The tooth surface analysis of a standard helical gear pair before modification under load conditions is shown in the figure. At the end of the calculation cycle, the contact stress value on the tooth surface is 115.6 MPa, the shear stress value is 81.301 MPa, and the maximum equivalent stress is 245.07 MPa.
During the meshing cycle of a helical gear, the distribution range of the entire maximum equivalent stress nephogram on the tooth surface indicates that the contact imprint of an unmodified helical gear pair is a straight line that obliquely distributes the entire tooth surface, with the stress value distributed over the entire tooth surface, and there is tooth tip contact and edge contact.