Abstract:
A method is provided for manufacturing an upper reveal that conforms to a curved portion of a window opening of a motor vehicle door frame. The upper reveal is formed from TPV and a carrier. The method includes the steps of: co-extruding the TPV with the carrier; curing the TPV to form the upper reveal; heating the upper reveal to a temperature greater than a heat deformation temperature of the TPV; and bending the upper reveal to conform to the curved portion of the window opening of the motor vehicle door frame.

Description:
FIELD OF THE INVENTION 
     The invention relates to an upper reveal for a window opening of a motor vehicle door frame. More particularly, the invention relates to a method of manufacturing an upper reveal that conforms to the curvature of a window opening of a motor vehicle door frame. 
     DESCRIPTION OF RELATED ART 
     A door of a motor vehicle typically includes a door frame defining a window opening. A retractable window pane and a fixed window pane are disposed within the window opening. An upper reveal is typically secured to a header portion of the door frame and extends along the window opening. The upper reveal provides sealing engagement between the header and a body portion of the motor vehicle when the door is closed. At the same time, an outside surface of the upper reveal is disposed along the exterior of the door of the motor vehicle. Therefore, the upper reveal must have an aesthetically pleasing appearance. 
     In many motor vehicle doors, particularly rear doors, the window opening of the door frame has a curved portion or corner to complement the overall styling of the motor vehicle. As a result, the upper reveal must be able to be bent to conform to such curved portions or corners. Upper reveals generally include an outer layer, which is typically a thermoset material such as PVC or EPDM rubber, extruded onto a rolled metal carrier. The upper reveal is then stretch bent in order to conform to the curved or corner portion of the window opening. Bending the upper reveal tends, however, to adversely affect the upper reveal. More specifically, bending often results in appearance flaws such as crimping, creasing, bulging, buckling, or the like. 
     Upper reveals made up of two discrete pieces for conforming to the curvature of the window opening have been utilized to avoid the aforementioned appearance flaws. These upper reveals include a generally planar, extruded portion and a stamped metal portion having molded edges. The extruded portion fits along a generally planar portion of the window opening while the stamped metal portion conforms to the curvature of the corner or curved portion of the window opening. This configuration results, however, in an unattractive, visible joint at the spot where the mismatched extruded and stamped portions meet, thereby detracting from the overall appearance of the motor vehicle. In addition, the need for expensive tooling required to manufacture the stamped metal portion of the upper reveal is not cost-effective. 
     Thus, there remains a need for a cost-effective upper reveal that conforms to a corner or curved portion of a window opening and provides the door frame with an aesthetically pleasing appearance. 
     SUMMARY OF THE INVENTION 
     According to one aspect of the invention, a method is provided for manufacturing an upper reveal that conforms to a curved portion of a window opening of a motor vehicle door frame. The upper reveal is formed from TPV and a carrier. The method includes the steps of: co-extruding the TPV with the carrier; curing the TPV to form the upper reveal; heating the upper reveal to a temperature greater than a heat deformation temperature of the TPV; and bending the upper reveal to conform to the curved portion of the window opening of the motor vehicle door frame. 
     According to another aspect of the invention, a method for manufacturing an upper reveal, having a decorative trim, for a window opening of a motor vehicle door frame from a TPV material and a carrier includes the steps of: co-extruding the TPV with the carrier; curing the TPV to form the upper reveal; heating the upper reveal to a temperature greater than a heat deformation temperature of the TPV; bending the upper reveal to conform to the curved portion of the window opening of the motor vehicle door frame; and applying the decorative trim to the upper reveal. 
     According to still another aspect of the invention, a method for manufacturing an upper reveal, having opposing ends covered by end caps, for a window opening of a motor vehicle door frame from TPV and a carrier includes the steps of: co-extruding the TPV with the carrier; curing the TPV to form the upper reveal; and molding the end caps to the opposing ends of the upper reveal. 
     According to yet another aspect of the invention, a method for manufacturing an upper reveal from TPV of different durometer values for conforming to a curved portion of a window opening of a motor vehicle door frame includes the steps of: co-extruding the TPV of different durometer values, curing the TPV to form the upper reveal, heating the upper reveal to a temperature greater than a heat deformations temperature of the TPV; and bending the upper reveal to conform to the curved portion of the window opening of the door frame. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Advantages of the present invention will be readily appreciated as the same becomes better understood by reference to the following detailed description when considered in connection with the accompanying drawings wherein: 
         FIG. 1  is a fragmentary, perspective view of a motor vehicle including an upper reveal extending along a window opening of a door frame; 
         FIG. 2  is a cut-away perspective view of the upper reveal including a molded strip and a carrier; 
         FIG. 3  is a cross-sectional view of the upper reveal; 
         FIG. 4  is a cross-sectional view of the upper reveal secured to a header flange of the door frame; 
         FIG. 5  is a cut-away, perspective view of the upper reveal including a decorative trim applied thereto; 
         FIG. 6  is a cut-away, perspective view of the upper reveal including the molded strip of TPV without the carrier; 
         FIG. 7  is a cut-away, perspective view of a bent upper reveal including end caps molded thereto; 
         FIG. 8  is a schematic of a method of manufacturing the upper reveal according to one embodiment of the invention; 
         FIG. 9  is a schematic of a method of manufacturing the upper reveal according to another embodiment of the invention including the step of applying a decorative trim; 
         FIG. 10  is a schematic of a method of manufacturing the upper reveal similar to  FIG. 9  wherein the step of applying the decorative trim is performed after the upper reveal has been bent; 
         FIG. 11  is a schematic of a method of manufacturing the upper reveal according to still another embodiment of the invention; and 
         FIG. 12  is a schematic of a method of manufacturing the upper reveal according to yet another embodiment of the invention. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Referring to  FIG. 1 , a door, generally indicated at  10 , for a motor vehicle  12  includes a door frame  14 . Although it will be appreciated that the door  10  may be any of numerous motor vehicle doors, in an exemplary embodiment the door  10  is a rear door. The door frame  14  of the rear door  10  includes a B-pillar portion  16 , a C-pillar portion  18 , and a belt line  20 . The belt line  20  extends longitudinally between the B-pillar portion  16  and the C-pillar portion  18 . 
     The door frame  14  defines a window opening  22 , the particular shape of which will vary depending upon vehicle styling considerations. A retractable window pane  24  selectively closes a portion of the window opening  22 , and a fixed window pane  26  closes a remaining portion of the window opening  22 . A division post  28  separates the retractable window pane  24  from the fixed window pane  26 . The window opening  22  includes a curved portion  30  adjacent the C-pillar portion  18 . The term “curved portion” is not intended to be narrowly construed. To this end, it is contemplated that the term “curved portion” encompasses any of numerous non-linear configurations, including a corner of the window opening  22 . 
     An upper reveal, generally shown at  32 , extends along the window opening  22  between the B-pillar portion  16  and the belt line  20  adjacent the C-pillar portion  18 . Part of the upper reveal  32  is bent to conform to the curved portion  30  of the window opening  22 . The upper reveal  32  is secured to a header flange  34 , shown in  FIG. 4 , which extends out from an upper portion or header  35  of the door frame  14 . Thus, the upper reveal  32  is disposed between the header  35  of the door frame  14  and each of the retractable  26  and fixed  28  window panes. 
     Referring to  FIGS. 2 and 3 , the upper reveal  32  includes a molded strip, generally indicated at  36 , and a carrier  38 . In the preferred embodiment, the molded strip  36  is formed as an extruded member from TPV (thermoplastic vulcanisate) of different durometer values to meet varying flexibility and durability requirements. Specifically, the TPV is co-extruded with the carrier  38  so as to completely embed the carrier  38  within the molded strip  36 . The upper reveal  32  is initially extruded as a generally linear piece, as shown in  FIG. 2 , which may be utilized for generally linear portions of the window opening  22 . 
     Referring to  FIG. 3 , the molded strip  36  includes a retention portion  40  having first  42  and second  44  segments, and a connecting segment  46  extending between the first  42  and second  44  segments. Preferably, the retention portion  40  has a durometer of approximately 40 Shore D. The first  42  and second  44  segments define an inner channel  48 . A plurality of retention members  50  extends out from at least one of the first  42  and second  44  segments into the inner channel  48 . The header flange  34 , which extends along the upper portion  35  of the door frame  14  adjacent the window opening  22  (as shown in  FIG. 4 ), is received within the inner channel  48 . The plurality of retention members  50  frictionally engages the header flange  34  within the inner channel  48  to mount the upper reveal  32  along the window opening  22  of the door frame  14 . 
     Referring again to  FIGS. 2 and 3 , the carrier  38  is generally U-shaped and is embedded within the retention portion  40  of the molded strip  36 . More specifically, the carrier  38  is embedded within the first segment  42 , the second segment  44 , and the connecting segment  46  to provide rigidity to the upper reveal  32 . The carrier  38  may initially have a fishbone or diamond configuration prior to conforming to the illustrated U-shape during extrusion. In the preferred embodiment, the carrier  38  is a roll formed metal, such as aluminum or steel. It is, however, contemplated that the carrier  38  could be molded from a thermoplastic material. The retention portion  40  may be formed with an air gap (not shown) adjacent the connecting segment  46  to prevent read-thru of metal as the TPV is co-extruded with the carrier  38 . 
     Referring to  FIGS. 3 and 4 , the upper reveal  32  also includes a pair of spaced apart closeout lips  54 ,  56  extending out from the first segment  42  for concealing a portion of the frame  58 . Each of the pair of spaced apart closeout lips  54 ,  56  has a durometer of approximately 75 Shore A. When the door  10  is closed, the pair of closeout lips  54 ,  56  sealingly engage the frame  58 , as shown in  FIG. 4 . 
     Still referring to  FIGS. 3 and 4 , the upper reveal  32  further includes an interior sealing lip  60  extending out from the first segment  42  of the retention portion  40 . The interior sealing lip  60  guides the header flange  34  into the inner channel  48  during attachment of the upper reveal  32  to the door frame  14 . The interior sealing lip  60  also sealingly engages the header  35 . 
     The retention portion  40  of the upper reveal  32  further includes spaced apart first  62  and second  64  legs extending out from the second segment  44 . The first  62  and second  64  legs define an outer channel  66  therebetween. Each of the first  62  and second  64  legs includes an end portion  68  extending into the outer channel  66 . Preferably, the first  62  and second  64  legs have a durometer of approximately 50 Shore D. A fastener  76 , shown in  FIG. 4 , extends through the second leg  64  and a portion of the header  35  adjacent the header flange  34  to mount the upper reveal  32  to the door frame  14 . It is appreciated that although only one fastener  76  is shown, a plurality of fasteners  76  is utilized to mount the upper reveal  32  along the entirety of the header flange  34 . 
     Referring to  FIG. 4 , a glass run insert  70  is disposed within the outer channel  66  for receiving the retractable  26  and fixed  28  window panes thereagainst. The glass run insert  70  includes edge portions  72 ,  74  that contact the window panes  26 ,  28  within the outer channel  66  and provide sealing engagement between the window panes  26 ,  28  and the upper reveal  32 . It is appreciated that although the glass run insert  70  has been disclosed as a discrete component that is snap fit into engagement with the upper reveal  32 , the glass run insert  70  may, in the alternative, be integrally formed with the upper reveal  32 . 
     Referring back to  FIG. 3 , the upper reveal  32  includes a reveal or “A” surface  78  extending along the molded strip  36 . The reveal surface  78  is disposed along the exterior of the motor vehicle  12  when the upper reveal  32  is secured to the header flange  34 . A decorative trim  80 , shown in  FIG. 5 , may be applied along the reveal surface  78  to provide the upper reveal  32  with an aesthetically pleasing, finished exterior. More particularly, the decorative trim  80  has either a high gloss black finish, a low gloss black finish, a chrome finish, or is colored to match, complement, or contrast the appearance of the rest of the motor vehicle  12 . The decorative trim  80  is preferably formed from thermoplastic polyolefin (TPO). 
     Referring to  FIG. 6 , the upper reveal  32  may be formed exclusively from TPV of different durometer values. Thus, in such an embodiment, the upper reveal  32  is formed without the carrier  38 . Forming the upper reveal  32  exclusively from TPV results in an upper reveal  32  this is completely recyclable. 
     Referring to  FIG. 7 , ends caps  82  may be molded to opposing ends  84 ,  86  of the upper reveal  32 , which has been bent to conform to the window opening (not shown). The end caps  82  effectively close out the ends  84 ,  86  of the upper reveal  32 , which hides the otherwise rough, cut appearance of the ends  84 ,  86  of the upper reveal  32 . The end caps  82  may be utilized with any of the variations of the upper reveal  32  described above. 
     In one method of manufacturing the upper reveal  32  according to the invention, as shown in  FIG. 9 , the carrier  38  is first run through an extrusion die  82 . The carrier  38  is either a roll formed metal or a molded thermoplastic component. The extrusion die  82  is also fed with TPV of different durometer values to co-extrude the molded strip  36  with the carrier  38  in order to form the generally linear upper reveal  32 . During this co-extrusion step, the carrier  38  is completely embedded within the molded strip  36  of TPV. The upper reveal  32  is then passed through a series of cooling baths  84  in order to cure the TPV. The cooling bath  84  includes at least one sizing guide member  86  for maintaining the cross-section of the upper reveal  32  as the TPV is cured. The upper reveal  32  is then cut to a predetermined length by a cutter  88 . Next, the upper reveal  32  is heated in an oven  90  to a temperature that is above a heat deformation temperature of the TPV. Preferably, the heat deformation temperature for TPV is a temperature between approximately 120° C. and 150° C. When the heat deformation temperature is reached, a bending press  92  is utilized for bending the upper reveal  32  to conform to the curved portion  30  of the window opening  22 . Finally, the upper reveal  32  is secured to the header flange  34  extending along the header  35  of the door frame  14 , as shown in  FIG. 4 . 
     In another method of manufacturing the upper reveal  32  according to the invention, shown in  FIGS. 9 and 10 , the carrier  38  is first run through the extrusion die  82 . The carrier  38  is either a roll formed metal or a molded thermoplastic component. The extrusion die  82  is also fed with TPV of different durometer values to co-extrude the molded strip  36  with the carrier  38  in order to form the generally linear upper reveal  32 . During this co-extrusion step, the carrier  38  is completely embedded within the molded strip  36  of TPV. The upper reveal  32  is then passed through a series of cooling baths  84  in order to cure the TPV. The series of cooling baths  84  include at least one sizing guide member  86  for maintaining the cross-section of the upper reveal  32  as the TPV is cured. As the TPV is being cured, the decorative trim  80  may be applied to the reveal surface  78  of the molded strip  36  by an applicator  94 , as shown in  FIG. 9 . The upper reveal  32  is then cut to a predetermined length by a cutter  88 . Next, the upper reveal  32  is heated in the oven  90  to a temperature that is above the heat deformation temperature of the TPV. Preferably, the heat deformation temperature for TPV is a temperature between approximately 120° C. and 150° C. When the heat deformation temperature is reached, the bending press  92  is utilized for bending the upper reveal  32  to conform to the curved portion  30  of the window opening  22 . At this time, if the decorative trim  80  has not already been applied to the reveal surface  78  of the molded strip  36 , the decorative trim  80  may now be applied to the reveal surface  78  by the applicator  94 , as shown in  FIG. 10 . Finally, the upper reveal  32  is secured to the header flange  34  extending along the header  35  of the door frame  14 , as shown in  FIG. 4 . 
     In still another method of manufacturing the upper reveal  32  according to the invention, shown in  FIG. 11 , the carrier  38  is first run through the extrusion die  82 . The carrier  38  is either a roll formed metal or a molded thermoplastic component. The extrusion die  82  is also fed with TPV of different durometer values to co-extrude the molded strip  36  with the carrier  38  in order to form the generally linear upper reveal  32 . During this co-extrusion step, the carrier  38  is completely embedded within the molded strip  36  of TPV. The upper reveal  32  is then passed through a series of cooling baths  84  in order to cure the TPV. The series of cooling baths  84  include at least one sizing guide member  86  for maintaining the cross-section of the upper reveal  32  as the TPV is cured. The upper reveal  32  is then cut to a predetermined length by a cutter  88 . Next, the upper reveal  32  is placed inside a mold  100 , where the ends caps  82  are molded to the opposing ends  84 ,  86  of the upper reveal  32 . If bending of the upper reveal  32  is desired in order to the conform the upper reveal  32  to the curved portion of the window opening, the upper reveal  32  is heated in the oven  90  to a temperature that is above the heat deformation temperature of the TPV. Preferably, the heat deformation temperature for TPV is a temperature between approximately 120° C. and 150° C. When the heat deformation temperature is reached, the bending press  92  is utilized for bending the upper reveal  32  to conform to the curved portion  30  of the window opening  22 . The decorative trim  80  may be applied to the upper reveal  32  either as the TPV is being cured or after the upper reveal  32  has been bent to conform to the curved portion  30  of the window opening  22 . Finally, the upper reveal  32  is secured to the header flange  34  extending along the header  35  of the door frame  14 . 
     In yet another method of manufacturing the upper reveal  32  according to the invention, as shown in  FIG. 12 , TPV of different durometer values is fed into the extrusion die  82  to form the molded strip  36 . The carrier  38  is not utilized in the current method. Thus, the upper reveal  32  includes the molded strip  36  of TPV of different durometer values. The upper reveal  32  is then passed through a series of cooling baths  84  in order to cure the TPV. The series of cooling baths  84  include at least one sizing guide member  86  for maintaining the cross-section of the upper reveal  32  as the TPV is cured. The upper reveal  32  is then cut to a predetermined length by a cutter  88 . Next, the upper reveal  32  is heated in the oven  90  to a temperature that is above the heat deformation temperature of the TPV. Preferably, the heat deformation temperature for TPV is a temperature between approximately 120° C. and 150° C. When the heat deformation temperature is reached, a bending press  92  is utilized for bending the upper reveal  32  to conform to the curved portion  30  of the window opening  22 . The decorative trim  80  may be applied to the upper reveal  32  either as the TPV is being cured or after the upper reveal  32  has been bent to conform to the curved portion  30  of the window opening  22 . Finally, the upper reveal  32  is secured to the header flange  34  extending along the header  35  of the door frame  14 . 
     The invention has been described in an illustrative manner. It is to be understood that the terminology, which has been used, is intended to be in the nature of words of description rather than of limitation. Many modifications and variations of the invention are possible in light of the above teachings. Therefore, within the scope of the appended claims, the invention may be practiced other than as specifically described.