| 摘要 |
PROBLEM TO BE SOLVED: To provide a method of manufacturing a bent member which is hard to generate wrinkles and projecting and recessing parts although performing complicated working control. SOLUTION: In the method of manufacturing the bent member having a bent part by restraining both ends of a hollow shape material K respectively with rotary receiving bases 1, 1 which are supported rotatably and imparting pressurizing force to the hollow shape material K in such a state, the hollow shape material K is restrained by the rotary receiving bases 1, 1 in such a manner that the minimum separated distance e between the inside edge Ka of the hollow shape material K and the center line P of rotation of the rotary receiving base 1 satisfies the following expression and the pressurizing force in a direction along a plane taking the center line P of rotation as the normal line is imparted to the hollow shape material K while keeping the separated distance L of the center lines P, P of rotation of the rotary receiving bases 1, 1 constant. äS-(1+a)×L/2+h×θ}/tanθ<e≤äS-(1-a/5)×L/2}/tanθ[where, S is a reference length (=r×θ+(L/2-rsinθ)/cosθ); r is the bend radius (mm); 2θis a bend center angle (rad); h is the girder height (mm) of the hollow shape material; and a is the tensile breaking strain of a material which comprises the hollow shape material]. COPYRIGHT: (C)2011,JPO&INPIT |
