts, linkage parts arranged there are especially troublesome and, in the event of an accident, dangerous. Therefore, it is necessary to provide additional lining elements for these linkage parts. These additional lining elements further reduce interior space and, of course, also allow the linkage parts to pass through slot recesses or the like during movement of the roof. 
   SUMMARY OF THE INVENTION 
   The invention is based on the problem of creating optimized folding kinematics in a convertible with several rigid roof parts. 
   The invention solves this problem with a convertible that includes at least two rigid roof parts, wherein a rear roof part extends at least between the belt line and a roof part, which is located above a passenger compartment and in front of the rear roof part, and the rear roof part has a middle section that encloses a rear window and is located between lateral main posts when the roof is closed, characterized by the fact that the main posts, on the one hand, and the middle section, on the other hand, are each separately rotationally connected both with the automobile body and with the upper roof part by joints, which form a multijoint linkage as seen in a side view, and whose axes of rotation lie in a common plane in at least one movement position of the roof, such that at least one additional support of the roof part or a roof part located in front of the rear roof part is provided for supporting the roof part with respect to the automobile body and is active in at least this movement position of the roof. 
   In accordance with the invention the individual pivot connection of the middle section, which encloses the rear window, on both the automobile body and the upper roof part makes it possible for the middle section that encloses the rear window to act as a pivot link, and therefore the number of additional links can be reduced or, especially advantageously, can be dispensed with entirely. This applies both to links that extend parallel to the main posts and to an upper horizontal connecting piece. This increases head clearance and reduces the risk of injury. 
   In particular, if both the main posts and the middle section can act as pivot links between the automobile body and the upper roof part, a pair of pivot links is already formed on each side of the vehicle, which makes it possible to realize advantageous roof lowering kinematics, even without additional links. Due to the individual swivelability of the middle section, on the one hand, and of the lateral main posts, on the other hand, the roof lowering movement can be adapted to the space conditions in the automobile body, since in the lowered position, the specified parts can be spaced apart from one another. 
   In the design in accordance with claim  3 , the use of the middle section and the main posts as parts of an articulated parallelogram makes it possible to preserve the simple and unobstructed movement of the roof by means of an articulated parallelogram, and the aforementioned advantages can be realized at the same time. 
   If the middle section and the main posts are connected with each other by a coupling element that synchronizes their pivoting movements, a tilt-free course of the opening movement is further supported. 
   It is very advantageous for the rear window to lie above the lateral main posts when the roof is in its opened state, so that the space available for holding luggage below the rear window is increased. 
   Especially good visibility to the rear can be realized if the middle section consists of a transparent rear window over essentially its entire height. 
   The outdoor feeling can be further improved, even when the roof is closed, if a panel that acts as a sunroof is assigned to the upper roof part. This panel can be opened by moving it over the rear roof part. It is especially useful for the panel also to be transparent. 

   
     BRIEF DESCRIPTION OF THE DRAWING 
     Other advantages and features of the invention are apparent from specific embodiments of the object of the invention, which are illustrated in the drawings and described below. 
       FIG. 1  shows a convertible of the invention in a schematic side view that is broken off below and at the front, with the roof closed and the panel of the upper roof part closed. 
       FIG. 2  shows, in a view similar to that of  FIG. 1 , an alternative design with a single-piece upper roof part without a separate sunroof. 
       FIG. 3  shows a view similar to that of  FIG. 1  during the opening of the panel that acts as a sunroof, which additionally shows the drive and reduction gear train for moving the roof parts. 
       FIG. 4  shows a view similar to that of  FIG. 3  with the panel it its completely opened position and with the roof otherwise closed. 
       FIG. 5  shows the roof in the embodiment according to  FIG. 2 , in which there is no sunroof, during the opening of the roof. 
       FIG. 5   a  shows, in a view similar to that of  FIG. 5 , the embodiment with the sunroof, with the sunroof in its open position. 
       FIG. 6  shows a view similar to that of  FIG. 5   a  with further progression of the opening of the roof. 
       FIG. 7  shows the roof of  FIG. 6  in its completely opened position, in which it is lowered into the rear end of the vehicle. 
       FIG. 8  shows a perspective exploded view of the roof with the plate section provided in the upper roof part. 
       FIGS. 9 to 12  show a simplified systematic side view of the moving parts critical to the lowering of the roof without consideration of drives, gears or a sunroof. 
       FIG. 9  shows the roof kinematics in the closed roof position. 
       FIG. 10  shows the roof kinematics in the first opening phase, corresponding approximately to the opening position shown in  FIG. 5 . 
       FIG. 11  shows the roof kinematics in the opening position, corresponding approximately to the opening position shown in  FIG. 6 . 
       FIG. 12  shows the roof kinematics in the completely open position, corresponding to  FIG. 7 . 
       FIG. 13  shows a view similar to that of  FIG. 1  with the roof as a whole displaced horizontally to the rear to release the catch between the front end of the roof and the windshield frame. 
   

   DETAILED DESCRIPTION OF THE INVENTION 
   The illustrated convertible in accordance with the invention is a two-seater. A convertible with, say, two rows of seats one behind the other can also be constructed in accordance with the invention. 
   The vehicle  1  comprises a movable roof, which is labeled as a whole with  2 . The roof  2  comprises a rear roof part  3 , i.e., a roof part that is located at the rear relative to the direction of travel F, with two lateral main posts  4  and a middle section  5  located between them. The middle section comprises or is essentially formed by a flexible or, especially, rigid rear window  6 , which can be made, for example, of plastic or, advantageously, glass. Both the main posts  4  and the middle section  5  are rigid and therefore can transmit torques. The main posts  4  and a possible frame  5   a  of the middle section  5  can be made, for example, of steel, a light metal, a metallic foam material, or plastic. It is also possible for the main posts  4  to be transparent. Moreover, the main posts  4  can be supported by frame parts. 
   In addition, the roof  2  comprises an upper roof part  7 , which, in the closed state, is arranged in front of the rear roof part  3  in the direction of travel F of the vehicle. In the illustrated embodiment with a two-seat vehicle  1 , this upper roof part  7  is formed by a single panel without further transverse division. In the closed state, it is directly or indirectly supported on the windshield frame  8 . Like the main posts  4 , the upper roof part  7  can be made of various materials. 
   The main posts  4  are supported in their lower region by arms  9   a  relative to the automobile body  20  on pivot bearings  9 , which are fixed with respect to the automobile body at least during the swiveling. Their bearing axes run horizontally and transversely to the vehicle  1 . In their upper region, the main posts  4  are connected with the upper roof part  7 , which is situated above a passenger compartment, on pivot joints  10 , which also have horizontal bearing axes that extend transversely to the vehicle  1 . When the roof is being opened, the roof parts  3  and  7  fold towards each other about the axis of the pivot joints  10 . 
   The lower region of the middle section  5  is supported by arms  11   a  relative to the automobile body  20  on one or more pivot bearings  11 , which are fixed with respect to the automobile body at least during the swiveling. Their bearing axes run horizontally and transversely to the vehicle  1 . In its upper region, the middle section  5  is connected with the upper roof part  7  on at least one pivot joint  12 , which likewise has a horizontal bearing axis that extends transversely to the vehicle  1 . In the present embodiment, two pivot joints  12  are provided, which are assigned to each side of the vehicle  1 . 
   The pivot joints  11  and  12  of the middle section  5  each lie in planes above the planes of the pivot joints  9  and  10  of the lateral main posts  4 . As will be explained in greater detail below, the pivot bearings  9  and  11  can optionally be fixed with respect to the automobile body during the swiveling but can be displaced horizontally or almost horizontally between a closed roof position ( FIG. 1 ) and an extreme rearward position suitable for swiveling ( FIG. 13 ). 
   As an additional option, in one illustrated embodiment, the front roof part  7  additionally comprises a displaceable panel  13 , which can be opened like a sunroof and displaced over the rear roof part  3  ( FIGS. 3 ,  4 ,  5   a ,  6 ,  7 ,  8 ). The panel  13  is made of a transparent plastic or glass, so that even when it has been moved over the rear window  6 , the view to the rear is not obstructed. It has lateral arms  14 , which engage lateral guideways  16  of the upper roof part  7  by means of bearing journals  15  or similar guide elements. In addition, guide rails  17  are provided on the middle section  5  of the rear roof part  3  ( FIG. 8 ), which guide the panel  13  into a position parallel to the rear window  6  and can hold it there. In the closed position, the panel  13  engages both the guideways  16  by means of the arms  14  arranged in the front region and the rear guide rails  17  by means of other arms (not shown). Therefore, the roof  2  cannot be opened until the sunroof  13  has been opened. 
   Even in the open position of the panel  13  that acts as a sunroof, in which it is displaced to the rear by the maximum amount, the panel  13  is still held in the guide rails  17  of the rear roof part  3  and, by means of its arms  14 , in the guideways  16  of the upper roof part  7 . The end point of the guideways  16  lies on the pivot axis of the upper pivot joint  12 , with which the middle section  5  engages the upper roof part  7 , which makes it possible for the roof  2  to be opened and closed with the sunroof  13  open (see, e.g.,  FIG. 5   a ). A program control can be provided, which ensures that the roof  2  can be opened or closed only with the sunroof  13  completely open. Due to the fact that the sunroof  13  remains with both its front arms and its rear arms in the respective guides  16 ,  17 , it is not necessary to overcome any step during the opening of the sunroof  13 . Therefore, the opening operation can be carried out especially smoothly and reliably, even after an extended vehicle life. 
   Alternatively, it would also be possible for the panel  13  to be held in its closed state only on the upper roof part  7  and in its open state to be transferred completely to the rear roof part  3 . It would then be possible to open the roof with the sunroof  13  either completely open or completely closed. 
   In the illustrated embodiment, the middle section  5  consists of a support frame  5   a  and a transparent panel mounted on it, which serves as the rear window  6 . This panel can possibly support the guide rails  17  for the sunroof  13 . Many other designs are also possible, possibly also with a frame, in the middle of which the rear window is situated, or with arms  11   a  welded directly onto a rear window. 
   To secure the front roof part  7  on the windshield frame  8 , pins  18  are assigned to the roof part  7 , which are located approximately in its extension plane and are directed in travel direction F in the closed state of the roof. The pins  18  fit into complementary recesses  19  of the windshield frame  8 . The pins  18  and the recesses  19  can be conically shaped to facilitate centering of the closing roof  2 . An additional securing mechanism is not absolutely necessary if a securing mechanism of the displaceable main bearing  21  explained in the next paragraph is provided. 
   In the aforementioned optional design, the pivot bearings  9 ,  11  for the parts  4 ,  5  are fixed with respect to the automobile body and are mounted as a whole in a lateral main bearing  21 , which can be displaced relative to the automobile body  20  horizontally or almost horizontally in the longitudinal direction of the vehicle. A drive mechanism  22 , say, a hydraulic cylinder, a shaft, an electric motor or the like, is assigned to each of these main bearings  21 . Each of the main bearings  21 —and thus the roof  2  supported on them—can be moved by this drive mechanism  22  horizontally in the direction of arrow H (transition from  FIG. 1  to  FIG. 13 ) between a front extreme position with the roof completely closed and a rear extreme position ( FIG. 13 ), in which the roof  2  has been displaced in the direction opposite the direction of travel F to such an extent that the pins  18  have come out of the recesses  19  of the windshield frame  8 . In this position, the roof  2  can swivel freely about the bearings  21  without there being any danger of the tip of the roof colliding with the windshield frame  8 . 
   The distance between the front and rear extreme positions of the drive mechanism  24  is limited to a few centimeters by a possibly adjustable rear stop in such a way that in the rear extreme position of the roof  2 , the pins  18  are pulled out of the windshield frame  8  just far enough to allow swiveling to occur. Displacement too far to the rear, on the other hand, would unnecessarily delay the opening or closing operation. 
   The roof parts  3 ,  7  are coupled with each other by a coupling element  23  for their movement about the main bearings  21 , which are mounted laterally in the automobile body  20 . The coupling element  23  extends between arms  9   a  and  11   a , which connect the pivot bearing  9  with a main post  4  and the pivot bearing  11  with the middle section  5 . Therefore, one drive  24  for each side of the vehicle ( FIG. 3 ) is sufficient for producing a uniform swiveling movement about the bearings  9  and  11 . 
   To open the roof  2  from the closed position ( FIG. 1  for a version with a sunroof or  FIG. 2  for a vehicle without a sunroof) to a completely open position (FIG.  7 )—without the option of the roof  2  that can be moved as a whole—the arms  9   a  and  11   a  are first simultaneously swiveled by the force of the drive  24  ( FIG. 3 ) towards the rear about the bearings  9 ,  11 , which are fixed with respect to the automobile body ( FIG. 5  to  FIG. 7 , with  FIG. 5  showing a roof  2  without a sunroof  13 ). In the version with a sunroof, the sunroof  13  must be completely open during the opening of the roof  2 . In the example shown here, before the operation of opening the roof is started, the sunroof  13  is first opened by guiding the arms  14  in the guideways  16  and further guiding the panel  13  in the guide rails  17  of the rear roof part  3  in such a way that in the completely open position of the sunroof, the bearing journals  15  are coaxial with the pivot axis of the pivot joint  12  ( FIG. 4 , ff.). In this process, the bearing journals  15  continue to be held in the guideways  16 , so that they do not have to overcome either a step or a misalignment as the sunroof  13  is slid open. Since the middle section  5  and the roof part  7  swivel towards each other on the joint  12 , during this swiveling, the panel  13  can be held motionless parallel to the rear window  6 , which is part of the middle section  5 , and yet remain with the arms  14  in the guideways  16  of the front roof part  7 . 
   During the swiveling open of the roof parts  3  and  7 , the middle section  5  passes through the extension plane of the main posts  4  due to the height shift of the planes of the joints  9  and  10 , on the one hand, and  11  and  12 , on the other hand. The long sides of the articulated parallelogram, formed by the main posts  4  and the middle section  5 , completely fold towards each other, so that at the end, the parallelogram orientation has changed. In this way, the middle section  5  arrives in a lowered position in the automobile body  20  above the main posts  4  ( FIG. 7 ). This is very advantageous, because it results in additional storage space under the middle section  5  with the rear window  6 . 
   With the option of a horizontal displacement of the whole roof  2 , the roof  2  would first be moved towards the rear ( FIG. 13 ) before the movement to swivel it open is initiated and can then be moved back towards the front after the roof has been completely opened. 
   The complete folding of the parallelogram is brought out again in the schematic overview in  FIGS. 9 to 12 . The essentially rod-shaped parts shown in this series of drawings were provided with the reference numbers  4 ,  5  and  7  for the corresponding overall parts for the purpose of simplification, since, where the sequence of movements is concerned, it does not matter how any of the supporting frame parts for the specified units  4 ,  5 ,  7  are designed. The sunroof  13  also plays no role in the basic sequence of movements illustrated here. As the drawings show, additional links beyond parts  4  and  5  are not necessary. The parallelogram is closed by the roof part  7  that connects the pivot joints  10  and  12  without there being any need for a separate part here. The head clearance thus remains unrestricted. With the complete swiveling of the parallelogram, one achieves, on the one hand, a sealed contact between the middle section  5  and the main posts  4  with the roof  2  closed and, on the other hand, mounting of the middle section  5  in an elevated plane to increase the trunk space. 
   The invention can be used both in vehicles with manually moved roofs and in vehicles with fully automatically or semiautomatically moved roofs  2 . It is also possible to provide drives only for the horizontal movement H and to carry out the actual folding or unfolding of the roof  2  manually.