Patent ID: 8833127
Filing Date: 2014-09-16
Classification: B21C,B21D,Y10T

Abstract:
1. A method of manufacturing a hollow member having a hollow metal body which has a closed transverse cross-sectional shape and which is constituted by a single piece in a lengthwise direction, and characterized in that the hollow metal body has at least a first region and a second region in the lengthwise direction, and in that the transverse cross-sectional shape of the hollow metal body in the first region is different from the transverse cross-sectional shape of the hollow metal body in the second region, the method comprising: supporting a hollow metal material being worked having a closed transverse cross-sectional shape at a first position while feeding it in its lengthwise direction, heating the material being worked at a second position downstream of the first position in the feed direction of the material being worked, carrying out working of the heated material in the feed direction of the material, at a third position downstream of the second position, the working modifying the transverse cross sectional shape of the material along a length of the material being worked to produce the hollow member after completion of working that has a transverse cross-sectional shape that changes along a length of the hollow member, cooling the worked material at a fourth position downstream of the third position in the feed direction of the material being worked, and carrying out bending of the material being worked by moving a mechanism that grips the material being worked downstream of the fourth position in the feed direction of the material being worked two dimensionally or three dimensionally.