Patent Publication Number: US-2019193535-A1

Title: Resin back door for vehicle

Description:
CROSS REFERENCE TO RELATED APPLICATION 
     This application claims priority to Japanese Patent Application No. 2017-245372 filed on Dec. 21, 2017, which is incorporated herein by reference in its entirety including the specification, claims, drawings, and abstract. 
     TECHNICAL FIELD 
     The present disclosure relates to a structure of a resin back door for a vehicle. 
     BACKGROUND 
     Vehicles which include opening portions positioned at rear end portions thereof and that are opened and closed by back doors have been widely used, facilitating access to cargo spaces positioned in back of rear seats of the vehicles. 
     Furthermore, in recent years, many vehicle doors made of resin have been used. The doors made of resin have a reduced weight but ensuring rigidity is difficult as compared with doors made from steel plate. For this reason, a structure has been proposed to mount a metal reinforcing member in a hollow space defined by a resin inner panel and a resin outer panel (e.g., see JP 5846036 B). 
     SUMMARY 
     Incidentally, in related art, a steel back door  300  as illustrated in  FIG. 6  includes a door interior trim  260  being a resin component constituting an interior design surface that is attached on the interior side. The steel back door  300  includes a steel frame  70  formed by a groove-shaped inner panel  71 , a hat-shaped outer panel  72 , and a groove-shaped reinforcing member  73  which are assembled by welding, and the door interior trim  260  attached to the frame  70  on the interior side of a door opening  78  of a back window  12 . The door interior trim  260  is mounted so as to be close to body interior trims  250  and  251  which are attached on the interior side of a body inner panel  216  positioned at a body rear end portion  210  and constitute a design surface. As illustrated in  FIG. 6 , a gap between the body interior trim  251  and the door interior trim  260  is reduced to s 2  so that a water-tight rubber  230  disposed between the steel back door  300  and the body rear end portion  210  is concealed from the interior, improving the appearance of a rear side of the vehicle when viewed from an interior of the vehicle. 
     In contrast, unlike the steel back door  300 , the door interior trim  260  as a separate component does not need to be attached to a resin back door, since a surface on the interior side of a resin inner panel constitutes a design surface. However, as illustrated in  FIG. 6 , a gap between the body interior trim  251  and the inner panel  71  increases to s 3  and the water-tight rubber  230  is sometimes seen from the interior, resulting in poor appearance of a rear side of the vehicle when viewed from an interior of the vehicle. 
     It is therefore an object of the present disclosure to provide a resin back door which improves the appearance of a rear side of a vehicle when viewed from an interior of the vehicle. 
     Solution to Problem 
     A resin back door according to an embodiment of the present disclosure is a resin back door for a vehicle for opening and closing a door opening at a body rear end portion. The resin back door includes a resin inner panel including a window frame portion for a back window opening positioned on an outer side in a vehicle width direction. In the resin back door, the window frame portion of the inner panel has a substantially groove-shaped cross-section, and includes a bottom portion abutting on a water-tight rubber attached to a peripheral edge of the door opening, and an inner vertical wall positioned on an inner side in a vehicle width direction to be connected to the bottom portion. The bottom portion has a projecting portion projecting toward the door opening at an inner end in a vehicle width direction. When the door opening is closed, a surface of the inner vertical wall on an inner side in a vehicle width direction is substantially flush with an interior trim surface attached to an inner periphery of the door opening. 
     Advantageous Effects of Invention 
     According to an embodiment of the present disclosure, a resin back door for a vehicle improves the appearance of a rear side of a vehicle when viewed from an interior of the vehicle. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
       Embodiment(s) of the present disclosure will be described by reference to the following figures, wherein: 
         FIG. 1  is a perspective view of a vehicle to which a resin back door according to an embodiment is attached; 
         FIG. 2  is a cross-sectional view taken along line A-A (a cross-section of a left side portion of a body rear end portion) of  FIG. 1 ; 
         FIG. 3  is a perspective view of the resin back door according to an embodiment; 
         FIG. 4  is an exploded perspective view of a resin back door according to an embodiment; 
         FIG. 5  is a cross-sectional view of the cross-section taken along line A-A of  FIG. 1  (the cross-section of the left side portion of the body rear end portion) and a cross-section taken along line B-B of  FIG. 3  (a cross-section of a left window frame portion of the resin back door) when a door opening is closed by the resin back door; and 
         FIG. 6  is a cross-sectional view of a cross-section of a left side portion of a body rear end portion and a cross-section of a left window frame portion of a steel back door when a door opening is closed by the steel back door according to the related art. 
     
    
    
     DESCRIPTION OF EMBODIMENTS 
     Hereinafter, a resin back door  100  of a vehicle  200  according to the present embodiment will be described with reference to the drawings. As illustrated in  FIG. 1 , the resin back door  100  is a hatch door turnably attached to a roof panel  13  of a body rear end portion  210  of the vehicle  200  via a pair of right and left hinges  75  provided at an upper end portion of the resin back door  100 , and turned vertically about the hinges  75  as indicated by an arrow  99  to open and close a door opening  220  defined in the body rear end portion  210 . 
     As illustrated in  FIG. 2 , the body rear end portion  210  has a left side portion  210 L including a body outer panel  211 , a body inner panel  212 , a trough panel  213 , a water-tight rubber  230 , and an inner garnish  240  as an interior trim. The body outer panel  211  constitutes a design surface  210   a  positioned on the outside of the body rear end portion  210 . The body inner panel  212  is a panel positioned on an interior side. The trough panel  213  is a panel attached between the body outer panel  211  and the body inner panel  212  to constitute a groove-shaped trough  14 . As illustrated in  FIGS. 1 and 2 , between the trough  14  and an inner panel  20  of the resin back door  100 , damper stays  60  are mounted to reduce an operation force for opening the resin back door  100  and maintain the opening state. The right side and the left side are described as the right side and the left side as viewed from a rear side of the vehicle. 
     As illustrated in  FIG. 2 , the trough panel  213  has an inner end in a vehicle width direction having an L-shaped flange projecting to the rear side of the vehicle or toward the resin back door  100 . Furthermore, the body inner panel  212  has a rear end in a vehicle longitudinal direction overlappingly connected to the flange of the trough panel  213  to form a collar portion  212   e  protruding to the rear side of the vehicle or toward the resin back door  100 . The collar portion  212   e  defines a peripheral edge of the door opening  220 . The water-tight rubber  230  is attached to a vehicle-rearward end of the collar portion  212   e.    
     The water-tight rubber  230  is a packing interposed between the collar portion  212   e  and the inner panel  20  to prevent intrusion of water into the interior from between the resin back door  100  and the body rear end portion  210 . The water-tight rubber  230  includes a main body  230   a , a packing portion  230   b , and a lip  230   c . The main body  230   a  includes a holding lip internally provided to hold the collar portion  212   e  from both sides. The packing portion  230   b , projecting to a vehicle-rearward side of the main body  230   a , is held and compressed between the collar portion  212   e  and the inner panel  20 . The lip  230   c  projects to the inner side in a vehicle width direction from the main body  230   a . As illustrated in  FIG. 2 , the water-tight rubber  230  is configured so that when the main body  230   a  is attached to the collar portion  212   e , the packing portion  230   b  projects toward the resin back door  100 . 
     The body inner panel  212  has an inner side positioned on an interior side in a vehicle width direction, and the inner garnish  240  is attached on the inner side. The inner garnish  240  is provided on the inner side of the collar portion  212   e  defining the peripheral edge of the door opening  220 , in a vehicle width direction. The inner garnish  240  includes an end portion  240   e  positioned on the rear side of the vehicle. The end portion  240   e  is held between the lip  230   c  of the water-tight rubber  230  and an outer surface of the main body  230   a  so that the end portion  240   e  does not move relative to the water-tight rubber  230  and the collar portion  212   e . The inner garnish  240  includes a design surface  240   a  on the inner side in a vehicle width direction or on the interior side to constitute an inner peripheral surface of the door opening  220 . 
     Although the left side portion  210 L of the body rear end portion  210  has been described above, a right side portion  210 R and the left side portion  210 L are symmetrical to each other and have the same configuration. 
     The resin back door  100  includes a resin upper outer panel  10  and a lower outer panel  15 , as illustrated in  FIG. 3 , and the resin inner panel  20  and a metal reinforcing member  40  fixed to the inner panel  20 , as illustrated in  FIG. 4 . The reinforcing member  40  includes a left reinforcing member  41 L, a right reinforcing member  41 R, a lower-side reinforcing member  47 , a left corner connecting member  46 L, and a right corner connecting member  46 R. 
     As illustrated in  FIG. 4 , the inner panel  20  has an upper side portion  21 , a left window frame portion  22 L and a right window frame portion  22 R, a lower left portion  23 L and a lower right portion  23 R, and a lower side portion  24 . The upper side portion  21  has a back window opening  35  which is defined in the center and to which the upper outer panel  10  is assembled above the back window opening  35 . The left window frame portion  22 L and a right window frame portion  22 R are positioned on the outer sides of the back window opening  35  in a vehicle width direction. The lower left portion  23 L and the lower right portion  23 R are positioned below the back window opening  35  on the outer sides in a vehicle width direction to receive the lower outer panel  15  assembled. On both right and left sides of the upper side portion  21  of the inner panel  20 , bolt holes  38  are provided to attach the hinges  75 . 
     The left reinforcing member  41 L has a closed-section structure having a substantially L shape along the upper side portion  21 , the left window frame portion  22 L, and the lower left portion  23 L of the inner panel  20 . The right reinforcing member  41 R has a closed-section structure having a substantially L shape along the upper side portion  21 , the right window frame portion  22 R, and the lower right portion  23 R of the inner panel  20 . The left reinforcing member  41 L includes an upper left shoulder portion  42 L, and an upper left arm portion  43 L and a lower left arm portion  44 L. The upper left shoulder portion  42 L is assembled to be opposed to the upper side portion  21  of the inner panel  20 . The upper left arm portion  43 L and the lower left arm portion  44 L are assembled to be opposed to the left window frame portion  22 L and the lower left portion  23 L of the inner panel  20 , respectively, to extend in a vehicle vertical direction. The upper left shoulder portion  42 L has an upper side provided with a recessed portion  42 U, and the recessed portion  42 U has bolt holes  48  for attaching a hinge. 
     The right reinforcing member  41 R is symmetrical to the left reinforcing member  41 L, and includes an upper right shoulder portion  42 R, and an upper right arm portion  43 R and a lower right arm portion  44 R, and the upper right shoulder portion  42 R has an upper side provided with a recessed portion  42 V in which bolt holes  48  are provided. 
     The left corner connecting member  46 L is a member having a substantially L shape to connect a lower end portion  45 L of the left reinforcing member  41 L and a left end  47 L of the lower-side reinforcing member  47 . The right corner connecting member  46 R is a member having a substantially L shape to connect a lower end portion  45 R of the right reinforcing member  41 R and a right end  47 R of the lower-side reinforcing member  47 . 
     In the resin back door  100 , bolts are inserted through the bolt holes  38  of the inner panel  20  and the bolt holes  48  in both of the left reinforcing member  41 L and the right reinforcing member  41 R, and nuts are fastened from the opposite side. Thus, the resin back door  100  is fastened to the hinges  75  fixed to right and left sides of the roof panel  13 . 
     As illustrated in  FIG. 5 , the upper left arm portion  43 L of the left reinforcing member  41 L, the upper portion of the lower outer panel  15 , and a back window glass  12   a  are assembled to the left window frame portion  22 L of the inner panel  20 . 
     The left window frame portion  22 L of the inner panel  20  includes a groove portion  22   a , an inner flange  22   c , and an outer flange  22   d . The groove portion  22   a  has a substantially groove-shaped cross-section of substantially U shape recessed to the front side in a vehicle longitudinal direction. The groove portion  22   a  includes a bottom portion  22   b  on the front side in a vehicle longitudinal direction, an inner vertical wall  22   h  on the inner side in a vehicle width direction, and an outer vertical wall  22   j  on the outer side in a vehicle width direction. 
     The bottom portion  22   b  includes a bottom surface  22   k  and a projecting portion  22   m . The bottom surface  22   k  is positioned on the front side in a vehicle longitudinal direction and abuts on the water-tight rubber  230  attached to the peripheral edge of the door opening  220  of the body rear end portion  210 . The projecting portion  22   m  projects toward the door opening  220  at an inner end in a vehicle width direction. The inner vertical wall  22   h  on the inner side in a vehicle width direction of the groove portion  22   a  is connected to the projecting portion  22   m  of the bottom portion  22   b  and extends to the rear side in a vehicle longitudinal direction. The outer vertical wall  22   j  on the outer side in a vehicle width direction of the groove portion  22   a  extends to the rear side from the bottom portion  22   b  in a vehicle longitudinal direction to be connected to the inner flange  22   c . The inner flange  22   c  bends and extends to the outer side in a vehicle width direction, from a rear end of the outer vertical wall  22   j  of the bottom portion  22   b  positioned in a vehicle longitudinal direction, and is connected to the outer flange  22   d  extending to the outer side in a vehicle width direction. An outer side of the outer flange  22   d  in a vehicle width direction is formed as a parting portion  22   e  positioned on the outer side in a vehicle width direction of the inner panel  20 . 
     An upper portion of the lower outer panel  15  has an outer portion in a vehicle width direction assembled to the outer flange  22   d  of the left window frame portion  22 L of the inner panel  20  with an adhesive  51  at a strip-shaped portion projecting upward on the outer side in a vehicle width direction, and an inner side portion in a vehicle width direction extends to the inner side in a vehicle width direction to cover the groove portion  22   a  of the inner panel  20 . A hollow space  18  is formed between the upper portion of the lower outer panel  15  and the groove portion  22   a  of the inner panel  20 , and the upper left arm portion  43 L of the left reinforcing member  41 L is disposed in the hollow space  18 . 
     The upper left arm portion  43 L of the left reinforcing member  41 L has a substantially square annular closed-section structure, and includes collar portions  43   c  and  43   d  projecting to the outer side in a vehicle width direction and to the rear side in a vehicle longitudinal direction, respectively. The upper left arm portion  43 L of the left reinforcing member  41 L includes an inner plate  43   a  and an outer plate  43   b . The inner plate  43   a  is positioned near the inner panel  20  and includes collars having a substantially U shape extending to the outer side in a vehicle width direction and to the rear side in the vehicle longitudinal direction, and the outer plate  43   b  has a bending plate formed to close an opening side of the inner plate  43   a  of U-shape and includes collars on both sides to be assembled to the collars of the inner plate  43   a . Joint portions between the collars of the inner plate  43   a  and the collars of the outer plate  43   b  constitute the collar portions  43   c  and  43   d , respectively. A surface  43   f  of a bottom portion of the inner plate  43   a  of the left reinforcing member  41 L is arranged to a surface  22   f  of the groove portion  22   a  of the inner panel  20  leaving a gap d 1  and is fixed thereto with an adhesive  50 . A surface  43   g  of the collar portion  43   c  of the left reinforcing member  41 L near the inner panel  20  is arranged at a surface  22   g  of the inner flange  22   c  of the inner panel  20  leaving a gap d 2  and is fixed thereto with an adhesive  50 . The outer plate  43   b  and the upper part of the lower outer panel  15  are separated from each other. The lower outer panel  15  is assembled onto the outer flange  22   d  of the inner panel  20  via a urethane material  52 , and the back window glass  12   a  is attached onto the rear side of the upper portion of the lower outer panel  15  in a vehicle longitudinal direction. 
     As illustrated in  FIG. 5 , when the door opening  220  is closed by the resin back door  100 , the bottom surface  22   k  of the bottom portion  22   b  of the inner panel  20  presses the packing portion  230   b  of the water-tight rubber  230  against the collar portion  212   e  at the peripheral edge of the door opening  220 . Furthermore, an end of the projecting portion  22   m  of the bottom portion  22   b  on the side of the door opening  220  extends toward the door opening  220  to a position overlapping the packing portion  230   b  in a vehicle width direction. A gap between the end of the projecting portion  22   m  and the end portion  240   e  of the inner garnish  240  on the rear side of the vehicle decreases to s 1 . 
     Furthermore, a design surface  22   n  of the inner vertical wall  22   h  on the inner side in a vehicle width direction is substantially flush with the design surface  240   a  of the inner garnish  240  on the inner side in a vehicle width direction or on the interior side, where the inner garnish  240  constitutes the design surface of the inner periphery of the door opening  220 . 
     As described above, when the door opening  220  is closed by the resin back door  100 , the gap between the end of the projecting portion  22   m  of the bottom portion  22   b  of the inner panel  20  and the end portion  240   e  of the inner garnish  240  on the rear side of the vehicle decreases. Thus, the water-tight rubber  230  is concealed when viewing the rear side of the vehicle from the interior, and the appearance of the rear side of the vehicle when viewed from the interior can be improved. Furthermore, the design surface  22   n  of the inner vertical wall  22   h  on the inner side in a vehicle width direction is substantially flush with the design surface  240   a  of the inner garnish  240  as an interior trim surface on the inner side in a vehicle width direction or on the interior side so that the design surface  22   n  of the inner panel  20  on the inner side in a vehicle width direction constitutes an integrated design surface extending to the design surface  240   a  in the door opening  220  on the inner side in a vehicle width direction. Thus, the configuration provides an integrated design of the interior inner surface and improvement in the appearance.