Abstract:
A vehicle roof having at least one cover element, which selectively closes or at least partially exposes a roof opening and which can be adjusted between a closed position and a lowered displacement position and, with respect to a vehicle longitudinal center plane, comprises a carrier element on either side, the carrier element comprising a guide path, which interacts with at least one guide element of a drive carriage for pivoting the cover element, the carriage being guided in a guide rail fixed to the roof. At least one rear-side control slide is disposed on the carrier element and guides the cover element in a guide channel of the respective guide rail during displacement of said element and secures the cover element against pivoting. When pivoting the cover element into the lowered displacement position, the rear-side control slide recedes into the respective guide channel of the respective guide rail while sliding over a ramp.

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The invention relates to a vehicle roof with at least one cover element which optionally closes or at least partially opens up a roof opening. 
     2. Related Technology 
     A vehicle roof of this type is known from practice and comprises a cover element which has a carrier element, which constitutes a pivoting or deployment arm for the cover element, along both of the lateral edges of said cover element with respect to a longitudinal center plane of the vehicle. Guide rails are arranged along the lateral edges of the roof opening, which can be closed by means of the cover element, said guide rails being arranged in a manner fixed to the roof and one of the carrier elements being guided displaceably in each thereof when the cover element is actuated. Furthermore, a driving carriage is arranged in each of the guide rails, the driving carriage, for the pivoting of the cover element, interacting with a guide track which is arranged on the respectively assigned carrier element of the cover element. The profile of the guide track defines a pivoting movement of the cover element as the driving carriages are moved in the guide rails, specifically in such a manner that the cover element can be pivoted between a closed position, in which the roof opening is completely closed, a ventilation position, in which a rear edge of the cover element is deployed in relation to a rear, fixed roof section, and a lowered displacement position, in which the cover element can be moved in the longitudinal direction of the vehicle under the rear, fixed roof section in order to open up the roof opening. During the pivoting operation, the cover element is secured against movement in the longitudinal direction of the vehicle by means of “control slides”. The control slides are arranged on the carrier elements of the cover element and interact with corresponding recesses on an upper boundary wall of the respective guide rail. When the cover element pivots into the lowered displacement position, the control slides enter a guide channel of the respective guide rail. 
     The problem with the above-described vehicle roof is that the cover element experiences a sudden offset when pivoting between the closed position and the lowered displacement position. The reason for this is that the carrier elements of the cover element each collide at the vehicle front end of the guide rails with a fixed stop which initiates a switch from the displacement movement into a pivoting movement such that the carrier elements of the cover element are moved upward by the steep rear profile of the carrier element guide tracks which interact with the driving carriages. The control slides, which are guided in the guide rails during the displacement, enter here into corresponding control recesses on the guide rails and thereby secure the cover element from moving in the longitudinal direction of the vehicle. During the lowering movement, the cover element drops rapidly downward along the steep rear profile of the carrier element guide tracks, which interact with the driving carriages, the control slides entering freely into the respective guide track of the relevant guide rail until they strike against a lower guide surface of same. 
     Furthermore, it is known from practice to control a sliding roof cover element with respect to the pivoting movement thereof by an additional control lever which interacts with a corresponding control element in the relevant guide rail. However, this solution is associated with a multiplicity of components and therefore also with high costs. 
     SUMMARY OF THE INVENTION 
     The invention provides a vehicle roof of the generic type mentioned at the beginning which is distinguished by a harmonious lowering movement of the cover element and a simultaneously low number of parts for the kinematics of a cover element. 
     Accordingly, the invention provides a vehicle roof with at least one cover element that optionally closes or at least partially opens up a roof opening, is displaceable between a closed position and a lowered displacement position and has a respective carrier element on both sides with respect to a longitudinal center plane of the vehicle, the carrier element comprising a guide track which, for the pivoting of the cover element, interacts with at least one guide element of a driving carriage that is guided in a guide rail that is fixed to the roof, wherein at least one rear control slide is arranged on the carrier element, said control slide securing the cover element during the pivoting thereof against moving in the longitudinal direction of the vehicle and, during movement of the cover element, being guided in a guide channel of the respective guide rail and securing the cover element against pivoting, wherein, during pivoting of the cover element into the lowered displacement position, the rear control slide enters the relevant guide channel of the relevant guide rail via a ramp. 
     The core of the invention consequently consists in providing damping in the form of a ramp for the rear control slide, the damping slowing down the entry and exit speed of the control slide into and out of the guide channel of the relevant guide rail in the vertical direction of the vehicle. A harmonious movement sequence when lowering the cover element into the displacement position thereof and when pivoting said cover element back into the closed position thereof can therefore be achieved with a low outlay on components. When the cover element is moved from the position thereof which opens up the roof opening into the closed position, the ramp serves as a stop for the cover element, with which stop the relevant control slide collides such that, by means of the interaction of the driving carriage and the guide track of the carrier element, the cover element can be pivoted upward out of the displacement position thereof into the closed position thereof. A further cover element stop possibly arranged in the front end region of the guide rails is therefore unnecessary. It is therefore also unnecessary to precisely coordinate a front stop and a control slide counterbearing which is formed on the guide rail and which, by interaction with the control slide, prevents displacement of the cover element during the pivoting movement thereof. 
     In an embodiment of the vehicle roof according to the invention that can be realized particularly cost-effectively, the ramps for the rear control slides are each formed by a notch in the respective guide rail. Additional components forming the ramps are therefore not required. As an alternative, the ramp may also be formed by an insert in the respective guide rail, which insert is formed, for example, as an injection molded plastic part. 
     A particularly harmonious movement sequence during the pivoting of the cover element can be achieved if the ramps each have a curved profile in the vertical direction of the vehicle. 
     In order to ensure precise entry of the rear control slides into an upper locking recess of the respective guide rail, the locking recess forming the counterbearing, a vehicle front edge of the ramps is in each case aligned at least approximately with a front edge of the upper locking recess of the respective guide rail. 
     An expedient embodiment of the vehicle roof according to the invention also comprises, in addition to the rear control slides, front control slides which are preferably likewise arranged on the carrier elements, each interact with a corresponding locking recess of the relevant guide rail and, during the movement of the cover element, are likewise each guided in a guide channel of the relevant guide rail. In order to be able to achieve the maximum possible movement distance of the cover element, an intermediate space, the dimensions of which in the vertical direction of the vehicle are larger than or equal to the dimensions of the front control slide in the vertical direction of the vehicle, is located between the vehicle front edge of the ramp and an upper wall of the respective guide rail. The front control slide can therefore be moved past the relevant ramp in the rear direction of the vehicle. 
     In order to ensure a harmonious transfer between the ramp and the locking recess for the rear control slide, in an expedient embodiment of the vehicle roof according to the invention, the rear control slide has an overall height which is greater than the intermediate space between the upper wall of the guide rail and the vehicle front edge of the ramp. 
     In particular, a ramp formed within the context of the invention for a rear control slide has proven advantageous if the rear end region of the guide track of the carrier element has a carry-along section which has a greater slope than that region of the relevant guide track which is arranged at the front of the end region. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Further advantages and advantageous refinements of the subject matter of the invention can be gathered from the description, the drawing and the patent claims. 
       An exemplary embodiment of a vehicle roof according to the invention is illustrated schematically in simplified form in the description and is explained in greater detail in the drawing below. In the drawings: 
         FIG. 1  shows a perspective top view of a vehicle roof according to the invention with a roof opening system; 
         FIG. 2  shows a schematic longitudinal section through the roof opening system in the region of the driving mechanism thereof along the line II-II in  FIG. 1  in the closed position of a cover element; 
         FIG. 3  shows a view corresponding to  FIG. 2  but in the ventilation position of the cover element; 
         FIG. 4  shows a view corresponding to  FIG. 2 , but in a lowered displacement position of the cover element; 
         FIG. 5  shows an enlarged view of a rear section of the cover element in conjunction with a guide rail with the cover element moved slightly rearward; 
         FIG. 6  shows a view corresponding to  FIG. 5 , but as a control slide moves onto a run-on ramp; 
         FIG. 7  likewise shows a view corresponding to  FIG. 5 , but as the control slide enters a locking recess; 
         FIG. 8  likewise shows a view corresponding substantially to  FIG. 5 , but shortly before the closed position of the cover element is reached; 
         FIG. 9  shows an enlarged view of a front section of the cover element in conjunction with the guide rail in the cover element position illustrated in  FIG. 8 ; 
         FIG. 10  likewise shows a view corresponding to  FIG. 5 , but after the closed position of the cover element has been reached; 
         FIG. 11  shows a view corresponding to  FIG. 9 , but in the closed position of the cover element; 
         FIG. 12  shows a view likewise corresponding to  FIG. 5 , but in the ventilation position of the cover element; and 
         FIG. 13  shows the front section of the cover element in the ventilation position. 
     
    
    
     DETAILED DESCRIPTION 
     The drawing illustrates a vehicle roof  10  of a passenger vehicle, which is provided with a roof opening  12  which can optionally be closed or at least partially opened up by means of a cover element  14 . The cover element  14  is part of a roof opening system, which is illustrated in detail in  FIGS. 2 to 13 , and comprises a glass body  16  which is provided with a frame  18  which is formed from polyurethane foam and in which an inner cover panel is embedded. The inner cover panel has fastening tabs  20  which protrude downward at right angles in relation to the plane of the glass body  16  and serve to connect the cover element  14  to cover element carriers  22  which are arranged on lateral edges of the cover element  14  on both sides of a longitudinal center plane of the vehicle and are part of a displacement device for the cover element  14 . The fastening tabs  20  are each screwed via a screw  24  to the respective cover element carrier  22 . 
     The displacement device for the cover element  14  serves to pivot the cover element  14  between a closed position, which is illustrated in  FIG. 2  and in which the roof opening  12  is closed, a ventilation position, which is illustrated in  FIG. 3  and in which a rear edge  26  of the cover element  14  is deployed upward in relation to a rear fixed roof section  28 , and a lowered displacement position, which is illustrated in  FIG. 4  and in which the cover element  14  can be moved along guide rails  30 A and  30 B, which extend along the lateral edges of the roof opening  12 , and under the rear fixed roof section  28 . 
     The description below ensues solely with reference to the displacement device region which is arranged on the left in the forward direction of travel and which is assigned to the guide rail  30 A. The displacement device region which is arranged on the right in the forward direction of travel and is assigned to the guide rail  30 B is formed in a manner corresponding thereto mirror-symmetrically with respect to the longitudinal center plane of the vehicle. 
     As can be gathered from the drawing, the displacement device comprises a driving carriage  32  which is guided displaceably in the longitudinal direction of the vehicle in the guide rail  30 A and is driven by means of a pressure-resistant driving cable (not illustrated specifically here). The driving carriage  30  comprises a guide pin  34 , which extends in the transverse direction of the vehicle and reaches through a guide track  36  which is designed as a slotted guide, is formed on the cover element carrier  22  and the profile of which in the longitudinal direction of the vehicle defines a pivoting operation of the cover element  14 , which pivoting operation is triggered by the driving carriage  32  moving in the longitudinal direction of the vehicle. In particular, the guide track  36  of the cover element carrier  22  has a region A which is assigned to the closed position (illustrated in  FIG. 2 ) of the cover element  14  and in which the guide pin  34  is located in said closed position. Furthermore, the guide track  36  has a front region B which is assigned to the ventilation position, illustrated in  FIG. 3 , and in which the guide pin  34  is arranged in said ventilation position. A rear guide track end region C is assigned to the lowered displacement position (illustrated in  FIG. 4 ) of the cover element  14 . In said lowered displacement position, the rear end region C serves as a carry-along section for the guide pin  34  of the driving carriage  32 . Said carry-along section constitutes an upwardly pointing bend in the guide track  34  and consequently has a greater slope than those regions of the guide track  34  which are arranged at the front of the end region C. 
     A slide  38  which is guided in a guide channel  40  of the guide rail  30 A and defines a pivot axis of the cover element  14  is arranged at the front end of the carrier element  22 . Furthermore, a front control slide  42  is arranged on the cover element carrier  22  to the rear of the slide  38 , said front control slide protruding in the transverse direction of the vehicle and, in a section in the longitudinal direction of the vehicle, having the basic shape of a parallelogram and securing the cover element  14  in the closed position illustrated in  FIG. 2  and in the ventilation position illustrated in  FIG. 3  against inadvertent displacement in the longitudinal direction of the vehicle. For this purpose, the front control slide  42  interacts via a front end surface  421  and a rear end surface  422  with a locking recess  44  on the upper wall  46  of the guide rail  30 A. The locking recess  44  is bounded at the front by a guide wall  441  and at the rear by a guide wall  442 . The guide walls  441  and  442  are each inclined in the direction of the vehicle rear such that, when the control slide  42  is moved in the locking recess  44 , which is designed in the manner of a slotted guide, the cover element  16  experiences an offset in the longitudinal direction of the vehicle, specifically when the cover element  14  pivots from the closed position into the ventilation position in the direction of the vehicle rear, and therefore the front edge of the cover element  14  is spaced apart from the front edge of the roof opening  12 , and a seal  47  which is arranged on the front edge of the cover element  14  cannot be squashed and damaged. 
     A rear control slide  48  is arranged in a rear region of the cover element carrier  22 , said rear control slide likewise protruding in the transverse direction of the vehicle and interacting with a rear locking recess  50  which is likewise formed on the upper wall  46  of the guide rail  30 A and is bounded by a front guide wall  501  and by a rear guide wall  502  which form inlet webs for the control slide  48  and guide the latter as it passes through the locking recess  50 . A ramp  52  is formed below the front edge of the locking recess  50 , the ramp constituting a notch in a lower boundary wall  54  of the guide rail  30 A and via which, when the cover element  14  is pivoted into the lowered displacement position, the control slide  48  enters a guide channel  56  of the guide rail  30 A in a sliding and damped manner. The ramp  52  has a curved profile in the vertical direction of the vehicle and a front edge  58  which is aligned at least approximately with the front guide wall  501  of the locking recess  50 . Furthermore, the front edge  58  of the ramp  52  forms, with the upper wall  46  of the guide rail  30 A, an intermediate space  60  which substantially corresponds to the dimensions of the front control slide  42  in the vertical direction of the vehicle such that said control slide can move past the ramp  52  when the cover element  16  is moved under the rear fixed roof section  28 . The overall height of the control slide  48  is larger than the intermediate space  60 , and therefore the control slide  48  can be harmoniously transferred from the ramp  52  into the locking recess  50  and vice versa. 
     In the embodiment described here, the guide track  36  is designed as a slotted guide mechanism of the cover element carrier  22 . As an alternative, it is, however, also conceivable for a web guide to be formed on a cover element carrier, said web guide being engaged around by a claw section of a driving carriage and forming the guide track which interacts with the guide element of the driving carriage. 
     The roof opening system illustrated in the drawing operates in the manner described below. 
     Starting from the closed position of the cover element  14 , which is illustrated in  FIG. 2  and in which the guide pin  34  of the driving carriage  32  is arranged in the region A of the slotted guide mechanism  36 , as the cover element  14  pivots into the ventilation position thereof, which is illustrated in  FIG. 3 , the driving carriage  32  is moved in the direction of the vehicle front into a region B of the slotted guide mechanism  36 , which region drops in the direction of the vehicle front in relation to the region A, and therefore, by interaction of the guide pin  34  with the slotted guide mechanism  36 , the rear edge  26  of the cover element  14  is deployed upward in relation to the fixed roof section  26 . At the same time, the control slide  42  is moved upward in the locking recess  44  such that, by means of the inclination of the guide walls  441  and  442 , the cover element  14  experiences a slight offset in the direction of the vehicle rear and, in order to protect the seal  47 , a gap is formed between the front edge of the cover element  14  and the front edge of the roof opening  12 . 
     If, in order to open up the roof opening  12 , the cover element  14  is to be moved under the rear fixed roof section  28 , the driving carriage  32 , likewise starting from the closed position illustrated in  FIG. 2 , is moved in the direction of the vehicle rear into the region C of the slotted guide mechanism  36 . As a result, the cover element  14  is pivoted about the pivot axis, which is defined by the slide  38 , into the lowered displacement position such that the control slide  48  enters through the locking recess  50  into the guide channel  56  of the guide rail  30 A. In this case, the control slide  48  moves onto the ramp or run-on ramp  52 , which is integrated in the guide rail  30 A, and therefore, even when the guide pin  34  enters the steeply positioned region C of the slotted guide  36 , the cover element carrier  22  does not drop freely into the guide channel  56  but rather experiences damping by the control slide  48  sliding on the curved ramp  52 . The pivoting operation into the lowered displacement position therefore develops harmoniously. The front control slide  42  is also then arranged in the guide channel  56  of the guide rail  30 A. The cover element  14  can now be moved to the rear and under the rear fixed roof section  28  by the driving carriage  32  moving in the direction of the vehicle rear, the smaller overall height of the front control slide  42  enabling it to move past the ramp  42  above the latter. 
     During closing of the roof opening  12 , the cover element  14  is moved in the direction of the vehicle front until the control slide  48  moves onto the ramp  52  which is formed integrally on the lower boundary wall  54  of the guide rail  30 A, which boundary wall forms the lower running surface for the control slide  48  (cf.  FIGS. 5 and 6 ). Said ramp therefore serves as a stop which controls the pivoting movement of the cover element  14  upward into the closed position thereof and permits “gentle” entry into the pivoting movement.  FIG. 7  illustrates the transfer of the control slide  48  from the ramp  52  to the locking recess  50  which is arranged in a manner favorable for tolerances. The pivoting operation itself is in turn triggered by the guide pin  34  of the driving carriage  32  moving in the slotted guide mechanism  36  in the direction of the vehicle front. In the closed position of the cover element  14 , the control slide  48  is arranged above and outside the locking recess  50 . When the control slide  48 , upon pivoting upward, moves out of the locking recess  50  and becomes inoperative, the locking of the cover element  14  is transferred in the longitudinal direction of the vehicle to the front control slide  42  which is then arranged within the front locking recess  44  (cf.  FIGS. 8 and 9 ). An inadvertent displacement of the cover element  14  is then prevented by the front control slide  42  which is arranged in the locking recess  44 . By means of the direct control with the ramp  52  forming the stop and with the transfer of the control slide  48 , which forms a control cam, from the lower running surface or boundary wall  54  of the guide rail  30 A to the upper region of the guide rail  30 A by means of the inlet webs  501  and  502 , the tolerances can be kept low. 
     LIST OF REFERENCE NUMBERS 
     
         
           10  Vehicle roof 
           12  Roof opening 
           14  Cover element 
           16  Glass body 
           18  Frame 
           20  Fastening tabs 
           22  Cover element carrier 
           24  Screw 
           26  Edge 
           28  Fixed roof section 
           30  A, B Guide rail 
           32  Driving carriage 
           34  Guide pin 
           36  Guide track 
           38  Slide 
           40  Guide channel 
           42  Front control slide 
           421  End surface 
           422  End surface 
           44  Locking recess 
           441  Guide wall 
           442  Guide wall 
           46  Upper wall 
           47  Seal 
           48  Rear control slide 
           50  Locking recess 
           501  Guide wall 
           502  Guide wall 
           52  Ramp 
           54  Boundary wall 
           56  Guide channel 
           58  Edge 
           60  Intermediate space