Modification Design And Experiment Of Gears For A Certain Transmission

Transmission is one of the most significant part of automotive transmission system in a car,which is used to change the torque,speed and the direction output from the engine to the driving wheels.Its performance does have direct influence on the entire performance of the car.As the most extensive form for the mechanical transmission system,the gear also plays a very important role.The bearing capacity of the gear determines the performance of the transmission to a large extent.Therefore,it is necessary for us to improve the bearing capacity of the gearbox to improve the performance of transmission.Lots of research shows that the modification is an effective way to solve the problem of bearing capacity of the gear.With the development of automobile industry,there arise higher requirements for cars.A company wants to increase the transmission torque rating to 150 N-m.Under this premise,this paper carries on the bearing capacity of the gear through the finite element analysis method,to determine whether it can satisfy the new requirements.What’s more,concrete modification measure is put forward due to that with the purpose of providing some theoretical basis for modification design of gearbox gear,which can make contribution to the improvement of carrying capacity of gearbox gear.Firstly,based on the meshing theory of gears,the tooth profile of involute helical gears is deduced and the transition curve is validated by Mathcad.Then,I use Pro/E to model the involute gears parametrically to compare and analyze several modeling methods to find a better modeling method so that the obtained helical gear model can be truly parameterized and you can generate a new model through any reasonable input.Next I use Pro/E to complete the gear assembly.Secondly,put the established gear assembly into ANSYS Workbench for finite element analysis.Carry out the ultimate load analysis of the gears under the original maximum input torque to verify the validity of the finite element analysis by comparing with the theoretical calculation.And then enforce the new input torque to check out the solution analysis data to determine whether it can meet the new requirements.Next,try to propose suitable modification curve measures for the transmission gears through the analysis acquired from ANSYS Workbench based on the theory of the existing gear modification system and combining with the actual conditions.Then establish the parametric model of the modified gear pair in Pro/E and put into the ANSYS finite element software to acquire data of the load carrying capacity for gears under the new input torque to compare with previous data,to verify the effectiveness and rationality of the modification.Finally,go on the transmission gear fatigue test based on a light-vehicle transmission test bench,to verify the results of finite element analysis.