JP2013082361A - Back door structure for vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a back door structure for a vehicle, which can prevent or restrain both end sides of the upper end of a back door from warping up.SOLUTION: The terminal position on the vehicle-width-direction outside of a door hinge 22 is set as a position on the vehicle-width-direction inside with respect to a terminal position on the vehicle-width-direction outside of the upside of the back door 30. The door hinge 22 is attached to a door hinge attachment part 36 in a position in which the relationship of B≥0.7A is established in the case where A represents 1/2 of the length of the upside of the back door 30 and where B represents a vehicle-width-direction distance between a vehicle-width-direction center position of the door hinge 22 and a vehicle-width-direction center position of the upside of the back door 30. Additionally, an upper end reinforcing part 46A of a hinge reinforcement 46 includes a second reinforcing part 50 which is elongated to the vehicle-width-direction inside from a first reinforcing part 48 for reinforcing the door hinge attachment part 36.

Description

  The present invention relates to a vehicle back door structure applied to a back door at the rear of a vehicle.

  In the back door, the upper end of the door is attached to the upper part of the vehicle body via a door hinge (see, for example, Patent Document 1), and the door closed state is maintained by locking the lower end of the door to the lower part of the vehicle body. In such a back door, in order to reduce the weight, for example, a non-ferrous material may be used for the panel, or the panel may be thinned.

JP2011-121479A

  However, in this structure, depending on the rigidity of the upper end portion of the back door, there may be a case where both end portions of the upper end portion of the back door are deformed so as to warp.

  In view of the above fact, an object of the present invention is to obtain a vehicular back door structure capable of preventing or suppressing warping of both end portions of the upper end portion of the back door.

  The vehicle back door structure of the present invention described in claim 1 is provided at a back door capable of opening and closing a back door opening at the rear of the vehicle, and at both ends of the upper end of the back door in the vehicle width direction, A pair of left and right door hinges that connect the back door and the upper part of the vehicle body, and a vehicle position that is provided on the back door and that has a terminal position outside the vehicle width direction of the door hinge relative to a terminal position outside the vehicle width direction on the upper side of the back door. A half of the length of the upper side of the back door is set to A, and the center position in the vehicle width direction of the door hinge and the vehicle width direction center position of the upper side of the back door in the vehicle width direction. When the distance is B, the door hinge attachment portion to which the door hinge is attached is provided at a position where the relationship of B ≧ 0.7A is established.

  According to the vehicle back door structure of the present invention as set forth in claim 1, the upper end of the back door is connected to the upper part of the vehicle body by a pair of left and right door hinges, and the back door opening at the rear of the vehicle can be opened and closed. It has become. For this reason, in the closed state of the back door, a load for supporting the weight of the back door to the upper part of the vehicle body acts on the door hinge mounting portion at the upper end of the back door via the door hinge. And since the vehicle width direction position of the gravity center of a back door exists in the vehicle width direction position between door hinge attaching parts, the said load hangs down between door hinge attaching parts by using a pair of left and right door hinges as a fulcrum. An attempt is made to warp a portion on the outer side in the vehicle width direction from the door hinge mounting portion.

  On the other hand, in the present invention, the door hinge has a terminal position on the vehicle width direction outer side of the door hinge as a position on the vehicle door side in the vehicle width direction on the vehicle door in the vehicle width direction outside on the upper side of the back door. The relation of B ≧ 0.7A, where A is a half length of the door and B is the distance in the vehicle width direction between the center position of the door hinge in the vehicle width direction and the center position of the upper side of the back door in the vehicle width direction. The attachment position to the door hinge attachment portion is set at a position where is established. For this reason, compared with the contrast structure set to B <0.7A, the weight of the back door is supported on the upper part of the vehicle body at the outer side in the vehicle width direction, so that the vehicle width direction outer side than the door hinge mounting portion. The amount of warping of the part of can be suppressed.

  According to a second aspect of the present invention, there is provided a vehicle back door structure according to the first aspect of the present invention, wherein the door inner panel includes an inner plate of the back door and includes the door hinge mounting portion, and the door inner panel. A first reinforcing portion that is fixed to the door inner panel and reinforces the door hinge mounting portion of the door inner panel, and extends inward in the vehicle width direction from the first reinforcing portion and forms a closed cross section with the door inner panel. A pair of left and right hinge reinforcements including a second reinforcing portion that reinforces a portion on the inner side in the vehicle width direction of the door hinge mounting portion in the door inner panel.

  According to the vehicle back door structure of the present invention described in claim 2, a pair of left and right hinge reinforcements are fixed to the door inner panel constituting the inner plate of the back door. In the hinge reinforcement, the first reinforcing portion reinforces the door hinge mounting portion in the door inner panel, the second reinforcing portion extends from the first reinforcing portion inward in the vehicle width direction, and forms a closed section with the door inner panel. A portion on the inner side in the vehicle width direction with respect to the door hinge mounting portion of the door inner panel is reinforced. For this reason, even if the load which tries to hang down between door hinge attaching parts acts on a pair of left and right door hinges as a fulcrum in the closed state of the back door, the amount of sag between the door hinge attaching parts is caused by the second reinforcing part. It can be suppressed. As a result, the bending amount (curve change amount) of the upper end portion of the door inner panel is suppressed, and the amount of warping of the portion on the outer side in the vehicle width direction from the door hinge mounting portion is also suppressed.

  As described above, according to the vehicular back door structure according to claim 1 of the present invention, the excellent effect of preventing or suppressing warping of both end portions of the upper end portion of the back door can be achieved. Have.

  According to the vehicle back door structure according to claim 2, it is possible to prevent or suppress the warping of both ends of the upper end portion of the back door by suppressing the amount of sag between the door hinge mounting portions. It has the effect.

1 is a perspective view showing a vehicle rear portion including a back door to which a vehicle back door structure according to an embodiment of the present invention is applied. 1 is a front view showing a back door to which a vehicular back door structure according to an embodiment of the present invention is applied as seen from the front side of the door and in a state seen through an outer unit. It is explanatory drawing for demonstrating distribution of the distortion amount of the back door to which the vehicle back door structure which concerns on one Embodiment of this invention was applied. 3A is a distortion distribution in a plan view of the present embodiment, FIG. 3B is a distortion distribution of the present embodiment in a front view of the door (vehicle rear view), and FIG. FIG. 3D shows the distribution of the strain amount in the front view (the vehicle rear view) of the contrast structure, respectively. It is explanatory drawing for demonstrating the installation state of the back door to which the vehicle back door structure which concerns on one Embodiment of this invention was applied. It is a graph which shows the relationship between the attachment position of a door hinge, and the curve variation | change_quantity in a back door upper end part.

(Configuration of the embodiment)
A vehicle back door structure according to an embodiment of the present invention will be described with reference to FIGS. In these drawings, an arrow FR appropriately shown indicates the vehicle front side, an arrow UP indicates the vehicle upper side, and an arrow W indicates the vehicle width direction. Moreover, the door width direction (door left-right direction) of the back door 30 is the same direction as the vehicle width direction.

  FIG. 1 is a perspective view of a vehicle rear portion 10 of an automobile. As shown in FIG. 1, a back door opening 12 (also referred to as “rear gate”) is formed in the vehicle rear portion 10 as a vehicle body opening that opens rearward in the vehicle front-rear direction. A back door 30 (which is an element grasped as an “opening / closing body” in a broad sense) for opening and closing 12 is provided. Rear pillars 14 are erected on both sides of the back door opening 12, and a rear roof header portion 16 is disposed substantially along the vehicle width direction on the upper edge side of the back door opening 12. On the edge side, the lower back portion 18 is disposed substantially along the vehicle width direction.

  The back door 30 includes a back door main body 30A at the lower part of the door and a back door frame part 30B at the upper part of the door. A back door window glass 32B (also referred to as “rear glass”), which will be described later, is mounted on the back door frame portion 30B. Both ends on the vehicle width direction outer side at the upper end portion of the back door 30 are attached to the rear roof header portion 16 at the upper part of the vehicle body by a pair of left and right door hinges 22.

  FIG. 2 is a front view of the back door 30 as viewed from the door front side (outer surface side) and a state where the outer unit 32 indicated by a two-dot chain line is seen through. The configuration on the right side in the figure and the configuration on the left side in the figure are basically symmetrical. For this reason, in FIG. 2, the provision of the reference numerals to the constituent parts on the right side in the drawing is omitted as appropriate.

  As shown in FIG. 2, the door hinge 22 that connects the back door 30 and the rear roof header portion 16 includes a door-side attachment member 22 </ b> A fastened and fixed to the back door 30 with a bolt 52, and the rear roof header portion 16. The vehicle body side attachment member 22C is fastened and fixed by a bolt 54. The mounting surface of the vehicle body side mounting member 22C is arranged substantially horizontally as an example in the present embodiment. When the back door 30 is closed, the mounting surface of the door side mounting member 22A and the mounting surface of the vehicle body side mounting member 22C Are arranged to intersect. On the other hand, in FIG. 2, in order to show the configuration in an easy-to-understand manner, the mounting surface of the door side mounting member 22A and the mounting surface of the vehicle body side mounting member 22C are arranged on the same plane. The door hinge 22 and the like in a state where the door 30 is in a substantially horizontal posture are illustrated.

  A pair of left and right bolt insertion holes (holes overlapping 48B) are formed through the attachment portion of the door side attachment member 22A for insertion of the bolt 52, and the attachment portion of the vehicle body side attachment member 22C is for insertion of the bolt 54. A pair of left and right bolt insertion holes 56 are formed through. The door side mounting member 22A and the vehicle body side mounting member 22C are coupled to each other via a hinge pin 22B having the vehicle width direction as an axial direction so as to be relatively rotatable. The arrangement of the door hinge 22 will be described later in detail.

  The back door 30 shown in FIG. 1 can open and close the back door opening 12 by being rotationally moved about the axis of the hinge pin 22B (see FIG. 2) of the door hinge 22. That is, the back door 30 is movable between a closed position (the state shown in FIG. 1) for closing the back door opening 12 and an open position (not shown) for opening the back door opening 12.

  The vehicle width direction middle portion of the lower end portion of the back door 30 is locked to the lower portion of the vehicle body by the door lock mechanism 24. The door lock mechanism 24 includes a lock mechanism portion 24A attached to the back door 30 side and a striker 24B attached to the lower back portion 18 side. The lock mechanism portion 24A can be locked to the striker 24B, and the back door 30 is held in a closed state by locking the lock mechanism portion 24A to the striker 24B.

  In addition, dampers 26 are attached to both ends in the vehicle width direction of the middle portion of the back door 30 in the vertical direction. The pair of dampers 26 are attached to the lower side of both sides of the back door frame 30B, and are attached to the middle of the back door opening 12 at the middle in the vertical direction on both sides of the back door opening 12. And a piston. In the closed state of the back door 30, the damper 26 has both ends in the vehicle width direction of the intermediate portion in the vertical direction of the back door 30 outward from the passenger compartment (a direction including components on the vehicle rear side, in the direction of arrow A in the present embodiment). While energizing, it extends while rotating according to the opening degree of the back door 30. When the damper 26 extends, the opening operation force of the back door 30 is reduced and the open state is maintained.

  On the other hand, as shown in FIG. 2, the back door 30 includes an outer unit 32 disposed on the door outer side (vehicle compartment outer side), and a door inner panel 34 disposed on the door inner side (vehicle interior side). It consists of

  The outer unit 32 includes a resin door outer panel 32A, a back door window glass 32B, and a resin rear spoiler 32C. The door outer panel 32 </ b> A constitutes an outer plate (door outer side portion) of the back door main body 30 </ b> A (see FIG. 1) in the back door 30 and is disposed at the lower portion of the back door 30. The back door window glass 32B is disposed on the upper portion of the back door 30 by being bonded to the upper end portion of the door outer panel 32A. Further, the rear spoiler 32C is disposed on the upper end portion of the back door 30 by being bonded to the upper end portion of the back door window glass 32B.

  On the other hand, the door inner panel 34 is made of resin and constitutes the inner plate (door inner portion) of the back door 30, and the door inner panel constituting the inner plate of the back door main body 30A (see FIG. 1). A main body portion 34A and a door inner panel frame portion 34B constituting the back door frame portion 30B (see FIG. 1) are provided. The door inner panel 34 and the outer unit 32 are arranged to face each other, and the outer peripheral edge portions are joined with an adhesive. Thus, the back door 30 according to the present embodiment is a resin back door that is advantageous for weight reduction.

  An annular bead 42 is formed on the door inner panel 34 so as to go around the outer periphery. The annular bead 42 is formed to have a concave shape toward the outside of the door (a convex shape toward the vehicle interior side). Moreover, the vehicle width direction intermediate part of the lower end part of the door inner panel 34 (door inner panel main-body part 34A) is made into the lock mechanism attachment part 38 to which 24A of lock mechanism parts mentioned above are attached. Furthermore, the both ends in the vehicle width direction of the middle portion in the vertical direction of the door inner panel 34 have a surface (a surface opposite to the surface shown in FIG. 2) directed toward the vehicle interior as the damper mounting portion 40. The damper 26 (see FIG. 1) described above is attached to the damper attachment portion 40.

  On the other hand, the upper end portion of the door inner panel 34 (door inner panel frame portion 34B) has a pair of left and right door hinge attachment portions 36 at both ends in the vehicle width direction, and the door side attachment member 22A of the door hinge 22 described above is attached thereto. The door hinge mounting portion 36 has a bolt insertion hole (a hole overlapping the reference numeral 48B) formed in a pedestal portion protruding to the outside of the door (opposite the vehicle interior side), and a door of the pedestal portion of the door hinge mounting portion 36. On the outer surface side, the upper end portion of the hinge reinforcement 46 is overlapped in a surface contact state.

  The pair of left and right hinge reinforcements 46 are made of metal (for example, steel), and are high-strength and high-rigidity reinforcing members bent in a substantially L shape in a front view. These hinge reinforcements 46 are fixed by bolt fastening (not shown) along the annular bead 42 at a portion from the left and right upper end portions of the outer peripheral portion of the door inner panel 34 to the lower portion of the outer end portion in the vehicle width direction. That is, the hinge reinforcement 46 includes an upper end reinforcing portion 46A disposed at the upper end portion of the door inner panel 34 and a side reinforcing portion 46B disposed at the outer end portion of the door inner panel 34 in the vehicle width direction. .

  The upper end reinforcing portion 46 </ b> A includes a first reinforcing portion 48 that reinforces the door hinge mounting portion 36 in the door inner panel 34. The first reinforcing portion 48 is a pedestal portion 48A in which a portion corresponding to the pedestal portion of the door hinge mounting portion 36 is projected to the door outer side (the side opposite to the vehicle interior side). The pedestal portion 48A is formed with a bolt insertion hole 48B at a portion corresponding to the bolt insertion hole of the door hinge mounting portion 36. And the door hinge 22 is piled up in the surface contact state on the door inner surface side (vehicle interior side) of the pedestal portion of the door hinge mounting portion 36, and the door hinge 22 is inserted by the bolt 52 etc. inserted into the bolt insertion hole (48B etc.). Fastened to the door inner panel 34 and the hinge reinforcement 46.

  The first reinforcing portion 48 is formed with a first reinforcing bead 48C on the lower side in the door vertical direction with respect to the pedestal portion 48A. 48 C of 1st reinforcement beads are extended so that the vehicle width direction may be made into a longitudinal direction, and it is formed so that it may become convex shape on the door outer side. The first reinforcing portion 48 is fixed to the door inner panel 34 by bolt fastening (not shown) at the lower portion in the door vertical direction with respect to the outer portion of the first reinforcing bead 48C in the vehicle width direction. Accordingly, the first reinforcing portion 48 forms a closed cross section with the door inner panel 34.

  Further, the upper end reinforcing portion 46 </ b> A of the hinge reinforcement 46 includes a second reinforcing portion 50 that extends from the first reinforcing portion 48 inward in the vehicle width direction. In the second reinforcement portion 50, a second reinforcement bead 50A is formed at a portion on the inner side in the vehicle width direction with respect to the base portion 48A and the first reinforcement bead 48C. The second reinforcing bead 50 </ b> A extends substantially in the vertical direction of the door, and is formed to have a convex shape toward the outside of the door. As for the 2nd reinforcement part 50, the site | part of the vehicle width direction inner side part with respect to the upper part of the 2nd reinforcement bead 50A and the both sides of the left and right sides and the lower part of the 2nd reinforcement bead 50A is bolted (illustration omitted). It is fixed to. Accordingly, the second reinforcing portion 50 forms a closed cross section with the door inner panel 34 and reinforces a portion of the door inner panel 34 on the inner side in the vehicle width direction than the door hinge mounting portion 36.

  Next, the setting position of the door hinge mounting portion 36, in other words, the mounting position (arrangement position) of the door hinge 22 will be described.

  The terminal position on the outer side in the vehicle width direction of the door hinge 22 is a position on the inner side in the vehicle width direction relative to the terminal position on the upper side of the back door 30 on the outer side in the vehicle width direction. Further, the door hinge 22 has a length of 1/2 of the upper side of the back door 30 as A, and the distance in the vehicle width direction between the center position of the door hinge 22 in the vehicle width direction and the center position of the upper side of the back door 30 in the vehicle width direction. In the case of B, it is attached to the door hinge attachment portion 36 at a position where the relationship of B ≧ 0.7A is established. More specifically, in this embodiment, length A = 472 (mm) and distance B = 345 (mm) are set as an example.

  Further, the distance (pitch) P1 between the center points of the bolt insertion holes 56 of the vehicle body side mounting member 22C in the door hinge 22 is preferably 23 mm or more, and is set to 26 mm as an example in the present embodiment. Further, the distance (pitch) P1 between the center points of the bolt insertion holes 56 is preferably 5% or more with respect to the length A, and is set to about 5.5% with respect to the length A in this embodiment. . Further, the center point distance (pitch) P2 of the bolt insertion hole (hole overlapping the reference numeral 48B) of the door side attachment member 22A in the door hinge 22 is preferably 46 mm or more, and is set to 67 mm as an example in the present embodiment.

(Operation and effect of the embodiment)
Next, the operation and effect of the above embodiment will be described.

  As shown in FIG. 1, the back door 30 has an upper end connected to the rear roof header portion 16 by a pair of left and right door hinges 22 so that the back door opening 12 of the vehicle rear portion 10 can be opened and closed. . Therefore, when the back door 30 is closed, the door hinge mounting portion 36 at the upper end portion of the back door 30 shown in FIG. 2 supports the weight of the back door 30 to the rear roof header portion 16 via the door hinge 22. The load of acts. Since the vehicle width direction position of the center of gravity of the back door 30 is in the vehicle width direction position between the door hinge mounting portions 36, the load is between the door hinge mounting portions 36 with the pair of left and right door hinges 22 as fulcrums. Is hung down to warp the portion outside the door hinge mounting portion 36 in the vehicle width direction.

  Further, since the damper 26 urges the back door 30 to the outside of the vehicle compartment when the back door 30 is closed, the urging force of the damper 26 acts on the upper end of the back door 30 in addition to the weight of the back door 30. To do. On the other hand, the resin door inner panel 34 is less rigid than the metal door inner panel, and therefore, the upper end of the panel is easily deformed compared to the metal door inner panel.

  On the other hand, in the present embodiment, the door hinge 22 has the terminal position on the outer side in the vehicle width direction of the door hinge 22 as the position on the inner side in the vehicle width direction on the upper side of the back door 30, and When the length of the upper side of the back door 30 is A, and the distance in the vehicle width direction between the center position of the door hinge 22 in the vehicle width direction and the center position of the upper side of the back door 30 is B, The attachment position to the door hinge attachment portion 36 is set at a position where the relationship of B ≧ 0.7A is established. For this reason, compared with the contrast structure set to B <0.7A, the rear door header 16 supports the weight of the back door 30 on the outer side in the vehicle width direction. As a result, the amount of warping of the outer portion in the vehicle width direction is suppressed.

  In the present embodiment, the hinge reinforcement 46 includes a first reinforcing portion 48 that reinforces the door hinge mounting portion 36 in the door inner panel 34, and a second reinforcing portion 50 that extends inward in the vehicle width direction from the first reinforcing portion 48. In addition, a closed cross section is formed with the door inner panel 34 to reinforce a portion of the door inner panel 34 on the inner side in the vehicle width direction than the door hinge mounting portion 36. For this reason, even if the load which tries to hang down between the door hinge attaching parts 36 by using the left and right door hinges 22 as fulcrums when the back door 30 is closed, the second reinforcing part 50 causes the door hinge attaching parts 36 to The amount of sag between them is suppressed. As a result, the bending amount (curve change amount) of the upper end portion of the door inner panel 34 is suppressed, and the amount of warping of the portion on the outer side in the vehicle width direction from the door hinge mounting portion 36 is also suppressed.

  Here, a supplementary explanation will be given with reference to FIGS. FIG. 3 shows the distribution of strain of the back door in the closed state. That is, FIG. 3A shows the distribution of distortion in a plan view of the present embodiment, FIG. 3B shows the distribution of distortion in the front view of the door (the vehicle rear view), and FIG. (C) shows the distribution of strain amount in a plan view of the contrast structure, and FIG. 3 (D) shows the distribution of strain amount in the front view (vehicle rear view) of the contrast structure. In the figure, the denser (darker) dots, the greater the amount of distortion.

  3 (C) and 3 (D), the half length of the upper side of the back door is 470 mm, the center position of the door hinge in the vehicle width direction and the center position of the back door in the vehicle width direction. The distance in the vehicle width direction is 300 mm, the distance between the center points of the bolt insertion holes of the vehicle body side mounting member in the door hinge (the distance corresponding to the pitch P1) is 22 mm, and the distance between the center points of the bolt insertion holes in the door side mounting member in the door hinge (Distance corresponding to the pitch P2) is set to 60 mm. The contrast structure is the same as that of the vehicle back door structure according to the present embodiment in other respects.

  As shown in FIGS. 3 (C) and 3 (D), in the back door of the contrast structure (see the two-dot chain line), the left and right corner portions on the upper portion of the back door window glass and the continuous portion thereof are greatly distorted. This indicates that the distortion on the upper end side of the resin door inner panel propagated to the outer unit. On the other hand, as shown in FIGS. 3A and 3B, in the back door 30 (see the solid line) to which the vehicle back door structure according to the present embodiment is applied, the distortion of the same part is shown. The amount is suppressed.

  On the other hand, in each graph shown in FIG. 4, the ASSY composed of the door inner panel (34) and the outer unit (32) is attached to the vehicle body rear portion (10) by the door hinge (22) and the door lock mechanism (24). It shows how much the position is shifted when the back door (30) is closed with the interior and dampers (26) fully equipped to the ASSY with respect to the reference position.

  The solid line in the graph indicates the measurement result of the resin back door 30 to which the vehicle back door structure according to this embodiment is applied, and the two-dot chain line in the graph indicates the contrast structure (the contrast described in FIG. 3). The measurement result of the resin-made back door to which (structure) was applied is shown. 4 (A) and 4 (B) are the left side edge of the door, FIGS. 4 (C) and 4 (D) are the right side edge of the door, and FIGS. 4 (E) and 4 (F) are the upper edge of the door. 4 (G) and 4 (H) are graphs for the lower edge of the door.

  Moreover, the vertical axis | shaft of FIG. 4 (A), FIG. 4 (B), FIG.4 (C), and FIG.4 (D) has shown the height position of the vehicle up-down direction. The horizontal axes in FIGS. 4A and 4D indicate the amount of displacement (deviation amount) in the vehicle longitudinal direction, and the horizontal axes in FIGS. 4B and 4C indicate the vehicle vertical direction. The amount of displacement (the amount of deviation) is shown.

  Moreover, the horizontal axis of FIG.4 (E), FIG.4 (F), FIG.4 (G), and FIG.4 (H) has shown the position of the vehicle width direction. 4 (E) and FIG. 4 (G), the vertical axis indicates the amount of displacement (deviation amount) in the vehicle vertical direction, and the vertical axis in FIGS. 4 (F) and 4 (H) indicates the vehicle longitudinal direction. The amount of displacement (the amount of deviation) is shown.

  As shown in FIG. 4E, in the back door of the contrast structure (see the two-dot chain line), both end portions of the upper end of the back door are greatly warped, and the amount of curve change is large. On the other hand, in the back door 30 to which the vehicular back door structure according to the present embodiment is applied, as shown by the solid line in the graph, the amount of warping on both ends of the upper end of the back door is suppressed. The curve change amount is also small. The curve change amount is the maximum amount of distance from the straight line connecting both ends of the graph line to the point where the graph line intersects.

  Further, as shown in FIG. 4F, the displacement of the upper end portion of the back door in the vehicle front-rear direction is also more effective than the back door curve change amount of the comparison structure (see the two-dot chain line). The curve change amount of the back door (see solid line) to which the vehicular back door structure is applied is smaller. In addition, as shown in other graphs (FIGS. 4A to 4D, 4G, and 4H), the vehicle back door structure according to the present embodiment is applied. The back door (refer to the solid line) generally has a smaller amount of displacement than the back door of the contrast structure (refer to the two-dot chain line).

  Next, the graph of FIG. 5 will be described. FIG. 5 shows the relationship between the door hinge mounting position and the amount of curve change at the upper end of the back door. In other words, the horizontal axis represents the length of half of the upper side of the back door (30) as A, and the center position of the door hinge (22) in the vehicle width direction and the center position of the back door (30) in the vehicle width direction. When the distance in the vehicle width direction is B, (B / A) × 100 (%) is shown, and the vertical axis shows the curve change amount (mm) at the upper end of the back door. The target back door is obtained by changing the door hinge mounting position of the back door 30 in the present embodiment. As shown in FIG. 5, in the range of (B / A) × 100 ≧ 70 (that is, B ≧ 0.7A), the value of the curve change amount at the upper end of the back door is remarkably low. From this, in the range of B ≧ 0.7A, it is recognized that there is a remarkable effect in suppressing the amount of curve change at the upper end of the back door, and consequently suppressing the warpage of both ends of the upper end of the back door.

  As described above, according to the vehicle back door structure according to the present embodiment, it is possible to prevent or suppress the both end portions of the upper end portion of the back door from warping. In addition, it is not necessary to separately fix a metal reinforcement for suppressing warpage and surface distortion on the upper end portion of the door inner panel 34 (separately from the hinge reinforcement 46), so that weight reduction and cost reduction are achieved. be able to.

(Supplementary explanation of the embodiment)
In the above embodiment, the door inner panel 34 and the door outer panel 32A shown in FIG. 2 are made of resin, but these are made of metal (for example, made of aluminum alloy or thinned and weakened steel). It may be a panel other than a resin panel such as

  In the above embodiment, the first reinforcing bead 48C and the second reinforcing bead 50A are formed apart from each other in the vehicle width direction. For example, the first reinforcing bead (48C) is extended inward in the vehicle width direction. It is good also as a structure connected with the 2nd reinforcement bead (50A).

  Moreover, in the said embodiment, although the hinge reinforcement 46 is comprised including the 2nd reinforcement part 50 and such a structure is more preferable, it is set as the structure where a hinge reinforcement does not contain a 2nd reinforcement part (50). It is also possible.

  In addition, the said embodiment and the above-mentioned some modification can be implemented combining suitably.

10 Vehicle Rear 12 Back Door Opening 16 Rear Roof Header (Upper Body)
22 Door Hinge 30 Back Door 34 Door Inner Panel 36 Door Hinge Mounting Part 46 Hinge Reinforce 48 First Reinforcement Part 50 Second Reinforcement Part

Claims (2)

A back door capable of opening and closing a back door opening at the rear of the vehicle;
A pair of left and right door hinges provided at both ends of the upper end portion of the back door in the vehicle width direction and connecting the back door and the upper part of the vehicle body;
A terminal position provided on the back door, on the outer side in the vehicle width direction of the door hinge, is set to a position on the inner side in the vehicle width direction on the upper side of the back door, and 1 on the upper side of the back door. The relation of B ≧ 0.7A, where A / 2 is A, and B is the distance in the vehicle width direction between the center position in the vehicle width direction of the door hinge and the center position in the vehicle width direction on the upper side of the back door. At a position where is established, a door hinge mounting portion to which the door hinge is mounted,
A backdoor structure for a vehicle. Constituting an inner plate of the back door, a door inner panel provided with the door hinge mounting portion, and
A first reinforcing portion that is fixed to the door inner panel and reinforces the door hinge mounting portion of the door inner panel, and extends inward in the vehicle width direction from the first reinforcing portion and has a closed cross section with the door inner panel. A pair of left and right hinge reinforcements, comprising: a second reinforcing portion that forms and reinforces a portion in the vehicle width direction of the door hinge mounting portion in the door inner panel;
The vehicle back door structure according to claim 1, comprising: