Patent ID: 7565274

Claim:
A bending life predicting method of predicting a bending life span of each wire of a plurality of wires induced by vibration, at least two points of each of the plurality of wires being constrained, the method comprising the steps of: a pre-storing step of pre-storing each predicting function representing relationships among atmosphere temperatures, stresses and bending life spans for the plurality of wires; a setting step of setting the plurality of wires, the atmosphere temperatures, pre-vibration shapes of the plurality of wires, and constraint conditions of the plurality of wires; a finite element model forming step of forming finite element models of the plurality of wires by using a finite element method; a vibration analyzing step of calculating natural frequencies for the pre-vibration shapes and calculating stresses in individual finite elements of the finite element models which correspond to the natural frequencies, respectively; a maximum stress retrieving step of retrieving a maximum stress from the stresses calculated in the vibration analyzing step, for each of the plurality of wires; a predicting function readout step of reading predicting functions corresponding to the atmosphere temperatures set in the setting step, respectively; a bending life predicting step of acquiring a bending life span corresponding to the maximum stress of each of the plurality of wires while referring to the predicting functions read out in the predicting function readout step, and obtaining a shortest bending life span from the bending life spans; and an output step of outputting the shortest bending life span obtained in the bending life predicting step.