Vehicle floor structure

A vehicle floor structure, comprising:

• a floor panel integrally including a raised tunnel portion extending along the longitudinal direction of a vehicle;
• and
• a floor cross member extending along the lateral direction of the vehicle so as to traverse the tunnel portion, and being joined at both ends to left and right rockers extending along the left and right edges of the floor panel, and further joined to an upper surface of the floor panel, wherein
• the floor cross member comprises both a cross member center component and left and right cross member side components, the cross member center component is placed along an outer surface of the tunnel portion on the upper surface of the floor panel, at a first location along the longitudinal direction, so as to extend across the tunnel portion, and is made of an aluminum alloy cast with a recess formed in an undersurface of the cross member center component to accommodate the tunnel portion,
• each of the left and right cross member side components is made of a steel plate and is joined to a corresponding one of left and right ends of the cross member center component at a position located outside the tunnel portion in the lateral direction of the vehicle, and at the first location in the longitudinal direction,
• the cross member center component comprises a base plate disposed at the same height as an upper plate of each of the left and right cross member side components, each of the upper plates extending straight along the lateral direction of the vehicle, with an end of each of the upper plates abutting against a corresponding one of contact surfaces disposed at both lateral ends of the base plate, and
• the cross member center component comprises, on an upper surface thereof, a plurality of upper ribs extending so as to intersect the longitudinal direction of the vehicle.

A vehicle floor structure, comprising:

• a floor panel integrally including a raised tunnel portion extending along the longitudinal direction of a vehicle;
• and
• a floor cross member extending along the lateral direction of the vehicle so as to traverse the tunnel portion, and being joined at both ends to left and right rockers extending along the left and right edges of the floor panel, and further joined to an upper surface of the floor panel, wherein
• the floor cross member comprises both a cross member center component and left and right cross member side components, the cross member center component is placed along an outer surface of the tunnel portion on the upper surface of the floor panel so as to extend across the tunnel portion, and is made of an aluminum alloy cast with a recess formed in an undersurface of the cross member center component to accommodate the tunnel portion,
• each of the left and right cross member side components, is made of a steel plate and is joined to a corresponding one of left and right ends of the cross member center component at a position located outside the tunnel portion in the lateral direction of the vehicle,
• the cross member center component comprises a base plate disposed at the same height as an upper plate of each of the left and right cross member side components, each of the upper plates extending straight along the lateral direction of the vehicle, with an end of each of the upper plates abutting against a corresponding one of contact surfaces disposed at both lateral ends of the base plate,
• the cross member center component comprises an overlapping portion extending from the contact surface toward a lateral outside of the vehicle, the overlapping portion designed to be overlaid on a part of the cross member side component, and
• in the overlapping portion, the cross member center component and the cross member side component are fastened along with a leg of a seat in the vehicle by a common bolt.