Door assembly for vehicle

1. A vehicle door assembly including a vehicle door for opening and closing a door opening of a vehicle body,

the vehicle door comprising:

a door body of a hollow shape including an outer door panel and an inner door panel;

an exterior member formed of a softer material than the door body and mounted on an outer surface of the outer door panel to cover at least a part of the outer surface of the outer door panel; and

a seal member capable of contacting and sealing a frame section defining the door opening, when the door is closed,

the exterior member comprising;

an exterior member body covering an outer surface of the outer door panel;

an extension section extending from the exterior member body outwardly beyond an edge of the door body along the outer surface of the outer door panel; and

a closed section part formed in a closed section shape on a reverse surface of the extension section, the seal member being mounted on the closed section part, the closed section part being structurally independent from the seal member and being formed solely by the exterior member.

2. The vehicle door assembly according to claim 1 , wherein the frame section has a door-facing surface capable of facing the edge of the door body when the door is closed, and

the closed section part is disposed to be positioned between the edge of the door body and the door-facing surface when the door is closed.

3. The vehicle door assembly according to claim 2 , wherein the frame section has a sealing surface extending from the door-facing surface toward the door opening, and

the seal member is disposed to contact the sealing surface as the door is closed in a direction substantially perpendicular to the door opening.

4. The vehicle door assembly according to claim 3 , wherein at least a part of an inner peripheral surface of the frame section comprises a slanting wall section inclined from an end of the sealing surface closer to the door opening toward a center of the door opening and toward an interior of the vehicle, and

wherein, when the door is closed, the end of the sealing surface is located closer to the door-facing surface than a start point where an edge of the outer door panel and an edge of the inner door panel start being superposed on each other.

5. The vehicle door assembly according to claim 3 , wherein at least a part of the outer peripheral surface of the frame section comprises a design wall section formed continuously with the door-facing surface, and

an outer surface of the design wall section is shaped such that it lies substantially flush with an outer surface of the exterior member when the door is closed.

6. The vehicle door assembly according to claim 1 , wherein the closed section part has an end surface extending adjacent to an opposite side of the edge of the door body from the reverse surface of the extension section, and

the seal member is mounted on the end surface of the closed section part.

7. The vehicle door assembly according to claim 1 , wherein the seal member is fixed to the closed section part by means of a seal fixing member, the seal fixing member is engaged by the closed section part by being partly inserted in an interior of the closed section part.

8. The vehicle door assembly according to claim 1 , wherein the closed section part includes: a substantially horizontal lower plate portion disposed beneath the edge of the door body; a joining flange section extending upward from the lower plate portion and joined to a reverse surface of the exterior member body; and at least one rib formed on a corner between the lower plate portion and the joining flange section, and

the seal member includes: a seal section capable of contacting and sealing the frame section; a projecting section extending from the seal section, along an upper surface of the lower plate portion, to the rib; and an outer-surface sealing section extending upward from a distal end of the projecting section,

wherein the outer-surface sealing section is sandwiched by the outer surface of the outer door panel and the rib near a lower edge of the door body.

9. The vehicle door assembly according to claim 1 , wherein the vehicle door is a door disposed to extend substantially vertically when the vehicle door is in a closed position,

the door body has at least one drainage hole formed therein for discharging water having entered an interior of the door body,

the drainage hole is located closer to the frame section than the lower edge of the door body when the door is closed,

the seal member includes a slant section slanting in a thickness direction of the door body, and a drainage sealing section connecting integrally to the slant section,

the slant section is located closer to the frame section than the drainage hole and opposed to the drainage hole and slants downward toward the extension section when the door is closed,

the drainage sealing section extends from a lower end of the slant section in a direction toward the door body and extends beneath the drainage hole to the lower edge of the door body, and

the exterior member includes a seal backup portion having a flat upper surface for supporting thereon a reverse surface of the drainage sealing section.

10. The vehicle door assembly according to claim 9 , wherein the seal backup portion includes a wall section extending downward from an end, located remote from the door body, of the seal backup portion, a surface of the wall section opposite from the reverse surface of the extension section being provided as a seal mounting surface,

the seal member includes a seal mounting section shaped to extend along the seal mounting surface, and

the seal mounting section is superposed on and mounted on the seal mounting surface.

11. A vehicle door assembly including a vehicle door for opening and closing a door opening of a vehicle body,

the vehicle door comprising: a door body; and a resin-made exterior member covering an outer surface of the door body,

the exterior member comprising:

an exterior member body covering the outer surface of the door body;

a flange section extending from an edge of the exterior member body toward a peripheral edge section of the door body;

a bent section formed integrally with a distal end of the flange section and bendable in a thickness direction of the flange section;

an inner wall formed integrally with the bent section and bendable about the bent section toward a reverse surface of the exterior member body; and

a joining flange section formed at a distal end of the inner wall and capable of being joined to the reverse surface of the exterior member body,

wherein the bent section extends straight along the distal end of the flange section,

the exterior member body and the flange section together constitute a first closed section part of a closed sectional shape when the joining flange section is joined to the reverse surface of the exterior member body,

a spaced-apart distance from the edge of the exterior member body to the bent section differs among portions of the exterior member body,

the bent section and the inner wall are provided only in portions of the exterior member body where the spaced-apart distance is greater than a predetermined distance,

an inner wall member separate from the inner wall is mounted on the reverse surface of a remaining portion where the bent section and the inner wall are not provided, and

the inner wall member and the exterior member body together constitute a second closed section part of a closed sectional shape continuous with the first closed section part.

12. The vehicle door assembly according to claim 11 , wherein the inner wall member includes a superposition section superposed on the inner wall of the exterior member, and the superposition section is joined to the inner wall.

13. The vehicle door assembly according to claim 12 , wherein the joining flange section is joined to the reverse surface of the exterior member body by adhesive bonding, and

the superposition section is joined to the inner wall of the exterior member by a mechanical joint.

14. The vehicle door assembly according to claim 12 , wherein the superposition section is a section located in an interior of the first closed section part and superposed on the inner wall.

15. The vehicle door assembly according to claim 12 , wherein the exterior member further includes a separate-member joining mechanism for joining the inner wall member to the exterior member body, and

the separate-member joining mechanism is located near the superposition section.

16. The vehicle door assembly according to claim 15 , wherein the separate-member joining mechanism includes:

a locking claw projecting from the flange section toward the inner wall member;

a locking surface that is one surface of the locking claw and that faces the reverse surface of the exterior member body; and

an engagement section formed on the inner wall member for locking engagement by the locking surface, and

wherein the inner wall member is joined to the exterior member body by being sandwiched between the reverse surface of the exterior member body and the locking surface.

17. The vehicle door assembly according to claim 16 , wherein the engagement section is formed in a shape recessed from a surface, abutting against the locking surface, of the inner wall member toward the reverse surface of the exterior member body.

18. The vehicle door assembly according to claim 11 , wherein the exterior member further includes an end wall section extending from at least one end, in an extending direction of the bent section extending straight, of the exterior member body toward the door body, and

an opening, located near the one end of the exterior member body, of the first closed section part is covered with the end wall section.

19. The vehicle door assembly according to claim 11 , wherein the exterior member further includes a body end joint section that joins the exterior member body to the door body, and

the joining flange section includes an evacuation section formed in such a manner as to bypass the body end joint section, without interfering with the body end joint section, when the joining flange section is joined to the exterior member body.

20. The vehicle door assembly according to claim 19 , wherein the exterior member further includes a shield wall closing up a gap between the reverse surface of the exterior member body and the evacuation section.

21. A vehicle door assembly including a vehicle door for opening and closing a get-in/out opening of a vehicle body,

the vehicle door comprising:

a door body of a hollow sectional shape;

an exterior member mounted on a lower section of an outer surface of the outer door body and including an extension section extending downward beyond a lower edge of the door body; and

a seal member mounted on the extension section and capable of contacting and sealing a frame section, defining the get-in/out opening, when the door is closed,

wherein the door body has at least one drainage hole for discharging water having entered an interior of the door body,

the seal member includes a slant section located closer to the frame section than the drainage hole when the door is closed, and

the slant section is opposed to the drainage hole and slants downward toward the extension section.

22. The vehicle door assembly according to claim 21 , wherein the drainage hole is located closer to the frame section than the lower edge of the door body when the door is closed,

the seal member includes a drainage sealing section connecting integrally to the slant section, and

the drainage sealing section extends from a lower end of the slant section in a direction toward the door body and extends beneath the drainage hole to the lower edge of the door body.

23. The vehicle door assembly according to claim 22 , wherein the seal member includes an outer-surface sealing section extending upward from a distal end of the drainage sealing section, and,

the outer-surface sealing section is sandwiched between the outer surface of the outer door panel and the exterior member near the lower edge of the door body.

24. The vehicle door assembly according to claim 22 , wherein the exterior member includes a seal backup portion having a flat upper surface for supporting thereon a reverse surface of the drainage sealing section.

25. The vehicle door assembly according to claim 24 , wherein the seal backup portion includes a wall section extending downward from an end, located remote from the door body, of the seal backup portion, a surface of the wall section opposite from the reverse surface of the extension section being provided as a seal mounting surface,

the seal member includes a seal mounting section shaped to extend along the seal mounting surface, and

the seal mounting section is superposed on and mounted on the seal mounting surface.

26. The vehicle door assembly according to claim 25 , wherein the seal mounting section has an upper end formed integrally with a base portion of the drainage sealing section merging with the lower end of the slant section.

27. The vehicle door assembly according to claim 26 , wherein, of the seal member, a seal section for contacting and sealing the frame section is a hollow seal section having a hollow sectional shape, and

the hollow seal section is formed integrally to integrally include the slant section, the seal mounting section and a lower half section extending from a lower end of the seal mounting section to an upper end of the slant section.

28. The vehicle door assembly according to claim 24 , wherein the exterior member includes:

a joining flange section extending upward from an end, adjacent to a reverse surface of the exterior member, of the seal backup portion and joined to the reverse surface of the exterior member; and

at least one rib formed on a corner between the seal backup portion and the joining flange section, and

wherein the seal member includes an outer-surface sealing section extending upward from a distal end of the drainage sealing section, and

the outer-surface sealing section is sandwiched by the outer surface of the door body and the rib near the lower edge of the door body.