Patent ID: 7338080

Claim:
A truck frame for a construction machine, said truck frame including a center frame for supporting an upper structure, right and left side frames extending toward and between fore and rear ends of right and left sides of said center frame, respectively, right and left fore legs provided on the right and left sides of said center frame, respectively, to connect said right and left side frames to right and left sides of said center frame, respectively, and right and left hind legs provided on said right and left sides of said center frame, respectively, to connect said right and left side frames to said right and left sides of said center frame, respectively, characterized in that: each of said fore and hind legs is constituted by an inner joint portion joined with said center frame by welding, an outer joint portion joined with a respective one of said side frames by welding, and an intermediate tubular portion provided between said inner and outer joint portions; each of said inner joint portions and each of said outer joint portions is constituted by a flare tube gradually increasing in diameter from said intermediate tubular portion toward a joining end portion thereof; said joining end portions of each of said inner joint portions and each of said outer joint portions being an open end of a substantially rectangular shape; and said flare tube is formed by casting using molten iron-base metal.