Method of bending a long length of a member and bending apparatus for use in such method

Abstract

The method of bending the long length of the member and a bending apparatus which are capable of restraining the occurrence of wrinkles in flanges of the long length of the member, preventing free end sides of the flanges from buckling, and setting and taking out the long length of the member easily in bending a long length of a member in the longitudinal direction, which is approximately L-shaped or U-shaped in cross section and has a platelike bottom portion and flanges installed in a standing manner at the end of the platelike bottom portion, it is to provide. By using an inner forming assembly forming an inner bent shape of the long length of the member, an outer forming assembly having a forming pad being capable of projecting and retracting so as to form an outer bent shape of the long length of the member and die plate being rotatable following the forming pad and a sidewall provided in the longitudinal direction of the outer forming assembly, and by pressing the long length of the member in the outer forming assembly with the inner forming assembly and by doing the ironing of the flanges with the sidewall and the inner forming assembly, the occurrence of wrinkles in flanges is restrained, and free end sides of the flanges is prevented from buckling by extending gradually a bending fulcrum through a retraction of the forming pad and rotations of the die plates. Further, by installing a moving mechanism to the sidewall, setting and taking out the long length of the member is facilitated.

What is claimed is:  
     
         1 . A method of bending a long length of a member, wherein, in a long length of a member having a platelike bottom portion ( 1 ) and flanges ( 2 ) installed in a standing manner at the end of the platelike bottom portion ( 1 ), free end sides of the flanges ( 2 ) shrink and platelike bottom portion ( 1 ) sides of the flanges ( 2 ) expand, characterized in that, in bending the long length of the member by using an inner forming assembly ( 20 ) forming an inner bent shape of the long length of the member and an outer forming assembly ( 6 ) forming an outer bent shape of the long length of the member and by pressing the platelike bottom portion ( 1 ) in said outer forming assembly ( 6 ) with said inner forming assembly ( 20 ), said flanges ( 2 ) are pressed from both sides thereof between a sidewall ( 8 ) of said outer forming assembly ( 6 ) and said inner forming assembly ( 20 ), respectively, and bending is carried out while doing the ironing of said flanges ( 2 ) with said sidewall ( 8 ) and said inner forming assembly ( 20 ).  
     
     
         2 . A bending apparatus for a long length of a member for carrying out the bending in which, in a long length of a member having a platelike bottom portion ( 1 ) and flanges ( 2 ) installed in a standing manner at the end of the platelike bottom portion ( 1 ), free end sides of the flanges ( 2 ) shrink and platelike bottom portion ( 1 ) sides of the flanges ( 2 ) expand, including an inner forming assembly ( 20 ) forming an inner bent shape of the long length of the member and an outer forming assembly ( 6 ) forming an outer bent shape of the long length of the member, bending the long length of the member by pressing the platelike bottom portion ( 1 ) in said outer forming assembly ( 6 ) with said inner forming assembly ( 20 ), characterized in that said flanges ( 2 ) are pressed from both sides thereof between a sidewall ( 8 ) provided in said outer forming assembly ( 6 ) and said inner forming assembly ( 20 ), respectively, and the bending is carried out so as to do the ironing of said flanges ( 2 ) with said sidewall ( 8 ) and said inner forming assembly ( 20 ).  
     
     
         3 . The bending apparatus for a long length of a member as set forth in  claim 2 , the bending apparatus having a forming pad ( 9 ) ad die plates ( 10 ) in the longitudinal direction in such a way that said outer forming assembly ( 6 ) forms an outer bent shape of the long length of the member, characterized in that said forming pad  9  is installed so as to be capable of projecting and retracting by being applied with a force toward the direction of said inner forming assembly ( 20 ) by a means ( 16 ) of applying a force and the sides of said forming pad ( 9 ) of said die plates ( 10 ) are installed rotatably following a projection/retraction of said forming pad ( 9 ).  
     
     
         4 . The bending apparatus for a long length of a member as set forth in either  claim 2  or  claim 3 , characterized in that the bending apparatus have a moving mechanism for moving said sidewalls ( 8 ) away from said flanges ( 2 ).