BENDING METHOD, AND BENDING MACHINE

摘要

PROBLEM TO BE SOLVED: To improve the passing-bending accuracy by suppressing dispersion of the bending angle in the longitudinal bending direction of a work. SOLUTION: Maximum difference between blades in a range corresponding to the bending length of the work W is operated based on a formula of deflection of one table 9 and a formula of deflection of the other table 11 while changing the crowning pressure ratio, the crowning pressure ratio for minimizing the maximum difference between the blades is selected as the optimum crowning pressure ratio, and the work W is bent in cooperation with a punch 13 and a die 15 while operating actuators 19L and 19R for crowning so as to the optimum crowning pressure ratio can be obtained.