Patent ID: 7997619

Claim:
A track frame comprising a center frame mounting a swiveling body so that the swiveling body can swivel about a swivel axis, a pair of right and left side frames arranged laterally of the center frame, and a pair of front and rear, right and left connecting legs jointed to said center frame and said side frames for connecting these together; wherein each said connecting leg includes a tubular body portion having a pair of opened edges, a center joining portion provided at one of the opened edges of the body portion to be joined to the center frame and a side joining portion provided at the other opened edge of the body portion to be joined to the side frame; and wherein in the center joining portion of the connecting leg, one of its upper and lower ends is formed as an overlapping portion to be overlapped vertically with the center frame, the other is formed as an abutment portion in horizontal abutment to the center frame, and said overlapping portion and said abutment portion are joined to the center frame by welding, and a portion between the overlapping portion and the abutment portion is formed as a contacting portion opposed to the lateral side of the center frame and vertically extending.