Abstract:
A convertible roof including a mechanism to actively control a second roof bow. In another aspect, a unique and novel way to control the folding of the convertible roof mechanism is employed such that a portion of the convertible roof serves as a cover that conceals the convertible roof within the boot well. In another aspect, the convertible roof is a “Z” folding top having four pairs of roof rails is also disclosed.

Description:
BACKGROUND AND SUMMARY OF THE INVENTION 
     This invention generally relates to convertible roofs for automotive vehicles and, more particularly, to a convertible roof that is stored in a stowage compartment of the vehicle with an exterior portion of the roof facing upward and covering the compartment. 
     Traditional soft-top convertible roofs for automotive vehicles typically employ three, four or five roof bows, having an inverted U-shape spanning transversely across the vehicle for supporting a vinyl, canvas or polyester fabric pliable roof cover. A number one roof bow is mounted to a pair of front roof rails and is typically latched to a stationary front header panel of the automotive vehicle body disposed above the front windshield. A number two roof bow is typically mounted to a pair of center roof rails which are pivotably connected to the front roof rails. Furthermore, the number three, four and any additional optional roof bows are commonly mounted to a pair of rear roof rails which are pivotably coupled to the center roof rails. The roof cover can also have a hard or rigid portion along with the pliable portion. For example, reference should be made to U.S. Pat. No. 5,429,409 entitled “Convertible Top”, which is incorporated by reference herein. Most traditional convertible roofs are stowed in a boot well or stowage compartment that is located aft of a passenger compartment in the vehicle. A boot or tonneau cover is then used to cover the boot well and conceal the convertible roof from view and/or protect the stowed roof from the environment. 
     The use of a boot cover or tonneau cover increases the cost and complexity of a vehicle with a convertible roof. Additionally, the separate boot cover also increases the number of operating parts and material required to conceal the stowed convertible roof from view and/or protect it from the environment. Therefore, it would be desirable if the boot cover could be integrated into the convertible roof such that a portion of the convertible roof also functions as the boot cover when the convertible roof is in its stowed position. 
     Traditional soft-top convertible roofs can present a packaging (stowing) difficulty when it is desired to use a “Z” folding roof. The difficulty is more pronounced when a “Z” folding roof is desired to be used on a larger vehicle (vehicle having front and rear seating areas). Traditional “Z” folding roofs have second and subsequent roof bows that are passively controlled and rely upon the movement of the flexible cover to position the roof bows when the convertible roof is transitioned from raised and stowed positions and typically have three pairs of coupled roof rails. Passively controlling the second roof bow, however, may not position the second roof bow in a proper orientation or may require excessive stowage space. Additionally, the use of three pairs of coupled roof rails also adds to the packaging difficulty. Therefore, it would be desirable to actively control the second and/or subsequent roof bows to control the positioning of the roof bows when transitioning from raised and stowed positions. It would also be desirable to provide a “Z” folding roof that utilizes a fourth pair of roof rails. 
     In accordance with the present invention, a convertible roof is provided which includes a mechanism to actively control a second roof bow. In another aspect of the present invention, a unique and novel way to control the folding of the convertible roof mechanism is employed such that a portion of the convertible roof serves as a cover that conceals the convertible roof within the boot well. 
     Along with actively controlling a second roof bow and controlling the top so that a portion serves as a cover, additional objects, advantages and features of the present invention will become apparent from the following description and appended claims, taken in conjunction with the accompanying drawings. It should be understood that the detailed description and specific examples, while indicating the preferred embodiment of the invention, are intended for purposes of illustration only and are not intended to limit the scope of the invention. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The present invention will become more fully understood from the detailed description and the accompanying drawings, wherein: 
     FIG. 1A is a perspective view of a vehicle with a convertible roof in A raised operative position in accordance with the principles of the present invention; 
     FIG. 1B is a side elevation view of the vehicle of FIG. 1A with the convertible roof in a stowed position in accordance with the principles of the present invention; 
     FIG. 1C is an overhead view of the vehicle in FIG. 1B; 
     FIG. 2A is a side elevational view showing the right half of the preferred embodiment of the convertible roof folding mechanism of the present invention with the folding mechanism in a raised operative position; 
     FIG. 2B is a side elevational view showing the right side of the preferred embodiment of the convertible roof folding mechanism of the present invention with the folding mechanism in a midpoint between the fully raised and stowed positions; 
     FIG. 2C is a side elevational view showing the right side of the preferred embodiment of the convertible roof folding mechanism of the present invention with the roof folding mechanism in the stowed position; 
     FIG. 3A is a perspective view of a front portion of the folding mechanism of FIG. 2B showing a hinge assembly coupling the front and front center roof rails and a control assembly that controls the second roof bow; 
     FIG. 3B is a perspective view, taken opposite FIG. 3A, showing the hinge assembly coupling the front and front center roof rails and the control assembly that controls the second roof bow; 
     FIG. 4A is a perspective view of a midportion of the folding mechanism of FIG. 2B showing a hinge assembly coupling the front center roof rail with the rear center roof rail; and 
     FIG. 4B is a perspective view, taken opposite FIG. 3A, showing the hinge assembly coupling the front center roof rail with the rear center roof rail. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     The following description of the preferred embodiment is merely exemplary in nature and is in no way intended to limit the invention, its application, or uses. 
     FIGS. 1A-C show the preferred embodiment of a convertible roof  20  of the present invention. In this embodiment, convertible roof  20  is employed on an automotive vehicle  22  having a passenger compartment  24  with passenger seats  25  and a generally U-shaped boot well or stowage compartment  26 . Stowage compartment  26  is positioned aft of passenger compartment  24  with quarter trim portions  27  extending along a portion of sides of passenger compartment  24 . Convertible roof  20  is of the type utilizing a folding or top stack mechanism  28  that partially supports a roof cover  30  and is operable between a fully raised position, as shown in FIG. 1A, and a fully stowed position, as shown in FIGS. 1B and 1C. Roof cover  30  includes a hard or rigid portion  32 , a pliable or soft portion  34 , and a window or backlite  36 . Soft portion  34  is made from a pliable material, such as vinyl, canvas or a polyester fabric. If desired, hard portion  32  can be covered by the same material that comprises soft portion  34  to give a uniform appearance. Backlite  36  is attached to roof cover  30  and is not pivotably coupled to folding mechanism  28 . For example, reference should be made to U.S. Pat. No. 5,887,936 titled Backlite System For Use In An Automotive Vehicle Convertible Roof, by Cowsert, and U.S. Pat. No. 6,102,467 titled Backlite Retention System For Use In An Automotive Vehicle Convertible Roof, by Laurain et al., both of which are herein incorporated by reference. Backlite  36  can be made of either a rigid material, such as glass, as shown, or a pliable transparent vinyl material (not shown). 
     Referring to FIGS. 2A-C,  3 A-B, and  4 A-B, convertible roof  20  and folding mechanism  28  are shown symmetrical about a longitudinal, fore-and-aft center line (not shown) of vehicle  22 . Folding mechanism  28  includes right and left roof linkages on the respective right and left sides of vehicle  22 . For brevity, only the right side of folding mechanism  28  is shown and discussed, however, it should be understood that left side linkages are also provided as part of folding mechanism  28  and are mirrored images of the right side. Also, when using the terms “fore” and “aft” and “front” and “back” in describing components of folding mechanism  28 , such reference refers to the orientation of the components when folding mechanism  28  is in the fully raised position. 
     Folding mechanism  28  includes first roof bow  38  that extends transversely across vehicle  22  and has a front edge  39  that is latched to a stationary front header panel of vehicle  22  disposed above the front windshield when in the fully raised position, as shown in FIG.  1 A. First roof bow  38  controls the soft portion  34  of cover  30 . First roof bow  38  is fixedly connected to a front roof rail  40  Alternatively, first roof bow  38  can be formed integrally with front roof rail  40 ; for example, first bow  38  and front roof rail  40  can be integrally cast from aluminum or a magnesium alloy. Front roof rail  40  is pivotably coupled to a front center roof rail  42  by a first multi-link hinge assembly (MHA)  44 . First MHA  44  controls the rotation of front roof rail  40  relative to front center roof rail  42 . 
     Referring now to FIGS. 3A and 3B, the details of first MHA  44  are shown. First MHA  44  includes a pivot connection  46  between a back end portion of front roof rail  40  and an integral extension  47  of a front end portion of front center roof rail  42 . One end of a first link  48  is pivotably connected to the back end portion of front roof rail  40  at pivot  50  while an opposite end is pivotably connected to an end of a second link  52  at pivot  54 . An opposite end of second link  52  is pivotably connected to the front end portion of front center roof rail  42  at pivot  56 . Thus, first MHA  44  is a four-bar linkage that includes front roof rail  40 , first link  48 , second link  52 , and front center roof rail  42 . Movement of first MHA  44  is controlled by a first control link  58  which is pivotably coupled to first MHA  44 . As can be seen in FIG. 3A, a front end portion of first control link  58  is pivotably connected to first and second links  48  and  52  at pivot  54 . 
     Front center roof rail  42  is pivotably coupled to a rear center roof rail  60  by a second multi-link hinge assembly (MHA)  62 . As can best be seen in FIGS. 4A and 4B, second MHA  62  includes a pivot connection  63  between an integral extension  64  of a back end portion of front center roof rail  42  and an integral extension  65  of a front end portion of rear center roof rail  60 . One end of a third link  66  is pivotably connected to front center roof rail  42  at pivot  68  while an opposite end of third link  66  is pivotably connected to an end of a fourth link  70  at pivot  72 . An opposite end of fourth link  70  is pivotably connected to the front end portion of rear center roof rail  60  at pivot  74 . Thus, second MHA  62  is a four-bar linkage that includes rear center roof rail  60 , front center roof rail  42 , third link  66 , and fourth link  70 . Second MHA  62  controls the rotation of front center roof rail  42  relative to rear center roof rail  60 . 
     Second MHA  62  also controls the operation of first MHA  44  via first control link  58 . As was stated above, the front end portion of first control link  58  is pivotably connected to first MHA  44  at pivot  54 . A back end portion of first control link  58  is pivotably connected to second MHA  62  and, more specifically, to third link  66  at pivot  76 . When second MHA  62  moves, first control link  58  moves which in turn causes first MHA  44  to also move. Thus, not only does the movement of second MHA  62  control the rotation of front center roof rail  42  relative to rear center roof rail  60 , it also controls the movement of first MHA  44 , via first control link  58 , which in turn controls the rotation of front roof rail  40  relative to front center roof rail  42 . 
     First control link  58  also controls the movement of a second roof bow  78 . As can best be seen in FIGS. 3A and 3B, second roof bow  78  is pivotably coupled to front center roof rail  42  by control assembly  80 . Control assembly  80  includes second roof bow  78  which is pivotably connected to front center roof rail  42  at pivot  82 . One end of a bow control link  84  is pivotably connected to second roof bow  78  at pivot  86  while an opposite end of bow control link  84  is pivotably connected to first control link  58  at pivot  88 . Thus, control assembly  80  is a five-bar linkage that includes front center roof rail  42 , second roof bow  78 , bow control link  84 , first control link  58 , and third link  66  of second MHA  62  or second link  52  of first MHA  44 . Movement of second roof bow  78  relative to front center roof rail  42  is caused by movement of first control link  58  which moves in response to movement of second MHA  62 . Thus, the movement of control assembly  80  and of second roof bow  78  are controlled by the movement of second MHA  62 . 
     As can be seen in FIGS. 2A-2C, a back end portion of rear center roof rail  60  is pivotably coupled to an intermediate portion of a rear roof rail  90  at pivot  92  while an intermediate portion of rear center roof rail  60  is pivotably coupled to a front end portion of balance link  94  at pivot  96 . A back end portion of balance link  94  is pivotably coupled to vehicle  22  at pivot  98 . A back end portion of rear roof rail  90  is also pivotably coupled to vehicle  22  at pivot  100  which is behind and below pivot  98 . Movement of rear roof rail  90  relative to vehicle  22  is controlled by an automatically powered driving element or actuator (not shown) such as an electric motor or hydraulic piston. Alternatively, the top stack mechanism can be manually driven. A back end portion of a second control link  102  is pivotably connected to a front end portion of rear roof rail  90  at pivot  104 . A third roof bow  106  is also pivotably connected to second control link  102  and rear roof rail  90  at pivot  104 . Third roof bow  106  is not actively controlled. Rather, third roof bow  106  is attached to roof cover  30  so that movement of roof cover  30  causes third roof bow  106  to pivot relative to second control link  102  and rear roof rail  90 . A front end portion of second control link  102  is pivotably coupled to second MHA  62  and, more specifically, to third and fourth links  66  and  70  at pivot  72 . Second control link  102  controls the movement of second MHA  62 . Movement of second control link  102  is controlled by the movement of rear roof rail  90 . Thus, movement of rear roof rail  90  controls the movement of second MHA  62 . A fourth roof bow  108  is pivotably connected to rear roof rail  90  at pivot  110 . Fourth roof bow  108  is also connected to roof cover  30 . Fourth roof bow is not actively controlled. Rather, movement of fourth roof bow  108  is controlled by movement of roof cover  30 . 
     Referring now to FIG. 2A, folding mechanism  28  is shown in its fully raised position corresponding to roof cover  30  covering passenger compartment  24  of vehicle  22 . When in the raised position, front roof rail  40 , front center roof rail  42 , and rear center roof rail  60  are all generally aligned and first roof bow  38 , second roof bow  78 , third roof bow  106 , and fourth roof bow  108  are fully extended so that roof cover  30  is taught with backlite  36  fully deployed. When convertible roof  20  is to be retracted, first roof bow  38  is unlatched from the front header of vehicle  22 , as is known in the art, and the driving element (not shown) begins to cause rear roof rail  90  to rotate about pivot  100  in a clockwise direction when folding mechanism  28  is viewed from the perspective shown in FIGS. 2A-2C. 
     As can be seen in FIG. 2B, as folding mechanism  28  moves from the raised position toward the stowed position, the clockwise rotation of rear roof rail  90  causes second control link  102  and rear center roof rail  60  to move to the right and rotate counter clockwise relative to rear roof rail  90  and balance link  94 . The movement of second control link  102  to the right causes second MHA  62  to rotate front center roof rail  42  clockwise relative to rear center roof rail  60 . Second MHA  62  also pushes first control link  58  toward first MHA  44  which in turn causes front roof rail  40  to rotate counter clockwise relative to front center roof rail  42 . The movement of first control link  58  also causes control assembly  80  to rotate second roof bow  78  in a counter clockwise direction relative to front center roof rail  42 . The movement of folding mechanism  28  causes roof cover  30  to relax and begin to fold along with folding mechanism  28 . The relaxing of roof cover  30  allows third and fourth roof bows  106  and  108  to rotate relative to folding mechanism  28  about respective pivots  104  and  110  as roof cover  30  folds. Backlite  36  also begins to fold into stowage compartment  26  as roof cover  30  folds. The active controlling of second roof bow  78  by control assembly  80  positions second roof bow  78  in a desired orientation and facilitates the stowage of top  20 . 
     Referring now to FIG. 2C, folding mechanism  28  is shown in its fully stowed position which corresponds to being located within stowage compartment  26 . As can be seen, folding mechanism  28  folds in an accordion-type fashion so that folding mechanism  28  folds and stacks upon itself and an exterior portion of roof cover  30  and, more specifically, hard portion  32  of roof cover  30  faces upward from stowage compartment  26  and has a substantially horizontal orientation. Hard portion  32  covers the portion of stowage compartment  26  that is aft of passenger seats  25  and becomes essentially the only visible part of convertible roof  20  behind passenger seats  25  that can be seen when convertible roof  20  is in the stowed position. Hard portion  32  is configured so that a peripheral edge of hard portion  32  matches a shape or contour of a back belt of stowage compartment  26  to conceal and protect a portion of soft portion  34  and folding mechanism  28  when convertible roof  20  is in the stowed position. The left and right roof linkages of folding mechanism  28  are in quarter trim portions  27  of stowage compartment  26  when convertible roof  20  is in the stowed position. In short, convertible roof  20  of the present invention provides a unique ability to function as a convertible roof in its raised operative position and to function as an aesthetically attractive and rigid boot or tonneau cover in its stowed position. 
     When convertible roof  20  is moved from its stowed position to its raised position, folding mechanism  28  operates in a reverse fashion. The driving element (not shown) will be operated to cause rear roof rail  90  to rotate about pivot  100  in a counter clockwise direction. The counter clockwise rotation of rear roof rail  90  causes second control link  102  and rear center roof rail  60  to move to the left and rotate clockwise relative to rear roof rail  90  and balance link  94 . The movement of second control link  102  to the left causes second MHA  62  to rotate front center roof rail  42  counter clockwise relative to rear center roof rail  60 . Second MHA  62  also pulls first control link  58  away from first MHA  44  which in turn causes front roof rail  40  to rotate clockwise relative to front center roof rail  42 . The movement of first control link  58  also causes control assembly  80  to rotate second roof bow  78  clockwise relative to front center roof rail  42 . The movement of folding mechanism  28  causes roof cover  30  to expand and begin to unfold along with folding mechanism  28 . The expanding of roof cover  30  causes third and fourth roof bows  106  and  108  to rotate relative to folding mechanism  28  about respective pivots  104  and  110  as roof cover  30  unfolds. Backlite  36  also begins to unfold from stowage compartment  26  as roof cover  30  unfolds. When folding mechanism  28  reaches its fully raised position, roof cover  30  is taught and front edge  39  of first roof bow  38  can be latched to the front header of vehicle  22  above the front windshield. The active controlling of second roof bow  78  by control assembly  80  positions second roof bow  78  in a desired orientation. 
     While various aspects of convertible roof  20  and folding mechanism  28  have been disclosed, it will be appreciated that many other variations may be employed without departing from the scope of the present invention. For example, MHAs  44 ,  62  may be more than four-bar linkages. Additionally, the attachment of first control link  58  to first MHA  44  can be at a location other than pivot  54 . For example, first control link  58  can be pivotably connected to only one of first or second links  48  and  52 . The exact location of the various pivots of folding mechanism  28  can vary from their locations as shown in the drawings and still be within the scope of the present invention. For example, pivot  46  that pivotably connects front roof rail  40  to front center roof rail  42  can be located further toward the front end of front roof rail  40 . Furthermore, the specific configurations and orientations of the various linkages and roof rails can have shapes that differ from those shown and still be within the scope of the present invention. Additionally, the roof can be stowed in a rear seating area of the passenger compartment. 
     The foregoing discussion discloses and describes merely an exemplary embodiment of the present invention. One skilled in the art will readily recognize from such discussion, and from the accompanying drawings and claims, that various changes, modifications and variations can be made therein without departing from the spirit and scope of the invention as defined in the following claims.