Frontal collision energy absorption structure for vehicle

1. A frontal collision energy absorption structure for a vehicle, comprising:

a chassis frame,

wherein the chassis frame includes

a pair of right and left main frames extending in a vehicle length direction

a pair of suspension towers attached respectively to the main frames,

a front cross-member arranged apart from the suspension tower in front thereof and a rear cross-member arranged apart from the suspension tower in rear thereof, the front and rear cross-members each connecting the main frames together, and

a pair of engine mount brackets each attached to part of corresponding one of the main frames between the front and rear cross-members,

each of the engine mount brackets is attached to corresponding one of the main frames so as to be apart from a connection part of the corresponding one of the main frames and corresponding one of the suspension towers, a connection part of the corresponding one of the main frames and the front cross-member, and a connection part of the corresponding one of the main frames and the rear cross-member, and

at a position of each of the main frames overlapping with the rear cross-member in the vehicle length direction, a first weak part configured to facilitate deformation of the each of the main frames in the vehicle length direction upon a frontal collision of the vehicle is provided;

wherein a front leg part and a rear leg part branched to be separated from each other in the vehicle length direction are provided in a lower part of each of the suspension towers,

lower parts of the front and rear leg parts are attached to each of the main frames so as to be separated from each other in the vehicle length direction; and

a second weak part configured to facilitate deformation of each of the main frames in the vehicle length direction upon a frontal collision of the vehicle is provided at a position of the each of the main frames between the front and rear leg parts.

2. The frontal collision energy absorption structure of claim 1 , wherein

the second weak part is a recessed part formed in an upper part of each of the main frames.

3. The frontal collision energy absorption structure of claim 2 , wherein

the recessed part is formed at each corner in a vehicle width direction in the upper part of each of the main frames.

4. The frontal collision energy absorption structure of claim 1 , wherein

each of the engine mount brackets is arranged respectively between a corresponding one of the suspension towers and the rear cross-member in the vehicle length direction.

5. The frontal collision energy absorption structure of claim 1 , wherein

each of the engine mount brackets is, at an end thereof on a front side of the vehicle, downwardly inclined toward the front side of the vehicle such that a clearance is formed between the end of the each of the engine mount brackets and corresponding one of the suspension towers.

6. The frontal collision energy absorption structure of claim 1 , wherein

at a position of each of the main frames overlapping with corresponding one of the engine mount brackets in the vehicle length direction, a third weak part configured to facilitate deformation of the each of the main frames in the vehicle length direction upon a frontal collision of the vehicle is provided.

7. The frontal collision energy absorption structure of claim 1 , wherein

a weak part configured to facilitate deformation of each of the engine mount brackets in the vehicle length direction upon a frontal collision of the vehicle is provided in the each of the engine mount brackets.

8. A frontal collision energy absorption structure for a vehicle, comprising:

a chassis frame,

wherein the chassis frame includes

a pair of right and left main frames extending in a vehicle length direction,

a pair of suspension towers attached respectively to the main frames,

a front cross-member arranged apart from the suspension tower in front thereof and a rear cross-member arranged apart from the suspension tower in rear thereof, the front and rear cross-members each connecting the main frames together, and

a pair of engine mount brackets each attached to part of corresponding one of the main frames between the front and rear cross-members,

each of the engine mount brackets is attached to corresponding one of the main frames so as to be apart from a connection part of the corresponding one of the main frames and corresponding one of the suspension towers, a connection part of the corresponding one of the main frames and the front cross-member, and a connection part of the corresponding one of the main frames and the rear cross-member, and

at a position of each of the main frames overlapping with the rear cross-member in the vehicle length direction, a first weak part configured to facilitate deformation of the each of the main frames in the vehicle length direction upon a frontal collision of the vehicle is provided;

wherein each of the engine mount brackets includes an upper member and a lower member which are attached to an inner surface of a corresponding one of the main frames in a vehicle width direction and which protrude from the inner surface toward an inner side in the vehicle width direction,

the upper member is in a substantially inverted U-shape as viewed in a cross section along the vehicle length direction,

the lower member is in a substantially U-shape as viewed in the cross section along the vehicle length direction,

side end parts of the upper member in the vehicle length direction are joined respectively to side end parts of the lower member in the vehicle length direction,

an engine mount is attached to an upper surface of the upper member,

a notch opening on the inner side in the vehicle width direction is formed in a bottom part of the lower member, and

an elongated hole extending in the vehicle length direction is formed at a position overlapping each of the engine mount brackets in the vehicle length direction in the inner surface of each of the main frames in the vehicle width direction.

9. A frontal collision energy absorption structure for a vehicle, comprising:

a pair of main frames extending in a vehicle length direction;

a front cross-member and a rear cross-member connecting the main frames together and respectively supporting front and rear parts of a front wheel suspension device of the vehicle; and

a suspension tower and an engine mount bracket which are attached to each of the main frames,

wherein the front and rear cross-members, the suspension tower, and the engine mount bracket are apart from each other on each of the main frames, and

at a position of each of the main frames overlapping with the rear cross-member in the vehicle length direction, a first weak part configured to facilitate deformation of the each of the main frames in the vehicle length direction upon a frontal collision of the vehicle is provided;

wherein the suspension tower is branched into a front leg part and a rear leg part in a lower part of the suspension tower,

the front and rear leg parts are separated from each other in the vehicle length direction, and are attached to each of the main frames so as to be separated from each other in the vehicle length direction; and

a second weak part is provided at a position of each of the main frames between the front and rear leg parts.

10. The frontal collision energy absorption structure of claim 9 , wherein

the second weak part is a recessed part formed in each of the main frames.

11. The frontal collision energy absorption structure of claim 10 , wherein

the recessed part is formed at a corner in an upper part of each of the main frames.

12. The frontal collision energy absorption structure of claim 9 , wherein

the engine mount bracket is arranged between the suspension tower and the rear cross-member in the vehicle length direction.

13. The frontal collision energy absorption structure of claim 12 , wherein

the engine mount bracket is, at an end thereof on a front side of the vehicle, downwardly inclined toward the front side of the vehicle such that a clearance is formed between the end of the engine mount bracket and the suspension tower.

14. The frontal collision energy absorption structure of claim 9 , wherein

the engine mount bracket includes an upper member and a lower member which are attached to an inner surface of each of the main frames in a vehicle width direction and which protrude from the inner surface toward an inner side in the vehicle width direction,

the upper member is in a substantially inverted U-shape as viewed in a cross section along the vehicle length direction,

the lower member is in a substantially U-shape as viewed in the cross section along the vehicle length direction,

the upper and lower members are joined to each other,

an engine mount is attached to an upper surface of the upper member,

a notch is formed in the lower member, and

an elongated hole is formed at a position overlapping the engine mount bracket in the vehicle length direction in the inner surface of each of the main frames in the vehicle width direction.

15. The frontal collision energy absorption structure of claim 9 , wherein

a third weak part is provided at a position of each of the main frames overlapping with the engine mount bracket in the vehicle length direction.