| 摘要 |
PROBLEM TO BE SOLVED: To provide a method of manufacturing a member having a closed cross section made of metal by which the member having the closed cross section made of the metal is manufactured accurately by comparatively simple method.SOLUTION: The method of manufacturing the member having the closed cross section made of metal, by which the member having the closed cross section which is formed into a closed cross section shape from a planar workpiece made of the metal is manufactured, includes a first press-forming stage where the planar workpiece W11 is press-formed into a projecting shape by using a first press forming die and a second press-forming stage where, by using a second forming die 150 after the first press-forming stage and, by performing the press forming by moving the core die relatively to the die, in the state where the press-formed planar workpiece W11 is arranged between the die 155 of the second forming die and the core die 151 of the second forming die, the projecting side face parts W13, W14 on both sides of the projecting top surface part W12 which is the planar workpiece formed in the first press-forming stage formed into the projecting shape are displaced on the inward side of the planar workpiece respectively and made into the closed cross section. |
