Study of a method to predict the bending life of wiring harness

摘要

We propose a new method to predict the bending life of wiring harness(W/H) for automobile using FEM analysis. The bending life is defined as the number of bending cycles until a wire breakage. The bending life of polyvinyl chloride(PVC) insulated W/H is shorter under low temperature conditions than at normal temperatures. In low temperature, cracking begins on the insulation surface of W/H and culminates in wire breakage upon reaching to the conductor. S-N curve, where S is the amount of change in strain on the insulation surface and N is bending life, was obtained by bending test using a simple wire. By FEM calculation of the bending strain of W/H, bending life of W/H can estimate using this S-N curve.