Reinforced structure of vehicle for absorbing side collision

1 . A side lower structure of a vehicle, the side lower structure comprising:

a seat cross member disposed in a width direction of the vehicle and assembled to a floor panel of the vehicle;

a seat cross member extension assembled to the seat cross member for connecting a side sill inner with the seat cross member; and

inclined ribs formed on the seat cross member extension in the width direction of the vehicle, the inclined ribs being spaced by a predetermined distance from each other in a longitudinal direction of the vehicle,

wherein the inclined ribs include:

first inclined ribs configured to transmit a collision load input to the side sill inner to side and upper surfaces of the seat cross member and disposed to be spaced in the longitudinal direction of the vehicle on the seat cross member extension; and

second inclined ribs configured to transmit the collision load input to the side sill inner to the upper surface of the seat cross member and formed between the first inclined ribs spaced apart from each other.

2 . The side lower structure of claim 1 , wherein the inclined ribs have a smaller height toward an inside of the vehicle.

3 . The side lower structure of claim 1 , wherein the seat cross member is formed with one or more reinforcement ribs connecting upper and lower surfaces of the seat cross member inside the seat cross member.

4 . The side lower structure of claim 3 , wherein the inclined ribs are aligned with the reinforcement ribs positioned on a virtual plane.

5 . The side lower structure of claim 1 , wherein the seat cross member extension includes:

a body in contact with an upper surface of the seat cross member;

an upper flange portion coupled to an upper surface of the side sill inner;

a vertical flange portion extending downward from the upper flange portion and coupled to a side surface of the side sill inner; and

a lower flange portion extending from a lower end of the vertical flange portion in a direction parallel to the floor panel and coupled to the floor panel,

wherein a first inclined rib extends downward from the upper flange portion and is formed to be in contact with the side surface of the seat cross member and connected to the lower flange portion, and

wherein a second inclined rib extends downward from the upper flange portion and is formed to be connected to the body.

6 . The side lower structure of claim 5 , wherein an auxiliary rib is formed on the body in the longitudinal direction of the vehicle to intersect the first inclined rib and the second inclined rib, or wherein an inner end of the body facing the inside of the vehicle is formed with a curved portion to be rounded to an outside of the vehicle.

7 . The side lower structure of claim 6 , wherein the curved portion is formed on an end of the inclined rib at a predetermined distance.

8 . The side lower structure of claim 1 , wherein the inclined ribs are disposed on frontmost and rearmost portions in the longitudinal direction of the vehicle, the inclined ribs being aligned with reinforcement ribs on a same virtual plane, and other inclined ribs are alternately aligned with the reinforcement ribs.

9 . The side lower structure of claim 1 , wherein the seat cross member extension is manufactured by die casting, and the seat cross member is manufactured by extrusion.

10 . The side lower structure of claim 1 , wherein the seat cross member extension is coupled to each of the upper and side surfaces of the side sill inner, coupled to each of the upper and side surfaces of the seat cross member, and coupled to the upper surface of the floor panel.

11 . The side lower structure of claim 10 , wherein the seat cross member extension is coupled to the upper and side surfaces of the side sill inner by a screw or a fastening bolt.

12 . The side lower structure of claim 10 , wherein the seat cross member extension is fastened to the upper and side surfaces of the seat cross member by a screw, or the seat cross member extension is coupled to the upper surface of the floor panel by a rivet.

13 . The side lower structure of claim 12 , wherein an inner end of the seat cross member extension facing the inside of the vehicle is coupled to the upper surface of the seat cross member by welding.

14 . The side lower structure of claim 1 , wherein the vehicle is an electric vehicle in which a battery is mounted on a lower surface of the floor panel.

15 . A vehicle comprising the side lower structure of claim 1 .

16 . A vehicle comprising:

a floor panel mounted with a battery;

a side sill coupled to a side surface of the floor panel;

a seat cross member disposed in a width direction of the vehicle and assembled to the floor panel;

a seat cross member extension assembled to the seat cross member and connecting a side sill inner with the seat cross member to support a side collision load; and

inclined ribs formed on the seat cross member extension in the width direction of the vehicle, and spaced by a predetermined distance from each other in a longitudinal direction of the vehicle,

wherein the inclined ribs include:

first inclined ribs configured to transmit a collision load input to the side sill inner to side and upper surfaces of the seat cross member and disposed to be spaced in the longitudinal direction of the vehicle on the seat cross member extension; and

second inclined ribs configured to transmit the collision load input to the side sill inner to the upper surface of the seat cross member and formed between the first inclined ribs spaced apart from each other.

17 . The vehicle of claim 16 , wherein the seat cross member extension includes:

a body in contact with the upper surface of the seat cross member;

an upper flange portion coupled to an upper surface of the side sill inner;

a vertical flange portion extending downward from the upper flange portion and coupled to a side surface of the side sill inner; and

a lower flange portion extending from a lower end of the vertical flange portion in a direction parallel to the floor panel and coupled to the floor panel,

wherein the first inclined rib extends downward from the upper flange portion and is formed to be in contact with the side surface of the seat cross member and connected to the lower flange portion, and

the second inclined rib extends downward from the upper flange portion and is formed to be connected to the body.