Vehicle support structure and method of manufacturing same

1. A vehicle support structure formed by casting, the vehicle support structure comprising:

a main body part;

a plurality of support portions extending from the main body part to support vehicle components, and

a plurality of rib portions configured to connect the support portions and the main body part, respectively,

wherein a casted lightening portion is located at least in one of the rib portions, and

wherein an external component mounting portion is formed in the casted lightening portion, and a portion of a sidewall of the casted lightening portion has an opening that is continuous with a portion of a sidewall of the external component mounting portion.

2. The vehicle support structure according to claim 1 , wherein the vehicle support structure is made of aluminum or aluminum alloy.

3. The vehicle support structure according to claim 2 , wherein the one rib portion in which the casted lightening portion is formed connects the largest one of the support portions and the main body part.

4. The vehicle support structure according to claim 1 , wherein the one rib portion in which the casted lightening portion is formed connects the largest one of the support portions and the main body part.

5. The vehicle support structure according to claim 1 , wherein the external component mounting portion comprises a machined surface and a surface of the casted lightening portion comprises a casted surface, different from the machined surface.

6. The vehicle support structure according to claim 5 , wherein the external component mounting portion is in a different orientation than mounting holes in at least one of the plurality of support portions.

7. The vehicle support structure according to claim 6 , wherein the external component mounting portion is in a different orientation than mounting holes in two of the plurality of support portions.

8. The vehicle support structure according to claim 6 , wherein the external component mounting portion is in a same orientation as a mounting hole in another of the plurality of support portions.

9. The vehicle support structure according to claim 6 , wherein the external component mounting portion and the surface of the casted lightening portion both extend to an edge of one of the plurality of rib portions that connects the one of the plurality of support portions and the main body part.

10. The vehicle support structure according to claim 6 , wherein the external component mounting portion forms a stepped portion at the edge of the surface in the casted lightening portion.

11. The vehicle support structure according to claim 6 , wherein the vehicle support structure is a steering knuckle.

12. The vehicle support structure according to claim 6 , wherein the plurality of support portions comprise four support portions each of which extend from a side portion of the main body.

13. The vehicle support structure according to claim 12 , wherein the plurality of rib portions comprise four rib portions which connect the four support portions to the main body.

14. The vehicle support structure according to claim 13 , wherein the plurality of support portions comprise two caliper mounting portions and a lateral link mounting portion on a rear side of the main body.

15. The vehicle support structure according to claim 14 , wherein the lightening portion is formed in a rib portion connecting the one of the support portions and the main body part.

16. The vehicle support structure according to claim 15 , wherein the one of the support portions has a width larger than remaining support portions.

17. The vehicle support structure according to claim 5 , further comprising an opening in the external component mounting portion, remote from the edge of the surface in the casted lightening portion.