Patent ID: 8070216

Claim:
A frame for a vehicle comprising a plurality of closed-perimeter hollow tubular members welded together and defining at least substantially vertical sides walls of the frame; an opening defined in at least one of the side walls of the frame for receiving at least one of a door and a window of the vehicle therein, the opening being bordered by at least two of said hollow tubular members disposed substantially perpendicularly to each other with first remote ends thereof being spaced apart from one another on either side of a corner region of the opening, said at least two hollow tubular members defining a substantially vertical plane within which they lie; a non-tubular reinforcing corner member interconnecting the first remote ends of said two hollow tubular members such that only the non-tubular reinforcing corner member is disposed between said first remote ends of the two hollow tubular members within said corner region, the non-tubular reinforcing corner member having perpendicularly oriented ends which are abutted end-to-end with respective ones of the first remote ends of said at least two of said hollow tubular members, said reinforcing corner member including a pair of solid plates disposed parallel to each other and being spaced apart by at least one cross-member disposed between said plates and oriented perpendicularly thereto, said plates being substantially parallel to the plane defined by the hollow tubular members, each plate of the reinforcing corner member having integral first and second elongated portions thereof disposed on either side of a continuous curve therebetween, the curve in said plate having a substantially constant radius of curvature such as to define a smooth transition between the integral first and second elongated portions of the plate; wherein the reinforcing corner member distributes stress away from the curved corner and to the tubular members, such as to prevent stress concentration at a joint between the at least two tubular members surrounding said opening in the frame.