FEA-based Structure Optimization for the Drive End Housing of an Automotive Starter

Drive end housing fracture is the most frequent and severe failure mode of an automotive starter in service. In order to get a sufficient knowledge about nature of this failure and make optimization, the drive end housing of QDJ273A reduction type starter was set as an example to investigate. FEA results show that the round corner radius r has a great influence on stress and strain level, e.g. the maximum stress near the round corner decreases 51% while r increases from 2 mm to 12 mm, the maximum strain also decreases considerably. Anti-fracture structure optimization which mainly includes improving the round corner radius r as large as possible within confines was conducted. Industry practices show that a great progress has been made, pertinent product sales return ratio due to drive end housing fracture has descended from 23.3% to not exceeding 2%.