Convertible vehicle topwell drainage arrangement
FIELD OF THE INVENTION 
     This invention relates generally to convertible type vehicles and, more particularly to an arrangement for draining water from a molded shell-like topwell, providing a storage shell adapted for storing a collapsible top of a convertible vehicle when the top is in its down position. 
     BACKGROUND OF THE INVENTION 
     In most current convertible automotive vehicles the folded collapsible top is stored in a topwell storage area provided behind the rear seat of the vehicle. In both the up and down positions of the convertible top, the topwell storage area is subject to water accumulation as it is impossible to completely seal a rear window to the surrounding fabric material of the top. Further, the stitching through the top fabric material is a potential source of water leakage. 
     An example of one prior art convertible vehicle drainage arrangement is shown in U.S. Pat. No. 3,143,373 issued Aug. 4, 1964 to Fordyce entitled Drain Tube Assembly. The Fordyce patent embodies a drain tube of one piece construction having a body portion with a flange at each end which is larger than the drain openings in the two members. One flange is attached to the surface of one member at its drain opening and the second flange is compressible through the second drain opening in the other member. The second flange, upon it being projected though the second drain opening, expands its free end dimension, thereby retaining the drain tube against withdrawal from the opening of the second member. 
     The U.S. Pat. No. 4,071,273 issued Jan. 31, 1978 to Hack et al. discloses a water discharge, especially for hollow spaces in motor vehicles structures. The Hack patent discloses a water discharge nozzle in which the water discharge opening of the nozzle is surrounded on its side facing the atmosphere by an apron whose interior width and whose height amounts to a multiple of the interior width of the water discharge opening. 
     The U.S. Pat. No. 4,176,877 issued Dec. 4, 1979 to Schultz et al. discloses a vehicle water discharge nozzle of the type shown in the Hack patent wherein several water outlet or discharge openings are arranged in the wall of a funnel-shaped area. 
     The U.S. Pat. No. 2,991,120 issued Jul. 4, 1961 to Barenyi discloses a sedan type motor vehicle with rimmed top and a downwardly extending drainage tubular line which discharges within a double-walled structure, for example within the wheel fenders of the vehicle body. 
     SUMMARY OF THE INVENTION 
     It is a feature of the present invention to provide an improved drainage arrangement for a convertible vehicle molded shell-like topwell enabling split-installation of a drainage sub-assembly and the topwell during a vehicle assembly line operation. 
     It is another feature of the present invention to provide an improved drainage arrangement for a convertible vehicle molded topwell as set forth above wherein the first installed sub-assembly comprises a discharge fitting, a flexible water drainage tube and a sealing grommet. The fitting has an outlet spout resiliently connected to one upstream end of the flexible tube while the sealing grommet provides a resilient retention between a body panel aperture and the downstream discharge end of the tube. An advantage of the split-installation of the present invention is that the three element sub-assembly is adapted to be exactly installed, in a ready, un-hindered manner in a convertible vehicle body production line operation prior to the location thereabove of the topwell storage shell. 
     Another advantage of the present invention is to provide a molded topwell and drainage sub-assembly, as set forth above, wherein the topwell is adapted to be fixedly installed in the vehicle in a predetermined location by a plurality of fasteners without the need to locate, sort and connect fittings, drainage tubes, grommets, etc. during installation of the topwell. 
     It is yet another feature of the invention to provide an improved drainage arrangement for convertible vehicle topwell wherein allow that a frusto-conical shaped drainage recess, integrally molded in a floor of the topwell, is adapted to be self-aligned, in a spaced manner, with a subjacent discharge fitting snap-fitted into an existing body panel aperture. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     These and other objects, features and advantages of the present invention will become apparent to those skilled in the art upon reference to the following written description and the accompanying drawings in which: 
     FIG. 1 is a fragmentary perspective view of a convertible vehicle body in its top down or storage position; 
     FIG. 2 is a fragmentary perspective view of the convertible vehicle body of the FIG. 1 showing portions of the topwell drainage arrangement; 
     FIG. 3 is a fragmentary enlarged detail perspective view of the topwell of FIG. 2; 
     FIG. 4 is a fragmentary top view taken on the line 4--4 of FIG. 3; 
     FIG. 4A is a fragmentary vertical sectional view, partly in elevation, taken on the line 4A--4A of FIG. 4; 
     FIG. 5 is an fragmentary enlarged perspective detail view of the right hand topwell section of FIG. 3; 
     FIG. 6 is an enlarged detail perspective view of the left hand top well section of FIG. 3; 
     FIG. 7 is a fragmentary vertical sectional view taken on the line 7--7 of FIG. 6; 
     FIG. 8 is a fragmentary perspective view of the left hand flexible water drainage tube; 
     FIG. 9 is an enlarged detail perspective view of the water discharge grommet of FIG. 7; 
     FIG. 9A is a plan view of the underside to the grommet-funnel of FIG. 9; 
     FIG. 10 is a fragmentary vertical sectional view taken on the line 10--10 of FIG. 8; 
     FIG. 11 is a fragmentary enlarged vertical sectional view taken on the line 11--11 of FIG. 2; and 
     FIG. 12 is a fragmentary enlarged vertical sectional view taken on the line 12--12 of FIG. 2. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Referring now to the drawings and more particularly to FIG. 1, a convertible automotive vehicle 10 includes a convertible top 11 shown placed in a top down or storage position in a topwell assembly 12. FIG. 2 shows the topwell assembly 12, assembled in convertible vehicle body 13 and supported in operational spaced relationship on a horizontal underlying body support panel 14 (FIG. 7). The vehicle 10 also includes a back or rear seat assembly 15 (FIG. 1) positioned in front of the topwell assembly 12. It will be noted that the topwell assembly 12 performs a three fold function, i.e. collecting and draining away any accumulated water from the vehicle 10, providing a storage area when the top is up and providing a silencing mechanism to reduce vehicle noise. 
     As illustrated in FIGS. 2 and 3, the topwell assembly 12, molded from a synthetic resin or plastic material such as polyurethane for example, comprises a transversely extending molded central shell portion 16 interconnecting right hand and left hand side shell portions 17 and 18, respectively. FIG. 12 shows the central shell portion 16 having a front wall 20, which is supported on a transverse inverted U-bar or &#34;beauty-bar&#34; 19, having a outer conforming plastic cover 19&#39; fitted thereon. 
     The topwell assembly, which includes an aft wall 21, joined by topwell floor 22, provides a surface area for storing both the convertible top 11, when the top is in the down position. Further, the topwell provides a storage space for luggage or other materials when the top 11 is in an up or cover position. 
     The topwell floor 22 is molded with a water collecting network, generally indicated at 23. In the disclosed embodiment the floor 22 includes a plurality of transversely extending longitudinally spaced channels 24 each terminating in arcuate mirror image portions 25 at their outboard ends. The arcuate end portions 25 each drain into associated right hand and left hand collecting areas 26. The channel network 23 provides a structural support to further increase the rigidity and strength of the topwell molded floor 22. 
     With reference to FIG. 7, the topwell assembly 10 further includes an insulating material 28 on the backside or underside surface 29 of the floor 22 and the collecting areas 26. The purpose of the insulating material 28 is to reduce vehicle noise through noise dampening and absorption. Preferably, the insulating material 28 includes a pad of fibrous or foam material adhered or bonded to the underside surface of the floor 22. 
     Additionally, the channel network 23 splits the water drainage into right hand and left hand outboard and forward flows toward their respective collecting areas 26. Each collecting area has a drain arrangement, generally indicated at 30 in FIG. 7, from which the water exits each side of the vehicle 12. 
     It will be appreciated that the topwell assembly 12, which may be molded as a unitary member, is made in a shape which conforms to an environment of continuous and non-continuous surfaces. As a formed part, the topwell assembly 12 allows for maximum use of storage space while minimizing any gaps and voids in adjacent parts. 
     Referring to FIG. 7, the drain arrangement 30 comprises a water run-off drainage recess 32 integrally molded in the shell depressed collecting floor portion 26. The recess 32 has a frusto-conical shaped side wall 34 having a male taper surface 35 defining an upper circular inlet opening 36 and a lower apertured base wall 38. It will be noted that the recess base wall 38 has a circular opening 39 with has its center aligned on vertical axis of symmetry &#34;A&#34; of the frusto-conical shaped recess 32. 
     With reference to FIGS. 7 and 9 a one-piece water discharge fitting, generally indicated at 40, is shown as an integral one-piece member formed of synthetic resin or plastic material. As seen in FIG. 4 the fitting 40 is supported in an existing lightening oval-shaped opening 41 formed in the vehicle horizontally disposed metal body panel 14. The body panel 14 is shown in FIG. 4 spaced a predetermined vertical dimension beneath the topwell floor water runoff drainage recess 32. 
     With reference to FIG. 9 the fitting 40 comprises an upper rectangular-shaped mounting collar 42 extending radially outwardly from an upper end circular opening 43. The fitting 40 is formed with a frusto-conical shaped funnel wall portion 44 defining a female taper internal surface 45 matching in predetermined spaced relation the exterior male taper surface 35 of drainage recess 32. The male and female tapered surfaces 35 and 45 respectively, are dimensioned to provide a frusto-conical shaped annular radially spaced clearance 46 therebetween. The radially spaced clearance 46 is substantially equal to the height of the horizontally disposed clearance space 47 between the mounting collar 42 and the overlying water collecting floor portion 26. 
     As best seen in FIGS. 4 the water discharge fitting 40 upper rectangle-shaped mounting collar 42 is defined by longitudinally spaced apart side edges 50 and laterally spaced apart end edges 52. The side edges 50 are shown positioned parallel to and spaced a predetermined overhang dimension &#34;X&#34; from oval-shaped body panel aperture linear side edge borders 51. It will be noted that the overhang of said side edges 50 establishes four collar corners juncture overlying areas thereby insuring adequate load transfer distribution between the collar and the subjacent support panel. The overhang dimension &#34;X&#34; is of the order of 5 mm in the disclosed embodiment. 
     FIG. 4 shows the fitting collar 42 having its end edges 52 being formed with oppositely facing downwardly projecting tabs 54 aligned on a vertically disposed transversely extending fitting plane of symmetry which plane includes a major axis centerline 55. 
     It will be noted in FIG. 7 that outer opposite faces of the tabs 54 define downwardly and outwardly sloped locking shoulders 56 while their distal free ends terminate in downwardly and outwardly bowed arcuate cam portions 58. It will be further noted in FIG. 9A that the tab cam portions 58 each have an leading arcuate profile 60 in plan formed by a radius of curvature &#34;R&#34; having its center on the fitting principal axis &#34;A&#34;. 
     As seen in FIG. 4 the cam profile radius of curvature &#34;R&#34; is substantially equal but slightly greater than to the radius of curvature &#34;R&#39;&#34; of the panel oval aperture half-round end edge borders 53. Thus, the tab compound-curved cam profile 60 allows the tabs 54 to readily self-center the fitting 40 above the oval-shaped aperture 41 for snap-action locking engagement of the tab shoulders 56. In FIG. 4A it will be seen that as the fitting collar side edges 50 overlie the body support panel 14 while the tab shoulders 56 engage the opposed arcuate edges of the support panel 14 thereby locking the fitting 40 in the oval aperture 41. It will also be noted that the fitting 40 is positively retained in the oval-shaped aperture 41 by virtue of its rectangular collar 42 providing four extended corner areas in overlying flush engagement with the upper surface of the body support panel 14. 
     As best seen in FIGS. 9 and 9A the collar undersurface includes fore and aft pairs of downwardly projecting snap-in prongs 59 spaced a predetermined dimension inwardly from each collar side edge 50. With reference to FIG. 4A it will be seen that each prong 59 has a retaining shoulder 59a adapted to engage an underside of the support panel 14 to insure positive retention of the fitting 40 in the aperture 41. 
     With reference to FIG. 7 the fitting frusto-conical shaped side wall 44 terminates in a lower small diameter bottom wall 62 having a vertically downwardly extending integral exit spout 63. The elongated spout 63 defines an axial passageway 64 between the recess outlet hole 39 and the fitting exit pipe concentric axial passageway. The fitting exit spout has its exterior surface 66 formed with a male taper, the lower exit end 67 of which is received in one end 68 of a length of flexible plastic tube 69. The tube upper end 68 is shown stretched over the lower downstream end of the exit pipe 63 for resilient retention thereon. 
     As seen in FIG. 8 the fitting 40 forms, together with the interconnecting tube 69 and a grommet washer 80, a sub-assembly 70 which is adapted for ready production line installation in the convertible body 13 prior to the installation of the topwell assembly 12. With reference to FIG. 8 it will be seen that with the fitting 40 snapped into the body inner panel oval-shaped aperture 41 the flexible tube 69 is feed downwardly on the forward side of body back panel 72 for rearward passage through a rectangular opening 74 therein. The tube 69 is then passed through an existing oval-shaped opening 76 in the body wheel well vertically disposed inner panel 78. With reference to FIG. 10 the tube 69 is retained in the opening 76 by a snap-in rubber sealing grommet 80. 
     It will be noted that the sealing grommet 80, the third element of the subassembly 70, has an oval-shaped radially extending flange 82 on inboard end of an oval-shaped connecting portion 84 sized for a snug fit in the panel opening 76. The tubular connecting portion 84 is formed with an outboard or exterior oval-shaped shoulder 86 spaced a predetermined axial dimension from the inboard flange 82. The connecting portion 84 is joined at its downstream or outboard end in an oval-shaped lead-in portion 88 having a its small oval end provided with a circular adapted to snugly surround the drainage tube 69. The sealing grommet 80 terminates in an outboard tubular portion 92 adapted to resiliently surround the inserted tube 69 preventing slippage of the tube during installation. 
     As seen in FIG. 10 the tube 69 has its open free discharge end 94 positioned in a body low pressure space such as the rear wheel-well area 96. The area 96 is defined intermediate the inner panel 78 and an outer body panel 98 such that drain water from the fitting spout 66 is discharged into an exterior low pressure area 96. 
     With reference to FIGS. 2 and 3 the topwell assembly 12 is shown positioned in the convertible body topwell area with its rear wall 21 being suitably secured to vehicle body upstanding backwall 72 (FIG. 11) as by headed fasteners 64. In the disclosed form the topwell fasteners 64 are of the conventional plastic-headed push-in type having a shank which includes a conical point and a series of flexible retention fins adapted to be received in a body sheet metal panel hole. Upon the topwell sub-assembly being secured to the vehicle body 13 the water collecting recess 32 is in axial alignment with the underlying fitting 40. 
     While the principles of the invention in connection with the specific apparatus has been described, it is to be understood that the foregoing detailed description has been made by way of example only and not as a limitation to the scope of the invention as set forth in the accompanying claims.