Patent ID: 7770426
Filing Date: 2010-08-10
Classification: B21D

Abstract:
1. A method of bending a blade member in which a strip-like blade member having an blade edge in one end edge in a width direction is intermittently fed to a working die portion, and a bending process is performed by the working die portion during stoppage of the feeding process, wherein: said bending process by said working die portion includes: a width-direction bending step of bending said blade member in the width direction; and a thickness-direction bending step of, after said bending process, bending said blade member in a thickness direction; in the width-direction bending step for said blade member, said blade member is clamped by a pair of rotary press claws disposed in said working die portion, from both sides in the thickness direction to be compressed in the thickness direction, whereby the compressed portion is extended in a longitudinal direction of said blade member and said blade member is bent in the width direction; in said thickness-direction bending step for said blade member, said working die portion comprises: a thickness-direction bending shaft; and a thickness-direction bending cylinder which is fitted in a turning paired state onto said thickness-direction bending shaft, a blade member passing hole which allows said blade member to pass therethrough is penetratingly formed in said thickness-direction bending shaft in a direction perpendicular to an axis of said thickness-direction bending shaft, first and second openings which are opposed respectively to outlet and inlet opening ends of said blade member passing hole are formed in said thickness-direction bending cylinder, and said blade member which is passed from said blade member passing hole to said first opening via said second opening is bent in the thickness direction by relatively rotating said thickness-direction bending shaft and said thickness-direction bending cylinder; wherein said width-direction bending process is performed by a configuration where said pair of rotary press claws are attached to a pair of rotary press driving shaft and rotary press driven shaft which are opposed in a vertical posture to each other on both sides across said blade member, in a manner that said rotary press claws are rotatable in mutually opposite directions, so that tip end edges of said claws are projected to outsides of said shafts, respectively, and said pair of rotary press driving shaft and rotary press driven shaft are relatively rotated to cause said rotary press claws to approach each other; wherein said thickness-direction bending process is performed by a configuration where said thickness-direction bending shaft is formed into a cylindrical shape and fixed, said pair of rotary press driving shaft and rotary press driven shaft are housed in said thickness-direction bending shaft, a rotary press cylinder having blade member passing holes is inserted in a manner that said blade member passing holes communicate with said blade member passing hole of said thickness-direction bending shaft, and said thickness-direction bending cylinder which is fitted in a turning paired state onto said thickness-direction bending shaft is rotated; and wherein said thickness-direction bending process is performed with tilting said thickness-direction bending shaft and said thickness-direction bending cylinder with respect to said blade member so as to coincide with a curvature of said blade member which has been bent in the width direction.