Design Of Tooth Shape Surface And Analysis Of Bearing Characteristics Of Face Gear Transmission

Face gear drive is a new type of gear drive mode.When bevel gear and cylindrical gear mesh and the axes of the two wheel are vertical,it is called face gear drive.Namely face gear drive is a special bevel gear transmission.Compared with bevel gear,face gear transmission has attracted more and more attention in the aviation industry because of its advantages,such as large coincidence degree,compact structure,low motion noise and large transmission ratio.Because of its good function of ’split of torque-sink of torque’,it also shows a broad application prospect in helicopter power transmission system.The main research contents and achievements of this paper are as follows:(1)In order to improve the meshing and load-bearing contact characteristics of face gear pair,the tooth surface of face gear pair is actively modified.Active modification of gear is a method that can directly pre control the meshing performance of gear.The geometric performance of opposite gear pair can be pre controlled by active modification,so as to pre control the load-bearing contact characteristics of gear surface.It shows that there is an inevitable relationship between the micro modification parameters of active modification and the load-bearing contact characteristics of face gear pair.In order to further research the influence of micro modification parameters on the bearing contact characteristics of face gear,Firstly,the finite element assembly model of active modification of face gear pair is established;Secondly,the load-bearing contact characteristics of face gear pairs with different modification parameters are obtained by finite element simulation;Finally,through the influence of different modification parameters on the bearing characteristics of face gear pair,the optimal value range of micro parameters of active modification is determined.So as to provide design basis for the processing and application of face gear.(2)The tooth surface of face gear is a complex spatial special-shaped curved surface,which makes it difficult to manufacture and high processing cost.In order to process face gear simply and efficiently,according to the tooth profile characteristics of traditional face gear,the hypothesis that the tooth surface of face gear can be composed of a series of straight line families is put forward.The existence of tooth surface straight line families is verified by establishing spatial straight line equations on its tooth surface;The mathematical model of developable ruled surface gear is established based on involute,and its tooth surface is modified;The deviation between the linear tooth profile and the theoretical tooth profile of face gear is analyzed,and the influence of transmission ratio on it is discussed.The results show that the deviation between the two is small when the transmission ratio is large,and the straight tooth profile can be used instead of theoretical tooth profile.(3)The meshing characteristics of developable ruled surface gear are evaluated by tooth surface contact analysis;In order to illustrate the feasibility of the developable ruled surface replacing the theoretical tooth surface,the load-bearing contact analysis is carried out,and the load-bearing characteristics are compared with the theoretical surface gear pair and the active modified surface gear pair.The results show that the load-bearing capacity of the developable ruled surface is equivalent to that of the theoretical tooth surface.