Abstract:
An improved division post is provided that eliminates the need for a metal carrier for support, eliminates the need for roll form tooling and stretch bend tooling which are expensive and time-consuming processes, and may be formed in a glass encapsulation mold and retain the curvature imparted by the mold. The improved division post may guide a window panel moveable along a first axis in a motor vehicle. The division post may comprise a body portion comprising a first material and having a generally U-shaped cross-section. The body portion may include a base and first and second opposing walls defining a channel. The channel may be configured to receive at least an edge of the window panel. The division post may further include a first sealing wing extending from the first wall into the channel and a second sealing wing extending from the second wall into the channel. The first and second sealing wings may comprise a second material that is different than the first material.

Description:
BACKGROUND OF INVENTION 
       [0001]    a. Field of the Invention 
         [0002]    The invention relates generally to a division post for guiding a moveable window panel in a motor vehicle, and in particular to an unsupported division post comprising a body portion free of structural metal and at least one sealing wing coextruded with the body portion, the unsupported division post configured for automotive glass encapsulation. 
         [0003]    b. Description of Related Art 
         [0004]    Most automotive doors have a body envelope created by two generally-parallel spaced apart inner and outer door panels forming a main body of the door. The top edges of the inner and outer door panels at the bottom of the window opening is often referred to as the belt line. A panel of window glass may be nested between the door panels. A window regulator is provided for selectively moving the glass panel in and out of the body envelope to open and close the window opening of the door. In many motor vehicles, the automotive door has a door frame above the belt line for enclosing the window opening and supporting the window panel in an uppermost position. Many motor vehicles provide both front and rear automotive doors. 
         [0005]    The front and rear side door window openings typically have one lateral boundary formed by a post. The posts of the front and rear door window openings are typically fixed to the doors and have longitudinal axes which are parallel with the axis of travel of the window panels. The posts of the front and rear door window openings are adjacent to the B-pillar of the vehicle. The B-pillar is the center body pillar that provides roof support. The tops of the posts are connected with or extend to header regions of the door window openings. The header regions provide an upper border for the window openings. The header region of the front door window frame transitions into a declining region that eventually intersects the belt line of the vehicle. This declining portion of the front window frame is adjacent to the A-pillar of the vehicle. The A-pillar is a front body pillar attached to the front windshield that supports the roof. 
         [0006]    The header region of the rear door window frame extends downward, eventually intersecting the belt line of the vehicle. This downward portion of the rear window frame is adjacent to the C-pillar of the vehicle. The C-pillar is a rear body pillar to which the back glass of the motor vehicle is attached that supports the roof. In a number of motor vehicles, the rear door assembly is designed with a forward window opening that carries a retractable window panel and a rearward opening that is equipped with a fixed window panel. The rear border of the window opening that carries a retractable window panel is provided by a division post that serves as a track for the moveable window&#39;s up and down travel. 
         [0007]    Conventionally, the front and rear door assembly may be assembled from discrete elements, including a window panel, the division post, glass run channel, and various configurations of moldings or trim pieces. As a result of being assembled from discrete elements, conventional designs may have a number of deficiencies, such as water leakage, wind noise, and problems with fit and finish. Molding processes have been used in which a portion of the trim surrounding the fixed window panel is fabricated by encapsulating the window periphery with a polymer using injection molding techniques. However, the attachment of a discrete glass run channel strip may leave the potential for water leakage and wind noise at the connection areas. 
         [0008]    A glass encapsulation molding process may be used to provide an encapsulated fixed window panel, where the trim surrounding the fixed glass, the division post, and the glass run channel, all molded as an assembly, form continuous seals around the corner of the moveable glass. 
         [0009]    Conventional division posts generally comprise rigid coextrusions made of a flexible elastomeric material extruded around a rigid metal formed carrier. Conventional division posts have a number of deficiencies. First, the metal may be relatively expensive. Second, conventional division posts require both rollform tooling to shape the metal carrier before and after extrusion and stretch bend tooling to match the curvature of both the moveable and fixed glass panels after extrusion. This tooling may be expensive and complicated. 
         [0010]    Accordingly, there remains a need for a division post that minimizes and/or eliminates these deficiencies in the prior art. 
       SUMMARY OF THE INVENTION 
       [0011]    The present invention provides a division post for guiding a window panel moveable along a first axis in a motor vehicle. The division post may comprise a body portion comprising a first material and having a generally U-shaped cross-section. The body portion may include a base and first and second opposing walls defining a channel. The channel may be configured to receive at least an edge of the window panel. The division post may further include a first sealing wing extending from the first (e.g., outboard) wall into the channel and a second sealing wing extending from the second (e.g., inboard) wall into the channel. The first and second sealing wings may comprise a second material that is different than the first material. 
         [0012]    A division post in accordance with the present invention is advantageous as compared to existing division posts. First, the inventive division post eliminates the need for a metal carrier for support and replaces it with a low-cost coextruded material. The coextruded material may have sufficient rigidity to guide and stabilize the window panel. Second, the inventive division post eliminates the need for roll form tooling and stretch bend tooling, which are expensive and time-consuming processes that require appropriate tooling. Third, although the inventive division post has sufficient rigidity to guide and stabilize the window panel, it may not be so rigid that it is not configured for use in the glass encapsulation mold. Rather, the inventive division post may follow the curvature of the mold during loading so that when the glass encapsulation molding operation is completed, the division post may retain the curvature imparted by the mold and may be secured to the fixed glass. 
         [0013]    Additional features, advantages, and embodiments of the invention may be set forth or apparent from consideration of the following detailed description, drawings, and claims. Moreover, it is to be understood that both the foregoing summary of the invention and the following detailed description are exemplary and intended to provide further explanation without limiting the scope of the invention as claimed. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0014]    The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate exemplary embodiments of the invention and together with the detailed description serve to explain the principles of the invention. In the drawings: 
           [0015]      FIG. 1  is a fragmentary, perspective view of a rear door assembly installed in a motor vehicle. 
           [0016]      FIG. 2  is a side, elevational view of a portion of a rear door assembly including a division post in accordance with the present invention. 
           [0017]      FIG. 3  is a cross-sectional view along line  3 - 3  of  FIG. 2 . 
           [0018]      FIG. 4  is a fragmentary, plan view of the open mold used with the division post in accordance with the present invention. 
           [0019]      FIG. 5  is a fragmentary, side elevational view of a portion of a rear door assembly including a division post in accordance with the present invention, illustrating the integration of the header trim strip, the fixed window panel, and the division post with the injected encapsulation portion of the trim being shown in phantom. 
           [0020]      FIG. 6  is a side elevational view of a portion of a rear door assembly including a division post in accordance with the present invention. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
       [0021]    Referring now to the drawings wherein like reference numerals designate corresponding parts throughout the several views,  FIG. 1  illustrates a rear door assembly  10  in motor vehicle  12 . In  FIG. 2 , a portion of rear door assembly  10  is shown isolated from motor vehicle  12 . Rear door assembly  10  includes a moveable window panel  14 , a division post  16 , fixed window panel  18 , and integrated trim  20 . 
         [0022]    Although a number of materials may be suitable for window panels  14 ,  18 , in most applications window panels  14 ,  18  may comprise conventional clear or tinted automotive glass panels. In other embodiments, window panels  14 ,  18  may comprise plastic, such as polycarbonate or other glazing type material. 
         [0023]    Division post  16  is provided for defining a channel for receiving, supporting, and guiding moveable window panel  14  during its up and down motion in the channel. In particular, division post  16  is provided for guiding a window panel moveable along a first axis  21 . As best illustrated in  FIG. 3 , division post may include a body portion  22  and first and second sealing wings  24 ,  26 . 
         [0024]    Body portion  22  is provided for structural rigidity and support in order to guide moveable window panel  14 . Body portion  22  may comprise a polymer. In an exemplary embodiment, body portion  22  may comprise polypropylene. Body portion  22  may be free of structural metal. In an exemplary embodiment, body portion  22  may comprise a material with a durometer greater than approximately 90 shore A in order to provide sufficient structural rigidity. Body portion  22  may have a generally U-shaped cross section. Body portion  22  may comprise a base  28  and first and second opposing walls  30 ,  32 . Wall  30  may be shorter or longer in length than wall  32 , thereby creating the U-shaped cross-section. Base  28  and first and second opposing walls  30 ,  32  define channel  34 . Channel  34  is configured to receive at least an edge of window panel  14 . 
         [0025]    Body portion  22  may be coextruded with a trim or overlay layer  36 . Overlay layer  36  is provided as a soft material (i.e., approximately equal to 70 shore A durometer or less) that may contact moveable window panel  14 . Overlay layer  36  may comprise a thermoplastic material. In an exemplary embodiment, overlay layer  36  may comprise a thermoplastic vulcanizate. Overlay layer  36  may extend along an outer surface of body portion  22 . In an exemplary embodiment, overlay layer  36  may cover an outer surface of base  28  and an outer surface of first and second walls  30 ,  32  of body portion  22 . Overlay layer  36  may also extend along an inner surface of first wall  30 . The overlay layer  36  may comprise a solid land  38  disposed in channel  34  on an inner surface of first wall  30 . Solid land  38  is provided for stabilizing moveable window panel  14 . Solid land  38  may stabilize moveable window panel  14  without fatigue or deformation over time (as may be likely with a rail stabilizer extending from an inner surface of first wall  30 ). At least a portion of solid land  38  may include a material  40  for reducing friction between moveable window panel  14  and division post  16 . Overlay layer  36  may also continue from solid land  38  along at least a portion of an inner surface of base  28 . In an embodiment, at least a portion of an inner surface of base  28  may include a material  42  for reducing friction between moveable window panel  14  and division post  16 . Overlay layer  36  may also extend along at least a portion of an inner surface of second post  32  of body portion  22 . 
         [0026]    Materials  40 ,  42  may comprise any material with a low coefficient of friction. For example, materials  40 ,  42  may comprise flocking or polyethyelene. Flocking may be comprised of a soft fibrous layer formed from a mixture of fiber and adhesive, which may be electrostatically coated onto division post  16 . Although flocking and polyethylene are described in detail, it is understood that various other materials may be used for reducing friction and remain within the spirit and scope of the invention. 
         [0027]    Overlay layer  36  defines first and second sealing wings  24 ,  26 . First and second sealing wings  24 ,  26  are provided for guiding moveable window panel  14  via contact in channel  34 . First sealing wing  24  forms a sealing surface on the outside surface of moveable window panel  14  along a rear edge of moveable window panel  14 . First sealing wing  24  extends from a free end  44  of first post  30  into channel  34 . First sealing wing  24  may comprise a different material than body portion  22 . In an exemplary embodiment, first sealing wing  24  may comprise a thermoplastic vulcanizate. In an exemplary embodiment, first sealing wing  24  may comprise a material with a durometer equal to or less than approximately  70  shore A. First sealing wing  24  may be coextruded with body portion  22 . First sealing wing  24  may comprise a portion of overlay layer  36  that is coextruded with body portion  22 . At least a portion of first sealing wing  24  may include a material  46  for reducing friction between moveable window glass panel  14  and division post  16 . 
         [0028]    Second sealing wing  26  forms a sealing surface on the inside surface of moveable window panel  14  along the rear edge of moveable window panel  14 . Second sealing wing  26  extends from a free end  48  of second post  32  into channel  34 . Second sealing wing  26  may comprise a different material than body portion  22 . In an exemplary embodiment, second sealing wing  26  may comprise a thermoplastic vulcanizate. In an exemplary embodiment, second sealing wing  26  may comprise a material with a durometer equal to or less than approximately 70 shore A. Second sealing wing  26  may be coextruded with body portion  22 . Second sealing wing  26  may comprise a portion of overlay layer  36  that is coextruded with body portion  22 . At least a portion of second sealing wing  26  may include a material  50  for reducing friction between moveable window glass panel  14  and division post  16 . 
         [0029]    First and second sealing wings  24 ,  26  may oppose each other and may be offset with respect to an axis  51 . Axis  51  may be generally perpendicular to the axis of movement of window panel  14  (i.e., axis  21 ). Accordingly, opposing sealing wings  24 ,  26  may be offset with respect to lateral axis  51 , thereby improving the stability of window panel  14 . As shown in  FIG. 3 , first sealing wing  24  may be disposed closer to base  28  than second sealing wing  26 . In some embodiments, second sealing wing  26  may be disposed closer to base  28  than first sealing wing  24 . 
         [0030]    First and second sealing wings  24 ,  26  may project in channel  34  toward base  28  of body portion  22 . In an exemplary embodiment, first sealing wing  24  may be configured for greater deflection toward base  28  of body portion  22  than second sealing wing  26 . For example, as shown in  FIG. 3 , first sealing wing  24  has a narrower hinge  52  that provides for greater deflection of sealing wing  24  than hinge  54  of second sealing wing  26 . 
         [0031]    Rear door assembly  10  may further include an integrated trim  20 . In an embodiment, integrated trim  20  may be securely attached to fixed window panel  18  by virtue of being molded thereon. A molded portion  56  of integrated trim  20  is provided to receive at least an edge of fixed window panel  18 . Molded portion  56  thereby connects fixed window panel  18  to division post  16  and provides tight positive retention of fixed window panel  18 . Molded portion  56  may comprise a thermoplastic vulcanizate (TPV), thermoplastic polyolefin (TPO), or polyvinyl chloride (PVC). Although these materials are mentioned in detail, it is understood by those of ordinary skill in the art that numerous other polymers may be used and remain within the spirit and scope of the invention. Division post  16  has an encapsulated portion  58  and a non-encapsulated portion  60 , the latter of which extends outside the mold cavity during fabrication. Mounting bracket  62  is provided as shown attached to division post  16  in the conventional matter. It is to be understood that additional mounting brackets and the like will ordinarily be present on rear door assembly  10 , but could apply to front doors. In addition, bracket  62  is shown as representative of all such mounting hardware. Bracket  62  may be placed directly in mold  74  and embedded in trim  56 , as shown in  FIG. 6 . 
         [0032]    Rear door assembly  10  may further include a fully integrated header glass run channel strip  64  and B-pillar portion  66 . Header glass run channel strip  64  extends from molded portion  56  of integrated trim  20 . B-pillar portion  66  may be attached to header glass run channel strip  64  at corner  68 , which will typically have an angle of approximately 90 to approximately 110 degrees. In most applications, header glass run channel strip  64  and B-pillar portion  66  will be extruded as either a single piece or as two separate pieces which are bonded together at corner  68 . In most applications, header glass run channel strip  64  and B-pillar portion  66  will be formed of ethylene propylene diene rubber (EPDM), styrene butadiene rubber (SBR) or other thermoset or thermoplastic polymers. Various processing aids and other additives may be appropriate for use in combination with the polymers. Integrated trim  20  may be formed of the same materials. As will be recognized by those of ordinary skill in the art, the length of header glass run channel strip  64  may be dictated by vehicle design, for example, from about 12 inches to about 36 inches. 
         [0033]    Outboard wing  72  of header glass run channel strip  64  and first sealing wing  24  may be bonded at corner  70 . Outboard wing  72  may be joined by the molded polymer to sealing wing  24  to form a continuous radial trim region which fits securely around and against the corner of moveable window panel  14 . An injection molded material may, therefore, fill in the space between outboard wing  72  and sealing wing  24  to form the radial portion at corner  70 . Header trim strip  64  and overlay layer  36  may have inside lips (i.e., second sealing wing  26  and the inboard wing (not shown) of header glass run channel strip  64 ) and outside lips (i.e., first sealing wing  24  and outboard wing  72  of header glass run channel strip  64 ) for sealing moveable window panel  14 . The inside lips are similarly jointed at the radius (i.e., corner)  70  by the injection molded polymer. 
         [0034]    Referring now to  FIG. 4  of the drawings, a fragment of mold  74  is shown having a mold space  76  which comprises several regions or spaces. Mold space  76  is configured to receive and accommodate fixed window panel  18  (shown in phantom), a portion of division post  16 , and an end portion of header glass run channel strip  64  as inserts in the mold cavity. Accordingly, mold space  76  comprises fixed widow panel receiving space  78 , division post receiving space  80 , and header glass run channel strip receiving space  82 . The geometry of these various insert regions or spaces in mold  74  may be a function of the geometry of the inserts. Mold  74  may be provided with the appropriate seal region to retain the molded polymeric material within mold space  76 . 
         [0035]    Referring now to  FIG. 5  of the drawings, a fragmentary portion of mold space  76  is shown in phantom to highlight the relative placement of fixed window panel  18 , division post  16 , and end  78  of header glass run channel strip  64 . Mold space  76  may be provided to accept end  78  of header glass run channel strip  64  so that once the thermoset or thermoplastic material (for example, EPDM) is injected, the molded thermoset or thermoplastic material joins with the thermoset or thermoplastic header glass run channel strip  64  and division post  16  and encapsulates fixed window panel  18  to form a single unitary integrated trim  20 . In an exemplary embodiment, header glass run channel strip  64  may extend into mold space  76  above fixed glass  18  an in some cases reach the belt line. Mold slides may be used to facilitate injection and sealing of the inserts, particularly header glass run channel strip  64  and division post  16  in the mold. The bonding of the molded portion of trim  20  to header glass run channel strip  64  and division post  16  may result in integral joints. 
         [0036]    The various injection molding parameters, such as the temperature of the polymer, injection and dwell times, the pressure, and gating will be recognized by those skilled in the art based on the teachings provided by the present invention. For example, a cure (vulcanizing) temperature of from about 320° F. to about 500° F. is appropriate for use with EPDM. It is generally preferred to clean and prime the edges of fixed window panel  18  prior to molding. 
         [0037]    Although particular embodiments of the invention have been described in detail herein with reference to the accompanying drawings, it is to be understood that the invention is not limited to those particular embodiments, and that various changes and modifications may be effected therein by one skilled in the art without departing from the scope or spirit of the invention as defined in the appended claims.