Study Of Time Varying Mesh Stiffness And Dynamic Performance Of Face-gear Pair

Dynamic performance of gear transmission system has a vital influence on the performance of machine. Inversely, the mesh stiffness of gear pair, as a foundation of gear dynamics analysis, is closely relative to its dynamic performance. Hence the main motivation of the present works is to propose a new numerical calculation method for time varying mesh stiffness of face gear pair by using Finite element method.The main contents of the present works are listed as following:1.Based on the meshing theory of face gear pair, the tooth surface equation is deduced, which is solved with a numerical method by MATLAB. Geometric modeling software of face gear pair is developed with the secondary development of CATIA based on the geometric theory of the NURBS surface.2.A method for calculating the mesh stiffness of face gear transmission system based on Finite element method is proposed. To validate the calculation method, a spur gear pair is adopted to calculate the mesh stiffness and loaded static transmission error. The results show that the mesh stiffness is identical with it from ISO6336method.3.The load transmission error, load distribution and mesh stiffness of face gear drive system are obtained. The minimum of mesh stiffness occurs when one tooth enters into engagement and another one disengages from the engaging state and the load concentrates on the third tooth.4.The mean value of the mesh stiffness increases while variation of amplitude reduces with the increase of the load. However, the thickness of hub has a significant influence on the transmission performance of the face gear drive system. When the thickness of hub decreases, the mesh stiffness curve varies obviously due to the changing of the contact pattern and contact path. The effect of hub thickness on mesh stiffness is enlarged with the increase of the load.5. Based on the theory of nonlinear dynamics and finite element explicit algorithm, the dynamic meshing force of the face-gear is studied based on ABAQUS. The laws of the contact force and the tooth root bending stress in dynamic meshing of face-gear are obtained.The association relations between the two typical working factors, rotation speed and load, with dynamic mesh force are indicated. The work of the present paper is valuable for analyzing the dynamic performance of high-performance face-gear driver.6. The theoretical results are validated with a simple rolling check test experimentally. The contact areas of the face gear pair are checked out, whose results agree with the contact areas of LTCA.