Patent Publication Number: US-11021115-B2

Title: Roof ditch sealing assemblies for vehicles including pre-gelled roof ditch sealer strips and methods of sealing roof ditches

Description:
TECHNICAL FIELD 
     The present specification generally relates to vehicle roofs and, more specifically, to roof ditch sealing assemblies for vehicle roofs including pre-gelled sealer strips and methods of sealing roof ditches. 
     BACKGROUND 
     Many vehicles include vehicle roofs that are welded to side panels of the vehicles. In order to facilitate welding, the vehicle roofs may be provided with a roof ditch that runs lengthwise along the vehicle roofs, between the vehicle roofs and the side panels of the vehicles. After welding the roofs to the side panels, the roof ditches may be filled with a sealer and/or preformed molding. The sealer may be in a liquid form and may tend to run lengthwise along the roof ditches. Such running of the sealer may be particularly pronounced for curved roofs and create inconsistent end portions. For example, as sealers are poured into the roof ditches and then allowed to cure, the ambient environment can affect the cure of the sealer leading to an inconsistent length and formation of gaps between the sealer and adjacent moldings. Moldings, while being solid and having relatively unchanging lengths, tend to be relatively expensive, require preforming and then assembly to the roof ditches. Further, moldings may require fasteners that anchor to the vehicle roofs, which can provide an access point for water to enter an interior of the vehicle. 
     What is needed are roof ditch sealing assemblies that are formed using pre-gelled roof ditch sealer strips that are partially cured at a location away from the vehicle to a predetermined size and then assembled within the roof ditches and finally cured. 
     SUMMARY 
     In accordance with one embodiment, a method of filling a roof ditch of a vehicle roof assembly is provided. The method includes delivering a sealer material to a mold channel of a mold. The sealer material is heated within the mold channel at a pre-gel heating temperature forming a pre-gelled roof ditch sealer strip. The pre-gelled roof ditch sealer strip is removed from the mold. The pre-gelled roof ditch sealer strip is installed into the roof ditch of the vehicle roof assembly. 
     In another embodiment, a vehicle includes a roof assembly including a roof having an outer facing surface and a roof ditch that extends below the outer facing surface. The roof ditch extends in a vehicle longitudinal direction between a front windshield and a rear window. A pre-gelled roof ditch sealer strip extends along a front portion of the roof ditch and rearward in the vehicle longitudinal direction toward a rear portion of the roof ditch. 
     These and additional features provided by the embodiments described herein will be more fully understood in view of the following detailed description, in conjunction with the drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The embodiments set forth in the drawings are illustrative and exemplary in nature and not intended to limit the subject matter defined by the claims. The following description of the illustrative embodiments can be understood when read in conjunction with the following drawings, where like structure is indicated with like reference numerals and in which: 
         FIG. 1  depicts a front perspective view of a pickup truck, according to one or more embodiments shown and described herein; 
         FIG. 2  schematically depicts a top of the pickup truck of  FIG. 1  illustrating a roof assembly, according to one or more embodiments shown and described herein; 
         FIG. 3  illustrates a method of forming a pre-gelled roof ditch sealer strip, according to one or more embodiments shown and described herein; and 
         FIG. 4  illustrates a method of filling a roof ditch of a vehicle roof assembly using the pre-gelled roof ditch sealer strip of  FIG. 3 , according to one or more embodiments shown and described herein. 
     
    
    
     DETAILED DESCRIPTION 
     Pickup trucks according to the present specification include a passenger cabin and a truck bed located rearward of the passenger cabin. The cabins are formed by side panels and a roof assembly that is connected to the side panels at opposite sides of the roof assembly. The roof assembly includes a vehicle roof that is connected to one side panel along a roof ditch that extends lengthwise from a front of the vehicle roof to a rear to the vehicle roof. The vehicle roof is also connected to another side panel along another roof ditch that extends lengthwise from the front of the vehicle roof to the rear of the vehicle roof. 
     A cured roof ditch sealer strip extends along the roof ditch from the front of the vehicle roof toward the rear of the vehicle roof. The cured roof ditch sealer strip is formed from a pre-gelled roof ditch sealer strip that has been partially cured before application to the vehicle. The pre-gelled roof ditch sealer strip is initially formed remote from the vehicle into an elongate strip from a workable resin material that is then only partially cured for the material&#39;s gel time until the sealer material gels. The term “gel time” refers to the time it takes for a resin material to gel or become so highly viscous that it can no longer be considered workable. Gelation of the sealer material is where the chemical reaction during the curing process has proceeded sufficiently so that the sealer material has achieved a flexible and non-flowing 3-D structure. For example, the sealer material may be heated at between about 120° C. and about 160° C. for between about three minutes and about eight minutes, such as at about 140° C. for about five minutes until the sealer material reaches a surface temperature of between about 90° C. and about 110° C. While pre-gelling of the sealer material may be accomplished using heat, room temperature gelling may be used depending on the sealer material using, for example, moisture, light or a multi-component (e.g., resin and catalyst) system. The pre-gelled roof ditch sealer strip may then be delivered to the vehicle for installation within the roof ditch and then fully cured in situ, as will be described in greater detail below. 
     As used herein, the term “vehicle longitudinal direction” refers to the forward-rearward direction of the pickup truck (i.e., in the +/− vehicle Y direction depicted in  FIG. 1 ). The term “vehicle lateral direction” refers to the cross-pickup truck direction (i.e., in the +/− vehicle X direction depicted in  FIG. 1 ), and is transverse to the vehicle longitudinal direction. The term “vehicle vertical direction” refers to the upward-downward direction of the pickup truck (i.e., in the +/− vehicle Z-direction depicted in  FIG. 1 ). As used herein, “upper” and “above” are defined as the positive Z direction of the coordinate axis shown in the drawings. “Lower” and “below” are defined as the negative Z direction of the coordinate axis shown in the drawings. 
     The terms “outboard” or “outward” as used herein refers to the relative location of a component in a direction with respect to a pickup truck centerline. The term “inboard” or “inward” as used herein refers to the relative location of a component in a direction with respect to the pickup truck centerline. Because the pickup truck structures may be generally symmetrical about the pickup truck centerline, the direction to which use of terms “inboard,” “inward,” “outboard” and “outward” refer may be mirrored about the pickup truck centerline when evaluating components positioned along opposite sides of the pickup truck  10 . 
     Referring to  FIG. 1 , a pickup truck is generally illustrated at  10 . The pickup truck  10  includes a passenger cabin  12  and a truck bed  14 . The pickup truck  10  includes a vehicle body including a body framework  18  that includes a pair of side panels  20  and  22  with side roof rail structures  24  and  26  and front pillars  28 . The front pillars  28  are connected to the side roof rail structures  24  and  26  and extend downwardly therefrom in the vehicle vertical direction. The front pillars  28  are located toward a forward end of the vehicle  10 , generally between a front windshield  32  and front side windows  34 . 
     The vehicle  10  includes a vehicle roof assembly  40  including a vehicle roof  42  that extends in the vehicle lateral direction between the side roof rail structures  24  and  26  and in the vehicle longitudinal direction between the front windshield  32  and a rear window  38 . While only an outer vehicle panel is illustrated, the vehicle roof  42  may be formed of multiple panels, such as an inner vehicle panel that is connected to the outer vehicle panel. Further, the vehicle roof assembly  40  may include a headliner that can form an interior panel of the vehicle roof assembly  40  that can be viewed from within the cabin  12  of the vehicle  10 . The headliner can also cover at least portions of the remaining vehicle roof assembly  40  from view from within the cabin  12 . 
     Referring to  FIG. 2 , a diagrammatic top view of the pickup truck  10  is illustrated including the side panels  20  and  22  and the vehicle roof assembly  40 . The vehicle roof assembly  40  includes the vehicle roof  42  that is connected to one side panel  20  along a roof ditch  46  that extends lengthwise between the front windshield  32  of the vehicle roof  42  and the rear window  38  of the vehicle roof  42 . The vehicle roof  42  is also connected to another side panel  22  along another roof ditch  52  that extends lengthwise from the front  48  of the vehicle roof  42  to the rear  50  of the vehicle roof  42 . 
     A rear roof ditch molding  54  is located at least partially within the roof ditch  46  at a rear portion  56  of the roof ditch  46 . The rear roof ditch molding  54  is preformed and then installed into the roof ditch  46 . The rear roof ditch molding  54  has a rear portion  58  that extends along a rear wall  60  of the passenger cabin  12  and a roof portion  62  that extends along the vehicle roof  42 . A cured roof ditch sealer strip  64  extends along a front portion  66  of the roof ditch  46 . The cured roof ditch sealer strip  64  may be, for example, a PVC based body sealer with select additives for UV/Mold protection. A combination roof ditch sealer dam and molding clip  70  is located at least partially between the rear roof ditch molding  54  and the roof ditch sealer strip  64 . In particular, the combination roof ditch sealer dam and molding clip  70  includes a roof ditch sealer dam  72  located between a rear end  74  of the roof ditch sealer strip  64  and a front end  76  of the rear roof ditch molding  54 . The roof ditch sealer dam  72  can inhibit overlap between the roof ditch sealer strip  64  and rear roof ditch molding  54  and provides a stop surface against which the roof ditch sealer strip  64  can abut to reduce any gap formation between the rear roof ditch molding  54  and the roof ditch sealer strip  64  in a reliable fashion. 
     Referring to  FIGS. 3 and 4 , a sealer material  80  is poured or otherwise deposited within a mold channel  88  of mold  84  (e.g., formed of silicon) at step  100  of  FIG. 4 . The mold  84  may then be transferred to an oven at step  102  where the sealer material  80  is heated at a temperature of between about 120° C. and about 160° C., such as about 140° C. at step  104 . While heating is described herein, there may be other methods of gelling depending on the type of sealer material. The sealer material  80  may be heated at that temperature for between about three and about eight minutes, such as about five minutes until a surface temperature of the sealer material  80  reaches between about 90° C. and about 110° C. The sealer material  80  may then be allowed to cool (e.g., at room temperature) forming a pre-gelled roof ditch sealer strip  82  at step  108 . The pre-gelled roof ditch sealer strip  82  may then be cut to a desired length at step  110 , which may depend on the model of vehicle to which the roof ditch sealer strip  82  is being installed. 
     The pre-gelled roof ditch sealer strip  82  may then be delivered to the vehicle and placed within the roof ditch  46  ( FIG. 2 ) at step  114 . Because of the gelation of the pre-gelled roof ditch sealer strip  82 , the pre-gelled roof ditch sealer strip  82  maintains its shape as it is delivered and installed within the roof ditch  46 . In some embodiments, an adhesive coating may be applied to the pre-gelled roof ditch sealer strip  82  and/or to the roof ditch  46  prior to installation of the pre-gelled roof ditch sealer strip  82  into the roof ditch  46  at step  114 . The rear roof ditch molding  54  may then be installed adjacent the pre-gelled roof ditch sealer strip  82  at step  118 . At step  120 , the pre-gelled roof ditch sealer strip  82  may then be painted along with the rest of the vehicle  10  and then baked with the vehicle  10  at a cure temperature that is higher than the pre-gel heating temperature (e.g., greater than 120° C.) to fully cure the sealer material and form the cured roof ditch sealer strip  64  at step  122 . In some embodiments, the mold channel  88  may be formed smaller than a width dimension of the corresponding roof ditch  46 , as the pre-gelled roof ditch sealer strip  82  may expand between about 10 percent and about 20 percent while undergoing the final curing at the second, higher temperature. 
     The above-described roof ditch sealing assemblies are formed using pre-gelled roof ditch sealer strips that are partially cured (pre-gelled) at a location away from the vehicle at a first gelling temperature, then assembled within the roof ditches and finally cured at a higher curing temperature. The final curing may take place when the vehicle paint is finally baked at the elevated curing temperature, rather than as a separate step. The pre-gelled roof ditch sealers can hold their shape, which can make them useful for installing in vehicles with relatively steeply curved roofs, such as sedans and coupes. The pre-gelled roof ditch sealers combine the benefits of both a plastic molded strip, which are relatively easily installed compared to fluid sealers and PVC sealers that are paintable and prevent disengagement during windy or car wash conditions. 
     While particular embodiments have been illustrated and described herein, it should be understood that various other changes and modifications may be made without departing from the spirit and scope of the claimed subject matter. Moreover, although various aspects of the claimed subject matter have been described herein, such aspects need not be utilized in combination. It is therefore intended that the appended claims cover all such changes and modifications that are within the scope of the claimed subject matter.