Time-varying mesh stiffness is considered the primary excitation in gear vibrations. An accurate evaluation of mesh stiffness is of great importance when studying gear vibrations. Based on contact mechanics and gear engagement principle, we propose an improved analytical model to determine gear mesh stiffness. Gears with addendum modification and varying-load conditions are considered in the presented model. It is shown that the gear mesh stiffness is load-dependent, and the contribution of each component to the gear mesh stiffness is discussed. Experimental investigations based on strain gauges are presented to measure the mesh stiffness of an internal spur gear under different loading torques. In addition, existing methods are compared and discussed with the presented model. The results indicate that the proposed model can calculate time-varying mesh stiffness accurately under non-stationary conditions.

时变啮合刚度被认为是齿轮振动的主要激励因素。在研究齿轮振动时，准确评估啮合刚度非常重要。基于接触力学和齿轮啮合原理，我们提出了一种改进的分析模型来确定齿轮啮合刚度。在提出的模型中考虑了具有齿顶修改和负载条件变化的齿轮。结果表明，齿轮啮合刚度与载荷有关，讨论了每个部件对齿轮啮合刚度的贡献。提出了基于应变仪的实验研究，以测量不同负载扭矩下内部正齿轮的啮合刚度。另外，将现有方法与提出的模型进行比较和讨论。