Vehicle rear portion structure

1 . A vehicle rear portion structure comprising:

a pair of rear portion structural members spaced apart in a vehicle width direction;

a pair of rear side members spaced apart in the vehicle width direction; and

a cross-connection member connecting the rear portion structural members to each other, wherein:

each of the rear portion structural members is a hollow member in which a body portion, a tower portion, and a suspension member portion are integrally cast;

the body portion includes a front end connected to a rear pillar and a rear end connected to a rear side member of the rear side members;

the tower portion includes a tower shape with a downward opening so as to receive a part of a suspension device, and stands upward from the body portion;

the suspension member portion includes a front end connected to a rocker and extends downwardly from the body portion to support the suspension device;

the rear side member and the cross-connection member are tubular extruded members; and

the cross-connection member includes a connecting portion extending in the vehicle width direction in a portion of a vehicle that is rearward of the rear portion structural member, and a pair of arm portions extending forward in a vehicle front-rear direction from both ends of the connecting portion in the vehicle width direction and connected to the tower portions, the cross-connection member being substantially U-shaped and projecting rearward in the vehicle front-rear direction in a plan view.

2 . The vehicle rear portion structure according to claim 1 , further comprising a first cross member connecting vicinities of lower ends of the tower portions of the rear portion structural members in the vehicle width direction, wherein in a plan view, a first annular shape projecting rearward in the vehicle front-rear direction is made by the first cross member, the tower portions, and the cross-connection member.

3 . The vehicle rear portion structure according to claim 2 , wherein:

an access opening of a luggage space and a rear door that opens and closes the access opening are further provided;

the access opening extends substantially horizontally at a position approximately at the same height as the cross-connection member;

the cross-connection member surrounds a part of a periphery of the access opening; and

the rear door is disposed above the cross-connection member.

4 . The vehicle rear portion structure according to claim 1 , further comprising a pair of connecting members connected to the pair of rear portion structural members, wherein each of the connecting members joins a front upper corner of the body portion and an upper portion of the tower portion.

5 . The vehicle rear portion structure according to claim 4 , further comprising a second cross member connecting front ends of the rear portion structural members to each other in the vehicle width direction, wherein:

each of the connecting members extends obliquely rearward and upward from the front upper corner of the body portion, and then curves to extend rearward in the vehicle front-rear direction;

a rear end of the connecting member is positioned on an extension line extended forward in the vehicle front-rear direction from an arm portion of the arm portions; and

a second annular shape projecting rearward in the vehicle front-rear direction in a plan view is made by the second cross member, the connecting members, and the cross-connection member.