On gear tooth stiffness evaluation

• Stiffness estimation of gear teeth as a function of the contact point position.
• Consistent stiffness evaluation using the elastic energy and the applied load.
• Two factors have a major influence on the stiffness; rim thickness and load.
• FEA shows that a model including the gear rim and a single tooth is sufficient.
• Tooth stiffness is linear leading to simple evaluation of meshing stiffness.

The estimation of gear stiffness is important for determining the load distribution between the gear teeth when two sets of teeth are in contact. Two factors have a major influence on the stiffness; firstly the boundary condition through the gear rim size included in the stiffness calculation and secondly the size of the contact. In the FE calculation the true gear tooth root profile is applied. The meshing stiffnesses of gears are highly non-linear, it is however found that the stiffness of an individual tooth can be expressed in a linear form assuming that the contact width is constant.