BENDING DEVICE

PROBLEM TO BE SOLVED: To easily perform a work of correcting a bending load so as to obtain a target bending angle.SOLUTION: A function expression that expresses relative displacement between a bending load to be applied on a work W and the bending angle of the work W is calculated based on bending conditions such as the material of the work W and on a target bending angle . A target bending load BF for making the bending angle of the work W a target bending angle is calculated based on the calculated function expression. When the bending angle formed by bending work performed with the calculated target bending load BF is deviated from the target bending angle , a correction function expression is calculated by correcting the function expression so that the load corresponding to a bending angle 1, which is the angle deviated from the target bending angle of the calculated function expression, becomes the target bending load BF. Based on the correction function expression, the bending load corresponding to the target bending angle is calculated as a target bending load BF2 after correction, and bending is carried out with the calculated target bending load BF2.