Aiming at the structural feature of drive gears of diesel and taking crankshaft helical gears as the research object

the gear longitudinal contact stress distribution and influence of structural parameters are analyzed and calculation by using three dimensional contact finite element analysis method.The results agreed well with that of the conventional theory method

the reasonability and credibility of the results by finite element method is verified.This study shows that non-uniform contact stress distribution is caused by the longitudinal clearance inequality of the gear pair resulted by big axial bending deformation.Contact stress distribution is improved greatly by utilizing the helix angle modification method.It can provide support for gear design.