Vehicle intermediate structure

1. A vehicle intermediate structure comprising:

a first intermediate crossmember connecting a pair of side sills in a width direction of a vehicle;

wherein each end face of the first intermediate crossmember is attached to an inboard side surface of a corresponding side sill; and

wherein a cross section of the first intermediate crossmember is uniform in a longitudinal direction thereof;

wherein the first intermediate crossmember is supported with respect to the pair of side sills through a pair of support brackets, respectively; and

wherein the support bracket includes a first fixed surface that is fixed to the inboard side surface of the corresponding side sill, a second fixed surface that is fixed to a bottom surface of the first intermediate crossmember, and an inclined surface extending obliquely between a bottom end of the first fixed surface and an inboard-side end of the second fixed surface.

2. The vehicle intermediate structure according to claim 1 , wherein:

the first intermediate crossmember supports a pair of rear side members through a mechanical joint system; and

each rear side member is connected to a rear portion of the corresponding side sill.

3. The vehicle intermediate structure according to claim 2 , wherein a front end face of the rear side member is fixed to a rear surface of the first intermediate crossmember adjacent to each end portion of the first intermediate crossmember.

4. The vehicle intermediate structure according to claim 3 , wherein:

the rear side member has an opening provided in a front portion thereof; and

the end portion of the first intermediate crossmember is fitted into the opening of the corresponding rear side member.

5. The vehicle intermediate structure according to claim 4 , wherein:

the rear side member includes a top retention portion extending from a top end of the front end face to the first intermediate crossmember;

the top retention portion is fixed to a top surface of the first intermediate crossmember; and

the opening has an L-shaped cross section defined by the top retention portion and the front end face.

6. The vehicle intermediate structure according to claim 4 , wherein:

the rear side member includes a top retention portion extending from a top end of the front end face to the first intermediate crossmember and a bottom retention portion extending from a bottom end of the front end face to the first intermediate crossmember;

the top retention portion is fixed to a top surface of the first intermediate crossmember;

the bottom retention portion is fixed to the bottom surface of the first intermediate crossmember; and

the opening has a U-shaped cross section defined by the top retention portion, the front end face, and the bottom retention portion.

7. The vehicle intermediate structure according to claim 6 , wherein:

the top retention portion has a top recess which is recessed from a top surface of the top retention portion toward the first intermediate crossmember; and

the bottom retention portion has a bottom recess which is recessed from a bottom surface of the bottom retention portion toward the first intermediate crossmember.

8. The vehicle intermediate structure according to claim 1 , wherein:

the first intermediate crossmember further includes a retention portion extending from a top end of each end face thereof to the corresponding side sill; and

the retention portion is fixed to a top surface of the corresponding side sill.

9. The vehicle intermediate structure according to claim 1 , wherein:

the first intermediate crossmember has a closed cross section; and

the first intermediate crossmember comprises a high-tensile strength steel plate.

10. A vehicle intermediate structure comprising:

a first intermediate crossmember connecting a pair of side sills in a width direction of a vehicle; and

a second intermediate crossmember connected to the first intermediate crossmember, the second intermediate crossmember comprising a center portion extending in the width direction of the vehicle and a pair of bent portions provided on both ends of the center portion;

wherein each end face of the first intermediate crossmember is attached to an inboard side surface of the corresponding side sill;

wherein a cross section of the first intermediate crossmember is uniform in a longitudinal direction thereof;

wherein each bent portion of the second intermediate crossmember is fixed to each end portion of the first intermediate crossmember and a corresponding rear side member;

wherein the first intermediate crossmember is supported with respect to the pair of side sills through a pair of support brackets, respectively; and

wherein each support bracket includes a first fixed surface that is fixed to the inboard side surface of the corresponding side sill, a second fixed surface that is fixed to a bottom surface of the first intermediate crossmember, and an inclined surface extending obliquely between a bottom end of the first fixed surface and an inboard-side end of the second fixed surface.

11. The vehicle intermediate structure according to claim 10 , wherein:

a front surface of each bent portion is fixed to the end portion of the corresponding first intermediate crossmember; and

an outboard side surface of the bent portion is fixed to an inboard side surface of the corresponding rear side member.

12. The vehicle intermediate structure according to claim 10 , wherein:

the center portion is located higher than the first intermediate crossmember; and

the bent portion is bent from each end of the center portion toward the first intermediate crossmember.

13. The vehicle intermediate structure according to claim 10 , wherein:

a longitudinal axis of the center portion is parallel to a longitudinal axis of the first intermediate crossmember; and

a longitudinal axis of the bent portion is perpendicular to the longitudinal axis of the center portion.

14. The vehicle intermediate structure according to claim 10 , wherein:

a cross section of the center portion of the second intermediate crossmember is uniform in a longitudinal direction thereof; and

a cross section of the bent portion of the second intermediate crossmember is uniform in a longitudinal direction thereof.

15. The vehicle intermediate structure according to claim 10 , wherein the cross section of the center portion is the same as the cross section of the bent portion.

16. The vehicle intermediate structure according to claim 10 , wherein the second intermediate crossmember comprises a mass-produced steel pipe having a closed cross section.

17. A vehicle frame comprising:

a center frame module comprising a pair of side sills disposed on both side edges thereof;

a front structure connected to a front of the center frame module;

a rear frame module connected to a rear of the center frame module; and

an intermediate structure disposed between the center frame module and the rear frame module, the intermediate structure comprising a first intermediate crossmember connecting the pair of side sills in a width direction of the vehicle frame;

wherein each end face of the first intermediate crossmember is attached to an inboard side surface of the corresponding side sill;

wherein a cross section of the first intermediate crossmember is uniform in a longitudinal direction thereof;

wherein the first intermediate crossmember is supported with respect to the pair of side sills through a pair of support brackets, respectively; and

wherein the support bracket includes a first fixed surface that is fixed to the inboard side surface of the corresponding side sill, a second fixed surface that is fixed to a bottom surface of the first intermediate crossmember, and an inclined surface extending obliquely between a bottom end of the first fixed surface and an inboard-side end of the second fixed surface.

18. The vehicle frame according to claim 17 , wherein:

the first intermediate crossmember supports a pair of rear side members through a mechanical joint system; and

each rear side member is connected to a rear portion of the corresponding side sill.

19. The vehicle frame according to claim 18 , wherein a front end face of the rear side member is fixed to a rear surface of the first intermediate crossmember adjacent to each end portion of the first intermediate crossmember.

20. The vehicle frame according to claim 19 , wherein:

the rear side member has an opening provided in a front portion thereof;

the end portion of the first intermediate crossmember is fitted into the opening of the corresponding rear side member;

the rear side member includes a top retention portion extending from a top end of the front end face to the first intermediate crossmember and a bottom retention portion extending from a bottom end of the front end face to the first intermediate crossmember;

the top retention portion is fixed to a top surface of the first intermediate crossmember;

the bottom retention portion is fixed to the bottom surface of the first intermediate crossmember; and

the opening has a U-shaped cross section defined by the top retention portion, the front end face, and the bottom retention portion.