WORKING ARM STRUCTURE OF WORKING MACHINE

摘要

PROBLEM TO BE SOLVED: To provide a working arm structure of a working machine which can appropriately weld internal members erected on and joined with the inner side of a box-shaped section of the working arm formed in a box-shaped section by plate members from the outer side of the box-shaped section, weld the plate members forming a box-shaped structure at one time in a manufacturing process of the working arm, and give the sufficient strength to the working arm. SOLUTION: A wide part wider than the thickness of an internal member is formed in a part to which the plate-like internal member is welded.